| Título | Revista | Autores | Año | Línea de Investigación | DOI | Enlace | Páginas | Volumen | ISSN | Index | Acceso | Idioma | Abstract |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| La articulación regional de la movilización ambiental en Chile: el caso de la Asociación Regional Ambiental de O’Higgins (ARAO) | EURE | Martínez, F.; Maillet, A. | 2025 | Gobernanza e Interfaz Ciencia y Política | 10.7764/EURE.51.152.04 | https://www.eure.cl/index.php/eure/article/view/EURE.51.152.04 | 1-26 | Vol: 51.0 Issue: 152.0 | Thomson Reuters ISI (SSCI) | ||||
| Distributed parameter identification for the Navier–Stokes equations for obstacle detection | Inverse Problems | Aguayo, J.; Bertoglio, C.; Osses, A. | 2024 | Ciudades Resilientes | 10.1088/1361-6420/ad1133 | https://iopscience.iop.org/article/10.1088/1361-6420/ad1133 | art015012 | Vol: 40.0 Issue: 1.0 | 02665611 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | We present a parameter identification problem for a scalar permeability field and the maximum velocity in an inflow, following a reference profile. We utilize a modified version of the Navier–Stokes equations, incorporating a permeability term described by the Brinkman’s Law into the momentum equation. This modification takes into account the presence of obstacles on some parts of the boundary. For the outflow, we implement a directional do-nothing condition as a means of stabilizing the backflow. This work extends our previous research published in (Aguayo et al 2021 Inverse Problems 37 025010), where we considered a similar inverse problem for a linear Oseen model with do-nothing boundary conditions on the outlet and numerical simulations in 2D. Here we consider the more realistic case of Navier–Stokes equations with a backflow correction on the outflow and 3D simulations of the identification of a more realistic tricuspid cardiac valve. From a reference velocity that could have some noise or be obtained in low resolution, we define a suitable quadratic cost functional with some regularization terms. Existence of minimizers and first and second order optimality conditions are derived through the differentiability of the solutions of the Navier–Stokes equations with respect to the permeability and maximum velocity in the inflow. Finally, we present some synthetic numerical test based of recovering a 2D and 3D shape of a cardiac valve from total and local velocity measurements, inspired from 2D and 3D MRI. © 2024 Institute of Physics Publishing. All rights reserved. |
| PatagoniaMet: A multi-source hydrometeorological dataset for Western Patagonia | Scientific Data | Aguayo, R.; León-Muñoz, J.; Aguayo, M.; Baez-Villanueva, O.; Zambrano-Bigiarini, M.; Fernández, A.; Jacques-Coper, M. | 2024 | Agua y Extremos; Zonas Costeras | 10.1038/s41597-023-02828-2 | https://doi.org/10.1038/s41597-023-02828-2 | art6 | Vol: 11 Issue: 1 | 20524463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Western Patagonia (40–56°S) is a clear example of how the systematic lack of publicly available data and poor quality control protocols have hindered further hydrometeorological studies. To address these limitations, we present PatagoniaMet (PMET), a compilation of ground-based hydrometeorological data (PMET-obs; 1950–2020), and a daily gridded product of precipitation and temperature (PMET-sim; 1980–2020). PMET-obs was developed considering a 4-step quality control process applied to 523 hydrometeorological time series obtained from eight institutions in Chile and Argentina. Following current guidelines for hydrological datasets, several climatic and geographic attributes were derived for each catchment. PMET-sim was developed using statistical bias correction procedures, spatial regression models and hydrological methods, and was compared against other bias-corrected alternatives using hydrological modelling. PMET-sim was able to achieve Kling-Gupta efficiencies greater than 0.7 in 72% of the catchments, while other alternatives exceeded this threshold in only 50% of the catchments. PatagoniaMet represents an important milestone in the availability of hydro-meteorological data that will facilitate new studies in one of the largest freshwater ecosystems in the world. © 2024, The Author(s). |
| Public Perception of Drought and Extreme Rainfall Impacts in a Changing Climate: Aconcagua Valley and Chañaral, Chile | Sustainability (Switzerland) | Aldunce, P.; Haverbeck, F.; Sapiains, R.; Quilaqueo, A.; Castro, C. | 2024 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.3390/su16187916 | https://doi.org/10.3390/su16187916 | art7916 | Vol: 16.0 Issue: 18.0 | 20711050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Droughts and extreme rainfall events are two of the hazards that affect many people in the world and are frequent and complex hazards, the rate of occurrence and magnitude of which are expected to increase in a changing climate. In this context, understanding how different actors perceive changes in climate, drought, and extreme rainfall events and their impacts is relevant in contributing to successfully implementing adaptation strategies to reduce their impacts. This research seeks to explore the main changes the climate has undergone and the impacts of drought and precipitation events, as perceived at local levels by different stakeholders. A multi-method approach was applied, including qualitative methods such as observation, 51 semi-structured interviews, and document reviews in Chañaral and the Aconcagua Valley, Chile. This research shows what the perceived changes in climate are and that drought and extreme rainfall events have affected the well-being of the local people by severely impacting the economy, the environment, social interactions, quality of life, and human health. Additionally, the perception of climate change and its impacts vary depending on the type of hazard and the social, geographical, and environmental contexts in which communities live. This study is useful as it has generated knowledge relevant to inform policy decisions, practice, and theory. © 2024 by the authors. |
| HESS Opinions: The unsustainable use of groundwater conceals a "Day Zero" | Hydrology and Earth System Sciences | Alvarez-Garreton, C.; Boisier, J.; Garreaud, R.; González, J.; Rondanelli, R.; Gayó, E.; Zambrano-Bigiarini, M. | 2024 | Agua y Extremos; Ciudades Resilientes; Zonas Costeras | 10.5194/hess-28-1605-2024 | https://doi.org/10.5194/hess-28-1605-2024 | 1605-1616 | Vol: 28.0 Issue: 7.0 | 10275606 | Thomson Reuters ISI (SCIE) | English | Water scarcity is a pressing global issue driven by increasing water demands and changing climate conditions. Based on novel estimates of water availability and water use in Chile, we examine the challenges and risks associated with groundwater (GW) withdrawals in the country's central-north region (27-35°ĝ€¯S), where extreme water stress conditions prevail. As total water use within a basin approaches the renewable freshwater resources, the dependence on GW reserves intensifies in unsustainable ways. This overuse has consequences that extend beyond mere resource depletion, manifesting into environmental degradation, societal conflict, and economic costs. We argue that the "Day Zero"scenario, often concealed by the uncertain attributes of GW resources, calls for a reconsideration of water allocation rules and a broader recognition of the long-term implications of unsustainable GW use. Our results offer insights for regions worldwide facing similar water scarcity challenges and emphasize the importance of proactive and sustainable water management strategies. © 2024 Camila Alvarez-Garreton et al. | |
| Acidithiobacillia class members originating at sites within the Pacific Ring of Fire and other tectonically active locations and description of the novel genus ‘Igneacidithiobacillus’ | Frontiers in Microbiology | Arisan, D.; Moya-Beltrán, A.; Rojas-Villalobos, C.; Issotta, F.; Castro, M.; Ulloa, R.; Chiacchiarini, P.; Díez, B.; Martín, A.; Ñancucheo, I.; Giaveno, A.; Johnson, D.; Quatrini, R. | 2024 | Zonas Costeras | 10.3389/fmicb.2024.1360268 | https://doi.org/10.3389/fmicb.2024.1360268 | art1360268 | Vol: 15.0 | 1664302X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Recent studies have expanded the genomic contours of the Acidithiobacillia, highlighting important lacunae in our comprehension of the phylogenetic space occupied by certain lineages of the class. One such lineage is ‘Igneacidithiobacillus’, a novel genus-level taxon, represented by ‘Igneacidithiobacillus copahuensis’ VAN18-1T as its type species, along with two other uncultivated metagenome-assembled genomes (MAGs) originating from geothermally active sites across the Pacific Ring of Fire. In this study, we investigate the genetic and genomic diversity, and the distribution patterns of several uncharacterized Acidithiobacillia class strains and sequence clones, which are ascribed to the same 16S rRNA gene sequence clade. By digging deeper into this data and contributing to novel MAGs emerging from environmental studies in tectonically active locations, the description of this novel genus has been consolidated. Using state-of-the-art genomic taxonomy methods, we added to already recognized taxa, an additional four novel Candidate (Ca.) species, including ‘Ca. Igneacidithiobacillus chanchocoensis’ (mCHCt20-1TS), ‘Igneacidithiobacillus siniensis’ (S30A2T), ‘Ca. Igneacidithiobacillus taupoensis’ (TVZ-G3 TS), and ‘Ca. Igneacidithiobacillus waiarikiensis’ (TVZ-G4 TS). Analysis of published data on the isolation, enrichment, cultivation, and preliminary microbiological characterization of several of these unassigned or misassigned strains, along with the type species of the genus, plus the recoverable environmental data from metagenomic studies, allowed us to identify habitat preferences of these taxa. Commonalities and lineage-specific adaptations of the seven species of the genus were derived from pangenome analysis and comparative genomic metabolic reconstruction. The findings emerging from this study lay the groundwork for further research on the ecology, evolution, and biotechnological potential of the novel genus ‘Igneacidithiobacillus’. Copyright © 2024 Arisan, Moya-Beltrán, Rojas-Villalobos, Issotta, Castro, Ulloa, Chiaccharini, Díez, Martín, Ñancucheo, Giaveno, Johnson and Quatrini. |
| Impacts of a short-interval severe fire on forest structure and regeneration in a temperate Andean Araucaria-Nothofagus forest | Fire Ecology | Arroyo-Vargas, P.; Busby, S.; Veblen, T.; González, M.; Holz, A. | 2024 | Cambio de Uso de Suelo | 10.1186/s42408-024-00327-2 | https://doi.org/10.1186/s42408-024-00327-2 | a93 | Vol: 20.0 Issue: 1.0 | 1933-9747 | Thomson Reuters ISI (SCIE) | Gold Open Access | en | Warmer climate conditions are altering fire regimes globally, eroding the capacity of forest ecosystems to resist and recover from natural disturbances like wildfire. Severe and rapidly repeated wildfires are promoting tree regeneration failure of obligate-seeders and/or fire-sensitive species in temperate forests of the Southern Hemisphere. We collected post-fire field data to evaluate whether forest structure and tree regeneration responses varied between two Andean forest study areas dominated by the threatened Gondwanan conifer Araucaria araucana and Nothofagus species (southern beeches) — one area burned once, the other reburned after 13 years. Tree mortality was high across species after a single high severity and/or repeated wildfire, although some A. araucana trees were able to survive both events. Post-fire seedling regeneration of A. araucana and Nothofagus spp. was poor in areas affected by severe wildfires, and the latter was absent from reburned plots. A key driver of this regeneration failure was increasing distance to live seed source trees, which was negatively correlated with these species’ post-fre seedling abundances. In contrast, species with the capacity to regenerate via resprouting (A. araucana, N. alpina, N. obliqua) did so after a single high severity fire; however, only a single Nothofagus species (N. alpina) resprouted abundantly after a reburn. Our fundings suggest that high severity and short-interval fires can drastically change the structure of and limit post-fre tree regeneration in Araucaria-Nothofagus forests, promoting alternative post-fire forest ecosystem trajectories. Resprouting species of the Nothofagus genus, especially N. alpina, exhibit the greatest resilience to these emerging fire patterns. These forests are currently facing an unprecedented climatic shift toward greater fire activity, where resprouting is the favored regeneration strategy. If the occurrence of severe and short-interval fires increases in the coming decades, as predicted, we expect Araucaria-Nothofagus forests to shift toward a drier, more flammable shrubland ecosystem state. |
| On the timescale of drought indices for monitoring streamflow drought considering catchment hydrological regimes | Hydrology and Earth System Sciences | Baez-Villanueva, O.; Zambrano-Bigiarini, M.; Miralles, D.; Beck, H.; Siegmund, J.; Alvarez-Garreton, C.; Verbist, K.; Garreaud, R.; Boisier, J.; Galleguillos, M. | 2024 | Agua y Extremos; Cambio de Uso de Suelo | 10.5194/hess-28-1415-2024 | https://doi.org/10.5194/hess-28-1415-2024 | 1415-1439 | Vol: 28.0 Issue: 6.0 | 10275606 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | There is a wide variety of drought indices, yet a consensus on suitable indices and temporal scales for monitoring streamflow drought remains elusive across diverse hydrological settings. Considering the growing interest in spatially distributed indices for ungauged areas, this study addresses the following questions: (i) What temporal scales of precipitation-based indices are most suitable to assess streamflow drought in catchments with different hydrological regimes? (ii) Do soil moisture indices outperform meteorological indices as proxies for streamflow drought? (iii) Are snow indices more effective than meteorological indices for assessing streamflow drought in snow-influenced catchments? To answer these questions, we examined 100 near-natural catchments in Chile with four hydrological regimes, using the standardised precipitation index (SPI), standardised precipitation evapotranspiration index (SPEI), empirical standardised soil moisture index (ESSMI), and standardised snow water equivalent index (SWEI), aggregated across various temporal scales. Cross-correlation and event coincidence analysis were applied between these indices and the standardised streamflow index at a temporal scale of 1 month (SSI-1), as representative of streamflow drought events. Our results underscore that there is not a single drought index and temporal scale best suited to characterise all streamflow droughts in Chile, and their suitability largely depends on catchment memory. Specifically, in snowmelt-driven catchments characterised by a slow streamflow response to precipitation, the SPI at accumulation periods of 12-24 months serves as the best proxy for characterising streamflow droughts, with median correlation and coincidence rates of approximately 0.70-0.75 and 0.58-0.75, respectively. In contrast, the SPI at a 3-month accumulation period is the best proxy over faster-response rainfall-driven catchments, with median coincidence rates of around 0.55. Despite soil moisture and snowpack being key variables that modulate the propagation of meteorological deficits into hydrological ones, meteorological indices are better proxies for streamflow drought. Finally, to exclude the influence of non-drought periods, we recommend using the event coincidence analysis, a method that helps assessing the suitability of meteorological, soil moisture, and/or snow drought indices as proxies for streamflow drought events. © 2024 The Author(s). |
| Assessing the incorporation of latent variables in the estimation of the value of a statistical life | Risk Analysis | Barrientos, M.; Vásquez Lavín, F.; Ponce Oliva, R. | 2024 | Cambio de Uso de Suelo | 10.1111/risa.14286 | https://doi.org/10.1111/risa.14286 | 02724332 | Thomson Reuters ISI (SCIE; SSCI) | English | For many years, the economic literature has recognized the role of attitudes, beliefs, and perceptions in estimating the value of a statistical life (VSL). However, few applications have attempted to include them. This article incorporates the perceived controllability and concern about traffic and cardiorespiratory risks to estimate VSL using a hybrid choice model (HCM). The HCM allows us to include unobserved heterogeneity and improve behavioral realism explicitly. Using data from a choice experiment conducted in Santiago, Chile, we estimate a VSL of US$3.78 million for traffic risks and US$2.06 million for cardiorespiratory risks. We found that higher controllability decreases the likelihood that the respondents would be willing to pay for risk reductions in both risks. On the other hand, concern about these risks decreases the willingness to pay for traffic risk reductions but increases it for cardiorespiratory risk reductions. © 2024 Society for Risk Analysis. | |||
| Tornadoes and Waterspouts in Chile [Tornados y Trombas en Chile] | Bastías-Curivil, C.; Rondanelli, R.; Vicencio, J.; Matus, F.; Caballero, V.; Munoz, F.; Barraza, J.; Campos, D.; Valenzuela, R.; de la Maza, A. | 2024 | Agua y Extremos; Zonas Costeras | 10.6084/M9.FIGSHARE.25119566.V3 | https://figshare.com/articles/dataset/Tornadoes_and_Waterspouts_in_Chile_Tornados_y_Trombas_en_Chile/25119566/3 | Figshare | Creative Commons Attribution 4.0 International | English | We provide a dataset of tornadoes and waterspouts in Chile from 1554 to present based in chronicles, newspaper articles, social media, scientific literature and books. The database includes only those events that have been qualified as more than likely a tornado or waterspout based on a subjective qualification by the researchers. For each tornado we provide at least one geographical location point, the local and UTC hour (if known) and for most cases an estimation of the intensity based on the Enhanced Fujita damage scale.The following are the parameters contained in the database: N°: This is the entry number or identifier for each record in the file.Location: The name of the place where the weather event occurred.Latitude: The geographical latitude coordinate of the event's location.Longitude: The geographical longitude coordinate of the event's location.Date (Gregorian Calendar): The date when the event occurred, according to the Gregorian calendar.Hour (local): The local time when the event occurred.Hour (UTC): The time of the event in Coordinated Universal Time (UTC).Sound: A binary indicator (usually 1 for 'Yes' and 0 for 'No') showing whether there was a notable sound associated with the event.Hail: A binary indicator showing whether hail was a feature of the weather event.Electric Storm: A binary indicator showing whether the event involved an electric storm.Damage: A binary indicator showing whether there was any damage resulting from the event.Tornado: A binary indicator showing whether a tornado was a part of the event.Waterspout: A binary indicator showing whether a waterspout was observed during the event.Register: This column refers to the existence of some witness account or visual material of a rotating column.Max. EF Rating: The maximum Enhanced Fujita Scale rating assigned to the tornado, indicating its intensity.Analyst: The name or initials of the person who analyzed or reported the event.Fatalities: The number of fatalities (deaths) caused by the event.Injured: The number of injuries reported due to the event.Link to Documents: References or links to documents where the event is described or recorded.Sources: The sources or references from where the information about the event is derived.Comments: Additional remarks or notes about the event, providing context or extra details. |
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| Systemic modeling strategies in public policy: an appraisal from literature | Environmental Science & Policy | Billi, M.; Allendes, A.; Jiliberto, R.; Ramos-Jiliberto, R.; Salinas, B.; Urquiza, A. | 2024 | Ciudades Resilientes | 10.1016/j.envsci.2024.103668 | https://www.doi.org/10.1016/j.envsci.2024.103668 | 103668 | Vol: 153.0 | 14629011 | Thomson Reuters ISI (SCIE) | English | Contemporary society has grown increasingly dependent on the integration of knowledge for decision-making. In this context, systemic modeling is acknowledged as a straightforward tool for representing and analyzing complex problems. To address how systemic modeling is being conducted to guide and support public policy-making, this study offers a brief synthesis of the literature on systemic modeling oriented to help public policy decision-making. The results are compared to three principles for good systemic modeling to support public policy, established by the authors: the model must a) be readable and manageable —to a basic level— by non-experts, b) require as little quantitative data as possible, and c) not generate spurious or ambiguous readings of their content or their outputs. To identify modeling patterns the models were subjected to a content analysis under eleven different categories. To depict the possible co-occurrence of these analyzed categories in order to describe different types of modeling, a multiple correspondence analysis was performed. We found different modeling patterns with a marked trend to use system modeling as a performative device to let emerging cognitively a new entity, the structure of a complex problem. Regarding our proposal for modeling public policy problems, it can be said that the modeling strategies that fit better with the proposed principles are those that were identified as qualitative and oriented to public policy. © 2024 Elsevier Ltd | |
| A pioneering approach to measure increased resilience to face climate change: insights from the Race to Resilience campaign | Environmental Research Communications | Billi, M.; Bórquez, R.; Varela, J.; Aldunce, P.; Aspee, N.; Beauchamp, E.; Berríos, P.; Cuevas, M.; Loboguerrero, A.; Mason Bustos, F.; Patwardhan, A.; Rojas, M. | 2024 | Agua y Extremos; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1088/2515-7620/ad6d37 | https://doi.org/10.1088/2515-7620/ad6d37 | art095006 | Vol: 6.0 Issue: 9.0 | 25157620 | Thomson Reuters ISI (SCIE) | English | This paper illustrates a methodology to measure the impact of resilience-building actions on the increased resilience of people and natural systems to face climate change, developed and field-tested around the Race to Resilience Campaign. Despite increasing acknowledgment of the need for robust methodologies and indicators to monitor and evaluate efforts across adaptation planning and implementation, and provide credibility, accountability and transparency to such actions, there is still a lack of sufficiently standardized and agreed upon metrics able to capture the effect of resilience-building actions. The proposal illustrated in this manuscript offers a pioneering approach for high-level tracking, monitoring and evaluation of resilience-building efforts of non-state actors, based on two complementing sets of metrics: depth metrics measure the degree to which an action is generating a change to fundamental conditions which can demonstrably be related to increasing resilience; while magnitude metrics offer a quantification of the beneficiaries that are affected by these changes. Underlying both stand the Resilience Attributes: properties which can be soundly associated with triggering resilience across different systems, and which can then be used to assess increased resilience ‘by proxy’: that is, by seeing how an action sets forth changes in properties commonly associated with resilience. These Attributes were identified based on updated scientific literature and co-construction exercises with global experts. The integration of Depth and Magnitude indices, adjusted by a Confidence Index evaluating data reliability, allows to estimate the overall contribution of a set of actions on increasing resilience against climate challenges. Based on the above, a possible Monitoring & Evaluation cycle is proposed, and an illustration is offered on two case studies from the Race to Resilience campaign. Key strengths, lessons learned and insights are summarized to stimulate the global discussion, in the context of the Global Stocktake and Global Goal on Adaptation. © 2024 The Author(s). Published by IOP Publishing Ltd. | |
| Transition in action: toward a social theory of the governance of transitions | Frontiers in Sociology | Billi, M.; Zurbriggen, C.; Urquiza, A.; Allendes, A. | 2024 | Ciudades Resilientes | 10.3389/fsoc.2024.1206050 | https://doi.org/10.3389/fsoc.2024.1206050 | art1206050 | Vol: 9.0 | 22977775 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | This article explores how a re-interpretation of the socio-technical, socio-ecological and transition design approaches to transition from the point of view of Niklas Luhmann’s general systems theory of society. The need to understand and promote changes that include a technological and ecological dimension has led to different approaches, such as socio-technical or socio-environmental approaches, to incorporate links with society. While these approaches often include sociological insights, they rarely offer a general understanding of how these are embedded into society. We need a new environmental sociology that helps catalyze change processes with a collectively reorganized society, empowering more radically transformative actions to change the current structures and processes that have led us to where we are today. The article offers a cross-sectional look at the socio-ecological and socio-technical systems literature, specifically for what concerns their understanding of the ‘systems’ in transition and how they can be governed, and re-interpret it from the theoretical lens of the deep sociological knowledge, which refers to the profound understanding of social systems and their dynamics, embedded in Luhmann’s theory of social systems. From here, we suggest the second-order coupling for a sociologically grounded understanding of the interactions that comprise socio-ecological and socio-technical systems, heterogeneous and almost self-organizing assemblies of social, technical, and natural elements and processes. At the same time, third-order couplings are analyzed, focused on governance, relationships between operations, and structures mediated by a deliberate attempt to ensure coherence and coordination against the autonomy and heterogeneity of socio-techno-ecological systems. Therefore, this manuscript offers a deeper conceptual and methodological understanding of socio-techno-ecological couplings and systems in the context of sustainability transformation and gives insights into its governance. Copyright © 2024 Billi, Zurbriggen, Urquiza and Allendes. |
| Territorial transitions in Latin America: a dialogue between social systems theory and socio-technical systems approaches | Cybernetics and Human Knowing | Billi, M.; Zurbriggen, C.; Urquiza, A.; Borquez, R.; Allendes, A. | 2024 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://chkjournal.com/node/485 | 153–174 | Vol: 31 Issue: 1-2 | 0907-0877 | Not indexed | English | |||
| CR2LUC: Historical (1950-2020) land use and land cover in continental Chile | Boisier, J.; Marinao, R. | 2024 | Agua y Extremos | 10.5281/ZENODO.13324250 | https://zenodo.org/doi/10.5281/zenodo.13324250 | Zenodo | Creative Commons Attribution 4.0 International | The CR2LUC product was created to track long-term land-use changes in Chile since 1950, using a method that combines historical data with satellite information. Unlike recent land use/cover estimates that rely heavily on satellite data, CR2LUC integrates various sources, including agricultural censuses and other national statistics. This reconstruction involves extensive data preprocessing, such as digitizing historical documents. Key data sources include Agricultural Censuses (1955, 1965, 1976, 1997, 2007), annual crop statistics (1997-2021), and cadastres for fruits, viticulture, and vegetation. This dataset has been developed within the framework of the Center for Climate and Resilience Research (CR2, ANID/FONDAP/1523A0002) and the research project ANID/FSEQ210001. |
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| CR2WU: Water use dataset for the period 1950-2020 in continental Chile. | Boisier, J.; Marinao, R.; Alvarez Garreton, C. | 2024 | Agua y Extremos | 10.5281/ZENODO.13324235 | https://zenodo.org/doi/10.5281/zenodo.13324235 | Zenodo | Creative Commons Attribution 4.0 International | The CR2WU dataset includes consumptive and non-consumptive water uses as volumetric fluxes from various sectors at the commune level (the smallest administrative unit in Chile), with annual resolution from 1950 to 2020. The computation involves two distinct methodologies: one for sectors encompassing land use, land-use change, and forestry (LULUCF) and another for other water-consuming sectors. This dataset been developed within the framework of the Center for Climate and Resilience Research (CR2, ANID/FONDAP/1523A0002) and the research project ANID/FSEQ210001. |
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| Infrastructure Conditions and Service Quality in Rural Drinking Water Systems: A Cluster Analysis of Community-Based Organizations in Chile | Journal of Water Resources Planning and Management | Bopp, C.; Nicolas-Artero, C.; Blanco, E.; Fuster, R. | 2024 | Agua y Extremos | 10.1061/JWRMD5.WRENG-6318 | https://doi.org/10.1061/JWRMD5.WRENG-6318 | art05024003 | Vol: 150.0 Issue: 6.0 | 07339496 | Thomson Reuters ISI (SCIE) | English | In many countries, the drinking water provision in rural areas is in the charge of the users themselves, who constitute rural water supply services (RWS) to operate and maintain the public infrastructure provided by the State. However, in practice, the condition of the components of the implied infrastructure managed by RWS varies considerably, which has important implications for delivering high-quality service. This case study explores the nexus among infrastructure conditions, performance outcomes, and organization characteristics using the case of Chile. Using representatives' assessments from 406 RWS regarding the need for the replacement of several components of their system's infrastructure, an index of infrastructure conditions was constructed and subjected to a cluster analysis that identified three dissimilar groups of RWS. The top condition cluster represents a reference group (benchmark) that exhibits the highest scores in water quality, quantity, and delivery reliability, which highlights the association between infrastructure conditions and performance outcomes. In addition, a comparison of RWS attributes of these three clusters allowed us to characterize them in terms of structural, organizational, management, and environmental variables. This study sheds light on the role of RWS infrastructure in enabling these organizations to deliver high-quality service, and the findings serve to guide policy actions and tailored planning. The methodology presented here can be applied in other regions beyond that of the case study because it represents a low-cost tool to measure the infrastructure condition of RWS based on representatives' assessments and is an effective and practical way to distinguish RWS most in need of support. © 2024 American Society of Civil Engineers. | |
| Atmospheric River Brings Warmth and Rainfall to the Northern Antarctic Peninsula During the Mid-Austral Winter of 2023 | Geophysical Research Letters | Bozkurt, D.; Carrasco, J.; Cordero, R.; Fernandoy, F.; Gómez-Contreras, A.; Carrillo, B.; Guan, B. | 2024 | Zonas Costeras | 10.1029/2024GL108391 | https://doi.org/10.1029/2024GL108391 | arte2024GL108391 | Vol: 51.0 Issue: 13.0 | 00948276 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Contrasting the extensive research on summer atmospheric rivers (ARs) in the Antarctic Peninsula (AP), winter AR impacts are less understood. This study examines a unique warming event from 1 to 3 July 2023, using in situ winter observations and ERA5 reanalysis. On 2 July, Frei station experienced an extreme warm event with a temperature of 2.7°C and a significant rise in the freezing level, coinciding with winter rainfall. A pressure dipole pattern over the AP, with contrasting circulations over Bellingshausen and Weddell Seas, facilitated an AR, carrying warm, humid air initially from South America/Atlantic and then the southeast Pacific. This shift resulted in anomalous water stable isotope composition in precipitation. Trends suggest a strengthening winter pressure dipole, associated with increased AR frequency and higher temperatures in northern AP. These findings highlight the importance of winter observations in exploring AR impacts, bridging knowledge gaps about winter AR behaviors. © 2024. The Author(s). |
| Atmospheric blocking and temperatures in the Antarctic Peninsula | Science of the Total Environment | Bozkurt, D.; Marín, J.; Verdugo, C.; Barrett, B. | 2024 | Zonas Costeras | 10.1016/j.scitotenv.2024.172852 | https://doi.org/10.1016/j.scitotenv.2024.172852 | art172852 | Vol: 931.0 | 00489697 | Thomson Reuters ISI (SCIE) | English | The Antarctic Peninsula (AP) has displayed a propensity for persistent blocking ridges and anticyclonic conditions, particularly during recent summertime extreme weather events. This study investigates atmospheric blocking patterns over the AP through historical (1981–2010) and future (2071–2100, SSP5–8.5) periods using ERA5 reanalysis and six CMIP6 models, including multi-member realizations from two models totaling ten simulations. We focus particularly on 500 hPa geopotential height (Z500) and near-surface air temperature (T2m) anomalies. The historical analysis highlights significant differences between the CMIP6 models and ERA5 reanalysis, especially in the austral winter, with EC-Earth3 and INM-CM4 models matching closest with the ERA5. Future projections show that while the northern AP and the Drake Passage largely do not exhibit a clear trend towards increased blocking, there are exceptions. The EC-Earth3 model predicts more blocking–like conditions northwest of the AP in summer and a pronounced ridge over the Bellingshausen Sea in winter, indicating a potential increase in blocking events. The INM-CM4 model projects a minor increase in summer Z500 heights off the western and southern AP, without clear blocking patterns over the AP, and negligible winter changes. Localized intensification is noted in the northern parts of the blocking domain and southern AP during extreme blocking conditions. These variations are mirrored in T2m anomalies, suggesting warming in the northern and southern sections of AP but little change elsewhere. The results of this study underscore the need to more accurately capture complex blocking mechanisms and their impacts on regional climate patterns around the AP. We also suggest employing refined blocking definitions and incorporating a broader range of climate models to enhance our understanding of blocking patterns and their impacts in a changing climate. © 2024 Elsevier B.V. | |
| Evaluating the ability of convolutional neural networks for transfer learning in Pinus radiata cover predictions | Ecological Informatics | Bravo-Diaz, A.; Moreno, S.; Lopatin, J. | 2024 | Cambio de Uso de Suelo | 10.1016/j.ecoinf.2024.102684 | https://doi.org/10.1016/j.ecoinf.2024.102684 | art102684 | Vol: 82.0 | 15749541 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The species Pinus radiata is highly invasive in native forests in Chile, drastically affecting the functioning and structure of ecosystems. Hence, it is imperative to develop robust approaches to detect P. radiata invasions at different scales. Models based on convolutional neural networks (CNN) have proven to be a promising alternative to detect plant invasions in high-resolution remote sensing data, such as those obtained by drones. However, studies have been limited in their spatial variability and their assessments of transferability or transfer learning to new sectors, hindering the ability to use these models in a real-world setting. We train models based on CNN architectures using unpiloted aerial vehicle data and evaluate their ability to transfer learning outside the training domain using regression approaches. We compared models trained with low spatial variability (mono-site) with those with high spatial variability (multi-site). We further sought to maximize the transference of learning outside the training domain by searching among different architectures and models, maximizing the evaluation in an independent data set. The results showed that transfer learning is better when multi-site models with higher spatial variability are used for training, obtaining a coefficient of determination R2 between 60% and 87%. On the contrary, mono-site models present a wide variability of performance attributed to the dissimilarity of information between sites, limiting the possibilities of using these models for extrapolations or model generalizations. We also obtained a significant difference between within-domain generalization using test data versus transfer learning outside the training domain, showing that testing data alone cannot depict such discrepancy without further data. Finally, the best models for transfer learning on new data domains often do not agree with those selected by the standard training/validation/testing scheme. Our findings pave the way for deeper discussions and further investigations into the limitations of CNN models when applied to high-resolution imagery. © 2024 |
| Characterization of Multi-Decadal Beach Changes in Cartagena Bay (Valparaíso, Chile) from Satellite Imagery | Remote Sensing | Briceño de Urbaneja, I.; Pardo-Pascual, J.; Cabezas-Rabadán, C.; Aguirre, C.; Martínez, C.; Pérez-Martínez, W.; Palomar-Vázquez, J. | 2024 | Zonas Costeras | 10.3390/rs16132360 | https://doi.org/10.3390/rs16132360 | art2360 | Vol: 16.0 Issue: 13.0 | 20724292 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Sandy coastlines are very dynamic spaces affected by a variety of natural and human factors. In Central Chile, changes in oceanographic and wave conditions, modes of inter-annual climate variability such as El Niño Southern Oscillation (ENSO), and extreme events such as earthquakes and tsunamis condition the beach morphology. At the same time, direct human actions alter the arrival of sediments to the coast and their alongshore distribution. Despite the relevance of the beaches for this coastal region and the interesting relationship their morphology has with the aforementioned factors, there is a lack of robust morphological datasets to provide a deep characterization and understanding of the dynamism of the Chilean coast. Based on the information provided by satellite-derived shorelines (SDSs) defined by using the SHOREX algorithm, this paper characterizes the morphological changes of Playa Grande in Cartagena Bay (Central Chile) during the period 1985–2019. The shoreline position data are analyzed in the context of changing beach transforming elements, allowing for a better understanding of the changes according to multiple drivers. While some of these factors, such as earthquakes or coastal storms, have a punctual character, changes in wave patterns vary at different time scales, from seasonal to multi-annual, linked to climate phases such as ENSO. Its effects are translated into shoreline erosion and accretion conditioned by the morphology and orientation of the coast while influenced by the availability of sediment in the coastal system. According to that, a conceptual model of the dynamism and redistribution of sediment in the Bay of Cartagena is proposed. The work proves the high utility that the systematic analysis of multi-decadal SDS datasets obtained from the images acquired in the optical by the Landsat and Sentinel-2 offer for beach monitoring and understanding the coastal dynamism. © 2024 by the authors. |
| Vegetation and environmental responses from extreme glacial to extreme interglacial conditions in central Isla Grande de Chiloé (∼42°S), northwestern Patagonia | Quaternary Science Reviews | Briones, D.; Guerra, L.; Soteres, R.; Moreno, P. | 2024 | Agua y Extremos | 10.1016/j.quascirev.2024.108927 | https://doi.org/10.1016/j.quascirev.2024.108927 | art108927 | Vol: 344.0 | 02773791 | Thomson Reuters ISI (SCIE) | English | We examine the vegetation and environmental evolution of central Isla Grande de Chiloé (IGC), northwestern Patagonia (NWP), spanning the two climatic endmembers of the last glacial-interglacial cycle: the Last Glacial Maximum (LGM) and the Early Holocene (EH). Our results from Lago Auquilda show Evergreen Subantarctic forests interspersed with Magellanic Moorland during the early LGM (∼30.9-26.1 ka), followed by species-poor closed-canopy Nothofagus forests with low conifer abundance and absence of Magellanic Moorland during the late LGM (∼18.9-17.9 ka). Initial canopy fragmentation at ∼17.9 ka gave way to rapid densification and diversification of trees, herbs, and vines characteristic of North Patagonian rainforests (NPRF), marking the onset of the Last Glacial Termination (T1). Closed-canopy NPRF established between ∼15.5-14.8 ka, followed by mixed forests with shade- and cold-tolerant hygrophilous NPRF conifers until abrupt increases in shade-intolerant trees favored by local fires between ∼12.6-11.4 ka. NPRF conifers disappeared as thermophilous species of the Valdivian rainforest and fire activity increased between ∼11.4-8.7 ka. We interpret that temperate rainforest inhabited the periphery of the Patagonian Ice Sheet in NWP under cold and hyperhumid conditions during the LGM. Precipitation was highest in the early LGM, declined during the late LGM, diminished to an early T1 minimum between ∼17.1-16.4 ka, and then increased steadily to a maximum between ∼14.8-12.6 ka, overlapping with the Antarctic Cold Reversal (ACR). Subsequent declines at ∼12.6 ka and ∼11.4 ka led to extreme warm-dry conditions during the EH with intense fire activity. Hyperhumid conditions during the LGM and ACR imply equatorward-shifted Southern Westerly Winds (SWW), minimum precipitation during the early portion of T1 relates to poleward-shifted SWW, and the EH warm-dry phase reflects a zonally symmetric decline in SWW intensity. Our Lago Auquilda record replicates the timing and structure of changes revealed by multiple paleoclimate studies throughout western Patagonia which, in turn, are synchronous/coherent with key southern mid- and high-latitude records. © 2024 Elsevier Ltd | |
| Adaptation strategies of giant viruses to low-temperature marine ecosystems | The ISME Journal | Buscaglia, M.; Iriarte, J.; Schulz, F.; Díez, B. | 2024 | Zonas Costeras | 10.1093/ismejo/wrae162 | https://doi.org/10.1093/ismejo/wrae162 | wrae162 | 1751-7370 | Thomson Reuters ISI (SCIE) | https://creativecommons.org/licenses/by/4.0/ | en | ||
| The implicit market price of soil erosion: An estimation using a hedonic model with spatial spillovers | Agricultural Economics (United Kingdom) | Caffera, M.; Lavín, F.; Barrientos, M.; Anza, D.; Carrasco-Letelier, L. | 2024 | Cambio de Uso de Suelo | 10.1111/agec.12857 | https://doi.org/10.1111/agec.12857 | 01695150 | Thomson Reuters ISI (SCIE; SSCI) | English | We estimate the implicit market price of soil erosion using quarterly data of 2824 agricultural farms traded in Uruguay between 2000 and 2014. A unique feature of our estimation is that we allow for possible spatial spillovers. We find evidence of a negative and statistically significant association between erosion and land values. On average, an additional loss of 1% of the original topsoil due to erosion is associated with a direct (own) decrease of.24% in the per-hectare price of agricultural land (P-value:.012, 95% CI: −.0042, −.0005). In 2023 dollars, this is equivalent to a decrease of USD 8.7 in the average price per hectare, or USD 1130 in the price of the average farm. In terms of tons of soil, the average value is $.24 a ton. Finally, considering the 50 km radius of our spatial model, the value of losing 1% of topsoil is $15.8 million. The value of our estimates is sensitive to our measure of erosion and our specification of the spatial-temporal weighting matrix, but the statistical association is robust. © 2024 International Association of Agricultural Economists. | |||
| Women gatherers of nalca (Gunnera tinctoria) as guardians of socioecosystems: Local history, extractivism and restoration in Chile | Extractive Industries and Society | Cameron, J.; Vergara-Pinto, F.; Carrasco Henríquez, N.; Neves, C.; de Cortillas, N.; Flores, C. | 2024 | Zonas Costeras | 10.1016/j.exis.2023.101394 | https://doi.org/10.1016/j.exis.2023.101394 | art101394 | Vol: 17.0 | 2214790X | Thomson Reuters ISI (SSCI) | English | In the coastal areas of southern Chile, an interdependence exists between gatherers and the nalca ecosystem known as “pajonal” (swampy spaces), as it provides livelihoods for families and gatherers work to restore and maintain the pajonales. However, the forestry industry has left significant parts of these ecosystems within their margins, impacting their distribution. In this regard, little attention has been paid to the effects of nalca decline on the lives of gatherers and their community responses. Through a historical and ethnographic approach, this paper aims to examine the trajectory followed by women gatherers of the "Agrupación Nalqueros de Pehuén'' in Lebu (Arauco Province, Chile), who have dedicated themselves to the care of socio-ecosystems amidst the globalisation of forest industry and certification process. The results revealed a historical trajectory of nalca gathering marked by interscalar processes that led to governance practices in the interstices of an imposed monocultural geography. In response, the group has resisted and made efforts to achieve the restoration of pajonales amidst forest extractivism. Caring for the nalcas involves territorialising the pajonal and redefining it in accordance with ethical and ecological principles adopted over time for the well-being of their community and the commons they care for. © 2023 Elsevier Ltd | |
| Economic valuation of Harmful Algal Blooms (HAB): Methodological challenges, policy implications, and an empirical application | Journal of Environmental Management | Carias, J.; Vásquez-Lavín, F.; Barrientos, M.; Ponce Oliva, R.; Gelcich, S. | 2024 | Cambio de Uso de Suelo | 10.1016/j.jenvman.2024.121566 | https://doi.org/10.1016/j.jenvman.2024.121566 | art121566 | Vol: 365.0 | 03014797 | Thomson Reuters ISI (SCIE) | English | This paper presents a literature review on the economic valuation of Harmful Algal Bloom (HAB) impacts, identifying methodological challenges, policy implications, and gaps. Unlike previous literature reviews, we are particularly interested in determining whether the economic valuations of HABs have included a policy analysis. Our paper provides a conceptual framework that allows us to evaluate whether applications of economic studies of HABs are consistent with a well-defined economic welfare analysis. It links methodologies and techniques with welfare measures, data types, and econometric methods. Based on this literature review, we present an example of economic valuation that closes the gap between policy analysis and valuation methodology. We use a stated preferences study to estimate a “seafood price premium” to create a fund to support monitoring systems and for damage compensation to producers in the presence of HABs. Results show that most economic studies on HAB valuation do not consider any cost-benefit analysis of a defined policy intervention. The predominant economic valuation methodology uses market information to estimate a proxy for welfare measure of the impact of HABs (loss revenue, sales, exports). Moreover, nonuse and indirect use values are ignored in the literature, while stated preference methodologies are underrepresented. Finally, results from 1293 surveys found that people are willing to pay an increase in the price of mussels to support a policy that informs on HAB. However, the lack of institutional trust affects the probability of paying negatively. © 2024 Elsevier Ltd | |
| Indigenous Knowledge in Post-Pandemic Cultural Tourism: Discussion from Arauco Territories, Chile | Heritage | Carrasco Henríquez, N.; Cid Aguayo, B.; Neves Guzmán, C.; Orellana Ojeda, J. | 2024 | Zonas Costeras | 10.3390/heritage7020040 | https://doi.org/10.3390/heritage7020040 | 829-843 | Vol: 7.0 Issue: 2.0 | 25719408 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | In the last two decades, cultural tourism has transformed the aesthetics and the relationship between the actors of the Arauco territories. In the post-COVID context, these transformations could be reinforced, especially considering the actual legal scenario about indigenous rights and the global ecological crisis. In most cases, the indigenous people, with cultural tourism initiatives, highlight their world vision, including the relations with nature. For this reason, we propose to study this scientific problem from the relational ontology perspective. In this study, we describe the situation of cultural tourism in Arauco Province, Chile, where Mapuche people, the Chilean State, and the international market coexist in permanent friction. The main objective is to analyze how the pandemic influenced Mapuche cultural tourism, from the Mapuche cultural perspective and the global conditions for their development. The methods of research mixed historical and ethnographic approaches with a sample of key actors of Mapuche cultural tourism. As results, we can show the Mapuche way of understanding cultural tourism and the new conditions derived from the pandemic and post-pandemic contexts. © 2024 by the authors. |
| The key role of extreme weather and climate change in the occurrence of exceptional fire seasons in south-central Chile | Weather and Climate Extremes | Carrasco-Escaff, T.; Garreaud, R.; Bozkurt, D.; Jacques-Coper, M.; Pauchard, A. | 2024 | Agua y Extremos; Zonas Costeras | 10.1016/j.wace.2024.100716 | https://doi.org/10.1016/j.wace.2024.100716 | art100716 | Vol: 45.0 | 22120947 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Unprecedentedly large areas were burned during the 2016/17 and 2022/23 fire seasons in south-central Chile (34-39°S). These seasonal-aggregated values were mostly accounted for human-caused wildfires within a limited period in late January 2017 and early February 2023. In this paper, we provide a comprehensive analysis of the meteorological conditions during these events, from local to hemispheric scales, and formally assess the contribution of climate change to their occurrence. To achieve this, we gathered monthly fire data from the Chilean Forestry Corporation and daily burned area estimates from satellite sources. In-situ and gridded data provided near-surface atmospheric insights, ERA5 reanalysis helped analyze broader wildfire features, high-resolution simulations were used to obtain details of the wind field, and large-ensemble simulations allowed the assessment of climate change's impact on extreme temperatures during the fires. This study found extraordinary daily burned area values (>65,000 ha) occurring under extreme surface weather conditions (temperature, humidity, and winds), fostered by strong mid-level subsidence ahead of a ridge and downslope winds converging towards a coastal low. Daytime temperatures and the water vapor deficit reached the maximum values observed across the region, well above the previous historical records. We hypothesize that these conditions were crucial in exacerbating the spread of fire, along with longer-term atmospheric processes and other non-climatic factors such as fuel availability and increasing human-driven ignitions. Our findings further reveal that climate change has increased the probability and intensity of extremely warm temperatures in south-central Chile, underscoring anthropogenic forcing as a significant driver of the extreme fire activity in the region. © 2024 The Authors |
| Climate and ice sheet dynamics in Patagonia throughout marine isotope stages 2 and 3 | Climate of the Past | Castillo-Llarena, A.; Retamal-Ramírez, F.; Bernales, J.; Jacques-Coper, M.; Prange, M.; Rogozhina, I. | 2024 | Zonas Costeras | 10.5194/cp-20-1559-2024 | https://doi.org/10.5194/cp-20-1559-2024 | 1559-1577 | Vol: 20.0 Issue: 7.0 | 18149324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | During the Last Glacial Maximum (LGM, ∼23 000 to 19 000 years ago), the Patagonian Ice Sheet (PIS) covered the central chain of the Andes between ∼38 to 55° S. Existing paleoclimate evidence-mostly derived from glacial landforms-suggests that maximum ice sheet expansions in the Southern Hemisphere and Northern Hemisphere were not synchronized. However, large uncertainties still exist in the timing of the onset of regional deglaciation and its major drivers. Here we present an ensemble of numerical simulations of the PIS during the LGM. We assess the skill of paleoclimate model products in reproducing the range of atmospheric conditions needed to enable an ice sheet growth in concordance with geomorphological and geochronological evidence. The resulting best-fit climate product is then combined with records from southern South America offshore sediment cores and Antarctic ice cores to drive transient simulations throughout the last 70 ka using a glacial index approach. Our analysis suggests a strong dependence of the PIS geometry on near-surface air temperature forcing. Most ensemble members underestimate the ice cover in the northern part of Patagonia, while tending to expand beyond its constrained eastern boundaries. We largely attribute these discrepancies between the model-based ice geometries and geological evidence to the low resolution of paleoclimate models and their prescribed ice mask. In the southernmost sector, evidence suggests full glacial conditions during marine isotope stage 3 (MIS3, ∼59 400 to 27 800 years ago), followed by a warming trend towards MIS2 (∼27 800 to 14 700 years ago). However, in northern Patagonia, this deglacial trend is absent, indicating a relatively consistent signal throughout MIS3 and MIS2. Notably, Antarctic cores do not reflect a glacial history consistent with the geochronological observations. Therefore, investigations of the glacial history of the PIS should take into account southern midlatitude records to capture effectively its past climatic variability. © Copyright: 2024 Andrés Castillo-Llarena et al. |
| Vertically distinct sources modulate stable isotope signatures and distribution of Mesozooplankton in central Patagonia: The Golfo de Penas - Baker Channel connection and analogies with the Beagle Channel | Journal of Marine Systems | Castro, L.; Soto-Mendoza, S.; Riccialdelli, L.; Presta, M.; Barrientos, P.; González, H.; Daneri, G.; Gutiérrez, M.; Montero, P.; Masotti, I.; Díez, B. | 2024 | Zonas Costeras | 10.1016/j.jmarsys.2023.103892 | https://doi.org/10.1016/j.jmarsys.2023.103892 | 103892 | Vol: 241.0 | 0924-7963 | Thomson Reuters ISI (SCIE) | en | Using hydrographic and zooplankton sampling along with stable isotope analyses, we determined the influence of freshwater input and of oceanic water ingress at the Golfo de Penas to the Baker Channel (47°S), central Patagonia, on the zooplankton community during mid-spring. Our results show that different taxonomic and functional groups occurred within the mesozooplankton community along an offshore-inshore-oriented transect. Some groups occurred mostly offshore (i.e. euphausiids, fish larvae, stomatopods, amphipods), while others occurred in higher abundance inshore (i.e. medusae, chaetognaths, siphonophores, ostracods). Early life stages of ecologically key species, such as Euphausia vallentini and pelagic stages of Munida gregaria, occurred mostly at the Golfo de Penas. Higher trophic positions estimated from δ15N occurred in mesozooplankton groups inshore (Baker Channel) and lower at the Golfo de Penas, coinciding with the decrease in C:N ratio in zooplankton and with an increase in chlorophyll-a values in the seawater seawards. The δ13C distribution in the zooplankton groups along the offshore-inshore transect showed a positive gradient from the inshore most stations towards the Baker Channel mouth, suggesting a negative relationship with freshwater carrying terrestrial organic carbon and a positive relationship with seawater. However, from the channel mouth seawards, a decrease in δ13C in most zooplankton groups occurred. Within the Baker Channel, low δ13C values occurred in particulate organic matter (POM) at the surface layer, higher values at intermediate depths, and low values at the deepest zones. This uneven distribution of δ13C values in POM and zooplankton, along with the presence of different water masses at different depths suggest an along-basin transport of organic carbon of different sources at different layers: of terrestrial origin at surface, marine origin at mid depth, and from degraded organic matter from offshore entering at higher depths. Thus, a complex scenario of lateral transport of water of different characteristics modulates the presence of zooplankton in different locations and their food sources along the area. These findings resemble others observed in further south in the Beagle Channel (57°S) also in spring but the relative contribution of different carbon sources may differ between Patagonian systems. © 2023 Elsevier B.V. | |
| Estimating Residential Water Demand Under Systematic Shifts Between Uniform Price (UP) and Increasing Block Tariffs (IBT) | Water Resources Research | Chovar Vera, A.; Vásquez-Lavín, F.; Ponce Oliva, R. | 2024 | Cambio de Uso de Suelo | 10.1029/2022WR033508 | https://doi.org/10.1029/2022WR033508 | arte2022WR033508 | Vol: 60.0 Issue: 4.0 | 00431397 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | We evaluate whether changing from a uniform price (UP) to an increasing block tariff (IBT) changes people's behavior. We exploit a unique setting in which the price scheme moves back and forth yearly from UP to IBT. We discuss the effectiveness of IBT in reducing summer consumption. This issue is relevant to many countries and policymakers interested in designing tariff structures. There is no evidence of how the same consumer may react to systematically switching from one tariff structure to another yearly. We estimate the residential water demand and its price elasticity using a generalized least squared random effect model for the UP and the discrete/continuous choice model for the IBT. In addition, we split the sample between low and high-consumption groups. For the low consumption group unaffected by the tariff change, the elasticity in the nonsummer months is higher (more elastic) than in the summer. Consumers in this group reduce their elasticity from nonsummer to summer months (−0.299 vs. −0.071, respectively) and increase their consumption by 13%. The high consumption group increased its summer consumption, but only by 8.7%, and contrary to the first group, its elasticity increased significantly (from −0.299 to −0.568). The high-consumption group is indeed affected by the change in tariff. From a policy perspective, this implies that the IBT structure is relevant. However, if the policy seeks to promote conservation, it needs to be adjusted to a lower decile of the water consumption distribution to affect a more significant portion of the population. © 2024. The Authors. |
| Engaging diverse knowledge holders in adaptation research | Nature Climate Change | Cundill, G.; Harvey, B.; Ley, D.; Singh, C.; Huson, B.; Aldunce, P.; Biesbroek, R.; Lawrence, J.; Morchain, D.; Nalau, J.; Simpson, N.; Totin, E. | 2024 | Agua y Extremos | 10.1038/s41558-024-02056-5 | https://doi.org/10.1038/s41558-024-02056-5 | 662-664 | Vol: 14.0 Issue: 7.0 | 1758678X | Thomson Reuters ISI (SCIE; SSCI) | en | Adaptation evidence and knowledge are diverse and unequally represented in global adaptation discourse. The Adaptation Futures 2023 conference sought to bring this diversity together to advance more inclusive and impactful adaptation science, and confronted both the benefits and the trade-offs that this effort entails. |
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| Unveiling emerging interdisciplinary research challenges in the highly threatened sclerophyllous forests of central Chile | Revista Chilena de Historia Natural | Delpiano, C.; Vargas, S.; Ovalle, J.; Cáceres, C.; Zorondo-Rodríguez, F.; Miranda, A.; Pohl, N.; Rojas, C.; Squeo, F. | 2024 | Cambio de Uso de Suelo | 10.1186/s40693-024-00130-y | https://doi.org/10.1186/s40693-024-00130-y | art7 | Vol: 97.0 Issue: 1.0 | 0716078X | Thomson Reuters ISI (SCIE) | English | Background: The potential ecosystem collapse of forests in Mediterranean-type ecosystems (MTEs) by unprecedented droughts is worrisome due to the impacts on its exceptional biodiversity and human well-being. However, research integrating the impacts of global change drivers, forest resilience and the challenges facing human-nature relationships is still scarce. Methods and results: Using the central Chile megadrought and recently massive forest browning event as a model scenario, we identified, through a scientific literature review and an interdisciplinary scientific workshop, the research priorities and questions to address for MTEs in a context of global change. Our results highlighted knowledge gaps that need to be covered, particularly in social and environmental sciences, with an emphasis on soil science. Research priorities must focus on (1) the understanding of interactive effects of global and local anthropogenic drivers on MTEs and (2) the evaluation of the potential impacts of MTEs collapse on human well-being and ecosystem functioning. Conclusions: We highlight the need for a collaborative approach involving scientists, landowners, managers/administrators, and policymakers to apply adaptive forest management against the current socio-environmental challenges under a global change context. © The Author(s) 2024. | |
| Advancing South American Water and Climate Science through Multidecadal Convection-Permitting Modeling | Bulletin of the American Meteorological Society | Dominguez, F.; Rasmussen, R.; Liu, C.; Ikeda, K.; Prein, A.; Varble, A.; Arias, P.; Bacmeister, J.; Bettolli, M.; Callaghan, P.; Carvalho, L.; Castro, C.; Chen, F.; Chug, D.; Chun, K.; Dai, A.; Danaila, L.; da Rocha, R.; de Lima Nascimento, E.; Dougherty, E.; Dudhia, J.; Eidhammer, T.; Feng, Z.; Fit... | 2024 | Zonas Costeras | 10.1175/BAMS-D-22-0226.1 | https://doi.org/10.1175/BAMS-D-22-0226.1 | E32-E44 | Vol: 105.0 Issue: 1.0 | 00030007 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | |
| Land Management Drifted: Land Use Scenario Modeling of Trancura River Basin, Araucanía, Chile | Land | Díaz-Jara, A.; Manuschevich, D.; Grau, A.; Zambrano-Bigiarini, M. | 2024 | Agua y Extremos | 10.3390/land13020157 | https://www.mdpi.com/2073-445X/13/2/157 | 157 | Vol: 13.0 Issue: 2.0 | 2073-445X | Thomson Reuters ISI (SSCI) | All Open Access; Gold Open Access | English | Modeling land use scenarios is critical to understand the socio-environmental impacts of current decisions and to explore future configurations for management. The management of regulations and permits by central and local governments plays an important role in shaping land use, with different complexities arising from site-specific socioeconomic dynamics. In Chile, the complexity is even more evident due to insufficient binding land regulations, fragmented government procedures, and the primacy of cities over rural areas. Yet land use must be managed to support sustainable development. This research integrates several state management dynamics into scenario modeling to support decision making at the basin scale through 2050. We employed a mixed qualitative-quantitative approach using interviews with state officials and local stakeholders as the basis for the Conversion of Land Use and its Effects (CLUE) model, which resulted in three scenarios with spatially explicit maps. Key findings indicate that opportunities for developing normative planning tools are limited, leaving state management without clear direction. However, current management practices can address problematic activities such as second-home projects and industrial monocultures while promoting small-scale agriculture. Scenario modeling is useful for understanding how the specifics that arise from the scalar dynamics of state management affect land use change and how existing management resources can be leveraged to achieve positive outcomes for both the ecosystem and society. |
| Impact of atmospheric rivers on the winter snowpack in the headwaters of Euphrates-Tigris basin | Climate Dynamics | Ezber, Y.; Bozkurt, D.; Sen, O. | 2024 | Zonas Costeras | 10.1007/s00382-024-07267-2 | https://doi.org/10.1007/s00382-024-07267-2 | 09307575 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Understanding the hydrometeorological impacts of atmospheric rivers (ARs) on mountain snowpack is crucial for water resources management in the snow-fed river basins such as the Euphrates-Tigris (ET). In this study, we investigate the contribution of wintertime (December-January–February) ARs to precipitation and snowpack in the headwater regions of the ET Basin for the period of 1979–2019 using a state-of-the-art AR catalog and ERA5 reanalysis data. The results show that AR days in the headwaters region could be warmer by up to 3 °C and wetter by over 5 mm day−1 compared to non-AR days. The contribution of ARs to the total winter precipitation varies from year to year, with a maximum contribution of over 80% in 2010 and an average contribution of 60% over the 40-year period. While snow accumulation on AR days shows spatial variability, the average snow contribution is 27% of the seasonal average, ranging from 12 to 57% for different years. The south-facing parts of the mountain range experience significant snowmelt, with contributions ranging from 15 to 80% for different years. The high total precipitation (60%) and low snowpack (27%) contribution can be attributed to the semi-arid characteristics of the region and the occurrence of rain-on-snow events, where rain falling on existing snow rapidly melts the snowpack. The findings have implications for water resource management and call for continued research to improve our knowledge of ARs and their interactions with the complex terrain of the ET Basin. © The Author(s) 2024. | ||
| Time series measurements of dissolved nitrous oxide, nutrients, and chlorophyll at stations in the South Shetland Islandshttps: | Farias, L.; Alcaman Arias, M. | 2024 | Zonas Costeras | doi.pangaea.de/10.1594/PANGAEA.969584 | https://doi.org/doi.pangaea.de/10.1594/PANGAEA.969584 | Pangaea | The data set comprises concentrations of dissolved nitrous oxide (N2O), an important green house gas, d nutrients and chlorophyll-a from surface ocean. Seawater samples collected in a time series stations located in Greenwich Island within the South Shetland Islands, an area n of the western Antarctic Peninsula influenced by the circumpolar current system and adjacent to Bellinghausen. Two specific marine sampling points (Station P1: -62,489S; -59,683W and station P3: -62,461; -59,677 W) were monitored over four late summer periods (February and early March) in the years 2017, 2018, 2019, and 2020. Physical variables were measured with a Conductivity Temperature Depth profiler (CTD; SeaBird19 plus). Seawater samples for biological and biogeochemical variables were superficially collected at a depth of 2, 5 or 10 meters using a handheld pump or Niskin bottles (5 and 10 m depth) aboard a Zodiac boat for nitrous oxide, nutrient, and chlorophyll analysis. Simultaneously, a CTD instrument was deployed to obtain temperature (°C) and salinity profiles. For chlorophyll a (Chl-a) measurements, triplicate 1-L samples of seawater from both 2 and 30 m depth were prefiltered with a 150-µm net to exclude large organisms, and then the remaining biomass was collected by subsequent filtration with 0.7-µm GF/F glass fiber filters. Each filter was frozen until processing, using acetone extraction protocols, after which extracts were analyzed by fluorometric (measured with a 10-AU Turner fluorometer (Turner, USA). ([Holm-Hansen & Riemann, 1978] techniques, respectively. Samples for the determination of inorganic nutrients (nitrite (NO2−), nitrate (NO3−) and phosphate (PO43−)) were also taken in triplicate stored in 15 mL polyethylene tubes and frozen at −20 °C in the dark until analysis. NO2−, NO3− and PO4−3 concentrations were measured with a Seal AutoAnalyzer 3 (AA3, SEAL Analytical, Mequon, WI, USA) [Grashoff et al., 2009]. N2O samples were taken in triplicate in 20 mL vials and carefully sealed to avoid air bubbles. They were then preserved with 50 μL of saturated HgCl2 and stored in darkness until analysis. N2O was analyzed by creating a 5 mL headspace of ultrapure Helium (He) and then equilibrated within the vial and measured by gas chromatography (Shimadzu 17A) using an electron capture detector (ECD). The calibration curves were made before each measurement with five points using pure He, 0.1, 0.5, and 1 of N2O standards and dry air (Farias et al., 2015). The ECD detector linearly responded to this concentration range and the analytical error for N2O measurements was ~3%. The uncertainty of the measurements was calculated from the standard deviation of the triplicate measurements by depth. Samples with a variation coefficient above 10% were not considered in the N2O database. Procedures of calibration were used following Wilson et al. (2018) | ||||||
| Vertical profiles of nitrous oxide, methane and nutrients in the Passage Drake during RV METEOR cruise M179 | Farias, L.; Tenorio, S.; Verdugo, J.; Sanzana, K.; Krock, B. | 2024 | Zonas Costeras | doi.org/10.1594/PANGAEA.971359 | https://doi.org/doi.org/10.1594/PANGAEA.971359 | Pangaea | The Drake Passage is the narrowest constriction of the Antarctic Circumpolar Current (ACC), which connects the Atlantic, Pacific, and Southern Oceans. This region significantly influences global ocean circulation, climate patterns, and the distribution of marine species. Additionally, the strong currents and turbulent waters of the Drake Passage provide valuable insights into ocean mixing processes and their role in heat and greenhouse gas exchanges with the atmosphere. Dissolved nitrous oxide (N2O), and methane (CH4) were sampled during the M179/2 FjordFlux cruise, conducted aboard the German research vessel METEOR, between January 14th and February 14th, 2022. The southern Patagonian Cold Estuarine System (PCES; 54°S), including the Drake Passage (DP; 60°S), was covered. From a total of 41 stations, we present data from 8 stations covering the DP. These stations include vertical profiles of gases such as CH4, N2O and nutrients (NO3-, NO2-, PO43-). Vertical profiles of temperature and salinity were obtained with a CTD profiler SBE3 and SBE4 respectively, only at 0m, T and S were obtained with a Salinometer YSI 30. Water samples at different depths were collected using Niskin bottles attached to a rosette for gas determination (CH4 and N2O); 20 mL of water were taken in triplicate in a glass vials, and 50 μL of saturated HgCl2 were added to preserve them. The vials were carefully sealed with rub and aluminum caps to avoid contamination with the atmosphere, then stored in darkness until analysis in the laboratory. N2O and CH4 were analyzed manually using the phase equilibrium method (McAuliffe, 1963) by creating a 5 mL headspace of ultrapure helium and equilibrating for 1h at 30°C. Mesurements were carried out through gas chromatography using an Electron Capture Detector (Shimadzu 17A) and Flame Ionization Detector (Agilent technologies 6850), respectively. A Restek Rt-QS- Bond column (30 m length, 0.53 mm inner diameter, 20 μm film thickness) was employed, maintained at a temperature of 30 °C with a flow of 2.6 mL min−1 using He as an ultra- pure gas carrier. For both gasses, a 5-point calibration curve was developed: He (as ~0 value) and four standard gas mixtures (Scott Mini-Mix, from Air Liquide) concentrations of 0.25, 0.35, 0.55 and 1 ppm for N2O and 1, 2.5, 5, and 10 ppm concentrations for CH4. The uncertainty of the measurements was calculated from the standard deviation of the triplicate measurements by depth. Samples with a variation coefficient above 10% were not considered. The solubility equations based on the in situ T and S of Wiesenburg and Guinasso (1979) and Weiss and Price (1980), were used to calculate N2O and CH4 concentrations. Once the gases were analyzed, the sample (15mL) was analyzed for nutrients trough a SealAA3 segmented flow auto-analyzer, using standard colorimetric techniques (Grasshoff et al., 1983). This analyser had 4 different channels, equipped with specific modules for each nutrient (including silicates) and delivers the final concentration. The detection limit for every nutrient were NO3- (0.015 – 67.5 μM), NO2- (0.015 – 7.5 μM), PO43- (0.010 – 4.5 μM). | ||||||
| Understanding the impacts of coastal deoxygenation in nitrogen dynamics: an observational analysis | Scientific Reports | Farias, L.; de la Maza, L. | 2024 | Zonas Costeras | 10.1038/s41598-024-62186-w | https://doi.org/10.1038/s41598-024-62186-w | art11826 | Vol: 14.0 Issue: 1.0 | 20452322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Biological production and outgassing of greenhouse gasses (GHG) in Eastern Boundary Upwelling Systems (EBUS) are vital for fishing productivity and climate regulation. This study examines temporal variability of biogeochemical and oceanographic variables, focusing on dissolved oxygen (DO), nitrate, nitrogen deficit (N deficit), nitrous oxide (N2O) and air-sea N2O flux. This analysis is based on monthly observations from 2000 to 2023 in a region of intense seasonal coastal upwelling off central Chile (36°S). Strong correlations are estimated among N2O concentrations and N deficit in the 30–80 m layer, and N2O air-sea fluxes with the proportion of hypoxic water (4 < DO < 89 µmol L−1) in the water column, suggesting that N2O accumulation and its exchange are mainly associated with partial denitrification. Furthermore, we observe interannual variability in concentrations and inventories in the water column of DO, nitrate, N deficit, as well as air-sea N2O fluxes in both downwelling and upwelling seasons. These variabilities are not associated with El Niño-Southern Oscillation (ENSO) indices but are related to interannual differences in upwelling intensity. The time series reveals significant nitrate removal and N2O accumulation in both mid and bottom layers, occurring at rates of 1.5 µmol L−1 and 2.9 nmol L−1 per decade, respectively. Particularly significant is the increase over the past two decades of air-sea N2O fluxes at a rate of 2.9 µmol m−2 d−1 per decade. These observations suggest that changes in the EBUS, such as intensification of upwelling and the prevalence of hypoxic waters may have implications for N2O emissions and fixed nitrogen loss, potentially influencing coastal productivity and climate. © The Author(s) 2024. |
| Multisequal aeolian deposition during the Holocene in southwestern Patagonia (51°S) was modulated by southern westerly wind intensity and vegetation type | Quaternary Science Reviews | Flores-Aqueveque, V.; Villaseñor, T.; Gómez-Fontealba, C.; Alloway, B.; Alfaro, S.; Pizarro, H.; Guerra, L.; Moreno, P. | 2024 | Agua y Extremos | 10.1016/j.quascirev.2024.108616 | https://doi.org/10.1016/j.quascirev.2024.108616 | art108616 | Vol: 331.0 | 02773791 | Thomson Reuters ISI (SCIE) | English | We studied a multisequal soil succession (MSS) just south of Torres del Paine National Park (51°S), at the present-day core of the Southern Westerly Winds (SWW). The Río Serrano Section comprises paleosol horizons with associated intervening loess and sandy loess beds formed during the Holocene. Our record suggests strong and stable aeolian activity between ∼9.3–7.2 ka followed by a decline with centennial-scale variations until ∼5 ka. A strengthening commenced at ∼5 ka and culminated in a maximum between ∼2.2–0.5 ka with millennial-scale variations. Subsequent weakening of aeolian activity between ∼0.5 and 0 ka was coeval with the deposition of a ∼40 cm-thick paleosol, after which aeolian activity increased abruptly and reached an unprecedented maximum starting in the mid-20th century. The inferred wind intensity variations from our data bear partial agreement with competing hypotheses of SWW evolution, which postulate minimum SWW influence in SW Patagonia during the early Holocene and maximum influence during the Late Holocene, or vice versa. When analyzed through the lens of vegetation physiognomy/distribution and associated hydrological balance inferences from neighboring sites, our results suggest a primary control by precipitation and wind speeds associated to SWW strength at regional scale, modulated by the position of the forest/steppe ecotone east of the austral Andes. Human activities during the mid-20th century (deforestation, fire-regime shifts, livestock grazing, land use changes) caused an unprecedented increase in aeolian activity through decreased vegetation cover that increased sediment availability for aeolian transport, marking a striking difference with the magnitude of natural processes before the Anthropocene. Our results highlight the importance of climate change and natural/human-driven changes in vegetation cover for deciphering wind intensity histories, particularly in the transition from humid to semiarid environments along the eastern slope of the southern Patagonian Andes. © 2024 Elsevier Ltd | |
| Atmospheric River Rapids and Their Role in the Extreme Rainfall Event of April 2023 in the Middle East | Geophysical Research Letters | Francis, D.; Fonseca, R.; Bozkurt, D.; Nelli, N.; Guan, B. | 2024 | Zonas Costeras | 10.1029/2024GL109446 | https://doi.org/10.1029/2024GL109446 | arte2024GL109446 | Vol: 51.0 Issue: 12.0 | 00948276 | Thomson Reuters ISI (SCIE) | English | The mesoscale dynamics of a record-breaking Atmospheric River (AR) that impacted the Middle East in mid-April 2023 and caused property damage and loss of life are investigated using model, reanalysis and observational data. The high-resolution (2.5 km) simulations revealed the presence of AR rapids, narrow and long convective structures embedded within the AR that generated heavy precipitation (>4 mm hr−1) as they moved at high speeds (>30 m s−1) from northeastern Africa into western Iran. Gravity waves triggered by the complex terrain in Saudi Arabia further intensified their effects. Given the rising frequency of ARs in this region, AR rapids may be even more impactful in a warming climate, and need to be accounted for in reanalysis and numerical models. © 2024. The Author(s). | |
| Reconstruction of glaciers in the western boundary of the Altiplano (18.5°-19°S): Singularities and insights on potential drivers of past advances | Quaternary Science Advances | Gallardo, M.; Otto, J.; Gayo, E.; Sitzia, L. | 2024 | Ciudades Resilientes | 10.1016/j.qsa.2023.100158 | https://doi.org/10.1016/j.qsa.2023.100158 | art100158 | Vol: 13 | 26660334 | Thomson Reuters ISI (ESCI) | English | Today, glaciers in the western Altiplano are very scarce, even on peaks exceeding 6000 m. In this mostly ice-free landscape, however, moraines and other glacial deposits are commonly found attesting to quite different climate conditions that favored the advance of glaciers in the past. Although other areas of the Altiplano have been commonly accounted for regarding paleoclimate reconstructions, western Altiplano has been often overlooked. Here we present a detailed map of glacial landforms and a paleoglacier reconstruction from a test area in the western Altiplano between 18.5° and 19°S. We reconstructed regional equilibrium line altitudes (ELA) for several moraine stages, representing extensive past glacier advances in the region. During a prominent and ubiquitous ‘Principal Moraine (PM)’ stage glaciers from most peaks and all orientations advanced to altitudes of up to 4000 m asl. Reconstructed PM ELAs along 90 valleys range from 4400 to 5000 m asl. ELA distribution reveals a strong aspect-dependency at the western boundary of the Altiplano, with ELAs 300 m lower on west-facing glaciers than east-facing glaciers. The coincidence of such steep gradient with a prominent NW-SE ridge accounts for topographic control on the precipitation and thus in the advance of glaciers along the western boundary of the Altiplano. To the east, ELAs from the peaks towering the Altiplano are comparable to ELAs from east-facing glaciers at the western Altiplano boundary but show little to no aspect-dependency. Since these patterns cannot be solely explained by increased moisture advection from the Amazon basin, we suspect that western-sourced moisture associated with increased frequency of cold fronts and cut-off events played an important role in the glacier dynamics at this latitude. Nevertheless, further investigations are required to evaluate the relative role of both precipitation regimes on the glacier dynamics from the westernmost Altiplano. © 2023 The Authors | |
| Opinion: Strengthening research in the Global South - atmospheric science opportunities in South America and Africa | Atmospheric Chemistry and Physics | Garland, R.; Altieri, K.; Dawidowski, L.; Gallardo, L.; Mbandi, A.; Rojas, N.; Touré, N. | 2024 | Ciudades Resilientes | 10.5194/acp-24-5757-2024 | https://doi.org/10.5194/acp-24-5757-2024 | 5757-5764 | Vol: 24.0 Issue: 10.0 | 16807316 | Thomson Reuters ISI (SCIE) | English | To tackle the current pressing atmospheric science issues, as well as those in the future, a robust scientific community is necessary in all regions across the globe. Unfortunately, this does not yet exist. There are many geographical areas that are still underrepresented in the atmospheric science community, many of which are in the Global South. There are also larger gaps in the understanding of atmospheric composition, processes, and impacts in these regions. In this opinion, we focus on two geographical areas in the Global South to discuss some common challenges and constraints, with a focus on our strengths in atmospheric science research. It is these strengths, we believe, that highlight the critical role of Global South researchers in the future of atmospheric science research. © 2024 Copernicus Publications. All rights reserved. | |
| Atmospheric Rivers in South-Central Chile: Zonal and Tilted Events | Atmosphere | Garreaud, R.; Jacques-Coper, M.; Marín, J.; Narváez, D. | 2024 | Agua y Extremos; Zonas Costeras | 10.3390/atmos15040406 | https://doi.org/10.3390/atmos15040406 | art406 | Vol: 15.0 Issue: 4.0 | 20734433 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The extratropical west coast of South America has one of the largest frequencies of landfalling atmospheric rivers (ARs), with dozens of events per season that account for ~50% of the annual precipitation and can produce extreme rainfall events in south-central Chile. Most ARs form an acute angle with the Andes, but, in some cases, the moist stream impinges nearly perpendicular to the mountains, referred to as zonal atmospheric rivers (ZARs). Enhanced surface-based and upper-air measurements in Concepcion (36.8° S), as well as numerical simulations, were used to characterize a ZAR and a meridionally oriented AR in July 2022. They represent extremes of the broad distribution of winter storms in this region and exhibit key features that were found in a composite analysis based on larger samples of ZARs and tilted ARs. The latter is associated with an upper-level trough, broad-scale ascent, extratropical cyclone, and cold front reaching southern Chile. Instead, ZARs are associated with tropospheric-deep, strong zonal flow and a stationary front across the South Pacific, with ascent restricted upstream of the Andes. Consequently, ZARs have minimum precipitation offshore but a marked orographic precipitation enhancement and exhibit relatively warm temperatures, thus resulting in an augmented risk of hydrometeorological extreme events. © 2024 by the authors. |
| Remote sensing biodiversity monitoring in Latin America: Emerging need for sustained local research and regional collaboration to achieve global goals | Global Ecology and Biogeography | Garzon-Lopez, C.; Miranda, A.; Moya, D.; Andreo, V. | 2024 | Cambio de Uso de Suelo | 10.1111/geb.13804 | https://doi.org/10.1111/geb.13804 | arte13804 | Vol: 33.0 Issue: 4.0 | 1466822X | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Aim: Biodiversity monitoring at global scales has been identified as one of the priorities to halt biodiversity loss. In this context, Latin America and the Caribbean (LAC), home to 60% of the global biodiversity, play an important role in the development of an integrative biodiversity monitoring platform. In this review, we explore to what extent LAC has advanced in the adoption of remote sensing for biodiversity monitoring and what are the gaps and opportunities to integrate local monitoring into global efforts to halt biodiversity loss. Location: Latin America and the Caribbean. Time period: 1995 to 2022. Taxa studied: Terrestrial organisms. Methods: We reviewed the application of remote sensing for biodiversity monitoring in LAC aiming to identify gaps and opportunities across countries, ecosystem types and research networks. Results: Our analysis illustrates how the use of remote sensing in LAC is disproportionately low in relation to the biodiversity it supports. Main conclusions: Build upon this analysis, we present, discuss and offer perspectives regarding four gaps identified in the application of remote sensing for biodiversity monitoring in Latin America and the Caribbean, namely (1) alignment between remote sensing data resolution and ecosystem structure; (2) investment in research, institutions and capacity building within researchers and stakeholders; (3) decolonized practices that promote access to publishing outlets and pluralistic participation among countries that facilitate exchange of experiences and capacity building; and (4) development of networks within and across regions to advance in ground surveys, ensure access and to foster the use of remote sensing data. © 2024 The Authors. Global Ecology and Biogeography published by John Wiley & Sons Ltd. |
| Screening CMIP6 models for Chile based on past performance and code genealogy | Climatic Change | Gateño, F.; Mendoza, P.; Vásquez, N.; Lagos-Zúñiga, M.; Jiménez, H.; Jerez, C.; Vargas, X.; Rubio-Álvarez, E.; Montserrat, S. | 2024 | Zonas Costeras | 10.1007/s10584-024-03742-1 | https://doi.org/10.1007/s10584-024-03742-1 | art87 | Vol: 177.0 Issue: 6.0 | 01650009 | Thomson Reuters ISI (SCIE) | English | We describe and demonstrate a two-step approach for screening global climate models (GCMs) and produce robust annual and seasonal climate projections for Chile. First, we assess climate model simulations through a Past Performance Index (PPI) inspired by the Kling-Gupta Efficiency, which accounts for climatological averages, interannual variability, seasonal cycles, monthly probabilistic distribution, spatial patterns of climatological means, and the capability of the GCMs to reproduce teleconnection responses to El Niño Southern Oscillation (ENSO) and the Southern Annular Mode (SAM). The PPI formulation is flexible enough to include additional variables and evaluation metrics and weight them differently. Secondly, we use a recently proposed GCM classification based on model code genealogy to obtain a subset of independent model structures from the top 60% GCMs in terms of PPI values. We use this approach to evaluate 27 models from the sixth phase of the Coupled Model Intercomparison Project (CMIP6) and generate projections in five regions with very different climates across continental Chile. The results show that the GCM evaluation framework is able to identify pools of poor-performing and well-behaved models at each macrozone. Because of its flexibility, the model features that may be improved through bias correction can be excluded from the model evaluation process to avoid culling GCMs that can replicate other climate features and observed teleconnections. More generally, the results presented here can be used as a reference for regional studies and GCM selection for dynamical downscaling, while highlighting the difficulty in constraining precipitation and temperature projections. © The Author(s), under exclusive licence to Springer Nature B.V. 2024. | |
| Towards understanding human-environment feedback loops: the Atacama Desert case | Philosophical transactions of the Royal Society of London. Series B, Biological sciences | Gayo, E.; Lima, M.; Gurruchaga, A.; Estay, S.; Santoro, C.; Latorre, C.; McRostie, V. | 2024 | Ciudades Resilientes | 10.1098/rstb.2022.0253 | https://doi.org/10.1098/rstb.2022.0253 | 20220253 | Vol: 379 Issue: 1893 | 14712970 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The overall trajectory for the human-environment interaction has been punctuated by demographic boom-and-bust cycles, phases of growth/overshooting as well as of expansion/contraction in productivity. Although this pattern has been explained in terms of an interplay between population growth, social upscaling, ecosystem engineering and climate variability, the evoked demographic-resource-complexity mechanisms have not been empirically tested. By integrating proxy data for population sizes, palaeoclimate and internal societal factors into empirical modelling approaches from the population dynamic theory, we evaluated how endogenous (population sizes, warfare and social upscaling) and exogenous (climate) variables module the dynamic in past agrarian societies. We focused on the inland Atacama Desert, where populations developed agriculture activities by engineering arid and semi-arid landscapes during the last 2000 years. Our modelling approach indicates that these populations experienced a boom-and-bust dynamic over the last millennia, which was coupled to structure feedback between population sizes, hydroclimate, social upscaling, warfare and ecosystem engineering. Thus, the human-environment loop appears closely linked with cooperation, competition, limiting resources and the ability of problem-solving. This article is part of the theme issue 'Evolution and sustainability: gathering the strands for an Anthropocene synthesis'. |
| A monthly gridded burned area database of national wildland fire data | Scientific Data | Gincheva, A.; Pausas, J.; Edwards, A.; Provenzale, A.; Cerdà, A.; Hanes, C.; Royé, D.; Chuvieco, E.; Mouillot, F.; Vissio, G.; Rodrigo, J.; Bedía, J.; Abatzoglou, J.; Senciales González, J.; Short, K.; Baudena, M.; Llasat, M.; Magnani, M.; Boer, M.; González, M.; Torres-Vázquez, M.; Fiorucci, P.; Ja... | 2024 | Cambio de Uso de Suelo | 10.1038/s41597-024-03141-2 | https://doi.org/10.1038/s41597-024-03141-2 | art352 | Vol: 11.0 Issue: 1.0 | 20524463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | We assembled the first gridded burned area (BA) database of national wildfire data (ONFIRE), a comprehensive and integrated resource for researchers, non-government organisations, and government agencies analysing wildfires in various regions of the Earth. We extracted and harmonised records from different regions and sources using open and reproducible methods, providing data in a common framework for the whole period available (starting from 1950 in Australia, 1959 in Canada, 1985 in Chile, 1980 in Europe, and 1984 in the United States) up to 2021 on a common 1° × 1° grid. The data originate from national agencies (often, ground mapping), thus representing the best local expert knowledge. Key opportunities and limits in using this dataset are discussed as well as possible future expansions of this open-source approach that should be explored. This dataset complements existing gridded BA data based on remote sensing and offers a valuable opportunity to better understand and assess fire regime changes, and their drivers, in these regions. The ONFIRE database can be freely accessed at https://zenodo.org/record/8289245. © The Author(s) 2024. |
| Population dynamics and cultural niche construction during the Late Holocene in a mediterranean ecosystem (central Chile, 32°S−36°S) | Holocene | Godoy-Aguirre, C.; Frugone-Álvarez, M.; Gayo, E.; Campbell, R.; Lima, M.; Maldonado, A.; Latorre, C. | 2024 | Ciudades Resilientes | 10.1177/09596836231225722 | https://doi.org/10.1177/09596836231225722 | 509-518 | Vol: 34.0 Issue: 5.0 | 09596836 | Thomson Reuters ISI (SCIE) | English | Understanding socio-ecological systems over the long term can shed light on past adaptive strategies in environmentally sensitive regions. Central Chile is an emblematic case study for mediterranean ecosystems, where a progressive and sustained population increase began approximately 2000 years ago alongside significant landscape changes. In this work we analyzed regional paleo-demographic trends by compiling a new database of archaeological dates over the last 3000 years, and integrating population dynamics theory with an analysis of the spatio-temporal variation of regional cultural stages. Results show three moments of marked acceleration in population growth: just before agricultural adoption, during the Archaic Period (c. 700-300 BCE); during the second half of the ECP (500–900 CE); and during the Late Intermediate Period (1200–1400 CE). We also identified periods of deceleration in per capita growth rates, although population size continued to increase (300 BCE−500 CE, 900–1200 CE and after 1400 CE). These large shifts in the per capita growth rates coincide with major cultural changes associated with social and economic aspects. The pulses of major occupation show in general terms a more intensive use of the valleys as the population size increased, although the remaining ecosystems never ceased to be occupied with different economic and symbolic emphases. © The Author(s) 2024. | |
| Chile’s Valparaíso hills on fire | Science | González, M.; Syphard, A.; Fischer, A.; Muñoz, A.; Miranda, A. | 2024 | Agua y Extremos; Cambio de Uso de Suelo | 10.1126/science.ado5411 | https://doi.org/10.1126/science.ado5411 | 1424 | Vol: 383.0 Issue: 6690.0 | 00368075 | Thomson Reuters ISI (SCIE) | English | [No abstract available] | |
| Recent multispecies tree-growth decline reveals a severe aridity change in Mediterranean Chile | Environmental Research Letters | González-Reyes, Á.; Christie, D.; Schneider-Valenzuela, I.; Venegas-González, A.; Muñoz, A.; Hadad, M.; Gipoulou-Zuñiga, T.; Tapia-Marzan, V.; Gibson-Carpintero, S.; Santini-Junior, L.; LeQuesne, C.; Villalba, R. | 2024 | Agua y Extremos | 10.1088/1748-9326/ad4049 | https://doi.org/10.1088/1748-9326/ad4049 | art064046 | Vol: 19.0 Issue: 6.0 | 17489326 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Soil moisture (SM) is a crucial factor in the water cycle, sustaining ecosystems and influencing local climate patterns by regulating the energy balance between the soil and atmosphere. Due to the absence of long-term, in-situ measurements of SM, studies utilizing satellite-based data and tree-ring analysis have become valuable in assessing variations of SM at regional and multi-century scales, as well as determining its effects on tree growth. This information is particularly pertinent in biodiversity hotspots made up of semi-arid ecosystems currently threatened by climate change. In the Mediterranean Chile region (MC; 30°-37° S), an ongoing megadrought since 2010 has resulted in a significant decline in the forest throughout the area. However, the impact of SM on tree growth at a multi-species and regional level remains unexplored. We analyzed a new network of 22 tree-ring width chronologies across the MC to evaluate the main spatiotemporal tree-growth patterns of nine woody species and their correlation with SM, using PCA. We also reconstructed the SM variations over the past four centuries and assessed its connection with large-scale climate forcings. Our results indicate that the primary growth patterns (PC1) explained 27% of the total variance and displayed a significant relationship with SM between 1982-2015 (r = 0.91), accurately reflecting the current megadrought. The tree-ring SM reconstruction covers the period 1616-2018 and shows a strong decrease around the year 2007, revealing an unprecedented recent change in aridity with respect to the last four centuries. The intensity of the South Pacific subtropical anticyclone, which primarily owe their existence to the subsiding branch of the Hadley Cell, appears as the primary climatic mechanism correlated with the reconstruction and the present aridity conditions in MC. The current SM conditions align with anticipated aridity changes in MC, providing a bleak perspective of future regional climate. © 2024 The Author(s). Published by IOP Publishing Ltd. |
| Unraveling the chemistry of plant flammability: Exploring the role of volatile secondary metabolites beyond terpenes | Forest Ecology and Management | Guerrero, F.; Espinoza, L.; Carmona, C.; Blackhall, M.; Quintero, C.; Ocampo-Zuleta, K.; Paula, S.; Madrigal, J.; Guijarro, M.; Carrasco, Y.; Bustamante-Sánchez, M.; Miranda, A.; Yáñez, K.; Bergmann, J.; Taborga, L.; Toledo, M. | 2024 | Cambio de Uso de Suelo | 10.1016/j.foreco.2024.122269 | https://doi.org/10.1016/j.foreco.2024.122269 | art122269 | Vol: 572.0 | 03781127 | Thomson Reuters ISI (SCIE) | English | Plant flammability research has proven pivotal in comprehending the contribution of vegetation to the flammability of forest ecosystems. Yet, the relationship between many leaf chemical traits and plant flammability is poorly understood. While terpenes and some leaf nutrients in plants have been extensively studied for their role in flammability, a wide array of other secondary metabolites remain unexplored in this context. Here, we present the volatile secondary metabolites composition of fresh leaves from nine dominant species from central Chile, both native and exotic, and determine whether there is variability within and among species in chemical composition and flammability. Moreover, we investigate how these compounds influence various leaf flammability traits. The Chilean Mediterranean ecosystem emerges as a useful study site given its unique endemic flora, increased frequency of forest fires, proliferation of invasive plants and extensive land conversion that favors the spread of fire-prone exotic species, and significant scarcity of phytochemical research dedicated to this ecosystem. A total of 118 volatile chemical compounds were quantified, belonging to over ten groups of volatile secondary metabolites. Terpenes, ketones, and hydrocarbons comprised 75 % of these compounds, and each species displayed a unique phytochemical profile. Surprisingly, some native species (Citronella mucronata, Cryptocarya alba) exhibited equivalent or higher leaf flammability than the well-known flammable exotics Eucalyptus globulus and Pinus radiata, respectively. Leaf flammability was best explained by the concentration of aldehydes, ketones, green leaf volatiles, and aromatic compounds. Interestingly, terpenes as well as moisture content were not significantly correlated with flammability. In conclusion, our results highlight the importance of considering a broader range of phytochemicals, beyond terpenes, to fully understand leaf flammability among species. Consequently, a deeper understanding -within and across ecosystems- of the influence exerted by diverse groups of phytochemicals on flammability is an urgent need for forest management planning in an increasingly flammable world. © 2024 Elsevier B.V. | |
| Growth decline and wood anatomical traits in Nothofagus dombeyi populations along a latitudinal gradient in the Andes, Chile | Trees - Structure and Function | Guzmán-Marín, R.; He, M.; Rossi, S.; Rodríguez, C.; Urrutia-Jalabert, R.; Lara, A. | 2024 | Cambio de Uso de Suelo | 10.1007/s00468-024-02564-z | https://doi.org/10.1007/s00468-024-02564-z | 09311890 | Thomson Reuters ISI (SCIE) | English | There is evidence of recent declines in tree growth in the temperate forests of South America, due to the ongoing climate change. This study assessed growth-climate relationships and the xylem hydraulic architecture of coihue (Nothofagus dombeyi (Mirb.) Oerst) trees exposed to the warmer and drier conditions of recent decades. We selected four coihue populations along a latitudinal gradient in the Andes, Chile, corresponding to a wide range of variation in growing season precipitation (northern dry to southern wet sites). Tree-ring width was measured in 24–32 adult trees per site during the last 60 years. We measured wood anatomical traits in a subsample of four trees per site during the last 25 years. All data were correlated with climatic variables. During the studied period, SPEI-6 passed from positive to negative in all sites. Basal area increment decreased by 1.7 mm2 year−1 over the period 1960–2020. Tree-ring width had a positive correlation with precipitation at the drier sites and a negative correlation with maximum temperature at the wetter populations. We estimated a density of 1.78 × 10–4 and 1.2 × 10–4 vessels µm−2 in the xylem of dry and wetter sites, respectively. Vessel density had a negative correlation with precipitation at the driest site and a positive correlation with maximum temperature at wetter sites. The hydraulic diameter was smaller under drier conditions, reaching 68–75 µm in the driest and wettest sites, respectively. Among the traits measured, vessel density was the most sensitive to climate. Drier and warmer conditions were associated with an increased number of smaller sized vessels, especially at the northern populations. Compared with the southern populations of our gradient, the northern populations growing at the drier sites are more sensitive to the ongoing changes in climate, and potentially more vulnerable to the even drier conditions projected for the future. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024. | |||
| Out of sight, not out of mind: The effect of access to conservation sites on the willingness to pay for protecting endangered species | Ecological Economics | Henríquez, M.; Vásquez-Lavín, F.; Barrientos, M.; Ponce Oliva, R.; Lara, A.; Flores-Benner, G.; Riquelme, C. | 2024 | Cambio de Uso de Suelo | 10.1016/j.ecolecon.2024.108280 | https://doi.org/10.1016/j.ecolecon.2024.108280 | art108280 | Vol: 224.0 | 09218009 | Thomson Reuters ISI (SCIE; SSCI) | English | According to the latest global assessment report on biodiversity and ecosystem services, nature and biodiversity have experienced a global decline, making the development of conservation policies urgent. Herein, we used a contingent valuation survey to estimate the economic value of a reintroduction program for the huemul (Hippocamelus bisulcus), an endangered charismatic species in Chile. Our novel approach exploits changes in the access to the site to disentangle nonuse value from use value. We use parametric and nonparametric models to estimate the willingness to pay for the program. Our findings consistently indicate that the conservation of the huemul is valued more when tourist access is restricted, as opposed to allowing visitors access to reintroduction areas. We also analyze the sensitivity of this main finding to different cut-off points of a certainty scale, showing that the results are robust. We hypothesize that people are willing to pay a “premium” to keep the conservation site “out of sight” from tourist activities. This could also be related to the belief that a reintroduction program would be more effective if access was not allowed. A cost-benefit analysis using the most conservative assumptions suggests that social benefit significantly outperforms cost. © 2024 Elsevier B.V. | |
| Nudges versus prices: Lessons and challenges from a water-savings program | Energy Economics | Hernández, F.; Jaime, M.; Vásquez, F. | 2024 | Cambio de Uso de Suelo | 10.1016/j.eneco.2024.107546 | https://doi.org/10.1016/j.eneco.2024.107546 | art107546 | Vol: 134.0 | 01409883 | Thomson Reuters ISI (SSCI) | English | This study evaluates the effects of two exogenous interventions targeting residential consumers using both pecuniary and nonpecuniary incentives, with the potential of increasing the moral and monetary costs of water use. The first intervention provided households with personalized reports including normative information regarding household water use compared with neighbors. The second intervention consisted of an exogenous change in water tariffs. The timing of the interventions provides a unique opportunity to separately assess both the individual and combined effects of each policy instrument. The empirical analysis was conducted on the same sample households assessed in the field experiment by Jaime and Carlsson (2018), whose behavior was followed one year after implementation. The results reveal that both nonpecuniary and pecuniary incentives significantly reduce water use when each instrument is applied separately, with the change in tariffs generating larger reductions in water use, compared with information provision, at 11% vs. 7%, respectively. However, the effectiveness of the combined policy depends on the setting of implementation. While the differentiated effects of the social information campaign associated with the change in tariffs suggest this policy remains effective, the evidence also suggests potential crowding-out effects arising upon the introduction of the new tariff regime. The largest reductions in water use are achieved when the instruments are jointly implemented. Findings shed light on the importance of accurately defining the timing and order of the interventions to maximize their impact on resource conservation. © 2024 | |
| Land subdivision in the law's shadow: Unraveling the drivers and spatial patterns of land subdivision with geospatial analysis and machine learning techniques in complex landscapes | Landscape and Urban Planning | Herrera-Benavides, J.; Pfeiffer, M.; Galleguillos, M. | 2024 | Cambio de Uso de Suelo | 10.1016/j.landurbplan.2024.105106 | https://doi.org/10.1016/j.landurbplan.2024.105106 | art105106 | Vol: 249.0 | 01692046 | Thomson Reuters ISI (SCIE; SSCI) | English | Land subdivisions, especially in rural areas, pose a significant threat to sustainable development in many regions of the world. This issue is particularly challenging to understand in complex landscapes, where many biophysical and anthropic drivers interact without the necessary land regulatory guidance. We combined kernel density analysis and machine learning modeling to unravel the spatial patterns of land subdivisions and the complex relationships between their drivers. We used the Los Lagos region in southern Chile as a study case because it is a global biodiversity hotspot where land subdivisions are constantly increasing. We identify a significant increasing trend of subdivisions. Our modeling approach showed robust performance with an R2 of 0.727, RMSE of 5.109, and a bias of −0.009. The proximity to urban areas, to the coast, distance to electric mains, demographic structure, and proximity to protected areas were significant predictors of land subdivision. Fertile lands, particularly those near urban centers, have become prime targets for subdivisions, exacerbating the conflict between urban development and agricultural sustainability. We highlight the increasing number of subdivisions on threatened ecosystems and highly productive soils. We discuss the interrelationship between the drivers and conclude that subdivision is primarily associated with conventional urban sprawl, although other urbanization phenomena could also be observed in some areas. These findings provide challenges and opportunities for global spatial planning and harmony with biodiversity conservation. © 2024 Elsevier B.V. | |
| Modeling and scenario building for climate change adaptation planning: The case of large mining in Chile | Environmental Development | Jiliberto Herrera, R.; Ramos-Jiliberto, R.; Dintrans, E.; Caro, A.; Espinoza, L.; Billi, M.; Valenzuela, M. | 2024 | Ciudades Resilientes | 10.1016/j.envdev.2024.101089 | https://doi.org/10.1016/j.envdev.2024.101089 | 101089 | Vol: 52.0 | 22114645 | Thomson Reuters ISI (SCIE) | en | The mining sector in Chile is a strategic industrial sector for the country. Existing evidence shows that it faces several serious climate change threats; precipitation and flooding, droughts, heatwaves, among others. This scene put pressure on the government and the industry to develop efficient adaptation plans. To date, adaptation plans are designed under the rather linear paradigm of predict-then-act or the impact-lea approach as they are characterized in the IPCC Assessment Report 5 (AR5). Literature and the IPCC reports have identified the limits of those planning paradigms showing the relevance of adaptation barriers or enabling conditions, which should be considered as intrinsic part of the planning problem. In methodological terms, planning for climate change risks implies an enriched adaptation plan problem, previously characterized only by an operative climate risk management, that must be described at the beginning of the decision-making process. In this study, our objective is to contribute to the climate change adaptation planning of large-scale mining in Chile. The study is based on a climate change adaptation planning approach that overcomes the limitations of the current paradigm. In doing so, we start from the understanding that what emerges as an object of analysis from adding to the climate risks their enabling managing conditions is a social system. The social system whose function is that social climate risk management takes place. Therefore, we call it the Social Management System for Adaptation to Climate Change (SMSACC). As such the SMSACC should be the adaptation planning key object. In the first place we modeled that system applying a qualitative system methodology and then we developed it into a mathematical model based on graph theory, in particular the signed digraphs. This allows us to simulate two types of intervention on the enlarged object of analysis of the large mining adaptation plan. On the one hand, we carried out a future scenario analysis based on prospective tools which enables us to understand the system's answer to different future behavior of its environment, including climate change. On the other hand, we simulate different strategic interventions options on the system, which facilitates understanding the system's reaction under different public policy approaches. The modeling and simulation results provided an insightful understanding of the dilemma of social adaptation management of large mining in Chile, and as such they are useful input for the planning process. © 2024 Elsevier B.V. | |
| Orbital modulation of subtropical versus subantarctic moisture sources in the southeast Pacific mid-latitudes | Nature Communications | Kaiser, J.; Schefuß, E.; Collins, J.; Garreaud, R.; Stuut, J.; Ruggieri, N.; De Pol-Holz, R.; Lamy, F. | 2024 | Agua y Extremos | 10.1038/s41467-024-51985-4 | https://doi.org/10.1038/s41467-024-51985-4 | art7512 | Vol: 15.0 Issue: 1.0 | 20411723 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Reconstructing rainfall variability and moisture sources is a critical aspect to understand past and future hydroclimate dynamics. Here, we use changes in the deuterium content of land-plant leaf waxes from two marine sediment cores located off Chile to reconstruct changes in rainfall amount and variation in moisture sources over the last ~50 ka. The records indicate increased moisture in central Chile during precession maxima, but an obliquity modulation is evident in southern Chile. While the southern westerly winds are the dominant factor of precipitation in southern Chile by bringing moisture and perturbations from the extratropics, the subtropics represent an additional moisture source during precession maxima due to a stronger subtropical jet increasing moisture transport from the tropics to the mid-latitudes. These findings imply that a combination of orbital modulation of moisture sources and rainfall amount explains the last glacial moisture maximum and early Holocene moisture minimum in south-central Chile. © The Author(s) 2024. |
| Trends in seasonal precipitation extremes and associated temperatures along continental Chile | Climate Dynamics | Lagos-Zúñiga, M.; Mendoza, P.; Campos, D.; Rondanelli, R. | 2024 | Zonas Costeras | 10.1007/s00382-024-07127-z | https://link.springer.com/10.1007/s00382-024-07127-z | 4205-4222 | Vol: 62.0 | 0930-7575, 1432-0894 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | We characterize trends in maximum seasonal daily precipitation (seasonal Rx1day), minimum (Tn), and maximum (Tx) daily temperatures during days with precipitation over continental Chile for the period 1979–2017, using surface stations and the AgERA5 gridded product derived from the ERA5 reanalysis dataset. We also examine seasonal trends of Sea Surface Temperature (SST), Precipitable Water (PW), Convective Available Potential Energy (CAPE), Eddy Kinetic Energy (EKE), Atmospheric Rivers (ARs) frequency, and upper air observations to seek possible mechanisms that explain precipitation trends. Our results show an increase in seasonal Rx1day during fall in the south part of Northern Chile (15–30°S) and during fall and winter in Austral Chile (45–57°S), and mostly negative trends in Central Chile (30–36°S), where a few locations with positive trends along the coast during summer. Temperature trends presented cooling patterns north of 33°S in almost all the seasons (< -2 °C/dec), while warming trends prevail south of 38°S (> 1 °C/dec). The highest values in Tn trends are obtained on the western slopes of the Andes around 30°S. We also explore temperature scaling in surface stations, finding strong positive super Clausius Clapeyron with Tn, especially between fall and spring in the 33–40°S region. Sounding observations in five stations across Chile suggest warming trends at 23.5°, 33°S, and 53°S, with a stabilization effect by enhanced warming in the upper troposphere, while presenting cooling trends in Puerto Montt (41.5°S). Seasonal trends in PW reveal moistening along southern Peru and northern Chile during spring and summer. Positive trends in CAPE are observed over 35–40°S (austral summer and fall) and the north Altiplano (autumn). SST analyses reveal strong cooling around 30°S in winter, which may explain the negative trends in seasonal Rx1day in central Chile. A warming spot on the northern Peruvian coast during fall may be responsible for humidification in front of Northern Chile, particularly during summer and fall. Positive EKE trends are detected south of 40°S, being stronger and reaching almost all of the coast during spring. ARs frequency unveils negative trends up to -5 days/dec during summer and positive trends of 1 day/dec in 40°- 50°S coastal regions during spring. More generally, the results presented here shed light on the main large-scale processes driving recent trends in precipitation extremes across continental Chile. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024. |
| Why the timing of climate assessments matters | Nature | Lambert, F. | 2024 | Agua y Extremos | 10.1038/d41586-024-03156-0 | https://doi.org/10.1038/d41586-024-03156-0 | 9-9 | Vol: 634.0 Issue: 8032.0 | 00280836 | Thomson Reuters ISI (SCIE) | en | The Intergovernmental Panel on Climate Change and the Paris agreement must align their schedules — or progress will slip. © Springer Nature Limited 2024. | |
| Post-fire Pinus radiata invasion in a threatened biodiversity hotspot forest: A multi-scale remote sensing assessment | Forest Ecology and Management | Leal-Medina, C.; Lopatin, J.; Contreras, A.; González, M.; Galleguillos, M. | 2024 | Cambio de Uso de Suelo | 10.1016/j.foreco.2024.121861 | https://doi.org/10.1016/j.foreco.2024.121861 | art121861 | Vol: 561.0 | 03781127 | Thomson Reuters ISI (SCIE) | English | Biological invasions are one of the most relevant factors of biodiversity loss, especially after fire disturbances. Wildfires can accelerate invasions of fire-prone species, like Pinus radiata, and dramatically alter ecosystems. However, how to assess the main impacts of this invasion process on the composition, structure, and functionality of ecosystems, including the post-fire revegetation processes, has not been fully resolved. This study aimed to evaluate the impacts of P. radiata invasion on fire-damaged forest ecosystems using combined remote sensing and in situ data, focusing particularly on changes in biodiversity, ecosystem structure, and functionality. The recovery of forest leaf area index (LAI) and the fraction of photosynthetically active radiation (FPAR) were monitored using Sentinel-2 time series products. Then the pre- and post-fire native community composition and the relationships of invasion and biodiversity with biotic and abiotic components were characterized using structural equation modeling (SEM). The postfire P. radiata density was mapped to quantify invasion intensity in three burned native forest fragments using generalized additive modeling (GAM) regressions based on UAS multispectral data. Biophysical metrics indicate that all forest fragments impacted by high, medium-high, and medium-low severity fires achieved a partial recovery of their canopy. The SEM model showed that microtopographic features and vegetation height explain native species diversity under pre-fire conditions due to their close relationship with favorable microclimatic conditions for species establishment. Vegetation height determined the abundance of P. radiata in post-fire conditions, and it negatively impacted diversity by promoting the homogenization of vegetation cover and altering diversity patterns. The general composition and abundance metrics also showed a substantial modification associated with the heavy (significant) invasion of P. radiata species. Predictive mapping of P. radiata density showed high accuracies (R2 =0.73 and explained deviation of 80%). The maps depicted an intense concentration of the invasive tree with a mean density of 76,217 individuals per ha−1 and high invasion spots with more than 176,000 individuals per ha−1. The quantification of invasion and mapping is a fundamental input for prioritizing areas and resources for a large-scale restoration program, and is a priority to avoid the loss of these highly threatened forest ecosystems. © 2024 Elsevier B.V. | |
| Positive feedbacks in deep-time transitions of human populations | Philosophical transactions of the Royal Society of London. Series B, Biological sciences | Lima, M.; Gayo, E.; Estay, S.; Gurruchaga, A.; Robinson, E.; Freeman, J.; Latorre, C.; Bird, D. | 2024 | Ciudades Resilientes | 10.1098/rstb.2022.0256 | https://doi.org/10.1098/rstb.2022.0256 | 20220256 | Vol: 379 Issue: 1893 | 14712970 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Abrupt and rapid changes in human societies are among the most exciting population phenomena. Human populations tend to show rapid expansions from low to high population density along with increased social complexity in just a few generations. Such demographic transitions appear as a remarkable feature of Homo sapiens population dynamics, most likely fuelled by the ability to accumulate cultural/technological innovations that actively modify their environment. We are especially interested in establishing if the demographic transitions of pre-historic populations show the same dynamic signature of the Industrial Revolution transition (a positive relationship between population growth rates and size). Our results show that population growth patterns across different pre-historic societies were similar to those observed during the Industrial Revolution in developed western societies. These features, which appear to have been operating during most of our recent demographic history from hunter-gatherers to modern industrial societies, imply that the dynamics of cooperation underlay sudden population transitions in human societies. This article is part of the theme issue 'Evolution and sustainability: gathering the strands for an Anthropocene synthesis'. |
| Characterizing the Atmospheric Mn Cycle and Its Impact on Terrestrial Biogeochemistry | Global Biogeochemical Cycles | Lu, L.; Li, L.; Rathod, S.; Hess, P.; Martínez, C.; Fernandez, N.; Goodale, C.; Thies, J.; Wong, M.; Alaimo, M.; Artaxo, P.; Barraza, F.; Barreto, A.; Beddows, D.; Chellam, S.; Chen, Y.; Chuang, P.; Cohen, D.; Dongarrà, G.; Gaston, C.; Gómez, D.; Morera-Gómez, Y.; Hakola, H.; Hand, J.; Harrison, R.;... | 2024 | Agua y Extremos | 10.1029/2023GB007967 | https://doi.org/10.1029/2023GB007967 | arte2023GB007967 | Vol: 38.0 Issue: 4.0 | 08866236 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The role of manganese (Mn) in ecosystem carbon (C) biogeochemical cycling is gaining increasing attention. While soil Mn is mainly derived from bedrock, atmospheric deposition could be a major source of Mn to surface soils, with implications for soil C cycling. However, quantification of the atmospheric Mn cycle, which comprises emissions from natural (desert dust, sea salts, volcanoes, primary biogenic particles, and wildfires) and anthropogenic sources (e.g., industrialization and land-use change due to agriculture), transport, and deposition, remains uncertain. Here, we use compiled emission data sets for each identified source to model and quantify the atmospheric Mn cycle by combining an atmospheric model and in situ atmospheric concentration measurements. We estimated global emissions of atmospheric Mn in aerosols (<10 μm in aerodynamic diameter) to be 1,400 Gg Mn year−1. Approximately 31% of the emissions come from anthropogenic sources. Deposition of the anthropogenic Mn shortened Mn “pseudo” turnover times in 1-m-thick surface soils (ranging from 1,000 to over 10,000,000 years) by 1–2 orders of magnitude in industrialized regions. Such anthropogenic Mn inputs boosted the Mn-to-N ratio of the atmospheric deposition in non-desert dominated regions (between 5 × 10−5 and 0.02) across industrialized areas, but that was still lower than soil Mn-to-N ratio by 1–3 orders of magnitude. Correlation analysis revealed a negative relationship between Mn deposition and topsoil C density across temperate and (sub)tropical forests, consisting with atmospheric Mn deposition enhancing carbon respiration as seen in in situ biogeochemical studies. © 2024. The Authors. |
| Fire–climate–human dynamics over the last 1800 years in the mesic Araucaria-Nothofagus forests | Journal of Biogeography | Martel-Cea, A.; Abarzúa, A.; González, M.; Jarpa, L.; Hernández, M. | 2024 | Cambio de Uso de Suelo | 10.1111/jbi.14839 | https://doi.org/10.1111/jbi.14839 | 1490-1504 | Vol: 51.0 Issue: 8.0 | 03050270 | Thomson Reuters ISI (SCIE) | English | Aim: Few palaeoenvironmental studies have been performed in Araucaria-Nothofagus forests, which are highly vulnerable to ongoing threats from climate change and anthropogenic activities. The primary goal of this work is to reconstruct past environmental changes related to fire disturbances over the last 1800 years in Tolhuaca National Park (TNP), Chile. Location: TNP, Araucanian region (38.2°S; 71.8°W), Northwestern Patagonia, Chile. Taxa: Araucaria araucana (Araucariaceae), Nothofagus spp. (Nothofagaceae). Methods: We completed charcoal and pollen analyses to create two new palaeoecological records that span 1800 years. We compared the lake-based reconstruction with the available local tree-ring fire scar chronologies from the last 430 years. Using these data, we compute forest index changes, biomass burning trends and compare with estimates of archaeological radiocarbon density. We place our inferences with context of published regional palaeoclimatic proxies from the Patagonian-Andean region. Results: Our results showed that fire activity was higher than present between 200 and 1500 CE, with peaks around 200–400 CE and 1100–1500 CE. Periods with high fire activity are associated with reduced forest cover, as Araucaria declined when mixed-severity fire regime occurred for extended periods. Pollen assemblages suggested a shift from dry to wet climate conditions at 1500 CE, and from 1750 CE onward, the arrival of exotic species reflected the land-use changes related to forest clearance and transhumance practices. Main Conclusions: The palaeoenvironmental reconstructions showed changes in vegetation, fire and climate over the past 1800 years in TNP. Wildfires have been the main disturbance process modifying the vegetation structure in the Araucaria and Nothofagus forests. Since 1750 CE intensive post-Hispanic land-use changes (forest clearances by fire and logging) took place in the study area, reducing the native vegetation cover. Climate variability, modulated by SAM-like and ENSO-like conditions, influenced the fire activity (availability and flammability of fuels), concomitantly with high archaeological density. The recent (after 2000 CE) increase of catastrophic wildfires may negatively affect the conservation strategies of Araucaria-Nothofagus forests. © 2024 John Wiley & Sons Ltd. | |
| Extreme coastal El Niño events are tightly linked to the development of the Pacific Meridional Modes | npj Climate and Atmospheric Science | Martinez-Villalobos, C.; Dewitte, B.; Garreaud, R.; Loyola, L. | 2024 | Agua y Extremos | 10.1038/s41612-024-00675-5 | https://doi.org/10.1038/s41612-024-00675-5 | art123 | Vol: 7.0 Issue: 1.0 | 23973722 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Coastal El Niño events—marine heatwaves instances in the far eastern Tropical Pacific during otherwise basin-scale neutral or cold conditions—can have severe societal impacts for countries along the west coast of South America, as exemplified by the 2017 and 2023 Peru-Ecuador floods. Due to the brevity of the observational record, it is not well understood whether these events are driven by local or large-scale processes. Here, to overcome this limitation we use a data-driven modeling approach to address their return period and forcing mechanisms. It is shown that extreme coastal El Niño events are a local manifestation in the eastern tropical Pacific of the constructive interactions of the Pacific Meridional Modes (PMM). Specifically, the North PMM yields a dipole-like anomaly SST pattern along the equator that favors its development, while the positive phase of the South PMM reinforces it. A smaller group of more moderate coastal events are remotely driven by zonal wind anomalies in the western tropical Pacific without the PMMs’ influence. The role of PMMs in the development of extreme coastal El Niño suggests that they may be more predictable than previously thought. © The Author(s) 2024. |
| Climatological Aspects of Notable Tornado Events in Chile | Monthly Weather Review | Marín, J.; Gutiérrez, F.; Gensini, V.; Barrett, B.; Pozo, D.; Jacques-Coper, M.; Veloso-Aguila, D. | 2024 | Zonas Costeras | 10.1175/mwr-d-23-0249.1 | https://doi.org/10.1175/mwr-d-23-0249.1 | 1803-1819 | Vol: 152.0 Issue: 8.0 | 0027-0644 | Thomson Reuters ISI (SCIE) | English | Tornadoes in Chile seem to develop in what are called “high-shear, low-CAPE” (HSLC) environments. An analysis of convective parameters from the ERA5 reanalysis during 16 notable tornadoes in Chile showed that several increased markedly before the time of the reports. The significant tornado parameter (STP) was able to discriminate the timing and location of the tornadoes, even though it was not created with that goal. We established thresholds for the severe hazards in environments with reduced buoyancy (SHERBE) parameter (>1) and the STP (<-0.3) to further identify days favorable for tornado activity in Chile. The SHERBE and STP parameters were then used to conduct a climatological analysis from 1959 to 2021 of the seasonal, interannual, and latitudinal variations of the environments that might favor torna- does. Both parameters were found to have a strong annual cycle. The largest magnitudes of STP were found to be generally confined to south-central Chile, in agreement with the (sparse) tornado record. The probability of a day with both SHERBE and STP values beyond their thresholds was greatest between May and August, which aligns with the months with the most tornado reports. The number of days with both SHERBE and STP beyond their respective thresholds was found to fluctuate interannually. This result warrants further study given the known interannual variability of synoptic and mesoscale weather in Chile. The results of this study extend our understanding of tornado environments in Chile and provide insight into their spatiotemporal variability. | |
| A perspective on the next generation of Earth system model scenarios: Towards representative emission pathways (REPs) | Geoscientific Model Development | Meinshausen, M.; Schleussner, C.; Beyer, K.; Bodeker, G.; Boucher, O.; Canadell, J.; Daniel, J.; Diongue-Niang, A.; Driouech, F.; Fischer, E.; Forster, P.; Grose, M.; Hansen, G.; Hausfather, Z.; Ilyina, T.; Kikstra, J.; Kimutai, J.; King, A.; Lee, J.; Lennard, C.; Lissner, T.; Nauels, A.; Peters, G.... | 2024 | Gobernanza e Interfaz Ciencia y Política | 10.5194/gmd-17-4533-2024 | https://doi.org/10.5194/gmd-17-4533-2024 | 4533-4559 | Vol: 17.0 Issue: 11.0 | 1991959X | Thomson Reuters ISI (SCIE) | English | In every Intergovernmental Panel on Climate Change (IPCC) Assessment cycle, a multitude of scenarios are assessed, with different scope and emphasis throughout the various Working Group reports and special reports, as well as their respective chapters. Within the reports, the ambition is to integrate knowledge on possible climate futures across the Working Groups and scientific research domains based on a small set of "framing pathways"such as the so-called representative concentration pathways (RCPs) in the Fifth IPCC Assessment Report (AR5) and the shared socioeconomic pathway (SSP) scenarios in the Sixth Assessment Report (AR6). This perspective, initiated by discussions at the IPCC Bangkok workshop in April 2023 on the "Use of Scenarios in AR6 and Subsequent Assessments", is intended to serve as one of the community contributions to highlight the needs for the next generation of framing pathways that is being advanced under the Coupled Model Intercomparison Project (CMIP) umbrella, which will influence or even predicate the IPCC AR7 consideration of framing pathways. Here we suggest several policy research objectives that such a set of framing pathways should ideally fulfil, including mitigation needs for meeting the Paris Agreement objectives, the risks associated with carbon removal strategies, the consequences of delay in enacting that mitigation, guidance for adaptation needs, loss and damage, and for achieving mitigation in the wider context of societal development goals. Based on this context, we suggest that the next generation of climate scenarios for Earth system models should evolve towards representative emission pathways (REPs) and suggest key categories for such pathways. These framing pathways should address the most critical mitigation policy and adaptation plans that need to be implemented over the next 10 years. In our view, the most important categories are those relevant in the context of the Paris Agreement long-term goal, specifically an immediate action (low overshoot) 1.5ĝ€¯°C pathway and a delayed action (high overshoot) 1.5ĝ€¯°C pathway. Two other key categories are a pathway category approximately in line with current (as expressed by 2023) near- and long-term policy objectives, as well as a higher-emission category that is approximately in line with "current policies"(as expressed by 2023). We also argue for the scientific and policy relevance in exploring two "worlds that could have been". One of these categories has high-emission trajectories well above what is implied by current policies and the other has very-low-emission trajectories which assume that global mitigation action in line with limiting warming to 1.5ĝ€¯°C without overshoot had begun in 2015. Finally, we note that the timely provision of new scientific information on pathways is critical to inform the development and implementation of climate policy. Under the Paris Agreement, for the second global stocktake, which will occur in 2028, and to inform subsequent development of nationally determined contributions (NDCs) up to 2040, scientific inputs are required by 2027. These needs should be carefully considered in the development timeline of community modelling activities, including those under CMIP7. © Copyright: | |
| Comparing SPI and SPEI to detect different precipitation and temperature regimes in Chile throughout the last four decades | Atmospheric Research | Meseguer-Ruiz, O.; Serrano-Notivoli, R.; Aránguiz-Acuña, A.; Fuentealba, M.; Nuñez-Hidalgo, I.; Sarricolea, P.; Garreaud, R. | 2024 | Agua y Extremos; Ciudades Resilientes | 10.1016/j.atmosres.2023.107085 | https://doi.org/10.1016/j.atmosres.2023.107085 | art107085 | Vol: 297 | 01698095 | Thomson Reuters ISI (SCIE) | English | Droughts are one of the main environmental challenges facing the world this century. The latitudinal and orographic characteristics of continental Chile leads different areas within it to experience very different regimes of precipitation and temperature, resulting in a wide variation in the occurrence and severity of droughts. Using the CR2Met 5 × 5 km resolution gridded monthly dataset covering the years from 1979 to 2019, we calculated the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evaporation Index (SPEI) of March and September at 3-, 6-, 9-, 12- and 24-months to: 1) relate them with different climate modes, and 2) determine their temporal evolution. We found that the Pacific Decadal Oscillation shows low positive correlations with SPI but no significant correlations with SPEI. The Multivariate El Niño Southern Oscillation shows different correlations in northern Chile, as well as El Niño 1 + 2 and the Antarctic Oscillation, for both SPI and SPEI. Both SPI and SPEI show negative (drier) trends in the north and center of Chile, while positive (wetter) trends appear in the south. SPEI shows stronger and more significant negative trends, influenced by the overall warming of the country. Warming trends are lower on the coast, so SPI could be a good indicator for coastal areas, while SPEI could be a good indicator for inland areas. Climate modes are useful for monthly and annual predictions, and by being a good drought predictor, they can help inform key public policies. These results are expected to help Chilean decision makers dealing with the challenges facing water management in the immediate future. © 2023 Elsevier B.V. | |
| General dry trends according to the standardized precipitation evapotranspiration index in mainland Chile | Frontiers in Earth Science | Meseguer-Ruiz, O.; Serrano-Notivoli, R.; Núñez-Hidalgo, I.; Sarricolea, P. | 2024 | Ciudades Resilientes | 10.3389/feart.2024.1355443 | https://doi.org/10.3389/feart.2024.1355443 | art1355443 | Vol: 12.0 | 22966463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Droughts are one of the main challenges affecting humanity in a global change context. Due to its spatial configuration, Chile experiences droughts of different severities, from arid to humid climates, ranging from sea level to elevations above 6,000 m above sea level (a.s.l.), but it is still unknown how this phenomenon behaves in distribution, duration and intensity. The goal of this study is to identify how droughts have affected the different climate regions of the country between 1979 and 2019. The Standardized Precipitation Evapotranspiration Index (SPEI), calculated for March and September, at the end of the humid season in the north and center-south of the country, respectively, and calculated at 3-, 6-, 9-, 12- and 24-month, allowed to determine the trends of the drought severity in a 5 × 5 km grid between 1979 and 2019. We found that negative and significant trends, indicating dry conditions, appear mainly in the Andes above 2,000 m a.s.l., where the main water reservoirs are located, affecting all climate types, except Mediterranean ones between 33°S and 38°S. The SPEI indicates general trends towards drier conditions across various elevations and climate types, with more pronounced negative trends in the north and central regions and some positive trends in the south. These trends suggest a significant impact on water availability, and highlight the need for focused policy initiatives to combat drought effects and manage water resources effectively. These findings are of main interest to Chile, one of the world’s leading producers of lithium and copper, with both industries requiring substantial amounts of water for extraction and processing, demanding high water availability in a drier territory. Copyright © 2024 Meseguer-Ruiz, Serrano-Notivoli, Nuñez-Hidalgo and Sarricolea. |
| Coordinated Geostationary, Multispectral Satellite Observations Are Critical for Climate and Air Quality Progress | AGU Advances | Millet, D.; Palmer, P.; Levelt, P.; Gallardo, L.; Shikwambana, L. | 2024 | Ciudades Resilientes | 10.1029/2024av001322 | https://doi.org/10.1029/2024av001322 | arte2024AV001322 | Vol: 5.0 Issue: 5.0 | 2576604X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | en | Satellite observations are critical for air quality and climate monitoring, and for developing the process understanding needed for reliable planning and predictions. Our current space‐based observing system stands at a crossroads with the early missions approaching their end‐of‐life. We articulate the challenges and needs to sustain and develop these environmental records into the future, focusing specifically on observations of gas‐phase atmospheric composition. |
| The implementation of a new governance model for climate action. Two years after the enactment of the Framework Law on Climate Change in Chile; [La implementación de un nuevo modelo de gobernanza para la acción climática. A dos años de la dictación de la Ley Marco de Cambio Climático en Chile] | Revista de Derecho Ambiental(Chile) | Moraga Sariego, P. | 2024 | Gobernanza e Interfaz Ciencia y Política | 10.5354/0719-4633.2024.75083 | https://revistaderechoambiental.uchile.cl/index.php/RDA/article/view/75083/76687 | 1-24 | Issue: 21 | 07180101 | Not indexed | All Open Access; Gold Open Access | English | |
| Development of a temperate rainforest zonation on the Pacific slopes of the North Patagonian Andes since ∼18 ka | Quaternary Science Reviews | Moreno, P.; Alloway, B.; Valenzuela, M.; Villacís, L.; Villa-Martínez, R. | 2024 | Agua y Extremos | 10.1016/j.quascirev.2024.108630 | https://doi.org/10.1016/j.quascirev.2024.108630 | art108630 | Vol: 332.0 | 02773791 | Thomson Reuters ISI (SCIE) | English | Few studies along the western slopes of the Andes in Northwestern Patagonia (NWP: 40°-44°S) allow examining vegetation development through environmental gradients in latitude and elevation along a time continuum since the Last Glacial Termination (T1, ∼18-11 ka). This complete biostratigraphic context is necessary for assessing the sequence, timing, rates, and direction of compositional/structural changes of the former vegetation, and for deciphering their environmental drivers. Here we report palynological results from two NWP sites spaced ∼22 km apart on the western Andean slopes, Caleta Puelche roadside section located near sea level and Lago Reflejos at mid elevations (∼800 m a.s.l.) and assess their continuous records since local ice-free conditions against other NWP sites. We find that cold-tolerant early successional trees dominated the initial stages of vegetation development in the Seno Reloncaví lowlands (∼18-17 ka), followed by thermophilous shade-tolerant North Patagonian rainforest (NPRF) trees, which achieved their maxima between ∼17 and 15 ka at low-elevations. A spread of cold- and shade-tolerant hygrophilous NPRF conifers ensued (∼14.8-13 ka) reaching similar magnitude at low- and mid-elevations, interrupted by increases in trees favored by canopy fragmentation linked to fire and explosive volcanism (∼13-11 ka). Thermophilous, shade-intolerant, summer-drought tolerant Valdivian rainforest (VRF) trees increased and achieved maxima between ∼10 and 8 ka, most notably in the lowlands, coeval with peak abundance of the NPRF conifers Fitzroya/Pilgerodendron and Podocarpus nubigena in mid-elevation Lago Reflejos, contemporaneous with their virtual disappearance near sea level. Widespread increases in cold-tolerant hygrophilous NPRF trees occurred after ∼8 ka, followed by mixing of NPRF and VRF elements in the lowlands after ∼6.3 ka with centennial-scale alternations. Inter-site and regional coherences of our findings suggest that variations in Southern Westerly Wind influence, along with disturbance regimes of natural and human origin, have driven the composition, structure, dynamics, and zonation of temperate rainforests in NWP since T1. We observe that Lago Reflejos features the highest abundance of Fitzroya cupressoides at regional scale since ∼12 ka, attesting to the importance of mid-elevation Andean environments for the persistence of these highly valued trees in the context of postglacial climate evolution, shifts in fire regimes, volcanic, and human disturbance in NWP. © 2024 Elsevier Ltd | |
| Climatic and disturbance impacts on temperate rainforest development since ∼18 ka in central-west Isla Grande de Chiloé (42.7°S) | Quaternary Science Reviews | Moreno, P.; Gonzalorena, L.; Hernández, L. | 2024 | Agua y Extremos | 10.1016/j.quascirev.2024.108688 | https://doi.org/10.1016/j.quascirev.2024.108688 | art108688 | Vol: 333.0 | 02773791 | Thomson Reuters ISI (SCIE) | English | Understanding the role of disturbance regimes on terrestrial ecosystems is often compounded by the paucity of time series sufficiently long and detailed to capture triggering events and the sequence of changes in species composition, community structure and dynamics along a time continuum until the present. Adding complexity to this problem, disturbance regimes and the distribution/competitive interactions of participating species may vary in time with shifts in mean climatic conditions and variability. Here we present results from sediment cores we collected from small closed-basin lakes near the Pacific coast of central Isla Grande de Chiloé, a sector with the lowest seasonality and recurrence of explosive volcanic events in Northwestern Patagonia (NWP). Our aim is examining vegetation development since the last glaciation and exploring potential climatic and disturbance impacts. We found rapid establishment of closed-canopy rainforests, which have persisted with little variation in terms of physiognomy until the present. Significant changes in species composition, structure, dynamics, and rates of change are evident over the last ∼18,000 years, along with fire maxima at ∼16.7 ka, ∼12.7 ka, between ∼11.7-9 ka, from ∼2 ka to the present, and minima in the interim. Fires precede major increases in disturbance favored taxa, which correspond in timing with fire activity maxima at NWP scale. The most recent ∼2000 years coincide with the highest number and ubiquity of human occupations at central-west and NWP scale, raising the possibility that fires were driven by human activities near our study sites. We detect a conspicuous increase in disturbance-favored trees ∼150 years after deposition of the Puma Verde Tephra (∼8.3 ka) and interpret their subsequent maintenance by frequent blowdown events after ∼7.5 ka in exposed sectors of the Coastal Range. We posit that enhanced storminess driven by stronger Southern Westerly Winds since ∼7.5 ka has favored early successional opportunistic trees in detriment of old-growth forests dominated by shade-tolerant species, generating a spatial mosaic of forest patches or gaps in different stages of recovery. © 2024 | |
| Unraveling the Dynamics of Moisture Transport During Atmospheric Rivers Producing Rainfall in the Southern Andes | Geophysical Research Letters | Mudiar, D.; Rondanelli, R.; Valenzuela, R.; Garreaud, R. | 2024 | Agua y Extremos; Zonas Costeras | 10.1029/2024GL108664 | https://doi.org/10.1029/2024GL108664 | arte2024GL108664 | Vol: 51.0 Issue: 13.0 | 00948276 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Atmospheric rivers (ARs) are known to produce both beneficial and extreme rainfall, leading to natural hazards in Chile. Motivated to understand moisture transport during AR events, this study performs a moisture budget analysis along 50 zonally elongated ARs reaching the western coast of South America. We identify the convergence of moist air masses of tropical/subtropical origin along the AR as the primary source of vertically integrated water vapor (IWV). Over the open ocean, moisture convergence is nearly balanced by precipitation. The advection of moisture along the AR, although smaller compared to mass convergence, significantly increases toward the landfalling region. The near conservation of IWV over the open ocean, observed by tracking a Lagrangian atmospheric column along the ARs, is the explanation behind the seemingly tropical origin of ARs in time-lapse visualizations of IWV. © 2024. The Author(s). |
| Dataclima: Avanzando en la gestión de datos climáticos | Bits de Ciencias (DCC-UCH) | Muñoz, F.; Bastarrica, M. | 2024 | Gobernanza e Interfaz Ciencia y Política | https://www.dcc.uchile.cl/Bitsdeciencia26 | 64-68 | Issue: 26 | 0718-8005 | Not indexed | Creative Commons Atribución-NoComercial-Compartir Igual 3.0 | Spanish | ||
| Propuesta de un indicador para estudiar la seguridad hídrica en la interfaz doméstica-comunitaria de áreas rurales chilenas | EURE | Nicolas-Artero, C.; Blanco, G. | 2024 | Gobernanza e Interfaz Ciencia y Política | 10.7764/eure.50.151.05 | https://doi.org/10.7764/eure.50.151.05 | 1-25 | Vol: 50.0 Issue: 151.0 | 0250-7161 | Thomson Reuters ISI (SSCI) | Creative Commons Attribution 4.0 International | Spanish | El presente artículo propone un indicador compuesto que permite identificar niveles de seguridad hídrica en la interfaz doméstica-comunitaria. Para ello analiza los procesos hidrosociales que dan origen a situaciones de escasez hídrica vividas por la población rural abastecida mediante organizaciones comunitarias en Chile rural. El indicador se basa en el estudio de caso de diez organizaciones comunitarias seleccionadas para representar la heterogeneidad existente en el país, a cuyos dirigentes se les aplicó entrevistas semiestructuradas en las cuales se realizaron, además, observaciones de campo. Del estudio se desprenden dos principales hallazgos: 1) No existe una correlación entre el tamaño de las organizaciones y los niveles de seguridad hídrica observados; 2) Los casos con mayores dificultades para acceder a recursos en cantidad suficiente no son los que enfrentan una inseguridad hídrica mayor, puesto que las organizaciones compensan esta dificultad con otros componentes. |
| Propuesta de un indicador para estudiar la seguridad hídrica en la interfaz doméstica – comunitaria de áreas rurales chilenas | Nicolas-Artero, C.; Gustavo, B. | 2024 | Gobernanza e Interfaz Ciencia y Política | https://hal.science/hal-04288805 | El presente artículo propone un indicador compuesto que permite identificar niveles de seguridad hídrica en la interfaz doméstica-comunitaria. Para ello analiza los procesos hidrosociales que dan origen a situaciones de escasez hídrica vividas por la población rural abastecida mediante organizaciones comunitarias en Chile rural. El indicador se basa en el estudio de caso de diez organizaciones comunitarias seleccionadas para representar la heterogeneidad existente en el país, a cuyos dirigentes se les aplicó entrevistas semiestructuradas en las cuales se realizaron, además, observaciones de campo. Del estudio se desprenden dos principales hallazgos: 1) No existe una correlación entre el tamaño de las organizaciones y los niveles de seguridad hídrica observados; 2) Los casos con mayores dificultades para acceder a recursos en cantidad suficiente no son los que enfrentan una inseguridad hídrica mayor, puesto que las organizaciones compensan esta dificultad con otros componentes. | ||||||||
| Exploring the multifunctional landscapes model in areas dominated by non-native tree plantations | Trees, Forests and People | Ortiz, A.; Gayó, E.; Henríquez, N.; Henríquez, B.; Pauchard, A. | 2024 | Ciudades Resilientes; Zonas Costeras | 10.1016/j.tfp.2024.100617 | https://doi.org/10.1016/j.tfp.2024.100617 | art100617 | Vol: 17.0 | 26667193 | Thomson Reuters ISI (ESCI) | All Open Access; Hybrid Gold Open Access | English | Multifunctional landscapes offer an integrated approach to production, conservation, and human well-being. However, the challenges of implementing them in territories where plantations dominate are yet not well understood. This is the case in Chile, where plantations of non-native pines and eucalypts are extensively planted in its South-Central regions for timber and pulp. The resulting landscape homogenization, environmental degradation, and increased wildfire risk have caused and exacerbated conflicts, impacting biodiversity and the well-being of local communities and the Indigenous Mapuche Peoples. After the mega-wildfires in the region in 2023, science-policy discourse promoted the multifunctional landscapes model as a way to increase resilience. But what does this multifunctionality mean in challenging social-ecological contexts? Here, we aim to explore and deconstruct the multifunctional landscapes model in the context of the complex social-ecological systems of South-Central Chile. In this study, a review of the literature and semi-structured interviews with regional experts were used to better understand the challenges and opportunities presented by multifunctional landscapes. The results show a need to deepen the knowledge of how to move the model into practice, such as how to identify and decide compatible activities in the landscape. The thematic analysis of the interviews showed that restoration and water security are shared goals across the diverse actors in South-Central Chile. However, there were significant differences in knowledge, experiences and resources. While a number of landscape initiatives exist in the region, significant work is needed to build a common vision before the potential of multifunctional landscapes can be realized. © 2024 The Author(s) |
| Geomorphology of the Caracota Valley, Western Altiplano, Northern Chile | Journal of Maps | Otto, J.; Gallardo, M.; Sitzia, L.; Osorio, D.; Gayo, E. | 2024 | Ciudades Resilientes | 10.1080/17445647.2024.2399948 | https://www.tandfonline.com/doi/abs/10.1080/17445647.2024.2399948 | 2399948 | Vol: 20.0 Issue: 1.0 | 17445647 | Thomson Reuters ISI (SCIE; SSCI) | English | We present a detailed geomorphological characterisation of the Caracota Valley (18°49′S 69°11′W, 4200–4600 m) in the western Altiplano of Northern Chile. A complex pattern of Pleistocene and Early Holocene glacier activity is responsible for the today's landscape configuration. Wetlands and temporary lakes significantly characterise the Caracota Valley setting providing water sources and storage required for life in this semi-arid landscape. Non-glacial processes at low intensities through most of the Holocene evoked little changes to the glacial landscape configuration, even though alluvial, fluvial and aeolian processes locally caused some sediment redistribution. The geomorphological study is embedded into a geoarchaeological research project on early human occupation in the zone of the Salar de Surire, Northern Chile, at 18°50′S. The geomorphological map offers a base to frame future discussions on the links between cultural and geomorphological places formation, which is a necessary step to move beyond site scales and ethnographic assumptions in the region of interest. | |
| Are we on the same page? Understanding value similarity and its impact on public trust in institutions of the energy sector | Energy Research and Social Science | Palomo-Vélez, G.; Perlaviciute, G.; Contzen, N.; Steg, L. | 2024 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.erss.2024.103715 | https://doi.org/10.1016/j.erss.2024.103715 | art103715 | Vol: 117.0 | 22146296 | Thomson Reuters ISI (SSCI) | All Open Access; Hybrid Gold Open Access | English | Value similarity – the extent to which people think institutions managing risks hold different or similar values to themselves, affects trust in those institutions and as such, plays a critical role in the public acceptability of energy projects and policies. Yet, we do not know what constitutes value similarity. How do people judge the level of similarity between their own values and the values of an institution? What role do different values play in theses judgments? And to what extent can these perceived similarities actually increase trust in institutions? To explore this, we decomposed the construct of value similarity into one's personal values and the perceived values of an institution, and explored if their congruence led to higher ratings of perceived value similarity and trust in institutions. We studied these relationships for three institutions playing important roles in the energy sector in the Netherlands, in current and future energy systems. Overall, response surface analyses (RSA) showed that people see their own values and the values of an institution as more similar and trust the institution more when they both endorse biospheric values more strongly. Further, perceived value similarity and trust in institutions are higher when people perceive institutions to have stronger biospheric values than themselves and when they expect institutions to be less egoistic than themselves. We discuss these findings reflecting on what they suggest regarding the role of shared values in increasing trust in relevant institutions and acceptability of energy risks. © 2024 The Authors |
| Comparison of carbon and water fluxes and the drivers of ecosystem water use efficiency in a temperate rainforest and a peatland in southern South America | Biogeosciences | Perez-Quezada, J.; Trejo, D.; Lopatin, J.; Aguilera, D.; Osborne, B.; Galleguillos, M.; Zattera, L.; Celis-Diez, J.; Armesto, J. | 2024 | Cambio de Uso de Suelo | 10.5194/bg-21-1371-2024 | https://doi.org/10.5194/bg-21-1371-2024 | 1371-1389 | Vol: 21.0 Issue: 5.0 | 17264170 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The variability and drivers of carbon and water fluxes and their relationship to ecosystem water use efficiency (WUE) in natural ecosystems of southern South America are still poorly understood. For 8 years (2015-2022), we measured carbon dioxide net ecosystem exchange (NEE) and evapotranspiration (ET) using eddy covariance towers in a temperate rainforest and a peatland in southern Chile. NEE was partitioned into gross primary productivity (GPP) and ecosystem respiration (Reco), while ET was partitioned into evaporation (E) and transpiration (T) and used to estimate different expressions of ecosystem WUE. We then used the correlation between detrended time series and structural equation modelling to identify the main environmental drivers of WUE, GPP, ET, E and T. The results showed that the forest was a consistent carbon sink (-486g23gCg m-2g yr-1), while the peatland was, on average, a small source (33g21gCg m-2g yr-1). WUE is low in both ecosystems and likely explained by the high annual precipitation in this region (g 1/4g 2100g mm). Only expressions of WUE that included atmospheric water demand showed seasonal variation. Variations in WUE were related more to changes in ET than to changes in GPP, while T remained relatively stable, accounting for around 47g % of ET for most of the study period. For both ecosystems, E increased with higher global radiation and higher surface conductance and when the water table was closer to the surface. Higher values for E were also found with increased wind speeds in the forest and higher air temperatures in the peatland. The absence of a close relationship between ET and GPP is likely related to the dominance of plant species that either do not have stomata (i.e. mosses in the peatland or epiphytes in the forest) or have poor stomatal control (i.e. anisohydric tree species in the forest). The observed increase in potential ET in the last 2 decades and the projected drought in this region suggests that WUE could increase in these ecosystems, particularly in the forest, where stomatal control may be more significant. © 2024 Jorge F. Perez-Quezada et al. |
| Disponibilidad y seguridad hídrica en el desarrollo de enfermedades crónicas no transmisibles ¿Nuevos factores de riesgo? | Revista Médica de Chile | Petermann-Rocha, F.; Pizarro, A.; Nazar, G.; Zambrano-Bigiarini, M.; Plaza-Garrido, A.; Díaz-Toro, F.; Troncoso-Pantoja, C.; Celis, A.; Sugg, D.; Celis-Morales, C. | 2024 | Agua y Extremos | 10.4067/s0034-98872024000500643 | https://www.revistamedicadechile.cl/index.php/rmedica/article/view/10971 | Vol: 152.0 Issue: 5.0 | 0717-6163 | Thomson Reuters ISI (SCIE) | Derechos de autor 2024 Revista Médica de Chile | Spanish | Las enfermedades crónicas no transmisibles (ECNT) son enfermedades de larga duración caracterizadas por presentar una lenta progresión y afectar a todos los grupos de edad y regiones en el mundo. Aunque estas patologías suelen asociarse con la edad avanzada, los datos epidemiológicos indican que tanto niños como adultos y personas mayores son vulnerables a distintos factores de riesgo que favorecen su aparición y desarrollo. Además de los factores de riesgo clásicos (por ejemplo, consumo de alcohol, tabaco, dieta), se han identificado otros factores emergentes que podrían influir directa o indirectamente en el desarrollo de estas enfermedades. Un ejemplo de estos últimos es el rol que podría desempeñar la variabilidad climática, específicamente la disponibilidad de recursos hídricos, en la evolución de estas patologías. |
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| Emerging energy sources' social acceptability: Evidence from marine-based energy projects | Renewable and Sustainable Energy Reviews | Ponce Oliva, R.; Estay, M.; Barrientos, M.; Estevez, R.; Gelcich, S.; Vásquez-Lavín, F. | 2024 | Cambio de Uso de Suelo | 10.1016/j.rser.2024.114429 | https://doi.org/10.1016/j.rser.2024.114429 | art114429 | Vol: 198.0 | 13640321 | Thomson Reuters ISI (SCIE) | English | Any decrease in global warming and its effects can only occur with a substantial reduction in anthropogenic CO2 emissions. In this context, renewable energy sources, particularly emerging sources, may play a central role in accelerating the transition from fossil fuels to cleaner energy sources. Emerging energy sources are renewable and have the potential to reduce global warming emissions; however, they are in the early development stages. These technologies include enhanced geothermal processes, artificial photosynthesis, and marine energy. In this study, we assess the main attributes that determine the social acceptance of renewable marine energy projects, highlighting individual preferences and heterogeneity for these projects. The results show that energy generation, ecological impact, job creation, co-ownership, and distributional justice are statistically significant attributes that support projects. However, individual preferences are highly heterogeneous. The existence of distinct classes (two in this case) with different preferences for marine energy attributes indicates that the one-size-fits-all approach may be inappropriate. Instead, policymakers and energy producers should tailor their proposals to meet the needs of both groups, considering their preferences and concerns. © 2024 Elsevier Ltd | |
| La Ciencia y la Cooperación como Guardianas del Océano frente al Cambio Climático en las Américas | Revista Costarricense de Política Exterior San José, Costa Rica | Ramajo, L. | 2024 | Zonas Costeras | https://www.cr2.cl/revista-costarricense-de-politica-exterior-edicion-especial-diplomacia-azul-una-mirada-hacia-el-oceano/ | 19-29 | Vol: MMXXIV Issue: Edición especial: Diplomacia Azul: Una mirada hacia el Océano | 1659-0012 | cr2.cl | Spanish | The increase in greenhouse gases resulting from human activities affects all natural and human systems on the planet. Changes in climatic conditions, along with certain anthropogenic uses and activities, significantly impact the ocean and its ecosystems, putting water and food security, people’s well-being, marine biodiversity, productive activities such as fisheries, aquaculture, and tourism, as well as the economies of countries highly dependent on the ocean at risk. In Central and South America, one of the most vulnerable and exposed regions to climate change, rising ocean temperatures, ocean acidification, deoxygenation, and other threats, along with the overexploitation of resources and ecosystems such as mangroves or kelp forests, are already affecting the countries in the region in multiple ways. Addressing climate change requires high levels of information and scientific knowledge, as well as cooperation between countries and an interdisciplinary and transdisciplinary approach when tackling complex issues that arise. Since 1992, the region has had the presence of the Inter-American Institute for Global Change Research (IAI), a regional intergovernmental entity that supports international coordination in scientific research, capacity building, and the science-policy dialogue regarding the scope, causes, and consequences of global changes in the Americas. Regarding the Ocean, since 2023, the IAI has had a committee that aims to establish a research and training program on the nexus between oceans, islands, and coastal systems in alignment with the United Nations Decade of Ocean Science. The purpose of this committee is to contribute from science with transformative solutions for sustainable development, resulting in a clean, healthy, resilient, productive, predictable, safe, accessible, inspiring, and attractive ocean for the region.with the United Nations Decade of Ocean Science. The purpose of this committee is to contribute from science with transformative solutions for sustainable development, resulting in a clean, healthy, resilient, productive, predictable, safe, accessible, inspiring, and attractive ocean for the region. |
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| Pine afforestation of treeless Mediterranean heathlands reduces productivity of neighbouring cork oak woodlands | Forest Ecology and Management | Repeto-Deudero, I.; Gómez-González, S.; García-Cervigón, A.; Navarro, G.; Ojeda, F. | 2024 | Cambio de Uso de Suelo | 10.1016/j.foreco.2024.122155 | https://doi.org/10.1016/j.foreco.2024.122155 | art122155 | Vol: 569.0 | 03781127 | Thomson Reuters ISI (SCIE) | English | Afforestation programs as a strategy to address the climate crisis are on the rise worldwide. Although concerns exist about the effects of afforesting treeless habitats on their biodiversity and ecosystem services, potential impacts on areas beyond afforestation boundaries have been largely overlooked. Cork oak (Quercus suber) woodlands in southern Spain are regarded as a successful example of sustainability. However, the afforestation of their neighbouring treeless habitats may compromise their productivity through indirect effects that are not fully understood. Using a multi-method approach, we studied the effects of the afforestation of Mediterranean heathland (herriza) areas with pine tree species on the productivity of neighbouring cork oak woodlands downslope over a 37-year period. The differences in Normalized Difference Vegetation Index (NDVI) and Basal Area Increment (BAI) between cork oak woodlands below open herriza and below afforested herriza became apparent approximately ten years after pine afforestation. Specifically, NDVI was significantly reduced in cork oak stands below afforested herriza areas for the remaining years, while a substantial decrease in BAI of cork oak trees was also associated with afforested herriza areas upslope. Moreover, the NDVI and BAI trends of cork oak stands below afforested herriza reached the minimum levels of the time series following an extreme drought event. Our results reveal that the ecological impacts of afforestation of naturally treeless habitats can expand beyond the plantation area. We propose that the restoration of treeless habitats, such as the herriza, in areas where pine plantations are no longer productive, may enhance their ecological services, particularly in the context of climate change. Therefore, afforestation programs worldwide should carefully consider the trade-offs between carbon mitigation and other ecosystem services at the landscape scale. © 2024 The Authors | |
| A 300-year tree-ring δ18O-based precipitation reconstruction for the South American Altiplano highlights decadal hydroclimate teleconnections | Communications Earth and Environment | Rodriguez-Caton, M.; Morales, M.; Rao, M.; Nixon, T.; Vuille, M.; Rivera, J.; Oelkers, R.; Christie, D.; Varuolo-Clarke, A.; Ferrero, M.; Magney, T.; Daux, V.; Villalba, R.; Andreu-Hayles, L. | 2024 | Agua y Extremos | 10.1038/s43247-024-01385-9 | https://doi.org/10.1038/s43247-024-01385-9 | art269 | Vol: 5.0 Issue: 1.0 | 26624435 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Tropical South American climate is influenced by the South American Summer Monsoon and the El Niño Southern Oscillation. However, assessing natural hydroclimate variability in the region is hindered by the scarcity of long-term instrumental records. Here we present a tree-ring δ18O-based precipitation reconstruction for the South American Altiplano for 1700–2013 C.E., derived from Polylepis tarapacana tree rings. This record explains 56% of December–March instrumental precipitation variability in the Altiplano. The tree-ring δ18O chronology shows interannual (2–5 years) and decadal (~11 years) oscillations that are remarkably consistent with periodicities observed in Altiplano precipitation, central tropical Pacific sea surface temperatures, southern-tropical Andean ice core δ18O and tropical Pacific coral δ18O archives. These results demonstrate the value of annual-resolution tree-ring δ18O records to capture hydroclimate teleconnections and generate robust tropical climate reconstructions. This work contributes to a better understanding of global oxygen-isotope patterns, as well as atmospheric and oceanic processes across the tropics. © The Author(s) 2024. |
| Stepping-up climate action and climate justice: Chile’s path towards a new model of climate governance | Environmental Research Letters | Rojas, M.; Billi, M. | 2024 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1088/1748-9326/ace4de | https://doi.org/10.1088/1748-9326/ace4de | art011003 | Vol: 19.0 Issue: 1.0 | 17489326 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | |
| Challenging the policy space: The legitimation of alternatives in Chilean pension policy (1980–2019) | Latin American Policy | Rozas-Bugueño, J.; Maillet, A. | 2024 | Gobernanza e Interfaz Ciencia y Política | 10.1111/lamp.12343 | https://doi.org/10.1111/lamp.12343 | 235-254 | Vol: 15.0 Issue: 2.0 | 20417365 | Thomson Reuters ISI (ESCI) | All Open Access; Hybrid Gold Open Access | English | In October 2019, Chile experienced its most significant cycle of protests since the return to democracy in 1990; one of the primary demands of this cycle was the improvement of pensions. What effect did the October upheaval have on the Chilean pension policy debate? How have ideas about the Chilean pension plan changed from its creation in 1981−2019? What are the main drivers of these changes? In this study, we propose the concept of policy space, which we define as the realm of ideas wherein public policies are debated and whose boundaries are determined by the legitimacy of ideas from relevant actors. We use a process-tracing approach based on qualitative data triangulation from several techniques including in-depth interviews, press analysis, and secondary document review. The findings indicate that the shift in the ideas related to pension policy is explained by two drivers—long-term linkage among actors and short-term social mobilization against the private pension system, which accelerated rapidly with the October 2019 protests. © 2024 The Authors. Latin American Policy published by Wiley Periodicals LLC on behalf of Policy Studies Organisation. |
| Toward a South American High-Impact Weather Reports Database | Bulletin of the American Meteorological Society | Salio, P.; Bechis, H.; Ribeiro, B.; de Lima Nascimento, E.; Galligani, V.; Garcia, F.; Alvarenga, L.; de los Milagros Alvarezs Imaz, M.; Baissac, D.; Barle, M.; Bastías-Curivil, C.; Benedicto, M.; Cancelada, M.; da Costa, I.; D’Amen, D.; de Elia, R.; Diaz, D.; Páez, A.; González, S.; Goede, V.; Goñi... | 2024 | Agua y Extremos; Zonas Costeras | 10.1175/BAMS-D-23-0063.1 | https://doi.org/10.1175/BAMS-D-23-0063.1 | E1204-E1217 | Vol: 105.0 Issue: 7.0 | 00030007 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Despite southern South America being recognized as a hotspot for deep convective storms, little is known about the socioenvironmental impacts of high-impact weather (HIW) events. Although there have been past efforts to collect severe weather reports in the region, they have been highly fragmented among and within countries, sharing no common protocol, and limited to a particular phenomenon, a very specific region, or a short period of time. There is a pressing need for a more comprehensive understanding of the present risks linked to HIW events, specifically deep convective storms, on a global scale as well as their variability and potential future evolution in the context of climate change. A database of high-quality and systematic HIW reports and associated socioenvironmental impacts is essential to understand the regional atmospheric conditions leading to hazardous weather, to quantify its predictability, and to build robust early warning systems. To tackle this problem and following successful initiatives in other regions of the world, researchers, national weather service members, and weather enthusiasts from Argentina, Brazil, Chile, Paraguay, and Uruguay have embarked on a multinational collaboration to generate a standardized database of reports of HIW events principally associated with convective storms and their socioenvironmental impacts in South America. The goal of this paper is to describe this unprecedented initiative over the region, to summarize first results, and to discuss the potential applications of this collaboration. SIGNIFICANCE STATEMENT: The South American Meteorological Hazards and their Impacts Database represents a collaborative multinational initiative aimed at systematically gathering data on high-impact weather events. Cross-border information exchange and collaborative efforts between national weather services, the academic sector, users, and weather enthusiasts will improve multihazard-impact-based forecasts and risk management strategies in the region. © 2024 American Meteorological Society. |
| Climate change perceptions in Latin America: From regional consensus to sociodemographic differences | Population and Environment | Sapiains, R.; Azocar, G.; Palomo-Vélez, G.; Ugarte, A.; Aldunce, P. | 2024 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.1007/s11111-024-00464-5 | https://doi.org/10.1007/s11111-024-00464-5 | art23 | Vol: 46.0 Issue: 4.0 | 01990039 | Thomson Reuters ISI (SSCI) | English | Despite its low contribution to greenhouse gases emission, Latin America is one of the most vulnerable regions to climate change. Economic, social, and political factors make difficult the preparation for ongoing and future impacts. Few studies have explored how people in this region perceive and respond to climate change. In this scenario, we conducted an online survey to address the following research question: How sociodemographic factors are influencing perceptions and emotional responses associated with climate change in LA countries? The final sample consisted of 7232 people, with an error of 2.8% for the total population from 18 countries, representing 67% of the region’s internet-accessible population. Data analysis involved descriptive statistics, cross-tabulations, and mixed linear models. Results indicate a consensus on the fact that climate change is already happening, that is totally or partially caused by human activities, that will worsen poverty and inequalities but also that is an opportunity to build a fairer society. Sociodemographic differences were also found, showing the importance of sex, age and having or not having children in multiple variables. We hope this study will contribute to a better understanding of this complex social issue, informing policies to encourage a greater engagement with climate action. © The Author(s), under exclusive licence to Springer Nature B.V. 2024. | |
| Changes in South American surface ozone trends: exploring the influences of precursors and extreme events | Atmospheric Chemistry and Physics | Seguel, R.; Castillo, L.; Opazo, C.; Rojas, N.; Nogueira, T.; Cazorla, M.; Gavidia-Calderón, M.; Gallardo, L.; Garreaud, R.; Carrasco-Escaff, T.; Elshorbany, Y. | 2024 | Agua y Extremos; Ciudades Resilientes | 10.5194/acp-24-8225-2024 | https://doi.org/10.5194/acp-24-8225-2024 | 8225-8242 | Vol: 24.0 Issue: 14.0 | 16807316 | Thomson Reuters ISI (SCIE) | English | In this study, trends of 21st-century ground-level ozone and ozone precursors were examined across South America, a less-studied region where trend estimates have rarely been comprehensively addressed. Therefore, we provided an updated regional analysis based on validated surface observations. We tested the hypothesis that the recent increasing ozone trends, mostly in urban environments, resulted from intense wildfires driven by extreme meteorological events impacting cities where preexisting volatile organic compound (VOC)-limited regimes dominate. We applied the quantile regression method based on monthly anomalies to estimate trends, quantify their uncertainties and detect trend change points. Additionally, the maximum daily 8 h average (MDA8) and peak-season metrics were used to assess short- and long-term exposure levels, respectively, for the present day (2017–2021). Our results showed lower levels in tropical cities (Bogotá and Quito), varying between 39 and 43 nmol mol−1 for short-term exposure and between 26 and 27 nmol mol−1 for long-term exposure. In contrast, ozone mixing ratios were higher in extratropical cities (Santiago and São Paulo), with a short-term exposure level of 61 nmol mol−1 and long-term exposure levels varying between 40 and 41 nmol mol−1. Santiago (since 2017) and São Paulo (since 2008) exhibited positive trends of 0.6 and 0.3 nmol mol−1 yr−1, respectively, with very high certainty. We attributed these upward trends, or no evidence of variation, such as in Bogotá and Quito, to a well-established VOC-limited regime. However, we attributed the greater increase in the extreme percentile trends (≥ 90th) to heat waves and, in the case of southwestern South America, to wildfires associated with extreme meteorological events. © Author(s) 2024. | |
| Diversity and functionality of soil prokaryotic communities in antarctic volcanic soils: insights from penguin-influenced environments | Polar Biology | Segura, D.; Jordaan, K.; Díez, B.; Tamayo-Leiva, J.; Doetterl, S.; Wasner, D.; Cifuentes-Anticevic, J.; Casanova-Katny, A. | 2024 | Zonas Costeras | 10.1007/s00300-024-03273-6 | https://doi.org/10.1007/s00300-024-03273-6 | 07224060 | Thomson Reuters ISI (SCIE) | English | In the nutrient-limited Antarctic terrestrial habitat, penguins transfer a significant amount of nutrients from the marine to the terrestrial ecosystem through their depositions (i.e., guano). This guano influences soil physicochemical properties, leading to the formation of ornithogenic soil rich in nutrients and organic matter. We hypothesize that soil prokaryotic communities will be strongly influenced by the contribution of nitrogenous nutrients from penguin rookeries, maintaining the influence over long distances. The objective was to establish how the soil prokaryotic diversity and community structure change with distance from a penguin colony, which provides large amounts of guano and nitrogenous compounds, and to study the effects of these nutrients on the functional role of these communities. Methods include volcanic soil sampling along a 1200 m transect from the penguin active rookery and the characterization of soil nutrient content and soil prokaryotic communities using 16S rRNA high-throughput amplicon sequencing. In contrast to our hypothesis, the results showed that the impact of guano from the penguin colony was restricted to the first 300 m. Probably because the penguin rookery was sheltered, strong wind and wind direction did not affect the transport of nutrients from the penguin rookery. Areas close to the penguin rookery were dominated by Proteobacteria and Bacteroidetes, while areas situated further away were dominated by Acidobacteria, Actinobacteria, Chloroflexi, Gemmatimonadetes, Nitrospirae, and Planctomycetes. Beta diversity analysis among the soil prokaryotic communities revealed a high degree of community heterogeneity, strongly associated with N compound characteristics (NH4, NO3, and %N), C, and pH. Inferences from N metabolism genes suggest a high potential of the microbial community for dissimilatory nitrate reduction genes (DNRA) to ammonium, assimilatory nitrate reduction (ANR), and denitrification. Although it is assumed that the nitrogenous compounds of the penguin colonies reach long distances and affect the prokaryotic community, this effect can vary with wind directions or the morphology of the site, reducing the impact of the guano over long distances, as our results indicate. On the other hand, functional predictions give some clues about the main actors in nitrogen cycling, through processes like dissimilatory nitrate reduction, assimilatory nitrate reduction, and denitrification. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024. | |||
| Paleolimnology of Lago Pichilaguna over the past ∼12,600 years based on a fine-resolution diatom record, northwestern Patagonia (41°S) | Quaternary Science Reviews | Sepúlveda-Zúñiga, E.; Villacís, L.; Maidana, N.; Sagredo, E.; Moreno, P. | 2024 | Agua y Extremos | 10.1016/j.quascirev.2024.108835 | https://doi.org/10.1016/j.quascirev.2024.108835 | art108835 | Vol: 339.0 | 02773791 | Thomson Reuters ISI (SCIE) | English | The Pacific sector of Northwestern Patagonia (NWP, 40°-44°S) is key for examining the interaction between climate variability, explosive volcanism, and human influences on southern mid-latitude ecosystems. A limited number of studies in this region, however, have focused on aquatic ecosystem and hydrologic balance (HB) changes throughout the Holocene. Here we report a fossil diatom record from Lago Pichilaguna, a small closed-basin lake located in the lowlands of the Chilean Lake District, that reveals prominent changes in species composition and functional groups since ∼12.6 cal ka BP. We interpret positive HB between ∼12.6–11.4 cal ka BP and from ∼5.7 cal ka BP until recent that alternate with negative HB between ∼11.4–6.9 cal ka BP. We observe centennial-scale fluctuations since ∼5.7 cal ka BP that culminate with a negative HB phase over the past ∼270 years. Coherent responses in terrestrial and aquatic ecosystems recorded in the Lago Pichilaguna sediments underscore the influence of variations in the Southern Westerly Winds in NWP from multimillennial to centennial timescales since ∼12.6 cal ka BP. These inferences replicate the timing and direction of changes from previous studies at regional, pan-Patagonian, and zonal scales. The magnitude and rapidity of changes in diatom assemblages that started at ∼0.2 cal ka BP exceeds the ranges of local natural variability since ∼12.6 cal ka BP. This abrupt change is associated with a negative HB phase at centennial timescale, deposition of a tephra layer, and large-scale disturbance by Chilean/European settlers. © 2024 Elsevier Ltd | |
| Picoplanktonic methane production in eutrophic surface waters | Biogeosciences | Tenorio, S.; Farías, L. | 2024 | Zonas Costeras | 10.5194/bg-21-2029-2024 | https://doi.org/10.5194/bg-21-2029-2024 | 2029-2050 | Vol: 21.0 Issue: 8.0 | 17264170 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Over the past decade, extensive research has delved into the methane (CH4) paradox, which involves aerobic CH4 production. We present noteworthy observations of CH4 oversaturation within the surface layer of the central Chile upwelling zone (36°S, 73°W) over two consecutive seasonal cycles (2018-2021). Complementing these observations, CH4 cycling experiments were conducted, utilizing distinct plankton fractions (encompassing the natural planktonic community, fractions <150, <3 and <0.2μm), in different productivity periods of phytoplanktonic production and composition throughout the year. Our findings underscore the pivotal role of picoplankton (<3μm) in CH4 production on the ocean surface, contrasting with the limited contribution of larger microorganisms (<150μm). Notably, incubations with methylated substrates, such as methylphosphonic acid (MPn) and trimethylamine (TMA), induce heightened CH4 production within the picoplanktonic fraction. This phenomenon is consistently observed during both upwelling (austral spring-summer) and non-upwelling (winter) seasons, with significance in the latter period, when Synechococcus sp. exhibits notably high relative abundance. Long-term microcosm experiments highlight the crucial roles played by heterotrophic bacteria and cyanobacteria in methylotrophic methanogenesis. This process enhances CH4 production, facilitated by the recycling of dissolved organic carbon (DOC). Picoplankton emerges as a pivotal factor influencing the recycling of methylated substrates, and it is responsible for maintaining CH4 supersaturation. These findings provide valuable insights into the biogeochemical processes driving CH4 dynamics, particularly in highly productive upwelling areas. © Copyright: |
| Exotic tree plantations in the Chilean Coastal Range: balancing the effects of discrete disturbances, connectivity, and a persistent drought on catchment erosion | Earth Surface Dynamics | Tolorza, V.; Mohr, C.; Zambrano-Bigiarini, M.; Sotomayor, B.; Poblete-Caballero, D.; Carretier, S.; Galleguillos, M.; Seguel, O. | 2024 | Cambio de Uso de Suelo | 10.5194/esurf-12-841-2024 | https://doi.org/10.5194/esurf-12-841-2024 | 841-861 | Vol: 12.0 Issue: 4.0 | 2196-6311 | Thomson Reuters ISI (SCIE) | en | ||
| New insights on the interannual surface mass balance variability on the South Shetland Islands glaciers, northerly Antarctic Peninsula | Global and Planetary Change | Torres, C.; Bozkurt, D.; Carrasco-Escaff, T.; Bolibar, J.; Arigony-Neto, J. | 2024 | Agua y Extremos; Zonas Costeras | 10.1016/j.gloplacha.2024.104506 | https://doi.org/10.1016/j.gloplacha.2024.104506 | art104506 | Vol: 239.0 | 09218181 | Thomson Reuters ISI (SCIE) | English | Few studies have assessed a comprehensive understanding of how the seasonal and interannual variability and trends of the surface mass balance (SMB), including the influence of atmospheric river (ARs), are governed by the climate on the South Shetland Islands (SSI) glaciers located in the northerly Antarctic Peninsula (AP). To address this gap, we comprehensively analyzed the correlations and regressions between seasonal and annual SMB with regional to global climate indices and a state-of-the-art AR tracking database from 1980 to 2019. The daily and monthly SMB was obtained from two physical glaciological models, which was verified against 19 years of annual and seasonal glacier-wide SMB observations available in three glaciers (Johnsons, Hurd, and Bellingshausen), showing a good ability to capture interannual and seasonal variability. Results indicate a low dependence of the SMB on main atmospheric modes of variability (e.g., El Niño-Southern Oscillation and the Southern Annular Mode), and a moderate dependence on regional climate indices based on atmospheric pressure anomalies and sea surface temperature anomalies over the Drake Passage. Furthermore, our findings reveal that ARs have different effects on the SMB depending on the season. For example, winter ARs tend to boost accumulation due to increased snowfall, while summer ARs tend to intensify surface melting due to increased sensible heat flux. Our study highlights the Drake Passage as a key region that has the potential to influence the interannual and seasonal variability of the SMB and other climate variables, such as air temperature and snowfall over the SSI. We suggest that future work should consider this region to better understand the past, present and future climate changes on the SSI and surrounding areas. © 2024 | |
| Camelids in the hyperarid core of the Atacama desert 12,000–11,000 years ago? A stable isotope study and its consequences for early human settlement | Quaternary Science Reviews | Ugalde, P.; Gayo, E.; Labarca, R.; Santoro, C.; Quade, J. | 2024 | Ciudades Resilientes | 10.1016/j.quascirev.2024.108750 | https://doi.org/10.1016/j.quascirev.2024.108750 | art108750 | Vol: 335.0 | 02773791 | Thomson Reuters ISI (SCIE) | English | How did hunter-gatherers initially settle and move across extreme environments? We conducted a multi-disciplinary study to tackle this question, focusing on how Paleoindigenous populations inhabited the hyperarid core of the Atacama Desert. Particularly, we examined the stable isotopic values of ∼12,000–11,200-year-old camelid and rodent bones and hair samples retrieved from low-elevation archaeological sites (Pampa del Tamarugal basin - PdT, 800–1200 masl). By integrating novel and existing data into a regional stable isotope ecology, we offer a baseline for interpreting our results. δ13C and δ15N values on archaeological remains show animals with different geographical origins. A first group includes camelids and rodents with lower δ15N values and δ13C values indicating a dominantly C3 diet, corresponding to animals either local to the PdT or from the Andean Steppe, at least ∼80 km away and between 4000 and 4500 masl. Most of these remains, however, come from residential sites and belong to young camelids, indicating a local origin. A second group presents a higher δ15N signal and δ13C values indicative of a mixed C3–C4 based diet. These animals were not local but source to the Puna at least ∼60 km away between 3200 - 4000 masl. We hypothesize that the first would correspond to animals associated with hunter-gatherer bands settled around a wetland and grove environment in the PdT. The second group could correspond to remains brought by humans from the Puna to the PdT. Our results demonstrate that during the Late Pleistocene/Early Holocene the Atacama was very different than today, supporting life that included large and mid-size game. These results also show that the core of the Atacama attracted animals and people and counters the notion of this ecosystem as a barren passageway from the Andes to the coast. © 2024 Elsevier Ltd | |
| CoCO2-MOSAIC 1.0: a global mosaic of regional, gridded, fossil, and biofuel CO2 emission inventories | Earth System Science Data | Urraca, R.; Janssens-Maenhout, G.; Álamos, N.; Berna-Peña, L.; Crippa, M.; Darras, S.; Dellaert, S.; Denier van der Gon, H.; Dowell, M.; Gobron, N.; Granier, C.; Grassi, G.; Guevara, M.; Guizzardi, D.; Gurney, K.; Huneeus, N.; Keita, S.; Kuenen, J.; Lopez-Noreña, A.; Puliafito, E.; Roest, G.; Rossi,... | 2024 | Ciudades Resilientes | 10.5194/essd-16-501-2024 | https://doi.org/10.5194/essd-16-501-2024 | 501-523 | Vol: 16.0 Issue: 1.0 | 18663508 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | en | Gridded bottom-up inventories of CO2 emissions are needed in global CO2 inversion schemes as priors to initialize transport models and as a complement to top-down estimates to identify the anthropogenic sources. Global inversions require gridded datasets almost in near-real time that are spatially and methodologically consistent at a global scale. This may result in a loss of more detailed information that can be assessed by using regional inventories because they are built with a greater level of detail including country-specific information and finer resolution data. With this aim, a global mosaic of regional, gridded CO2 emission inventories, hereafter referred to as CoCO2-MOSAIC 1.0, has been built in the framework of the CoCO2 project. CoCO2-MOSAIC 1.0 provides gridded (0.1° ×0.1° ) monthly emissions fluxes of CO2 fossil fuel (CO2ff, long cycle) and CO2 biofuel (CO2bf, short cycle) for the years 2015-2018 disaggregated in seven sectors. The regional inventories integrated are CAMS-REG-GHG 5.1 (Europe), DACCIWA 2.0 (Africa), GEAA-AEI 3.0 (Argentina), INEMA 1.0 (Chile), REAS 3.2.1 (East, Southeast, and South Asia), and VULCAN 3.0 (USA). EDGAR 6.0, CAMS-GLOB-SHIP 3.1 and CAMS-GLOB-TEMPO 3.1 are used for gap-filling. CoCO2-MOSAIC 1.0 can be recommended as a global baseline emission inventory for 2015 which is regionally accepted as a reference, and as such we use the mosaic to inter-compare the most widely used global emission inventories: CAMS-GLOB-ANT 5.3, EDGAR 6.0, ODIAC v2020b, and CEDS v2020_04_24. CoCO2-MOSAIC 1.0 has the highest CO2ff (36.7Gt) and CO2bf (5.9Gt) emissions globally, particularly in the USA and Africa. Regional emissions generally have a higher seasonality representing better the local monthly profiles and are generally distributed over a higher number of pixels, due to the more detailed information available. All super-emitting pixels from regional inventories contain a power station (CoCO2 database), whereas several super-emitters from global inventories are likely incorrectly geolocated, which is likely because regional inventories provide large energy emitters as point sources including regional information on power plant locations. CoCO2-MOSAIC 1.0 is freely available at zenodo (10.5281/zenodo.7092358; Urraca et al., 2023) and at the JRC Data Catalogue (https://data.jrc.ec.europa.eu/dataset/6c8f9148-ce09-4dca-a4d5-422fb3682389, last access: 15 May 2023; Urraca Valle et al., 2023). © 2024 Ruben Urraca et al. |
| Review article: Drought as a continuum – memory effects in interlinked hydrological, ecological, and social systems | Natural Hazards and Earth System Sciences | Van Loon, A.; Kchouk, S.; Matanó, A.; Tootoonchi, F.; Alvarez-Garreton, C.; Hassaballah, K.; Wu, M.; Wens, M.; Shyrokaya, A.; Ridolfi, E.; Biella, R.; Nagavciuc, V.; Barendrecht, M.; Bastos, A.; Cavalcante, L.; de Vries, F.; Garcia, M.; Mård, J.; Streefkerk, I.; Teutschbein, C.; Tootoonchi, R.; Wees... | 2024 | Agua y Extremos; Cambio de Uso de Suelo | 10.5194/nhess-24-3173-2024 | https://doi.org/10.5194/nhess-24-3173-2024 | 3173-3205 | Vol: 24.0 Issue: 9.0 | 15618633 | Thomson Reuters ISI (SCIE) | Creative Commons Attribution 4.0 International | en | Droughts are often long-lasting phenomena, without a distinct start or end and with impacts cascading across sectors and systems, creating long-term legacies. Nevertheless, our current perceptions and management of droughts and their impacts are often event-based, which can limit the effective assessment of drought risks and reduction of drought impacts. Here, we advocate for changing this perspective and viewing drought as a hydrological–ecological–social continuum. We take a systems theory perspective and focus on how “memory” causes feedback and interactions between parts of the interconnected systems at different timescales. We first discuss the characteristics of the drought continuum with a focus on the hydrological, ecological, and social systems separately, and then we study the system of systems. Our analysis is based on a review of the literature and a study of five cases: Chile, the Colorado River basin in the USA, northeast Brazil, Kenya, and the Rhine River basin in northwest Europe. We find that the memories of past dry and wet periods, carried by both bio-physical (e.g. groundwater, vegetation) and social systems (e.g. people, governance), influence how future drought risk manifests. We identify four archetypes of drought dynamics: impact and recovery, slow resilience building, gradual collapse, and high resilience–big shock. The interactions between the hydrological, ecological, and social systems result in systems shifting between these types, which plays out differently in the five case studies. We call for more research on drought preconditions and recovery in different systems, on dynamics cascading between systems and triggering system changes, and on dynamic vulnerability and maladaptation. Additionally, we advocate for more continuous monitoring of drought hazards and impacts, modelling tools that better incorporate memories and adaptation responses, and management strategies that increase societal and institutional memory. This will help us to better deal with the complex hydrological–ecological–social drought continuum and identify effective pathways to adaptation and mitigation. Copyright: © 2024 Anne F. Van Loon et al. |
| A Relational Perspective to Environmental History: the Territorialization of Chepu's River Basin, Chiloé, Chile, 1982-2022; [Historia Ambiental con Perspectiva Relacional: La Territorialización de la Cuenca del Río Chepu, Chiloé, Chile 1982-2022] | Historia Ambiental Latinoamericana y Caribena | Vivanco, P.; Wells, G. | 2024 | Gobernanza e Interfaz Ciencia y Política | 10.32991/2237-2717.2024v14i1.p277-306 | https://www.halacsolcha.org/index.php/halac/article/view/725/710 | 277-306 | Vol: 14 Issue: 1 | 22372717 | Latindex | All Open Access; Gold Open Access | Spanish | This article presents the results of a research on the environmental history of a basin in southern Chile. Through historiographic and ethnographic work, the process of territorialization of the basin was reconstructed by analyzing processes of agroforestry colonization, conservationism and the irruption of extractive-business practices. The results show that aspects of the new Latin American rurality are territorialized through continuity, divergence and conflict in the relationships historically established in the territory. These are influenced by agents that, internally and externally, push these processes. The study concludes that the territorialization process addressed makes it possible to make visible the relevance of the relationships between human and non-human agents in the territory, to value the relationships made possible by animal and plant agents, and to contribute to the construction of a non-linear historical narrative that makes visible the complexity of environmental processes. © 2024 Centro Universitario de Anapolis. All rights reserved. |
| The Key Role of Temporal Stratification for GCM Bias Correction in Climate Impact Assessments | Earth's Future | Vásquez, N.; Mendoza, P.; Knoben, W.; Arnal, L.; Lagos-Zúñiga, M.; Clark, M.; Vargas, X. | 2024 | Zonas Costeras | 10.1029/2023EF004242 | https://doi.org/10.1029/2023EF004242 | arte2023EF004242 | Vol: 12.0 Issue: 8.0 | 23284277 | Thomson Reuters ISI (SCIE) | English | Characterizing climate change impacts on water resources typically relies on Global Climate Model (GCM) outputs that are bias-corrected using observational data sets. In this process, two pivotal decisions are (a) the Bias Correction Method (BCM) and (b) how to handle the historically observed time series, which can be used as a continuous whole (i.e., without dividing it into sub-periods), or partitioned into monthly, seasonal (e.g., 3 months), or any other temporal stratification (TS). Here, we examine how the interplay between the choice of BCM, TS, and the raw GCM seasonality may affect historical portrayals and projected changes. To this end, we use outputs from 29 GCMs belonging to the CMIP6 under the Shared Socioeconomic Pathway 5–8.5 scenario, using seven BCMs and three TSs (entire period, seasonal, and monthly). The results show that the effectiveness of BCMs in removing biases can vary depending on the TS and climate indices analyzed. Further, the choice of BCM and TS may yield different projected change signals and seasonality (especially for precipitation), even for climate models with low bias and a reasonable representation of precipitation seasonality during a reference period. Because some BCMs may be computationally expensive, we recommend using the linear scaling method as a diagnostics tool to assess how the choice of TS may affect the projected precipitation seasonality of a specific GCM. More generally, the results presented here unveil trade-offs in how BCMs are applied, regardless of the climate regime, urging the hydroclimate community to carefully implement these techniques. © 2024. The Author(s). | |
| Role of atmospheric rivers in shaping long term Arctic moisture variability | Nature Communications | Wang, Z.; Ding, Q.; Wu, R.; Ballinger, T.; Guan, B.; Bozkurt, D.; Nash, D.; Baxter, I.; Topál, D.; Li, Z.; Huang, G.; Chen, W.; Chen, S.; Cao, X.; Chen, Z. | 2024 | Zonas Costeras | 10.1038/s41467-024-49857-y | https://doi.org/10.1038/s41467-024-49857-y | art5505 | Vol: 15.0 Issue: 1.0 | 20411723 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Atmospheric rivers (ARs) reaching high-latitudes in summer contribute to the majority of climatological poleward water vapor transport into the Arctic. This transport has exhibited long term changes over the past decades, which cannot be entirely explained by anthropogenic forcing according to ensemble model responses. Here, through observational analyses and model experiments in which winds are adjusted to match observations, we demonstrate that low-frequency, large-scale circulation changes in the Arctic play a decisive role in regulating AR activity and thus inducing the recent upsurge of this activity in the region. It is estimated that the trend in summertime AR activity may contribute to 36% of the increasing trend of atmospheric summer moisture over the entire Arctic since 1979 and account for over half of the humidity trends in certain areas experiencing significant recent warming, such as western Greenland, northern Europe, and eastern Siberia. This indicates that AR activity, mostly driven by strong synoptic weather systems often regarded as stochastic, may serve as a vital mechanism in regulating long term moisture variability in the Arctic. © The Author(s) 2024. |
| p2 The Extraordinary March 2022 East Antarctica “Heat” Wave. Part II: Impacts on the Antarctic Ice Sheet | Journal of Climate | Wille, J.; Alexander, S.; Amory, C.; Baiman, R.; Barthélemy, L.; Bergstrom, D.; Berne, A.; Binder, H.; Blanchet, J.; Bozkurt, D.; Bracegirdle, T.; Casado, M.; Choi, T.; Clem, K.; Codron, F.; Datta, R.; Di Battista, S.; Favier, V.; Francis, D.; Fraser, A.; Fourré, E.; Garreaud, R.; Genthon, C.; Gorod... | 2024 | Agua y Extremos; Zonas Costeras | 10.1175/JCLI-D-23-0176.1 | https://doi.org/10.1175/JCLI-D-23-0176.1 | 779-799 | Vol: 37.0 Issue: 3.0 | 08948755 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Between 15 and 19 March 2022, East Antarctica experienced an exceptional heat wave with widespread 308–408C temperature anomalies across the ice sheet. In Part I, we assessed the meteorological drivers that generated an intense atmospheric river (AR) that caused these record-shattering temperature anomalies. Here, we continue our large collaborative study by analyzing the widespread and diverse impacts driven by the AR landfall. These impacts included widespread rain and surface melt that was recorded along coastal areas, but this was outweighed by widespread high snowfall accumulations resulting in a largely positive surface mass balance contribution to the East Antarctic region. An analysis of the surface energy budget indicated that widespread downward longwave radiation anomalies caused by large cloud-liquid water contents along with some scattered solar radiation produced intense surface warming. Isotope measurements of the moisture were highly elevated, likely imprinting a strong signal for past climate reconstructions. The AR event attenuated cosmic ray measurements at Concordia, something previously never observed. Last, an extratropical cyclone west of the AR landfall likely triggered the final collapse of the critically unstable Conger Ice Shelf while further reducing an already record low sea ice extent. © 2024 American Meteorological Society. |
| p1 The Extraordinary March 2022 East Antarctica “Heat” Wave. Part I: Observations and Meteorological Drivers | Journal of Climate | Wille, J.; Alexander, S.; Amory, C.; Baiman, R.; Barthélemy, L.; Bergstrom, D.; Berne, A.; Binder, H.; Blanchet, J.; Bozkurt, D.; Bracegirdle, T.; Casado, M.; Choi, T.; Clem, K.; Codron, F.; Datta, R.; Di Battista, S.; Favier, V.; Francis, D.; Fraser, A.; Fourré, E.; Garreaud, R.; Genthon, C.; Gorod... | 2024 | Agua y Extremos; Zonas Costeras | 10.1175/JCLI-D-23-0175.1 | https://doi.org/10.1175/JCLI-D-23-0175.1 | 757-778 | Vol: 37.0 Issue: 3.0 | 08948755 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Between 15 and 19 March 2022, East Antarctica experienced an exceptional heat wave with widespread 30°–40°C temperature anomalies across the ice sheet. This record-shattering event saw numerous monthly temperature records being broken including a new all-time temperature record of -9.4°C on 18 March at Concordia Station despite March typically being a transition month to the Antarctic coreless winter. The driver for these temperature extremes was an intense atmospheric river advecting subtropical/midlatitude heat and moisture deep into the Antarctic interior. The scope of the temperature records spurred a large, diverse collaborative effort to study the heat wave’s meteorological drivers, impacts, and historical climate context. Here we focus on describing those temperature records along with the intricate meteorological drivers that led to the most intense atmospheric river observed over East Antarctica. These efforts describe the Rossby wave activity forced from intense tropical convection over the Indian Ocean. This led to an atmospheric river and warm conveyor belt intensification near the coastline, which reinforced atmospheric blocking deep into East Antarctica. The resulting moisture flux and upper-level warm-air advection eroded the typical surface temperature inversions over the ice sheet. At the peak of the heat wave, an area of 3.3 million km2 in East Antarctica exceeded previous March monthly temperature records. Despite a temperature anomaly return time of about 100 years, a closer recurrence of such an event is possible under future climate projections. In Part II we describe the various impacts this extreme event had on the East Antarctic cryosphere. © 2024 American Meteorological Society. |
| Climate projections of oceanographic variables in the Exclusive Economic Zone of Ecuador: A 21st century perspective to inform impact and adaptation assessment | Regional Studies in Marine Science | Winckler, P.; Farías, L.; Vicuña, S.; Esparza, C.; Mora, J.; Chubretovic, R.; Cabrera, F.; Zambrano-Sánchez, N.; Caza, P.; González, R. | 2024 | Zonas Costeras | 10.1016/j.rsma.2024.103612 | https://doi.org/10.1016/j.rsma.2024.103612 | art103612 | Vol: 77.0 | 23524855 | Thomson Reuters ISI (SCIE) | English | Climate projections of ocean variables are essential to inform adaptation strategies and plans involving open and coastal oceanic regions. Assessment of baseline and projections of sea surface temperature (SST), pH, dissolved oxygen (DO), mean sea level (MSL), waves coastal flooding within Ecuador's Exclusive Economic Zone, including Galapagos Islands are reported herein. With different magnitudes of change, both near-future (2021–2050) and far-future projections (2051–2080) show a statistically robust increase in SST, MSL rise and a reduction in pH, a proxy for acidification. In contrast, DO decrease is only observed in surface (0–100 m) but not in subsurface waters (100–400 m). The likelihood of extreme sea level events in the coastal cities of La Libertad, Manta and Esmeraldas would remain almost unchanged for near-future projections (2026–2045) whereas, for end-of-century projections (2081–2100), historical 1 in a 100-year extreme flooding events would become yearly occurrences. The generated data product offers a state-of-the-art research and management tool for the 21st century under the combined stressors of global climate change. Since the eastern Tropical Pacific Ocean is one of the most productive and biodiverse worldwide due to the equatorial upwelling system, possible impacts on marine biodiversity, social, and economic systems are discussed. © 2024 Elsevier B.V. | |
| Climate change impacts childhood | Medwave | Yohannessen, K. | 2024 | Ciudades Resilientes | 10.5867/medwave.2024.01.2805 | https://doi.org/10.5867/medwave.2024.01.2805 | e2805-e2805 | Vol: 24.0 Issue: 1.0 | 07176384 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | |
| When another one bites the dust: Environmental impact of global copper demand on local communities in the Atacama mining hotspot as registered by tree rings | Science of the Total Environment | Zanetta-Colombo, N.; Scharnweber, T.; Christie, D.; Manzano, C.; Blersch, M.; Gayo, E.; Muñoz, A.; Fleming, Z.; Nüsser, M. | 2024 | Agua y Extremos; Ciudades Resilientes | 10.1016/j.scitotenv.2024.170954 | https://doi.org/10.1016/j.scitotenv.2024.170954 | art170954 | Vol: 920.0 | 00489697 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Assessing the impact of mining activity on the availability of environmental pollutants is crucial for informing health policies in anticipation of future production scenarios of critical minerals essential for the transition to a net-zero carbon society. However, temporal and spatial monitoring is often sparse, and measurements may not extend far enough back in time. In this study, we utilize variations of chemical elements contained in tree-rings collected in local villages from an area heavily affected by copper mining in the Atacama Desert since the early 20th century to evaluate the temporal distribution of pollutants and their relationship with local drivers. By combining time-varying data on local drivers, such as copper production and the dry tailings deposit area, we show how the surge in copper production during the 1990s, fueled by trade liberalization and increased international demand, led to a significant increment in the availability of metal(loid)s related to mining activities on indigenous lands. Our findings suggest that the environmental legislation in Chile may be underestimating the environmental impact of tailing dams in neighboring populations, affecting the well-being of Indigenous Peoples from the Atacama mining hotspot region. We argue that future changes in production rates driven by international demand could have negative repercussions on the environment and local communities. Therefore, mining emissions and the management of tailing dams should be carefully considered to anticipate their potential negative effects on human and ecosystem health. © 2024 The Authors |
| Blowin’ in the Wind: Mapping the Dispersion of Metal(loid)s From Atacama Mining | GeoHealth | Zanetta‐Colombo, N.; Manzano, C.; Brombierstäudl, D.; Fleming, Z.; Gayo, E.; Rubinos, D.; Jerez, Ó.; Valdés, J.; Prieto, M.; Nüsser, M. | 2024 | Ciudades Resilientes | 10.1029/2024gh001078 | https://doi.org/10.1029/2024gh001078 | arte2024GH001078 | Vol: 8.0 Issue: 10.0 | 2471-1403 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | en | The Atacama Desert’s naturally elevated metal(loid)s pose a unique challenge for assessing the environmental impact of mining, particularly for indigenous communities residing in these areas. This study investigates how copper mining influences the dispersion of these elements in the wind-transportable fraction (<75 μm) of surface sediments across an 80 km radius. We employed a multi-pronged approach, utilizing spatial modeling to map element distributions, exponential decay analysis to quantify concentration decline with distance, regime shift modeling to identify dispersion pattern variations, and pollution assessment to evaluate impact. Our results reveal significant mining-driven increases in surface concentrations of copper (Cu), molybdenum (Mo), and arsenic (As). Notably, within the first 20 km, concentrations peaked at 1,016 mg kg⁻1 for Cu, 31 mg kg⁻1 for Mo, and a remarkable 165 mg kg⁻1 for As. Cu and Mo displayed significant dispersion, extending up to 50 km from the source. However, As exhibited the most extensive reach, traveling up to 70 km downwind, highlighting the far-reaching ecological footprint of mining operations. Mineralogical analyses corroborated these findings, identifying mining-related minerals in surface sediments far beyond the immediate mining area. Although pollution indices based on the proposed Local Geochemical Background reveal significant contamination across the study area, establishing accurate pre-industrial baseline values is essential for a more reliable assessment. This study challenges the concept of “natural pollution” by demonstrating that human activities exacerbate baseline metal(loid)s levels. Expanding monitoring protocols is imperative to comprehensively assess the combined effects of multiple emission sources, including mining and natural processes, in safeguarding environmental and human health for future generations. |
| Advances and knowledge gaps on climate change impacts on honey bees and beekeeping: A systematic review | Global Change Biology | Zapata-Hernández, G.; Gajardo-Rojas, M.; Calderón-Seguel, M.; Muñoz, A.; Yáñez, K.; Requier, F.; Fontúrbel, F.; Ormeño-Arriagada, P.; Arrieta, H. | 2024 | Agua y Extremos | 10.1111/gcb.17219 | https://doi.org/10.1111/gcb.17219 | arte17219 | Vol: 30.0 Issue: 3.0 | 13541013 | Thomson Reuters ISI (SCIE) | English | The Western honey bee Apis mellifera is a managed species that provides diverse hive products and contributing to wild plant pollination, as well as being a critical component of crop pollination systems worldwide. High mortality rates have been reported in different continents attributed to different factors, including pesticides, pests, diseases, and lack of floral resources. Furthermore, climate change has been identified as a potential driver negatively impacting pollinators, but it is still unclear how it could affect honey bee populations. In this context, we carried out a systematic review to synthesize the effects of climate change on honey bees and beekeeping activities. A total of 90 articles were identified, providing insight into potential impacts (negative, neutral, and positive) on honey bees and beekeeping. Interest in climate change's impact on honey bees has increased in the last decade, with studies mainly focusing on honey bee individuals, using empirical and experimental approaches, and performed at short-spatial (<10 km) and temporal (<5 years) scales. Moreover, environmental analyses were mainly based on short-term data (weather) and concentrated on only a few countries. Environmental variables such as temperature, precipitation, and wind were widely studied and had generalized negative effects on different biological and ecological aspects of honey bees. Food reserves, plant-pollinator networks, mortality, gene expression, and metabolism were negatively impacted. Knowledge gaps included a lack of studies at the apiary and beekeeper level, a limited number of predictive and perception studies, poor representation of large-spatial and mid-term scales, a lack of climate analysis, and a poor understanding of the potential impacts of pests and diseases. Finally, climate change's impacts on global beekeeping are still an emergent issue. This is mainly due to their diverse effects on honey bees and the potential necessity of implementing adaptation measures to sustain this activity under complex environmental scenarios. © 2024 John Wiley & Sons Ltd. | |
| Variability in oceanographic conditions affecting Mesophotic Ecosystems along the South Eastern Pacific: Latitudinal trends and potential for climate refugia | Journal of Marine Systems | de la Maza, L.; Wieters, E.; Beldade, R.; Landaeta, M.; Perez-Matus, A.; Navarrete, S. | 2024 | Zonas Costeras | 10.1016/j.jmarsys.2024.103999 | https://doi.org/10.1016/j.jmarsys.2024.103999 | art103999 | Vol: 245.0 | 09247963 | Thomson Reuters ISI (SCIE) | English | Oceans have been changing at the fastest pace since the beginning of the Holocene. The South Eastern Pacific (SEP), including the Humboldt Upwelling Ecosystem (HUE) is subject to changes in upwelling winds, temperature, El Niño, and the ever-increasing local anthropogenic stressors, all of which have been documented for surface coastal waters where in-situ and remote observations are readily available. Temporal and spatial changes in the adjacent deeper waters where diverse Mesophotic Ecosystems are found have been scarcely documented. These marine ecosystems have been the focus of ecological studies for less than two decades. Here we provide an overview of the thermal variability at mesophotic depths and assess their potential as climatic refugia along all SEP ecoregions. We analyzed a time series of temperature and salinity from a 19 yr reanalysis based on remote and in-situ observations (CTD, ARGO, XBTs, moorings) to quantify variability in the Tropical (0–5°S), Northern Warm Temperate (5–30°S); Southern Warm Temperate (30–39.5°S) and Magellanic subregions (39.5–45°S), at two mesophotic depth strata (50 and 100 m), and a reference surface (5 m) depth. We assessed variability in the seasonal, interannual (El Niño) and ‘long-term’ (ca. 20 yr) scales, and the relationship with wind velocities. The thermal depth gradient between surface and mesophotic depths did not change smoothly with latitude but peaked within the northern portion of the warm temperate subregion, decreasing towards lower and higher latitudes. Seasonal variation in temperature was also largest in the north and south temperate subregions and minimal in the Magellanic subregion. Depth dampening of seasonal temperature variation was also strengthened at intermediate latitudes and much reduced in the tropics, where seasonal variation at mesophotic depths was similar to that at the surface. The strong interannual El Niño events were identified at all depths in tropical and temperate subregions, with stronger standardized effects at mesophotic layers than at the surface. Long-term (ca. two decades) temperature trends were significant and changed direction from warming to cooling along the SEP but were generally patchier at mesophotic layers. Spatial temperature gradients have remained relatively stable over the past two decades and were stronger at the surface than at mesophotic depths, and stronger within the tropics than in all other subregions. Surprisingly, the velocity of climate change was patchier and generally faster at mesophotic layers than at the surface. We conclude that, judging solely by physical environmental conditions, mesophotic ecosystems may be used by species with very different temperature affinities in temperate subregions, while in the tropics, more overlap in temperature affinities of component species may be found. Importantly, while the seasonal amplitude is reduced at mesophotic depth in most subregions, except the tropics, interannual disturbances affect mesophotic depths at least as strongly as they do surface waters and climate change velocities are faster at mesophotic depths than at surface. Thus, these ecosystems are not sheltered from inter-annual and longer-term forcing and their biotas might be more vulnerable to climate change than shallow coastal ecosystems. © 2024 Elsevier B.V. | |
| The influence of human activities on streamflow reductions during the megadrought in central Chile | Hydrology and Earth System Sciences | Álamos, N.; Alvarez-Garreton, C.; Muñoz, A.; González-Reyes, Á. | 2024 | Agua y Extremos | 10.5194/hess-28-2483-2024 | https://doi.org/10.5194/hess-28-2483-2024 | 2483-2503 | Vol: 28.0 Issue: 11.0 | 10275606 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Since 2010, central Chile has experienced a protracted megadrought with annual precipitation deficits ranging from 25 % to 70 %. An intensification of drought propagation has been attributed to the effect of cumulative precipitation deficits linked to catchment memory. Yet, the influence of water extractions on drought intensification is still unclear. Our study assesses climate and water use effects on streamflow reductions during a high-human-influence period (1988–2020) in four major agricultural basins. We performed this attribution by contrasting observed streamflow (driven by climate and water use) with near-natural streamflow simulations (driven mainly by climate) representing what would have occurred without water extractions. Near-natural streamflow estimations were obtained from rainfall–runoff models trained over a reference period with low human intervention (1960–1988). Annual and seasonal streamflow reductions were examined before and after the megadrought onset, and hydrological drought events were characterized for the complete evaluation period in terms of their frequency, duration, and intensity. Our results show that before the megadrought onset (1988–2009) the mean annual deficits in observed streamflow ranged between 2 % and 20 % across the study basins and that 81 % to 100 % of those deficits were explained by water extractions. During the megadrought (2010–2020), the mean annual deficits in observed streamflow were 47 % to 76 % among the basins. During this time, the relative contribution of precipitation deficits on streamflow reduction increased while the contribution of water extractions decreased, accounting for 27 % to 51 % of the streamflow reduction. Regarding drought events during the complete evaluation period, we show that human activities have amplified drought propagation, with almost double the intensity of hydrological droughts in some basins compared to those expected by precipitation deficits only. We conclude that while the primary cause of streamflow reductions during the megadrought has been the lack of precipitation, water uses have not diminished during this time, causing an exacerbation of the hydrological drought conditions and aggravating their impacts on water accessibility in rural communities and natural ecosystems. © Author(s) 2024. |
| Hydroclimate variability in the Tropical Andes recorded by δ18O isotopes from a new network of Polylepis tarapacana tree-rings | Global and Planetary Change | Álvarez, C.; Christie, D.; González-Reyes, Á.; Veblen, T.; Helle, G.; LeQuesne, C.; Rodriguez-Caton, M.; Szejner, P.; Flores-Sáez, F.; Gipoulou-Zúñiga, T.; Suazo-Álvarez, M.; Muñoz-Salazar, T.; Aliste, D.; Morales, M.; Muñoz, A.; Villalba, R. | 2024 | Agua y Extremos | 10.1016/j.gloplacha.2024.104503 | https://doi.org/10.1016/j.gloplacha.2024.104503 | art104503 | Vol: 239.0 | 09218181 | Thomson Reuters ISI (SCIE) | English | Stable oxygen isotopes records (δ18O) in tree-rings are commonly used to assess the response of trees to environmental variability being a valuable tool for studying past climate at different temporal and spatial scales. This is particularly relevant in semi-arid regions like the southern Tropical Andes, where ongoing environmental changes coincide with a rapidly increasing demand for hydrological resources, presenting a challenge for ecosystem dynamics and water resource management. In this study, we aim to determine the main spatio-temporal variability of a new network of δ18O Polylepis tarapacana chronologies during the last century, and their relationships with hydroclimate and tropical circulation at local to subcontinental scales throughout the Tropical Andes. For this purpose, we develop six δ18O P. tarapacana tree-ring chronologies across a 450 km latitudinal moisture gradient in the southern Tropical Andes adjacent to the Atacama Desert, covering the period 1900–2007. Results show a clear latitudinal gradient in the δ18O values across the network and significant relationships are observed with other δ18O tree-ring chronologies in Tropical South America, demonstrating clear regional climate influences at a subcontinental scale. A principal component analysis of the δ18O tree-ring chronologies demonstrate a strong regional environmental signal contained in the network, exhibiting a main temporal pattern (PC1 δ18O) that explains 63% of the total variance during the period 1900–2007. Comparisons between PC1 δ18O and environmental variables showed significant negative relationships with precipitation and soil moisture, and positive relationships with temperature and vapor pressure deficit (VPD) during summer when the South American monsoon occurs. The main δ18O tree-ring network signal clearly records tropical atmospheric and circulation patterns across South America. The easterly wind flux conditions from the Amazon basin favor lower δ18O values, and the PC1 δ18O exhibit significant positive correlations with VPD across the entire Tropical Andes and the northern portion of the Amazon basin, and as well as outgoing longwave radiation across the southern Tropical Andes and part of the Amazon basin. The close relationships between the regional signals from our δ18O tree-ring network with the previously mentioned parameters, highlight the potential to develop future hydroclimatic-related reconstructions with these δ18O records to assess climate variability and change across the Tropical Andes. © 2023 | |
| Snow Cover Reconstruction in the Brunswick Peninsula, Patagonia, Derived from a Combination of the Spectral Fusion, Mixture Analysis, and Temporal Interpolation of MODIS Data | Remote Sensing | Aguirre, F.; Bozkurt, D.; Sauter, T.; Carrasco, J.; Schneider, C.; Jaña, R.; Casassa, G. | 2023 | Zonas Costeras | 10.3390/rs15225430 | https://doi.org/10.3390/rs15225430 | art5430 | Vol: 15 Issue: 22 | 20724292 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Several methods based on satellite data products are available to estimate snow cover properties, each one with its pros and cons. This work proposes and implements a novel methodology that integrates three main processes applied to MODIS satellite data for snow cover property reconstruction: (1) the increase in the spatial resolution of MODIS (MOD09) data to 250 m using a spectral fusion technique; (2) a new proposal of snow-cloud discrimination; (3) the daily spatio-temporal reconstruction of snow extent and its albedo signature using the endmembers extraction and spectral mixture analyses. The snow cover reconstruction method was applied to the Brunswick Peninsula, Chilean Patagonia, a low-elevation (<1500 m a.s.l.) mid-latitude area. The results show a 98% agreement between MODIS snow detection and ground-based snow measurements at the automatic weather station, Tres Morros (53.3174°S, 71.2790°W), with fractional snow cover values between 20% and 50%, showing a close relationship between snow and vegetation type. The number of snow days compiled from the MODIS data indicates a good performance (Pearson’s correlation of 0.9) compared with the number of skiing days at the Cerro Mirador ski center, Punta Arenas. Although the number of seasonal snow days showed a significant increasing trend of 0.54 days/year in the Brunswick Peninsula during the 2000–2020 period, a significant decrease of −4.64 days/year was detected in 2010–2020. © 2023 by the authors. |
| The influence of human activities on streamflow reductions during the megadrought in central Chile | Alamos, N.; Alvarez-Garreton, C.; Muñoz, A.; González-Reyes, A. | 2023 | 10.5194/hess-2023-246 | https://hess.copernicus.org/preprints/hess-2023-246/ | English | Abstract. Central Chile has experienced a protracted megadrought since 2010 (up to date), with annual precipitation deficits ranging from 25 % to 70 %. Drought propagation has been intensified during this time, with streamflow reductions up to 30 % larger than those expected from historical records. This intensification has been attributed to the cumulative effect of precipitation deficits associated to catchment memory in near-natural basins of central Chile. However, the additional effect of water extractions on drought intensification in disturbed basins remains an open challenge. In this study, we assess the effects of climate and water use on streamflow reductions during the last three decades in four major agricultural basins in central Chile, with particular focus on the ongoing megadrought. We address this by contrasting streamflow observations with near-natural streamflow simulations representing the discharge that would have occurred without water extractions. Near-natural streamflow estimations are obtained from rainfall-runoff models trained over a reference period with low human intervention (1960–1988). We characterise hydrological droughts driven by precipitation and human activities during the evaluation period (1988–2020) in terms of the frequency, duration and intensity of near-natural and observed seasonal streamflow deficits, respectively. Our results show that before the megadrought onset (1988–2009), streamflow in the four basins was 2 to 20 % lower than the streamflow during the undisturbed period. Between 81 to 100 % of these larger deficits were explained by water extractions. During the megadrought (2010–2020), streamflow was reduced in a range of 47 to 76 % among the different basins, compared to the reference period. During this time, the climatic contribution to streamflow reductions increased and had a lower relative contribution, accounting for 27 to 51 % of streamflow reduction. During the complete evaluation period, human activities have amplified the propagation of droughts, with more than double the frequency, duration, and intensity of hydrological droughts in some basins, compared to those expected by precipitation deficits only. We conclude that while the primary cause of streamflow reductions during the megadrought has been the lack of precipitation, water uses have not diminished during this time, causing an exacerbation of the hydrological drought conditions and aggravating their impacts on human water consumption, economic activities, and natural ecosystems. | |||||||
| High resolution urban climatic risk impact maps in Gran Valparaiso, Chile | Alamos, N.; Videla, J.; Madariaga, M.; Gajardo, V.; Muñoz, A.; Billi, M.; Amigo, C. | 2023 | 10.17605/OSF.IO/E7FPY | https://osf.io/e7fpy/ | Open Science Framework | This collection of maps contains a set of 6 layers assessing the risk of the population of the Gran Valparaíso conurbation (Chile) in the face of threats of extreme heat, storm surges, floods, forest fires, landslides, and Droughts. The maps have a resolution at the Chilean census block level. The layers show as available attributes the overall level of risk and its components: threat (A), exposure (E), sensitivity (S), and response capacity (CR). To estimate the risk, A, E, S, and CR indices are combined through a fuzzy logic methodology, which considers using causality rules co-constructed and validated with local experts and stakeholders. It should be considered that the values presented by each census block on the maps represent an ordering of risk (and of A, E, S, and CR), where higher values indicate a greater risk than apples with lower values. The results are ordinal, ranging from mild, through moderately mild, to moderate, high, or very high. Moreover, they are not absolute values but relative to the specific case study and should not be comparable or extrapolated to other study areas. This Work is an actualization of what is presented by Alamos, N., Billi, M., Amigo, C., Urquiza, A., Winckler, P., Larraguibel, C., … Valdebenito, C. (2022, March 23). Fuzzy logic modeling to assess high-resolution spatial urban climatic risk impact in Valparaiso, Chile. https://doi.org/10.17605/OSF.IO/2XTVS Español Esta colección de mapas contiene un conjunto de 6 capas que evalúan el riesgo de la población de la connurbación del Gran Valparaíso (Chile) ante amenazas de calor extremo, marejadas, inundaciones, incendios forestales, deslizamientos y sequías. Los mapas tienen una resolución a nivel de manzana censal. Las capas muestran como atributos disponibles el nivel global de riesgo y sus componentes: amenaza (A), exposición (E), sensibilidad (S) y capacidad de respuesta (CR). Para estimar el riesgo, los índices de A, E, S y CR se combinan a través de una metodología de lógica difusa, que considera el uso de reglas de causalidad co-construidas y validadas con expertos locales y partes interesadas. Se debe considerar que los valores que presenta cada manzana censal en los mapas representan un ordenamiento de riesgo (y de A, E, S y CR), donde los valores más altos indican mayor riesgo que las manzanas con valores más bajos. Los resultados son ordinales, que van desde leves, pasando por moderadamente leves, hasta moderados, altos o muy altos. Además, no son valores absolutos, sino relativos al caso de estudio específico y no deben ser comparables ni extrapolables a otras áreas de estudio. Este Trabajo es una actualización de lo presentado por Alamos, N., Billi, M., Amigo, C., Urquiza, A., Winckler, P., Larraguibel, C., … Valdebenito, C. (2022, March 23). Fuzzy logic modelling to assess high resolution spatial urban climatic risk impact in Valparaiso, Chile. https://doi.org/10.17605/OSF.IO/2XTVS omparables ni extrapolables a otras áreas de estudio. Este Trabajo es una actualización de lo presentado por Alamos, N., Billi, M., Amigo, C., Urquiza, A., Winckler, P., Larraguibel, C., … Valdebenito, C. (2022, March 23). Fuzzy logic modelling to assess high resolution spatial urban climatic risk impact in Valparaiso, Chile. https://doi.org/10.17605/OSF.IO/2XTVS omparables ni extrapolables a otras áreas de estudio. Este Trabajo es una actualización de lo presentado por Alamos, N., Billi, M., Amigo, C., Urquiza, A., Winckler, P., Larraguibel, C., … Valdebenito, C. (2022, March 23). Fuzzy logic modelling to assess high resolution spatial urban climatic risk impact in Valparaiso, Chile. https://doi.org/10.17605/OSF.IO/2XTVS | |||||||
| Dendroecological analysis of the remote endemic Nothomyrcia fernandeziana forests of Robinson Crusoe Island in the Southeast Pacific | Dendrochronologia | Almonacid, P.; Rojas-Badilla, M.; LeQuesne, C.; Muñoz-Salazar, T.; Christie, D. | 2023 | Agua y Extremos | 10.1016/j.dendro.2023.126129 | https://doi.org/10.1016/j.dendro.2023.126129 | art126129 | Vol: 81 | 11257865 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Juan Fernández Archipelago National Park is located in the Southeast Pacific Ocean ∼670 km off the coast of Chile. Composed by three islands, encompasses an ecosystem with 208 native plant species of which 64% are endemic. Robinson Crusoe Island (RCI) is the largest and the only with a permanent human population. Among the tree species of RCI, Nothomyrcia fernandeziana is the most abundant and dominant forming part of this fragile forest ecosystem. Despite this, there is very little information regarding its autoecology and conservation. Therefore, the objective of this work was to determine the radial growth patterns of N. fernandeziana and its longevity using dendrochronological methods. For this purpose, cross sections of trees blown down by wind were collected in conjunction with park rangers from five different sites and analyzed using tree-ring methods. Our results confirm that N. fernandeziana is a shade-tolerant species capable of maintaining extremely low initial growth rates under the canopy for several decades. Individual growth series were found to respond rapidly to changes in environmental conditions, revealed by abrupt positive and negative changes in their annual growth. Our data indicate a longevity of up to 450 years, with one N. fernandeziana individual established in the mid XVII century before the arrival of humans to the pristine island ecosystem. The results of this study are essential to strengthen RCI conservation plans considering restoration actions based on the autoecology of this rare endemic tree species, and the control of exotic invasive species that presently threatens the RCI forests ecosystems. © 2023 Elsevier GmbH |
| Informe a las Naciones: Seguridad hídrica en Chile: Caracterización y perspectivas de futuro | Alvarez-Garreton, C.; Blanco, G.; Boisier, J.; Nicolas Artero, C.; Maillet, A.; Aldunce, P.; Urrutia-Jalabert, R.; Zambrano-Bigiarini, M.; Guevara, G.; Galleguillos, M.; Muñoz, A.; Christie, D.; Marinao, R.; Garreaud, R. | 2023 | https://www.cr2.cl/seguridadhidrica/ | 76 | cr2.cl | Spanish | La seguridad hídrica se define como la posibilidad de acceder al agua en cantidad y calidad adecuadas para el sustento humano, la salud y el desarrollo socioeconómico, considerando las particularidades ecosistémicas de cada cuenca y promoviendo la resiliencia frente a amenazas como la sequía, crecidas y la contaminación. Alcanzar la seguridad hídrica es un desafío complejo que requiere entender el sistema climático, su manifestación regional, su relación con las actividades humanas y contar con una gobernanza adecuada que se ciña al principio precautorio. Este informe reúne y sintetiza evidencia científica relevante para respaldar la toma de decisiones en esta materia, abordando la actual disponibilidad de agua en el país, sus proyecciones para finales del siglo XXI en un contexto de cambio climático, y las consideraciones legales y de gobernanza. El lanzamiento de este documento se llevó a cabo el 23 de noviembre de 2023 en el salón Gorbea de la Facultad de Ciencias Físicas y Matemáticas de la Universidad de Chile. |
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| Protecting environmental flows to achieve long-term water security | Journal of Environmental Management | Alvarez-Garreton, C.; Boisier, J.; Billi, M.; Lefort, I.; Marinao, R.; Barría, P. | 2023 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.1016/j.jenvman.2022.116914 | https://linkinghub.elsevier.com/retrieve/pii/S0301479722024872 | 116914 | Vol: 328 | 0301-4797 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | In this work, we propose a new approach to diagnose if a water allocation scheme is compatible with long-term water security at the catchment scale, and suggest steps to achieve such compatibility. We argue that when the remaining flow of a river after upstream withdrawals is not sufficient to safeguarding ecological river functions, the basin is at extreme risk of water scarcity, which indicates that the water management is failing. To test this, we analysed the water scarcity risks and the safeguarded environmental flows (e-flows) in 277 basins across a wide range of hydro-climatic conditions in Chile (17–55°S). For each basin, water scarcity risks were assessed based on water stress indices (WSIs, computed as the ratio of withdrawals to water availability), considering two water-use scenarios: (i) WSImax, where total withdrawals correspond to the maximum consumptive water allowed by the law, i.e., where only the e-flows protected by law remain in the river, and (ii) WSIalloc, where total withdrawals correspond to the actual allocated consumptive water uses within the basins. Further, we evaluated the adequacy of the water management system to protect ecological river functions by contrasting the e-flows protected in Chile with those safeguarded in six other countries. The water allocation system in Chile incorporated the protection of minimum e-flows in 2005 and established that these do not exceed 20% of the mean annual streamflow, except in some exceptional cases. This upper limit is consistently lower than the e-flows safeguarded in other countries, where 20%–80% of the mean annual streamflow are protected. This turns out in WSImax values between 80% and 100% in all basins, well above the threshold associated with over-committed basins under extreme risk of water scarcity (70% typically). When moving from the legally allowed to the actually allocated water use scenario, we found contrasting results: about 70% of the basins show low water scarcity risk (WSIalloc <40%), while an 18% have WSIalloc above 100%, indicating the allocation is going beyond current law limits and even beyond physical limits. Our results reveal that the link between e-flows, water allocation and water security has not been adequately incorporated in the current law. E-flows stipulated by law are insufficient to fulfil environmental requirements, while placing the basins under extreme risk of water scarcity if the total allowed withdrawals were exerted. To move towards a system that can effectively achieve long-term water security, we recommend: (i) To define tolerable water scarcity risks for basins, considering environmental requirements. (ii) To translate those risks into measurable basin indices to measure water security, such as the WSI. (iii) To set maximum water use limits (or minimum e-flows) within the basins that are compatible to the water security goals. If, under current and projected water availability conditions, the existing withdrawals exceed these limits, water managers should be able to adapt total consumption to the required limits. © 2022 The Authors |
| HESS Opinions: The unsustainable use of groundwater conceals a “Day Zero” | Alvarez-Garreton, C.; Boisier, J.; Garreaud, R.; González, J.; Rondanelli, R.; Gayó, E.; Zambrano-Bigiarini, M. | 2023 | 10.5194/hess-2023-245 | https://hess.copernicus.org/preprints/hess-2023-245/ | Abstract. Water scarcity is a pressing global issue driven by increasing water demands and changing climatic conditions. Based on novel estimates of water availability and water use, we examine the challenges and risks associated with groundwater (GW) withdrawals, focusing on the case of central-north Chile (27−35º S), where extreme water stress conditions prevail. As total water uses within a basin approaches the renewable freshwater resources, the dependence on GW reserves in unsustainable ways intensifies. This overuse has consequences that extend beyond mere resource depletion, manifesting into environmental degradation, societal conflict, and economic costs. We argue that the “Day Zero” scenario, often concealed by the hidden nature of GW resources, calls for a reconsideration of water allocation rules and a broader recognition of the long-term implications of unsustainable GW use. Our results offer insights for regions worldwide facing similar water scarcity challenges and emphasize the importance of proactive and sustainable water management strategies. | ||||||||
| Traditional crops and climate change adaptation: insights from the Andean agricultural sector | Climate and Development | Arias Montevechio, E.; Crispin Cunya, M.; Fernández Jorquera, F.; Rendon, E.; Vásquez-Lavin, F.; Stehr, A.; Ponce Oliva, R. | 2023 | Cambio de Uso de Suelo | 10.1080/17565529.2022.2151307 | https://www.tandfonline.com/doi/full/10.1080/17565529.2022.2151307 | 723-737 | Vol: 15 Issue: 9 | 1756-5529, 1756-5537 | Thomson Reuters ISI (SSCI) | English | The growth of traditional crops could be a primary resource for adapting to climate change and strengthening agrosystems’ resilience. However, these crops tend to be replaced by non-traditional crops with higher productivity, higher market values, and higher short-term income. In this context, smallholders face trade-offs between maximizing short-term income and ensuring resilience to face likely future climate adversities. The economic assessment of such trade-offs has been commonly neglected in the literature. Most studies are conducted using agronomic or anthropological frameworks to recognize the value of traditional agriculture to increase adaptive capacity and reduce vulnerability. This study fills this gap by assessing economic and agronomic trade-offs between traditional and non-traditional crops triggered by climate-induced changes in water availability. We also simulate the effectiveness of a water policy. Our results suggest that farmers growing traditional crops may get lower profits, but their portfolio is more resilient to climate change, whereas the water policy proves to be an effective adaptation strategy to climate change. However, the policy implementation could hinder the development of traditional crops. Based on our results, we suggest implementing smart agricultural policies to balance economic, cultural, and adaptation goals. © 2023 Informa UK Limited, trading as Taylor & Francis Group. | |
| On the time scale of meteorological, soil moisture, and snow drought indices to assess streamflow drought over catchments with different hydrological regime: a case study using a hundred Chilean catchments | Baez-Villanueva, O.; Zambrano-Bigiarini, M.; Miralles, D.; Beck, H.; Siegmund, J.; Alvarez-Garreton, C.; Verbist, K.; Garreaud, R.; Boisier, J.; Galleguillos, M. | 2023 | 10.5194/egusphere-2023-1911 | https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1911/ | Abstract. A wide variety of drought indices exist today without consensus on suitable indices and temporal scales for monitoring streamflow drought across diverse hydrological settings. Considering the growing interest in spatially-distributed indices for ungauged areas, this study addresses the following questions: i) what temporal scales of precipitation-based indices are most adequate to assess streamflow drought in catchments with different hydrological regimes?, ii) do soil moisture indices outperform meteorological indices as proxies for streamflow drought?, iii) are snow indices more effective than meteorological indices for assessing streamflow drought in snow-influenced catchments? To answer these questions, we used one hundred near-natural catchments with four main types of hydrological regimes. The Standardised Precipitation Index (SPI), Standardised Precipitation and Evapotranspiration Index (SPEI), Empirical Standardised Soil Moisture Index (ESSMI), and standardised Snow Water Equivalent Index (SWEI) were computed across various time scales over the catchments for 1979–2020. Cross-correlation and event coincidence analysis were applied between these indices and the Standardised Streamflow Index at a temporal scale of one month (SSI-1), as representative of streamflow drought events. Finally, the linear correlation values and precursor coincidence rates were analysed for all catchments simultaneously, and separated by the hydrological regime. Our results indicate that i) there is no single meteorological, soil moisture, or snow drought index and temporal scale that could be used to characterise all streamflow droughts across Chile, and ii) the greater the snow influence in a catchment, the larger the temporal scale of the drought index to be used as proxy of streamflow drought. Finally, to avoid considering the influence of non-drought periods when analysing time series of drought indices, we suggest that future studies use the event coincidence analysis to evaluate which meteorological, soil moisture, and/or snow drought indices can be used as proxies of streamflow drought events. | ||||||||
| Sistema de simulación numérica para la costa de Chile central mediante el acoplamiento de modelos numéricos | Obras y Proyectos | Bahamóndez, S.; Aguirre, C. | 2023 | 10.21703/0718-281320233302 | https://revistas.ucsc.cl/index.php/oyp/article/view/2162/1463 | 1-8 | 07182805, 07182813 | SciELO; Dialnet; Latindex | Con la modelación numérica es posible anticipar condiciones de oleaje desfavorables para la actividad portuaria. Mediante modelos numéricos acoplados es factible incluir una mayor cantidad de variables, parámetros, procesos e interacciones con el objetivo de mejorar la representación y precisión de lo que ocurre en la realidad. En este trabajo se presenta un sistema de simulación numérica para la costa de Chile central mediante el acoplamiento del modelo de oleaje Wavewatch III (WW3) con el modelo hidrodinámico Coastal and Regional Ocean Community (CROCO) y el modelo atmosférico Weather Research and Forecasting (WRF). El sistema de modelación considera un acoplamiento unidireccional desde las variables de WRF que utilizan como entrada CROCO y WW3, además de un acoplamiento bidireccional entre los modelos CROCO y WW3. Este último se desarrolla a través de la implementación del software acoplador Ocean Atmosphere Sea Ice Soil (OASIS-MCT3) y el uso de las herramientas de acoplamiento facilitadas por CROCO. Los resultados son contrastados con observaciones instrumentales de oleaje realizadas por el Centro Nacional de Datos Hidrográficos y Oceanográficos de Chile (CENDHOC) a través de estadígrafos como el sesgo, error cuadrático medio y correlación. Las simulaciones acopladas hidrodinámicamente presentan un mejor grado de ajuste a las mediciones en comparación con las sin acoplamiento. En este sentido, los estadígrafos revelan un menor sesgo para las alturas significativas y direcciones medias acopladas. Asimismo, se obtienen mayores valores en los coeficientes de correlación de la altura de oleaje con acoplamiento hidrodinámico. | ||||
| Forest hydrology in Chile: Past, present, and future | Journal of Hydrology | Balocchi, F.; Galleguillos, M.; Rivera, D.; Stehr, A.; Arumi, J.; Pizarro, R.; Garcia-Chevesich, P.; Iroumé, A.; Armesto, J.; Hervé-Fernández, P.; Oyarzún, C.; Barría, P.; Little, C.; Mancilla, G.; Yépez, S.; Rodriguez, R.; White, D.; Silberstein, R.; Neary, D.; Ramírez de Arellano, P. | 2023 | Cambio de Uso de Suelo | 10.1016/j.jhydrol.2022.128681 | https://www.sciencedirect.com/science/article/pii/S0022169422012513 | 128681 | Vol: 616 | 00221694 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | This paper reviews the current knowledge of hydrological processes in Chilean temperate forests which extend along western South America from latitude 29° S to 56° S. This geographic region includes a diverse range of natural and planted forests and a broad sweep of vegetation, edaphic, topographic, geologic, and climatic settings which create a unique natural laboratory. Many local communities, endangered freshwater ecosystems, and downstream economic activities in Chile rely on water flows from forested catchments. This review aims to (i) provide a comprehensive overview of Chilean forest hydrology, to (ii) review prior research in forest hydrology in Chile, and to (iii) identify knowledge gaps and provide a vision for future research on forest hydrology in Chile. We reviewed the relation between native forests, commercial plantations, and other land uses on water yield and water quality from the plot to the catchment scale. Much of the global understanding of forests and their relationship with the water cycle is in line with the findings of the studies reviewed here. Streamflow from forested catchments increases after timber harvesting, native forests appear to use less water than plantations, and streams draining native forest yield less sediment than streams draining plantations or grassland/shrublands. We identified 20 key knowledge gaps such as forest groundwater systems, soil–plant-atmosphere interactions, native forest hydrology, and the effect of forest management and restoration on hydrology. Also, we found a paucity of research in the northern geographic areas and forest types (35-36°S); most forest hydrology studies in Chile (56%) have been conducted in the southern area (Los Rios Region around 39-40° S). There is limited knowledge of the geology and soils in many forested areas and how surface and groundwater are affected by changes in land cover. There is an opportunity to advance our understanding using process-based investigations linking field studies and modeling. Through the establishment of a forest hydrology science “society” to coordinate efforts, regional and national-scale land use planning might be supported. Our review ends with a vision to advance a cross-scale collaborative effort to use new nation-wide catchment-scale networks Long-term Ecosystem Research (LTER) sites, to promote common and complementary techniques in these studies, and to conduct transdisciplinary research to advance sound and integrated planning of forest lands in Chile. © 2022 The Author(s) |
| Effects of hydrogeochemistry on the microbial ecology of terrestrial hot springs | Microbiology Spectrum | Barbosa, C.; Tamayo-Leiva, J.; Alcorta, J.; Salgado, O.; Daniele, L.; Morata, D.; Díez, B. | 2023 | Zonas Costeras | 10.1128/SPECTRUM.00249-23 | https://doi.org/10.1128/SPECTRUM.00249-23 | 1-23 | Vol: 11 Issue: 5 | 21650497 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Temperature, pH, and hydrochemistry of terrestrial hot springs play a critical role in shaping thermal microbial communities. However, the interactions of biotic and abiotic factors at this terrestrial-aquatic interface are still not well understood on a global scale, and the question of how underground events influence microbial communities remains open. To answer this, 11 new samples obtained from the El Tatio geothermal field were analyzed by 16S rRNA amplicon sequencing (V4 region), along with 191 samples from previous publications obtained from the Taupo Volcanic Zone, the Yellowstone Plateau Volcanic Field, and the Eastern Tibetan Plateau, with their temperature, pH, and major ion concentration. Microbial alpha diversity was lower in acid-sulfate waters, and no significant correlations were found with temperature. However, moderate correlations were observed between chemical parameters such as pH (mostly constrained to temperatures below 70°C), SO42− and abundances of members of the phyla Armatimonadota, Deinococcota, Chloroflexota, Campilobacterota, and Thermoplasmatota. pH and SO42− gradients were explained by phase separation of sulfur-rich hydrothermal fluids and oxidation of reduced sulfur in the steam phase, which were identified as key processes shaping these communities. Ordination and permutational analysis of variance showed that temperature, pH, and major element hydrochemistry explain only 24% of the microbial community structure. Therefore, most of the variance remained unexplained, suggesting that other environmental or biotic factors are also involved and highlighting the environmental complexity of the ecosystem and its great potential to test niche theory ecological associated questions. Copyright © 2023 Barbosa et al. |
| Governance of Pandemics: why was it so easy? A proposal for the study of COVID-19 and climate change; [Gobernanza de la Pandemia: ¿por qué fue tan fácil?: Una propuesta para el estudio del COVID-19 y del cambio climático] | Revista Mad | Billi, M. | 2023 | Ciudades Resilientes | 10.5354/0719-0527.2023.73366 | https://revistamad.uchile.cl/index.php/RMAD/article/view/73366 | 1-18 | Issue: 49.0 | 07180527 | Thomson Reuters ISI (ESCI) | Spanish | We propose to compare the pandemics and climate change from the point of view of the governance challenges that both imply, and the strategies that have been implemented to respond to it. Specifically, we seek to understand why facing the pandemic appears to have been ‘easier’ than what has been the case with climate change, that is, why the public response to the phenomenon has managed to be so fast and effective, in relative terms, compared to many other dilemmas facing our contemporary society. To that purpose, we advance a comparative analysis model, inspired by Niklas Luhmann's Theory of Social Systems, which we call ‘governance prism’, structured along three dimensions (who governs? what is governed? what for? –or where– is it governed?). We also propose that different specific governance strategies can be characterized based on how these questions are answered. From this, some findings and transversal reflections are derived that, we hope, can serve as a guide to design better governance arrangements that better prepare us both to face the climate and environmental crisis that we are experiencing, as well as to face new hypothetical epidemic outbreaks that may arise in the future. © 2023 Universidad de Chile. All rights reserved. | |
| White Paper #1 | Race to Resilience Metrics Framework | Billi, M.; Borquez, R. | 2023 | https://www.cr2.cl/white-paper-1-race-to-resilience-metrics-framework/ | 38 | cr2.cl | Spanish | a campaña mundial Race to Resilience (RtR) está liderada por los High-Level Climate Champions y cuenta con el apoyo de un Equipo de Resiliencia, que incluye a la Secretaría Técnica del Centro del Centro de Ciencia del Clima y la Resiliencia CR2. La campaña también cuenta con el apoyo de dos órganos asesores independientes: el Grupo Asesor Metodológico (MAG) y el Grupo de Revisión de Expertos (ERG). RtR busca promover un cambio radical en la ambición y la acción global para la resiliencia climática, movilizando a actores no estatales con el objetivo de lograr la resiliencia de cuatro mil millones de personas vulnerables a los impactos del cambio climático a 2030. El marco de métricas de resiliencia de RtR ofrece un conjunto de herramientas para monitorear y evaluar eficazmente las acciones destinadas a generar resiliencia, con un énfasis específico en los actores no estatales. Este White Paper es la primera presentación del marco de métricas y fue preparado por la Secretaría Técnica de RtR alojada en el CR2. |
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| Reporte 2022 de la secretaría técnica de Race to Resilience | Billi, M.; Borquez, R.; Aldunce, P. | 2023 | https://www.cr2.cl/reporte-2022-de-la-secretaria-tecnica-de-race-to-resilience/ | 27 | cr2.cl | English | Este documento presenta el trabajo desarrollado por la secretaría técnica de Race to Resilience durante el año 2022, periodo donde se consolidó la relación con los socios de la campaña, además de fortalecer el sistema de evaluación y monitoreo para la resiliencia. Race to Resilience es una campaña de la Convención Marco de las Naciones Unidas sobre el Cambio Climático que busca impulsar la resiliencia climática a nivel mundial. La secretaría técnica de la campaña es liderada por el (CR)2 desde 2021. |
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| Temporal and Spatial Trends of Adverse Pregnancy and Birth Outcomes in a Sample of Births from a Public Hospital in Chile | Journal of Urban Health | Blanco, E.; Ruiz-Rudolph, P.; Yohannessen, K.; Ayala, S.; Quinteros, M.; Delgado-Saborit, J.; Blazquez, C.; Iglesias, V.; Zapata, D.; Bartington, S.; Harrison, R.; Ossa, X. | 2023 | Ciudades Resilientes | 10.1007/s11524-023-00733-y | https://doi.org/10.1007/s11524-023-00733-y | 513-524 | Vol: 100 | 1099-3460 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Understanding temporal and spatial trends in pregnancy and birth outcomes within an urban area is important for the monitoring of health indicators of a population. We conducted a retrospective cohort study of all births in the public hospital of Temuco, a medium-sized city in Southern Chile between 2009 and 2016 (n = 17,237). Information on adverse pregnancy and birth outcomes, as well as spatial and maternal characteristics (insurance type, employment, smoking, age, and overweight/obesity), was collected from medical charts. Home addresses were geocoded and assigned to neighborhood. We tested whether births and prevalence of adverse pregnancy outcomes changed over time, whether birth events were spatially clustered (Moran’s I statistic), and whether neighborhood deprivation was correlated to outcomes (Spearman’s rho). We observed decreases in eclampsia, hypertensive disorders of pregnancy, and small for gestational age, while gestational diabetes, preterm birth, and low birth weight increased over the study period (all p < 0.01 for trend), with little changes after adjusting for maternal characteristics. We observed neighborhood clusters for birth rate, preterm birth, and low birth weight. Neighborhood deprivation was negatively correlated with low birth weight and preterm birth, but not correlated with eclampsia, preeclampsia, hypertensive disorders of pregnancy, small for gestational age, gestational diabetes, nor stillbirth. Several encouraging downward trends and some increases in adverse pregnancy and birth outcomes, which, overall, were not explained by changes in maternal characteristics were observed. Identified clusters of higher adverse birth outcomes may be used to evaluate preventive health coverage in this setting. © 2023, The New York Academy of Medicine. |
| Las Crisis Del Carbón Y La Central Termoeléctrica Bocamina En Chile: Un Caso De Transición Energética Inversa | Historia 396 | Blanco, G.; Folchi, M.; Meier, S. | 2023 | https://historia396.cl/index.php/historia396/article/view/654 | 31-62 | Vol: 12 Issue: 2 | 0719-0719 | Thomson Reuters ISI (ESCI) | Spanish | El artículo explora un caso de transición energética inversa a partir de la instalación de la central termoeléctrica Bocamina en la zona carbonífera de la región de Concepción, Chile, durante la década de 1960. El caso demuestra cómo, en un contexto donde la hidroelectricidad experimentó un auge promovido por el Estado, se intentó revitalizar el carbón, luego de que el mineral fuera descartado como una opción viable para la producción eléctrica. La construcción de la Central Bocamina evidencia las complejas interacciones entre agentes políticos, laborales, geológicos y climáticos, posibilitando una comprensión no lineal de procesos de transición energética.Palabras clave: Coronel, transición energética, energía hidroeléctrica, carbón. | |||
| Engineering the catalytic activity of an Antarctic PET-degrading enzyme by loop exchange | Protein Science | Blázquez-Sánchez, P.; Vargas, J.; Furtado, A.; Griñen, A.; Leonardo, D.; Sculaccio, S.; Pereira, H.; Sonnendecker, C.; Zimmermann, W.; Díez, B.; Garratt, R.; Ramírez-Sarmiento, C. | 2023 | Zonas Costeras | 10.1002/pro.4757 | https://doi.org/10.1002/pro.4757 | arte4757 | Vol: 32 Issue: 9 | 09618368 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Several hydrolases have been described to degrade polyethylene terephthalate (PET) at moderate temperatures ranging from 25°C to 40°C. These mesophilic PET hydrolases (PETases) are less efficient in degrading this plastic polymer than their thermophilic homologs and have, therefore, been the subject of many protein engineering campaigns. However, enhancing their enzymatic activity through rational design or directed evolution poses a formidable challenge due to the need for exploring a large number of mutations. Additionally, evaluating the improvements in both activity and stability requires screening numerous variants, either individually or using high-throughput screening methods. Here, we utilize instead the design of chimeras as a protein engineering strategy to increase the activity and stability of Mors1, an Antarctic PETase active at 25°C. First, we obtained the crystal structure of Mors1 at 1.6 Å resolution, which we used as a scaffold for structure- and sequence-based chimeric design. Then, we designed a Mors1 chimera via loop exchange of a highly divergent active site loop from the thermophilic leaf-branch compost cutinase (LCC) into the equivalent region in Mors1. After restitution of an active site disulfide bond into this chimera, the enzyme exhibited a shift in optimal temperature for activity to 45°C and an increase in fivefold in PET hydrolysis when compared with wild-type Mors1 at 25°C. Our results serve as a proof of concept of the utility of chimeric design to further improve the activity and stability of PETases active at moderate temperatures. © 2023 The Protein Society. |
| CR2MET: A high-resolution precipitation and temperature dataset for the period 1960-2021 in continental Chile. | Boisier, J. | 2023 | 10.5281/zenodo.7529682 | https://zenodo.org/record/7529682 | Zenodo | Creative Commons Attribution 4.0 International | The Center for Climate and Resilience Research Meteorological dataset (CR2MET) includes two spatially-distributed products of daily precipitation and maximum/minimum near surface temperatures. The dataset covers the domain of continental Chile over a regular 0.05 degree latitude-longitude grid, and spans the period 1960-2021. Both a products are built on statistical models of the corresponding variables, calibrated against quality-controlled observational records. The CR2MET models are nurtured with a combination of data that includes different variables from ECMWF reanalysis ERA5, topographic parameters and land-surface temperature estimates from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensor. | ||||||
| Historical Reconstruction of Beekeeping Public Policies in Chile (1968-2022): Transitioning between a Protagonist State, State Withdrawal and Public-Private Articulation; [Reconstrucción histórica de las políticas públicas apícolas en Chile (1968-2022): transitando entre un Estado protagonista, el retiro estatal y la articulación público privada] | Cuadernos de Desarrollo Rural | Calderón-Seguel, M.; Muñoz, A.; Esper, E.; Sánchez, A.; Bravo, J.; Yáñez, K.; Zapata-Hernández, G.; Gajardo-Rojas, M.; Prieto, M.; Marchant Santiago, C.; Urquiza, A. | 2023 | Agua y Extremos; Ciudades Resilientes | 10.11144/Javeriana.cdr20.rhpp | https://doi.org/10.11144/Javeriana.cdr20.rhpp | Vol: 20.0 | 01221450 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | Spanish | Beekeeping worldwide and in Chile is an activity of great importance for the rural economy, the protection of the melliferous flora and food security, through pollination services. For this reason, international organizations and States consider it a strategic activity for rural development and, accordingly, recent policies formulated in Chile have subscribed to some of these perspectives. There are currently multiple threats to honey bees and other pollinators, which are expressed differently in different countries. Consequently, the study of beekeeping policies is of utmost relevance. In this article, through the analysis of archives and bibliographic sources, a historical reconstruction of the beekeeping policies promoted in Chile between 1968 and 2022 is carried out. Four stages were identified according to institutional designs, thematic orientations and scales of application. It concludes with the main challenges detected for the study of these policies in the country. © 2023, Pontificia Universidad Javeriana. All rights reserved. | |
| ENSO-Related Precipitation Variability in Central Chile: The Role of Large Scale Moisture Transport | Journal of Geophysical Research: Atmospheres | Campos, D.; Rondanelli, R. | 2023 | Zonas Costeras | 10.1029/2023JD038671 | https://doi.org/10.1029/2023JD038671 | arte2023JD038671 | Vol: 128 Issue: 17 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Interannual variability of precipitation in Central Chile has long been associated with changes in the dry atmospheric dynamics of the Southern Pacific. This is due to the interaction between the extratropical storm track and the polar anticyclonic circulations established by the Pacific South American (PSA) teleconnection mode, which results from changes in tropical convection. Here, we show that an enhanced subtropical moisture transport during the warm ENSO phase leads to an increase in the frequency of atmospheric rivers, larger values of precipitable water, and heightened zonal integrated water vapor transport. This occurs in a region of the Southern Pacific situated between the tropical high and the subtropical low of the PSA mode. These increases in zonal water vapor transport result in greater precipitation and moister, long-lived atmospheric rivers making landfall in Central Chile. © 2023. American Geophysical Union. All Rights Reserved. |
| Coastal territorialities and ontologies in friction: a review of multiple coastal settlements in the context of climate change | Journal of Coastal Conservation | Carrasco Henríquez, N.; Vergara-Pinto, F. | 2023 | Zonas Costeras | 10.1007/s11852-023-00947-x | https://doi.org/10.1007/s11852-023-00947-x | art: 17 | Vol: 27 Issue: 3 | 1400-0350 | Thomson Reuters ISI (SCIE) | English | Co-existence among multiple coastal settlements (MCS) following diverse ecological, economic, and cultural traditions drives to examine the territorial and ontological dimensions underlying the development of heterogeneous worldviews within common coastal geographies. In the case of the coastal zone in Chile, cultural diversity is evident as a historical field of dispute, which in the current context of adaptation to climate change may be reproducing or moving to other new trajectories. Using a literature review specifically on the case of the Arauco province in Chile, this article aims to identify a typology of multiple territorialities and ontologies interacting and being sustained by common coastal environments, although embedded in frictions and both structural and historical inequalities. Through thematic analysis framed in poststructuralist political ecology, this review identified three categories of territorialities that develop in the study area (i.e. colonial, intercultural, and interstitial). Each one leads to recognising the power dynamics that underlie the interactions of practices and discourses on the territory, the sea, and the conservation of nature. Results show that the historical predominance of modern ontology has produced permissible ways of being and moving through this geography. In contrast, resistance has been generated by other ways of living based on relational, traditional, and contemporaneous ontologies with discourses aimed at socio-ecological equilibrium. The current challenge is understanding these ontological frictions and interstices wherein multiple territorialities configured in a common coastal geography can co-exist and co-participate in climate change governance. © 2023, The Author(s), under exclusive licence to Springer Nature B.V. | |
| Main drivers of marine heat waves in the eastern South Pacific | Frontiers in Marine Science | Carrasco, D.; Pizarro, O.; Jacques-Coper, M.; Narváez, D. | 2023 | Zonas Costeras | 10.3389/fmars.2023.1129276 | https://doi.org/10.3389/fmars.2023.1129276 | art: 1129276 | Vol: 10 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | During the last decades, marine heat waves (MHWs) have increased in frequency and duration, with important impacts on marine ecosystems. This trend has been related to rising global sea surface temperatures, which are expected to continue in the future. Here, we analyze the main characteristics and possible drivers of MHWs in the eastern South Pacific off Chile. Our results show that MHWs usually exhibit spatial extensions on the order of 103-104 km2, temperature anomalies in the mixing layer between 1 and 1.3°C, and durations of 10 to 40 days, with exceptional events lasting several months. In this region, MHW are closely related to the ENSO cycles, in such a way that El Niño and, to a lesser extent, La Niña events increase the probability of high intensity and extreme duration MHWs. To analyze the MHW drivers, we use the global ocean reanalysis GLORYS2 to perform a heat budget in the surface mixed layer. We find that most events are dominated by diminished heat loss –associated with reduced evaporation– and enhanced insolation; thus, this group is called ASHF (for air-sea heat fluxes). The second type of MHWs is driven by heat advection, predominantly forced by anomalous eastward surface currents superimposed on a mean westward temperature gradient. The third type of MHWs results from a combination of positive (seaward) anomalies of air-sea heat fluxes and heat advection; this group exhibits the greatest values of spatial extension, intensity, and duration. Copyright © 2023 Carrasco, Pizarro, Jacques-Coper and Narváez. |
| A firebreak placement model for optimizing biodiversity protection at landscape scale | Journal of Environmental Management | Carrasco, J.; Mahaluf, R.; Lisón, F.; Pais, C.; Miranda, A.; de la Barra, F.; Palacios, D.; Weintraub, A. | 2023 | Cambio de Uso de Suelo | 10.1016/j.jenvman.2023.118087 | https://doi.org/10.1016/j.jenvman.2023.118087 | art: 118087 | Vol: 342 | 0301-4797 | Thomson Reuters ISI (SCIE) | English | A solution approach is proposed to optimize the selection of landscape cells for inclusion in firebreaks. It involves linking spatially explicit information on a landscape's ecological values, historical ignition patterns and fire spread behavior. A firebreak placement optimization model is formulated that captures the tradeoff between the direct loss of biodiversity due to the elimination of vegetation in areas designated for placement of firebreaks and the protection provided by the firebreaks from losses due to future forest fires. The optimal solution generated by the model reduced expected losses from wildfires on a biodiversity combined index due to wildfires by 30% relative to a landscape without any treatment. It also reduced expected losses by 16% compared to a randomly chosen solution. These results suggest that biodiversity loss resulting from the removal of vegetation in areas where firebreaks are placed can be offset by the reduction in biodiversity loss due to the firebreaks’ protective function. © 2023 Elsevier Ltd | |
| Climatic control of the surface mass balance of the Patagonian Icefields | Cryosphere | Carrasco-Escaff, T.; Rojas, M.; Garreaud, R.; Bozkurt, D.; Schaefer, M. | 2023 | Agua y Extremos; Zonas Costeras | 10.5194/tc-17-1127-2023 | https://doi.org/10.5194/tc-17-1127-2023 | 1127-1149 | Vol: 17 Issue: 3 | 1994-0416 | Thomson Reuters ISI (SCIE) | English | The Patagonian Icefields (Northern and Southern Patagonian Icefield) are the largest ice masses in the Andes Cordillera. Despite its importance, little is known about the main mechanisms that underpin the interaction between these ice masses and climate. Furthermore, the nature of large-scale climatic control over the surface mass variations of the Patagonian Icefields still remains unclear. The main aim of this study is to understand the present-day climatic control of the surface mass balance (SMB) of the Patagonian Icefields at interannual timescales, especially considering large-scale processes. We modeled the present-day (1980-2015) glacioclimatic surface conditions for the southern Andes Cordillera by statistically downscaling the output from a regional climate model (RegCMv4) from a 10km spatial resolution to a 450m resolution grid and then using the downscaled fields as input for a simplified SMB model. Series of spatially averaged modeled fields over the Patagonian Icefields were used to derive regression and correlation maps against fields of climate variables from the ERA-Interim reanalysis. Years of relatively high SMB are associated with the establishment of an anomalous low-pressure center near the Drake Passage, the Drake low, that induces an anomalous cyclonic circulation accompanied with enhanced westerlies impinging on the Patagonian Icefields, which in turn leads to increases in the precipitation and the accumulation over the icefields. Also, the Drake low is thermodynamically maintained by a core of cold air that tends to reduce the ablation. Years of relatively low SMB are associated with the opposite conditions. We found low dependence of the SMB on main atmospheric modes of variability (El Niño-Southern Oscillation, Southern Annular Mode), revealing a poor ability of the associated indices to reproduce the interannual variability of the SMB. Instead, this study highlights the Drake Passage as a key region that has the potential to influence the SMB variability of the Patagonian Icefields. © 2023 The Author(s). | |
| Seasonal and Spatially Distributed Viral Metagenomes from Comau Fjord (42°S), Patagonia | Microbiology Resource Announcements | Castro-Nallar, E.; Berríos-Farías, V.; Díez, B.; Guajardo-Leiva, S. | 2023 | Zonas Costeras | 10.1128/mra.00082-23 | https://doi.org/10.1128/mra.00082-23 | 1-5 | Vol: 12 Issue: 4 | 2576-098X | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | Viruses are key players in marine environments, affecting food webs and biogeochemical cycles. We present 48 viral metagenomes and 5,656 viral operational taxonomic units (vOTUs) from Comau Fjord, Patagonia (42°S), to understand viral-mediated processes in coastal and estuarine waters. These data represent a spatial (35-km transect, two depths) and seasonal (winter and fall) data set. Copyright © 2023 Castro-Nallar et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license. |
| Spatially and Temporally Explicit Metagenomes and Metagenome-Assembled Genomes from the Comau Fjord (42°S), Patagonia | Microbiology Resource Announcements | Castro-Nallar, E.; Berríos-Farías, V.; Díez, B.; Guajardo-Leiva, S. | 2023 | Zonas Costeras | 10.1128/mra.00059-23 | https://doi.org/10.1128/mra.00059-23 | 1-3 | Vol: 12 Issue: 6 | 2576098X | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | Microbes play an important role in coastal and estuarine waters. We present 93 metagenomes and 677 metagenome-assembled genomes (MAGs) from Comau Fjord, Patagonia (42°S), to further understand the microbial dynamics and their response to anthropogenic disturbances. These data represent a spatially (35-km transect) and temporally (2016 to 2019) explicit data set. © 2023 Castro-Nallar et al. |
| Andean peatlands at risk? Spatiotemporal patterns of extreme NDVI anomalies, water extraction and drought severity in a large-scale mining area of Atacama, northern Chile | International Journal of Applied Earth Observation and Geoinformation | Chávez, R.; Meseguer-Ruiz, O.; Olea, M.; Calderón-Seguel, M.; Yager, K.; Isela Meneses, R.; Lastra, J.; Núñez-Hidalgo, I.; Sarricolea, P.; Serrano-Notivoli, R.; Prieto, M. | 2023 | Ciudades Resilientes | 10.1016/j.jag.2022.103138 | https://www.sciencedirect.com/science/article/pii/S1569843222003260 | 103138 | Vol: 116 | 15698432 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In the Andes, multiple human and climatic factors threaten the conservation of bofedales, a type of high altitude peat forming wetland widely distributed in the tropical and subtropical Andes. In northern Chile, climate change and water extraction for industrial activities are among the most significant threats to these relevant socio-hydrological systems hosting indigenous pastoral communities. In this study, we present an integrated analysis of Normalized Difference Vegetation Index (NDVI) anomalies, drought severity and water rights granted to industry to provide insight on the conservation status of bofedales, historical drivers of their transformation, and current threats. Using Landsat satellite imagery from 1986 to 2018, we identify spatio-temporal NDVI changes of 442 bofedales in one of the leading copper producing regions of the world. The NDVI time series analysis over 32 growing seasons was used to detect extreme anomalies, i.e. values outside the 95 % of the reference frequency distribution, indicating periods of extreme changes in the productivity of these high Andes wetlands. To evaluate the relationship between bofedales NDVI extreme periods to drought and continued water extraction activities, we combine a climate-based multi-temporal-scale drought index (SPEI) with the geospatial latitudinal distribution of water rights granted for extractive industries in the study area. Over the time period of analysis, the total amount of granted water rights increased 465 % from 1,201 l/s recorded before 1985 to 5,584 l/s in 2018. In the areas where the highest amount of water rights are concentrated, i.e. between 21.3°S and 22.1°S, “green” bofedales (NDVI>=0.23) are practically absent. NDVI of the austral summer (JFM) was highly correlated with the severity of drought occurring during the three months of the growing season peak. While our findings show bofedal productivity is mostly influenced by precipitation and temperature of the wet season (JFM) during the study period, results also raise questions regarding possible bofedal loss occurring over the previous 80 years prior to the satellite record, wherein water extraction activities have significantly increased according to official records. © 2022 |
| Antarctica and the Southern Ocean | Bulletin of the American Meteorological Society | Clem, K.; Adusumilli, S.; Baiman, R.; Banwell, A.; Barreira, S.; Beadling, R.; Bozkurt, D.; Colwell, S.; Coy, L.; Datta, R.; De Laat, J.; Du Plessis, M.; Dunmire, D.; Fogt, R.; Freeman, N.; Fricker, H.; Gardner, A.; Gille, S.; Johnson, B.; Josey, S.; Keller, L.; Kramarova, N.; Lazzara, M.; Lieser, J... | 2023 | Zonas Costeras | 10.1175/BAMS-D-23-0077.1 | https://journals.ametsoc.org/view/journals/bams/104/9/BAMS-D-23-0077.1.xml | S322-S365 | Vol: 104 Issue: 9 | 0003-0007, 1520-0477 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | |
| Assessment of the RegCM4-CORDEX-CORE performance in simulating cyclones affecting the western coast of South America | Climate Dynamics | Crespo, N.; Reboita, M.; Gozzo, L.; de Jesus, E.; Torres-Alavez, J.; Lagos-Zúñiga, M.; Torrez-Rodriguez, L.; Reale, M.; da Rocha, R. | 2023 | Zonas Costeras | 10.1007/s00382-022-06419-6 | https://doi.org/10.1007/s00382-022-06419-6 | 2041-2059 | Vol: 60 Issue: 7-8 | 0930-7575 | Thomson Reuters ISI (SCIE) | English | In this study, we assess the performance of the Regional Climate Model version 4 (RegCM4) in simulating the climatology of the cyclones near the west coast of South America. The synoptic evolution and seasonality of these systems are thoroughly investigated. The analyses are based on four simulations from the CORDEX-CORE Southern America (SA) domain, at 0.25° of horizontal resolution: one driven by ERA-Interim and three driven by different GCMs. The reference dataset is represented by ERA5. Cyclones were detected by an objective scheme in the period 1995–2005 and classified in three different classes: (i) Coastal Lows (CLs) and cyclones affecting the coast (CAC) (ii) crossing and (iii) not crossing the Andes. In general, RegCM4 is able to reproduce the climatology of cyclones affecting the western coast of SA. In particular: (i) CLs are shown to be more frequent in austral summer although their frequency is underestimated by the simulations in this season; (ii) CAC not crossing the Andes represent 76% of all CAC and are more frequent in winter, with simulation underestimating their frequency by ~ 22% due to the differences in the simulated upper-level jets, which tend to get weaker (by ~ 5–10 m s− 1) northwards of 30°S; (iii) the frequency of CAC crossing the Andes tends to be overestimated mainly in winter, which is associated with the combination of the stronger upper-level jets and weaker SLP in the simulations, especially southwards of 40°S. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. | |
| A regularization method based on level-sets for the problem of crack detection from electrical measurements | Inverse Problems | De Cezaro, A.; Hafemann, E.; Leitão, A.; Osses, A. | 2023 | Ciudades Resilientes | 10.1088/1361-6420/acb681 | https://doi.org/10.1088/1361-6420/acb681 | art: 035009 | Vol: 39 Issue: 3 | 0266-5611 | Thomson Reuters ISI (SCIE) | English | We investigate regularization methods for solving the problem of crack detection in bounded planar domains from electrical measurements on the boundary. Based on the multiple level-set approach introduced in Álvarez et al (2009 J. Comput. Phys. 228 5710-21) and on the regularization strategy devised in De Cezaro et al (2009 Inverse Problems 25 035004), we propose a Tikhonov type method for stabilizing the inverse problem. Convergence and stability results for this Tikhonov method are proven. An iterative method of (multiple) level-set type is derived from the optimality conditions for the Tikhonov functional, and a relation between this method and the iterated Tikhonov method is established. The proposed level-set method is tested on the same benchmark problem considered in Álvarez et al (2009 J. Comput. Phys. 228 5710-21). The numerical experiments demonstrate its ability to identify cracks in different scenarios with high accuracy even in the presence of noise. © 2023 IOP Publishing Ltd. | |
| The intensification of coastal hypoxia off central Chile: Long term and high frequency variability | Frontiers in Earth Science | De La Maza, L.; Farías, L. | 2023 | Zonas Costeras | 10.3389/feart.2022.929271 | https://www.frontiersin.org/articles/10.3389/feart.2022.929271/full | 929271 | Vol: 10 | 2296-6463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Hypoxia is a phenomenon where dissolved oxygen (DO) is reduced to levels that are low enough to strongly affect ecological and biogeochemical processes. This occurs within the continental shelf off central Chile (36°S), influenced by seasonal coastal upwelling (Spring-Summer). Monthly measurements of DO and other oceanographic variables in the water column (1997−2021) over the 92 m isobath along with high-resolution and near-surface observations (POSAR buoy), are analyzed to examine incidences of hypoxia and understand the physical and biogeochemical processes modulating DO vertical distribution and its temporal variability. On average, the percentage of the water column with DO levels below 89 (hypoxia) and 22 (severe hypoxia) μmol L −1 reaches 68% (i.e., hypoxic waters are found below 30 m) and 44% (below 50 m depth), respectively, but during the upwelling season, as much as 87% (below 12 m depth) and 81% (below 17 m depth) of the water column exhibits these levels. On the sub-seasonal scale during upwelling season six hypoxic events lasting at least 2 days occur at 10 m depth. There is a strong seasonal correlation between the volume of the seawater presenting hypoxia and upwelling favorable winds. Furthermore, there is a high DO interannual variability partially related to the El Niño Southern Oscillation (ENSO). Over 2 decades, it is estimated that DO concentration in surface and subsurface layers decreases (up to 21 μmol L −1 decade −1 ) as waters get colder (up to 0.29°C decade −1 ). Remarkably, the volume of hypoxic and severe hypoxic waters over the shelf has increased more than 2 times since 1997 and shows a significant positive correlation with the upwelling index. These preliminary findings indicate that the increase in local DO consumption is partially associated with upwelling intensification. Given the clear evidence of wind intensification in coastal upwelling ecosystems and thus the increase in hypoxic events, the coastal zone may be highly vulnerable to hypoxia, impacting biological resources and biogeochemical cycles. |
| A machine learning approach to address air quality changes during the COVID-19 lockdown in Buenos Aires, Argentina | Earth System Science Data | Diaz Resquin, M.; Lichtig, P.; Alessandrello, D.; De Oto, M.; Gómez, D.; Rössler, C.; Castesana, P.; Dawidowski, L. | 2023 | Ciudades Resilientes | 10.5194/essd-15-189-2023 | https://doi.org/10.5194/essd-15-189-2023 | 189-209 | Vol: 15 Issue: 1 | 1866-3508 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Having a prediction model for air quality at a low computational cost can be useful for research, forecasting, regulatory, and monitoring applications. This is of particular importance for Latin America, where rapid urbanization has imposed increasing stress on the air quality of almost all cities. In recent years, machine learning techniques have been increasingly accepted as a useful tool for air quality forecasting. Out of these, random forest has proven to be an approach that is both well-performing and computationally efficient while still providing key components reflecting the nonlinear relationships among emissions, chemical reactions, and meteorological effects. In this work, we employed the random forest methodology to build and test a forecasting model for the city of Buenos Aires. We used this model to study the deep decline in most pollutants during the lockdown imposed by the COVID-19 (COronaVIrus Disease 2019) pandemic by analyzing the effects of the change in emissions, while taking into account the changes in the meteorology, using two different approaches. First, we built random forest models trained with the data from before the beginning of the lockdown periods. We used the data to make predictions of the business-as-usual scenario during the lockdown periods and estimated the changes in concentrations by comparing the model results with the observations. This allowed us to assess the combined effects of the particular weather conditions and the reduction in emissions during the period when restrictions were in place. Second, we used random forest with meteorological normalization to compare the observational data from the lockdown periods with the data from the same dates in 2019, thus decoupling the effects of the meteorology from short-term emission changes. This allowed us to analyze the general effect that restrictions similar to those imposed during the pandemic could have on pollutant concentrations, and this information could be useful to design mitigation strategies. The results during testing showed that the model captured the observed hourly variations and the diurnal cycles of these pollutants with a normalized mean bias of less than 6% and Pearson correlation coefficients of the diurnal variations between 0.64 and 0.91 for all the pollutants considered. Based on the random forest results, we estimated that the lockdown implied relative changes in concentration of up to -45% for CO, -75% for NO, -46% for NO2, -12% for SO2, and -33% for PM10 during the strictest mobility restrictions. O3 had a positive relative change in concentration (up to an 80%) that is consistent with the response in a volatile-organic-compound-limited chemical regime to the decline in NOx emissions. The relative changes estimated using the meteorological normalization technique show mostly smaller changes than those obtained by the random forest predictive model. The relative changes were up to -26% for CO, up to -47% for NO, -36% for NO2, -20% for PM10, and up to 27% for O3. SO2 is the only species that had a larger relative change when the meteorology was normalized (up to 20%). This points out the need for accounting not only for differences in emissions but also in meteorological variables in order to evaluate the lockdown effects on air quality. The findings of this study may be valuable for formulating emission control strategies that do not disregard their implication on secondary pollutants. We believe that the model itself can also be a valuable contribution to a forecasting system in the city and that the general methodology could also be easily applied to other Latin American cities as well. We also provide the first O3 and SO2 observational dataset in more that a decade for a residential area in Buenos Aires, and it is openly available at 10.17632/h9y4hb8sf8.1 . © 2023 Melisa Diaz Resquin et al. |
| CLSoilMaps: A national soil gridded database of physical and hydraulic soil properties for Chile | Scientific Data | Dinamarca, D.; Galleguillos, M.; Seguel, O.; Faúndez Urbina, C. | 2023 | Cambio de Uso de Suelo | 10.1038/s41597-023-02536-x | https://doi.org/10.1038/s41597-023-02536-x | art630 | Vol: 10 Issue: 1 | 20524463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Spatially explicit soil information is crucial for comprehending and managing many of Earth´s processes related to carbon, water, and other biogeochemical cycles. We introduced a gridded database of soil physical properties and hydraulic parameters at 100 meters spatial resolution. It covers the continental area of Chile and binational basins shared with Argentina for six standardized depths following the specifications of the GlobalSoilMap project. We generated soil maps based on digital soil mapping techniques based on more than 4000 observations, including unpublished data from remote areas. These maps were used as input for the pedotransfer function Rosetta V3 to obtain predictions of soil hydraulic properties, such as field capacity, permanent wilting point, total available water capacity, and other parameters of the water retention curve. The trained models outperformed several other DSM studies applied at the national and regional scale for soil physical properties (nRMSE ranging from 6.93% to 15.7%) and delivered acceptable predictions (nRMSE ranging from 10.4% to 15.6%) for soil hydraulic properties, making them suitable for countless environmental studies. © 2023, Springer Nature Limited. |
| Assessing the conditions of Rationality and Plausibility in the valuation of biodiversity conservation in a mega-biodiverse country. The case of Manu in Perú; [Evaluando las condiciones de racionalidad y plausibilidad en la valoración de conservar la biodiversidad de un país megabiodiverso El caso del Manu en Perú] | Economia Agraria y Recursos Naturales | Dávila, J.; Vásquez-Lavín, F.; Orihuela, C.; Oliva, R.; Lavado-Solis, K.; Paredes-Vilca, O.; Ñañez, R.; Díaz, S. | 2023 | Cambio de Uso de Suelo | 10.7201/earn.2023.01.02 | https://doi.org/10.7201/earn.2023.01.02 | 35-54 | Vol: 23 Issue: 1 | 15780732 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | According to NOAA, the results of an economic valuation are applicable as public policy if they fulfill two conditions: rationality and plausibility. In this study, we carried out the valuation of biodiversity conservation in Manu National Park in Peru (a megabiodiverse country), based on three representations: species, habitat and functionality. We identify sensitivity to scope in most of the attributes used. When we add socioeconomic characteristics, we identify that gender and salary levels affect preferences. Our total analysis shows that number of threatened plant species and functionality better fulfill both conditions. © (2023), All Rights Reserved. |
| Freshwater diatom evidence for Southern Westerly Wind evolution since ∼18 ka in northwestern Patagonia | Quaternary Science Reviews | Díaz, C.; Moreno, P.; Villacís, L.; Sepúlveda-Zúñiga, E.; Maidana, N. | 2023 | Agua y Extremos | 10.1016/j.quascirev.2023.108231 | https://doi.org/10.1016/j.quascirev.2023.108231 | art108231 | Vol: 316 | 02773791 | Thomson Reuters ISI (SCIE) | English | We report a fossil diatom record from small closed-basin Lago Lepué (43°S) to examine past changes in freshwater ecosystems and hydrologic balance in northwestern Patagonia since ∼18 ka. The record starts with abundant staurosiroids and the heavily silicified Aulacoseira granulata suggesting deep turbulent mixing during a low lake level stand between ∼18- 16.4 ka. A. distans increased shortly after ∼16.4 ka and achieved maximum abundance between ∼15.4-13.6 ka, while A. granulata disappeared at ∼15.8 ka and A. alpigena rose at ∼14.9 ka to its maximum between ∼13-12 ka. We infer turbulent, cold, and circumneutral to slightly acid lake conditions contemporaneous with a steady lake level rise that started at ∼16.4 ka and culminated between ∼13-12 ka. These trends reversed between ∼11-7.8 ka with the dominance of Discostella stelligera and staurosiroids, suggesting warmer lake conditions and shallower mixing. Subsequent changes include increases of A. distans with D. stelligera between ∼7.8-5.8 ka, dominance of the former between ∼5.8-3.3 ka, a rapid increase in A. perglabra at ∼3.3 ka, and ensuing diversification of benthic acidophilous species. We infer a rapid lake-level decline between ∼11-7.8 ka, with subsequent rising pulses at ∼7.8 ka and ∼5.8 ka, a multimillennial-scale lake acidification trend, and overall high lake levels with centennial-scale reversals between ∼6-0 ka. Coherent variations in terrestrial and aquatic ecosystem changes recorded in the same core suggest negative hydrologic balance between ∼18-16.4 ka and ∼11–7.8 ka, positive balance between ∼14.9-12 ka and ∼6–0 ka, with transitional conditions in the interim, overprinted by millennial-scale changes and enhanced variability since ∼6 ka. Covariation with paleoclimate records at regional, pan-Patagonian, and hemispheric scale suggests millennial to centennial-scale variability superimposed upon a multi-millennial pacing of Southern Westerly Wind evolution since ∼18 ka. © 2023 Elsevier Ltd | |
| The impact of local and climate change drivers on the formation, dynamics, and potential recurrence of a massive fish-killing microalgal bloom in Patagonian fjord | Science of The Total Environment | Díaz, P.; Pérez-Santos, I.; Basti, L.; Garreaud, R.; Pinilla, E.; Barrera, F.; Tello, A.; Schwerter, C.; Arenas-Uribe, S.; Soto-Riquelme, C.; Navarro, P.; Díaz, M.; Álvarez, G.; Linford, P.; Altamirano, R.; Mancilla-Gutiérrez, G.; Rodríguez-Villegas, C.; Figueroa, R. | 2023 | Agua y Extremos; Zonas Costeras | 10.1016/j.scitotenv.2022.161288 | https://linkinghub.elsevier.com/retrieve/pii/S0048969722083929 | 161288 | Vol: 865 | 00489697 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Harmful algal blooms (HABs) in southern Chile are a serious threat to public health, tourism, artisanal fisheries, and aquaculture in this region. Ichthyotoxic HAB species have recently become a major annual threat to the Chilean salmon farming industry, due to their severe economic impacts. In early austral autumn 2021, an intense bloom of the raphidophyte Heterosigma akashiwo was detected in Comau Fjord, Chilean Patagonia, resulting in a high mortality of farmed salmon (nearly 6000 tons of biomass) within 15 days. H. akashiwo cells were first detected at the head of the fjord on March 16, 2021 (up to 478 cells mL−1). On March 31, the cell density at the surface had reached a maximum of 2 × 105 cells mL−1, with intense brown spots visible on the water surface. Strong and persistent high-pressure anomalies over the southern tip of South America, consistent with the positive phase of the Southern Annular Mode (SAM), resulted in extremely dry conditions, high solar radiation, and strong southerly winds. A coupling of these features with the high water retention times inside the fjord can explain the spatial-temporal dynamics of this bloom event. Other factors, such as the internal local physical uplift process (favored by the north-to-south orientation of the fjord), salt-fingering events, and the uplift of subantarctic deep-water renewal, likely resulted in the injection of nutrients into the euphotic layer, which in turn could have promoted cell growth and thus high microalgal cell densities, such as reached by the bloom. © 2022 Elsevier B.V. |
| From lipophilic to hydrophilic toxin producers: Phytoplankton succession driven by an atmospheric river in western Patagonia | Marine Pollution Bulletin | Díaz, P.; Álvarez, G.; Figueroa, R.; Garreaud, R.; Pérez-Santos, I.; Schwerter, C.; Díaz, M.; López, L.; Pinto-Torres, M.; Krock, B. | 2023 | Agua y Extremos | 10.1016/j.marpolbul.2023.115214 | https://doi.org/10.1016/j.marpolbul.2023.115214 | art: 115214 | Vol: 193 | 0025-326X | Thomson Reuters ISI (SCIE) | English | Phytoplankton succession is related to hydroclimatic conditions. In this study we provide the first description of a toxic phytoplankton succession in the Patagonian Fjord System. The shift was modulated by atmospheric-oceanographic forcing and consisted of the replacement of the marine dinoflagellate Dinophysis acuta in a highly stratified water column during austral summer by the diatom Pseudo-nitzschia calliantha in a mixed water column during late summer and early autumn. This transition, accompanied by a change in the biotoxin profiles (from lipophilic dinophysis toxins to hydrophilic domoic acid), was induced by the arrival of an intense atmospheric river. The winds in Magdalena Sound may have been further amplified, due to its west-east orientation and its location within a tall, narrow mountain canyon. This work also documents the first known appearance of toxic P. calliantha in Northern Patagonian. The potential impacts of the biotoxins of this species on higher trophic levels are discussed. © 2023 Elsevier Ltd | |
| Estimating soil water content in a thorny forest ecosystem by time-lapse electrical resistivity tomography (ERT) and HYDRUS 2D/3D simulations | Hydrological Processes | Faúndez Urbina, C.; Alanís, D.; Ramírez, E.; Seguel, O.; Fustos, I.; Donoso, P.; de Miranda, J.; Rakonjac, N.; Palma, S.; Galleguillos, M. | 2023 | Cambio de Uso de Suelo | 10.1002/hyp.15002 | https://doi.org/10.1002/hyp.15002 | arte15002 | Vol: 37 Issue: 10 | 08856087 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Determination of soil volumetric water content (Figure presented.) in forest ecosystems is particularly challenging due to deep rooting systems and unknown soil vertical and spatial heterogeneity. This research aims to test two undisturbed methods, electrical resistivity tomography (ERT) and HYDRUS 2D/3D, for 2D (Figure presented.) determination in a thorny forest ecosystem. The experiment consisted of infiltrating 10 L of water lasting 60 min. During infiltration, ERT measured apparent resistivity by time-lapse measurements, and (Figure presented.) was measured with an FDR probe (EnviroSCAN) at 33, 63, 83, 97, and 163 cm depth close to the infiltration site. At the end of infiltration, a soil pit was dug, and 100 measurements of (Figure presented.) were performed with a TDR in a 10 × 10 cm regular grid. Archie law transformed soil resistivity (ERT) into (Figure presented.) using manual calibration, verified by an independent dataset. The 2D (Figure presented.) profile obtained by ERT was qualitatively compared with the HYDRUS 2D/3D one. HYDRUS 2D/3D was parametrized with calibrated parameters obtained with HYDRUS 1D using 106 days of (Figure presented.) obtained with EnviroSCAN. The results of HYDRUS 1D calibration and verification were satisfactory, with RMSE and Nash-Sutcliffe coefficients ranging from 0.021 to 0.034 cm3 cm−3 and 0.11 to 0.77, respectively. The forward HYDRUS 2D/3D (Figure presented.) simulation disagrees with EnviroSCAN data for 33 cm depth. However, it follows the trend with near to zero variation of water content at 63 cm depth. Water content determination by ERT was satisfactory with RMSE for calibration and verification of 0.017 and 0.021 cm3 cm−3. HYDRUS 2D/3D and ERT comparisons were not equal, with a shallower wetting front by ERT and a deeper one for HYDRUS. Still, both wetting fronts agree with the wetting depth estimated by EnviroSCAN. We conclude that both methods are an alternative for (Figure presented.) determination in heterogeneous and deep soils of forest ecosystems. © 2023 John Wiley & Sons Ltd. |
| The economics impacts of long-run droughts: Challenges, gaps, and way forward | Journal of Environmental Management | Fernández, F.; Vásquez-Lavín, F.; Ponce, R.; Garreaud, R.; Hernández, F.; Link, O.; Zambrano, F.; Hanemann, M. | 2023 | Agua y Extremos; Cambio de Uso de Suelo | 10.1016/j.jenvman.2023.118726 | https://doi.org/10.1016/j.jenvman.2023.118726 | art118726 | Vol: 344 | 03014797 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Quantifying drought's economic impacts has been key for decision-making to build future strategies and improve the development and implementation of proactive plans. However, climate change is changing drought frequency, intensity, and durability. These changes imply modifications of their economic impact, as longer droughts result in greater cumulative economic losses for water users. Though the longer the drought lasts, other factors also play a crucial role in its economic outcomes, such as Infrastructure capacity (IC), the Amount of Water in Storage (AWS) in reservoirs and aquifers, and short- and long-term responses to it. This study proposes and applies an analytical framework for the economic assessment of long-run droughts, assessing and explaining central Chile megadrought economic effects through the factors that begin to influence the economic impact level in this setting. High levels of both IC and the AWS, as well as short- and long-term responses of water users, allow for high resilience to long-run droughts, tolerating extraordinary water disruption in its society with relatively low total economic impacts. Despite this adaptability, long-term droughts bring places to a water-critical threshold where long-term adaptation strategies may be less flexible than short-term strategies, escalating the adverse economic effects. This fact suggests that the economic evaluation of megadrought needs to focus on future tipping points (substantial water scarcity). The tipping point depends on the IC, how water users manage the AWS, and adaptation strategies. Establishing the tipping point should be a priority for future interdisciplinary research. © 2023 |
| Chilean long-term Socio-Ecological Research Network: progresses and challenges towards improving stewardship of unique ecosystems: Red Chilena de Investigación Socio-Ecológica de Largo Plazo: Avances y desafíos para el manejo responsable de ecosistemas únicos | Revista Chilena de Historia Natural | Frêne, C.; Armesto, J.; Nespolo, R.; Gaxiola, A.; Navarrete, S.; Troncoso, A.; Muñoz, A.; Corcuera, L. | 2023 | Agua y Extremos | 10.1186/s40693-023-00114-4 | https://doi.org/10.1186/s40693-023-00114-4 | art: 1 | Vol: 96 Issue: 1 | 0716-078X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Ecosystems provide a variety of benefits to human society and humanity’s utilization of ecosystems affects their composition, structure, and functions. Global change drivers demand us to study the interactions between ecological and social systems, and advise strategies to protect the large fraction of Chilean unique ecosystems. Long-term research and monitoring are vital for meaningful understanding of human impacts and socio-ecological feedback, which occur over multiple spatial and time-scales and can be invisible to traditional grant-sponsored short-term studies. Despite the large fraction of unique ecosystems, Chilean government agencies have not established long-term monitoring programs to inform and guide management decisions for use, conservation, and adaptation to climate change. Responding to this void, the Chilean Long-Term Socio-Ecological Research Network (LTSER-Chile) was created, comprising nine study sites funded by a variety of private and public institutions, that broadly seeks to understand how global change is altering biodiversity and ecosystem functions. The LTSER-Chile is currently in a phase of institutional consolidation to achieve its objectives of alignment with international efforts, fill the need for high-quality, long-term data on social, biological and physical components of Chilean ecosystems, and develop itself as an open research platform for the world. Despite the wide diversity of ecosystems ecncompased by LTSER-Chile sites, several common variables are monitored, especially climatic and hydrographic variables and many ecological indicator variables that consider temporal fluctuations, population and community dynamics. The main challenges currently facing the LTSER-Chile are to secure funding to maintain existing long-term monitoring programs, to persuade public and private decision-makers about its central role in informing and anticipating socio-ecological problems, and to achieve greater ecosystem representation by integrating new long-term study sites. This will require a more decisive political commitment of the State, to improve the stewardship of our unique terrestrial and marine ecosystems, and the realization that sound ecologically-sustainable policies will never be possible without a national monitoring network. We argue that the State should build on LTSER and several other private and university initiatives to provide the country with a monitoring network. In the absence of this commitment, the LTSER system is subject to discontinuity and frequent interruptions, which jeopardizes the long-term effort to understand the functioning of nature and its biodiversity. © 2023, The Author(s). |
| Memoria institucional 10 años CR2: 201 | Garreaud, R. | 2023 | https://www.cr2.cl/memoria2013-2022/ | 50 | cr2.cl | ||||||||
| Cooling the Coldest Continent The 4 December 2021 Total Solar Eclipse over Antarctica | Bulletin of the American Meteorological Society | Garreaud, R.; Bozkurt, D.; Spangrude, C.; Carrasco-Escaff, T.; Rondanelli, R.; Muñoz, R.; Jubier, X.; Lazzara, M.; Keller, L.; Rojo, P. | 2023 | Agua y Extremos; Zonas Costeras | 10.1175/BAMS-D-22-0272.1 | https://doi.org/10.1175/BAMS-D-22-0272.1 | E2265-E2285 | Vol: 104 Issue: 12 | 00030007 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Total solar eclipses (TSEs) are impressive astronomical events that have attracted people’s curiosity since ancient times. Their abrupt alterations to the radiation balance have stimulated studies on “eclipse meteorology,” most of them documenting events in the Northern Hemisphere while only one TSE (23 November 2003) has been described over Antarctica. On 4 December 2021—just a few days before the austral summer solstice—the moon blocked the sun over the austral high latitudes, with the path of totality arching from the Weddell Sea to the Amundsen Sea, thus producing a ∼2-min central TSE. In this work we present high-resolution meteorological observations from Union Glacier Camp (80°S, 83°W), the only location with a working station under totality, and South Pole station. These observations were complemented with meteorological records from 37 surface stations across Antarctica. Notably, the largest cooling (∼5°C) was observed over the East Antarctic dome, where obscurity was ∼85% while many sectors experienced insignificant temperature changes. This heterogenous cooling distribution, at odds with the seemingly homogeneous land surface of Antarctica, is partially captured by a simple radiative model. To further diagnose the effect of the eclipse on the surface meteorology, we ran multiple pairs of simulations (eclipse enabled and disabled) using the Weather Research and Forecasting (WRF) Model. The overall pattern and magnitude of the simulated cooling agree well with the observations and reveal that, in addition to the solar radiation deficit and cloud cover, low-level winds and the height of the planetary boundary layer are key determinants of the temperature changes and their spatial variability. © 2023 American Meteorological Society. This published article is licensed under the terms of the default AMS reuse license. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses). |
| Evolution of heatwaves in Chile since 1980 | Weather and Climate Extremes | González-Reyes, Á.; Jacques-Coper, M.; Bravo, C.; Rojas, M.; Garreaud, R. | 2023 | Agua y Extremos; Zonas Costeras | 10.1016/j.wace.2023.100588 | https://doi.org/10.1016/j.wace.2023.100588 | art100588 | Vol: 41 | 22120947 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Heatwaves (HWs) are highly dangerous threats to human and ecosystem health, as well as to many economic sectors around the world. In the present work focused on Chile, we use a high-resolution (∼5 km) gridded product (CR2Met v2.0) to evaluate the spatiotemporal distribution and trends of HWs. We analyze daily maximum temperatures (Tx) from late austral spring to early autumn (November to March) to evaluate the HWs behavior during 1980–2020, using three criteria: i) three consecutive days with Tx > 30°C, ii) three consecutive days with Tx > 90th percentile (P90), and iii) three consecutive days with Tx > 95th percentile (P95). We validated our results using HWs statistics based on eighteen official meteorological stations; this procedure revealed a coherence with gridded data mainly over the Central Valley and the Andes. Using the P90 threshold, we found upward trends across the Andes between 20° and 36°S (>1 events per decade), and in the Central Valley between 34° - 43°S (>0.75 events per decade). In addition, using the P90 and P95 thresholds, HWs exhibit upward trends (>1 and 0.5 events per decade, respectively) throughout most of Chile, including Andes and Patagonia. Moreover, using all thresholds, we found an increase in HW frequency during the 2011–2020 megadrought period (ranging from 1 to 4 HWs events/decade) in comparison to the previous period (1980–2010). Meteorological factors such as an increase in the frequency of Puelche (Föhn-like) winds are proposed as an amplifying mechanism of HWs in South-Central Chile. © 2023 |
| A First Insight into the Microbial and Viral Communities of Comau Fjord—A Unique Human-Impacted Ecosystem in Patagonia (42° S) | Microorganisms | Guajardo-Leiva, S.; Mendez, K.; Meneses, C.; Díez, B.; Castro-Nallar, E. | 2023 | Zonas Costeras | 10.3390/microorganisms11040904 | https://doi.org/10.3390/microorganisms11040904 | art: 904 | Vol: 11 Issue: 4 | 2076-2607 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | While progress has been made in surveying the oceans to understand microbial and viral communities, the coastal ocean and, specifically, estuarine waters, where the effects of anthropogenic activity are greatest, remain partially understudied. The coastal waters of Northern Patagonia are of interest since this region experiences high-density salmon farming as well as other disturbances such as maritime transport of humans and cargo. Here, we hypothesized that viral and microbial communities from the Comau Fjord would be distinct from those collected in global surveys yet would have the distinctive features of microbes from coastal and temperate regions. We further hypothesized that microbial communities will be functionally enriched in antibiotic resistance genes (ARGs) in general and in those related to salmon farming in particular. Here, the analysis of metagenomes and viromes obtained for three surface water sites showed that the structure of the microbial communities was distinct in comparison to global surveys such as the Tara Ocean, though their composition converges with that of cosmopolitan marine microbes belonging to Proteobacteria, Bacteroidetes, and Actinobacteria. Similarly, viral communities were also divergent in structure and composition but matched known viral members from North America and the southern oceans. Microbial communities were functionally enriched in ARGs dominated by beta-lactams and tetracyclines, bacitracin, and the group macrolide–lincosamide–streptogramin (MLS) but were not different from other communities from the South Atlantic, South Pacific, and Southern Oceans. Similarly, viral communities were characterized by exhibiting protein clusters similar to those described globally (Tara Oceans Virome); however, Comau Fjord viromes displayed up to 50% uniqueness in their protein content. Altogether, our results indicate that microbial and viral communities from the Comau Fjord are a reservoir of untapped diversity and that, given the increasing anthropogenic impacts in the region, they warrant further study, specifically regarding resilience and resistance against antimicrobials and hydrocarbons. © 2023 by the authors. |
| Earth system justice needed to identify and live within Earth system boundaries | Nature Sustainability | Gupta, J.; Liverman, D.; Prodani, K.; Aldunce, P.; Bai, X.; Broadgate, W.; Ciobanu, D.; Gifford, L.; Gordon, C.; Hurlbert, M.; Inoue, C.; Jacobson, L.; Kanie, N.; Lade, S.; Lenton, T.; Obura, D.; Okereke, C.; Otto, I.; Pereira, L.; Rockström, J.; Scholtens, J.; Rocha, J.; Stewart-Koster, B.; David T... | 2023 | Agua y Extremos | 10.1038/s41893-023-01064-1 | https://doi.org/10.1038/s41893-023-01064-1 | 630-638 | Vol: 6 | 2398-9629 | Thomson Reuters ISI (SCIE; SSCI) | English | Living within planetary limits requires attention to justice as biophysical boundaries are not inherently just. Through collaboration between natural and social scientists, the Earth Commission defines and operationalizes Earth system justice to ensure that boundaries reduce harm, increase well-being, and reflect substantive and procedural justice. Such stringent boundaries may also affect ‘just access’ to food, water, energy and infrastructure. We show how boundaries may need to be adjusted to reduce harm and increase access, and challenge inequality to ensure a safe and just future for people, other species and the planet. Earth system justice may enable living justly within boundaries. © 2023, Springer Nature Limited. | |
| Facilitation by pioneer trees and herbivore exclusion allow regeneration of woody species in the semiarid ecosystem of central Chile | Applied Vegetation Science | Gómez-Fernández, N.; Smith-Ramírez, C.; Delpiano, C.; Miranda, A.; Vásquez, I.; Becerra, P. | 2023 | Cambio de Uso de Suelo | 10.1111/avsc.12741 | https://doi.org/10.1111/avsc.12741 | arte12741 | Vol: 26 Issue: 3 | 14022001 | Thomson Reuters ISI (SCIE) | English | Questions: Facilitation by pioneer plants and herbivore exclusion may contribute to plant regeneration and restoration of degraded semiarid ecosystems. In this study we evaluated the main and interactive effects of the exclusion of large and medium-sized mammal herbivores and the presence of the pioneer tree Vachellia caven on natural regeneration of woody species in degraded savannas. Location: Two localities of the native sclerophyllous forest of central Chile. Methods: Twelve 30 × 40 m exclosures and twelve non-exclosure areas located near native forests were established in savannas of V. caven in each locality. Regeneration coming from seeds and resprouts was sampled both under the canopy of V. caven and without canopy in each exclosure and non-excluded area. Results: After seven years, species richness and density of older regeneration (0.5–2 m high) were positively affected by herbivore exclusion and the presence of V. caven. No significant interaction between herbivore exclusion and V. caven was observed. Younger regeneration (<0.5 m high) was positively affected by herbivore exclusion and the presence of V. caven only in some years with almost no interactive effect. Conclusions: The exclusion of large and medium-sized exotic herbivores and facilitation by pioneer trees are complementary for regeneration. The variable but permanent presence of younger and older regeneration within exclosures and under V. caven during the experiment may lead to an increase of density and diversity of adult plants and recovery of the native forest. However, this process may be slow due to other limiting factors, for instance, reduced precipitation associated with climate change. © 2023 International Association for Vegetation Science. | |
| Afforestation and climate mitigation: lessons from Chile | Trends in Ecology and Evolution | Gómez-González, S.; Miranda, A.; Hoyos-Santillan, J.; Lara, A.; Moraga, P.; Pausas, J. | 2023 | Cambio de Uso de Suelo; Gobernanza e Interfaz Ciencia y Política | 10.1016/j.tree.2023.09.014 | https://doi.org/10.1016/j.tree.2023.09.014 | 5-8 | Vol: 39 Issue: 1 | 01695347 | Thomson Reuters ISI (SCIE) | English | The Chilean Climate Change Law excludes tree monocultures as a solution to the climate crisis, offering an opportunity for resilience and climate mitigation in Latin America. The Chilean experience with mega-fires in extensive, homogeneous forest plantations provides important lessons that could inform climate policies in other countries. © 2023 Elsevier Ltd | |
| Forest landscape dynamics after intentional large-scale fires in western Patagonia reveal unusual temperate forest recovery trends | Landscape Ecology | Hernández-Moreno, Á.; Soto, D.; Miranda, A.; Holz, A.; Armenteras-Pascual, D. | 2023 | Cambio de Uso de Suelo | 10.1007/s10980-023-01687-x | https://doi.org/10.1007/s10980-023-01687-x | 2207-2225 | Vol: 38 Issue: 9 | 0921-2973 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Context: Western Chilean Patagonia is an isolated temperate region with an important proportion of intact forest landscapes (IFL) that was subjected to large-scale fires over 60 years ago. However, there is no empirical evaluation of the land cover dynamics to establish the forest loss and recovery, and the effect on the landscape structure and function, and remnant IFL following the fires. Objectives: The present study addressed the following questions: (1) What have been the main trends of the land cover dynamics between 1984 and 2018 following earlier fires, and how have these trends shaped the spatial patterns and potential carbon stock of forests in western Patagonia? (2) What proportion of forest landscape remains intact following fires in this region? Methods: We selected the Coyhaique Province (1,231,910 ha) in western Chilean Patagonia as the study area. Land cover maps for three dates (1984, 2000, 2018) were used to evaluate landscape dynamics after fires. A map of persistence and change occurrence was made to estimate the IFL area over the 1984–2018 period. Landscape metrics were used to assess landscape structure change, and potential carbon stock was estimated based on a literature review. Results: Following fires, the main land cover changes between 1984 and 2018 were loss of ~ 32,600 ha of old-growth forest and a recovery of ~ 69,000 ha of second-growth forest. The increase in second-growth forest area mainly resulted from loss of agricultural cover (~ 41% of the area). Despite these changes, ~ 61% of the area could potentially remain as IFL after fires. Over the 1984–2018 period, a slight increase in fragmentation of old-growth forest, and a decline in second-growth forest were observed. Coyhaique Province experienced a slight increase (3.6%) in overall potential carbon stock, likely as a result of second-growth forest recovery. Conclusions: Our study provides the first evidence of the western Patagonia landscape state after more than six decades since the large-scale fires. The results provide baseline information on landscape structure and function that could help to make conservation and forest management decisions on specific territory areas. © 2023, The Author(s), under exclusive licence to Springer Nature B.V. |
| Panama must protect mangroves and peatlands | Science (New York, N.Y.) | Hoyos-Santillan, J.; Miranda, A.; Castro de Doens, L.; González-Mahecha, E.; Cifuentes-Jara, M.; Worthington, T. | 2023 | Cambio de Uso de Suelo | 10.1126/science.adl3048 | https://doi.org/10.1126/science.adl3048 | 654 | Vol: 382 Issue: 6671 | 10959203 | Thomson Reuters ISI (SCIE) | English | ||
| Synoptic-to-intraseasonal atmospheric modulation of phytoplankton biomass in the inner sea of Chiloé, Northwest Patagonia (42.5°-43.5°S, 72.5°-74°W), Chile | Frontiers in Marine Science | Jacques-Coper, M.; Segura, C.; De La Torre, M.; Valdebenito Muñoz, P.; Vásquez, S.; Narváez, D. | 2023 | Zonas Costeras | 10.3389/fmars.2023.1160230 | https://doi.org/10.3389/fmars.2023.1160230 | 1160230 | Vol: 10 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Inner Sea of Chiloé (ISC) in northwestern Patagonia has experienced large harmful algal blooms in the past decade, impacting human health and affecting the large aquaculture industry of the region. Thus, the investigation of factors favouring regional phytoplankton growth are of particular interest. Analysing the synoptic-to-intraseasonal variability, we explore changes in phytoplankton biomass in southern ISC (S-ISC, 42.5°-43.5°S, 72.5°-74°W) and their concurrent mesoscale and large-scale meteorological and oceanographic conditions. We use high-resolution satellite normalized fluorescence line height (nFLH) and chlorophyll-a (CHL-A) from the MODIS-Aqua sensor as proxies for phytoplankton biomass, besides oceanic and atmospheric variables derived from various remote-sensing sources and atmospheric fields from the ERA5 reanalysis. Specifically, we focus on high phytoplankton biomass events HBEs, which are defined as those cases when intraseasonal nFLH anomaly (nFLH’) exceeds the 95th percentile threshold. Each event was characterised by its first date of occurrence (called day 0). We detected 16 HBE between 2003 and 2019 in S-ISC. HBEs tend to occur under the influence of a mid-latitude migratory anticyclone that induce persistent cloudless conditions preceding day 0, leading to enhanced photosynthetically active radiation (PAR) starting around day -8, and positive sea surface temperature (SST) anomalies between days -4 and +4. We hypothesise that HBEs are mainly modulated by i) mixing and advection that could contribute to a greater availability of nutrients in the upper sea layers before the onset of the anticyclonic anomalies; and ii) increased thermal stratification related to positive PAR and SST anomalies that would promote phytoplankton growth during the anticyclonic regime. Furthermore, we show that the Madden-Julian Oscillation modulates the frequency of nFLH’ and thus of HBEs, a result that suggests an enhanced predictability of these cases. |
| Distribution and Activity of Sulfur-Metabolizing Bacteria along the Temperature Gradient in Phototrophic Mats of the Chilean Hot Spring Porcelana | Microorganisms | Konrad, R.; Vergara-Barros, P.; Alcorta, J.; Alcamán-Arias, M.; Levicán, G.; Ridley, C.; Díez, B. | 2023 | Zonas Costeras | 10.3390/microorganisms11071803 | https://doi.org/10.3390/microorganisms11071803 | art1803 | Vol: 11 Issue: 7 | 2076-2607 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In terrestrial hot springs, some members of the microbial mat community utilize sulfur chemical species for reduction and oxidization metabolism. In this study, the diversity and activity of sulfur-metabolizing bacteria were evaluated along a temperature gradient (48–69 °C) in non-acidic phototrophic mats of the Porcelana hot spring (Northern Patagonia, Chile) using complementary meta-omic methodologies and specific amplification of the aprA (APS reductase) and soxB (thiosulfohydrolase) genes. Overall, the key players in sulfur metabolism varied mostly in abundance along the temperature gradient, which is relevant for evaluating the possible implications of microorganisms associated with sulfur cycling under the current global climate change scenario. Our results strongly suggest that sulfate reduction occurs throughout the whole temperature gradient, being supported by different taxa depending on temperature. Assimilative sulfate reduction is the most relevant pathway in terms of taxonomic abundance and activity, whereas the sulfur-oxidizing system (Sox) is likely to be more diverse at low rather than at high temperatures. Members of the phylum Chloroflexota showed higher sulfur cycle-related transcriptional activity at 66 °C, with a potential contribution to sulfate reduction and oxidation to thiosulfate. In contrast, at the lowest temperature (48 °C), Burkholderiales and Acetobacterales (both Pseudomonadota, also known as Proteobacteria) showed a higher contribution to dissimilative sulfate reduction/oxidation as well as to thiosulfate metabolism. Cyanobacteriota and Planctomycetota were especially active in assimilatory sulfate reduction. Analysis of the aprA and soxB genes pointed to members of the order Burkholderiales (Gammaproteobacteria) as the most dominant and active along the temperature gradient for these genes. Changes in the diversity and activity of different sulfur-metabolizing bacteria in photoautotrophic microbial mats along a temperature gradient revealed their important role in hot spring environments, especially the main primary producers (Chloroflexota/Cyanobacteriota) and diazotrophs (Cyanobacteriota), showing that carbon, nitrogen, and sulfur cycles are highly linked in these extreme systems. © 2023 by the authors. |
| Panta Rhei benchmark dataset: socio-hydrological data of paired events of floods and droughts | Earth System Science Data | Kreibich, H.; Schröter, K.; Di Baldassarre, G.; Van Loon, A.; Mazzoleni, M.; Abeshu, G.; Agafonova, S.; Aghakouchak, A.; Aksoy, H.; Alvarez-Garreton, C.; Aznar, B.; Balkhi, L.; Barendrecht, M.; Biancamaria, S.; Bos-Burgering, L.; Bradley, C.; Budiyono, Y.; Buytaert, W.; Capewell, L.; Carlson, H.; Ca... | 2023 | Agua y Extremos | 10.5194/essd-15-2009-2023 | https://doi.org/10.5194/essd-15-2009-2023 | 2009-2023 | Vol: 15 Issue: 5 | 1866-3508 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | As the adverse impacts of hydrological extremes increase in many regions of the world, a better understanding of the drivers of changes in risk and impacts is essential for effective flood and drought risk management and climate adaptation. However, there is currently a lack of comprehensive, empirical data about the processes, interactions, and feedbacks in complex human-water systems leading to flood and drought impacts. Here we present a benchmark dataset containing socio-hydrological data of paired events, i.e. two floods or two droughts that occurred in the same area. The 45 paired events occurred in 42 different study areas and cover a wide range of socio-economic and hydro-climatic conditions. The dataset is unique in covering both floods and droughts, in the number of cases assessed and in the quantity of socio-hydrological data. The benchmark dataset comprises (1) detailed review-style reports about the events and key processes between the two events of a pair; (2) the key data table containing variables that assess the indicators which characterize management shortcomings, hazard, exposure, vulnerability, and impacts of all events; and (3) a table of the indicators of change that indicate the differences between the first and second event of a pair. The advantages of the dataset are that it enables comparative analyses across all the paired events based on the indicators of change and allows for detailed context- and location-specific assessments based on the extensive data and reports of the individual study areas. The dataset can be used by the scientific community for exploratory data analyses, e.g. focused on causal links between risk management; changes in hazard, exposure and vulnerability; and flood or drought impacts. The data can also be used for the development, calibration, and validation of socio-hydrological models. The dataset is available to the public through the GFZ Data Services (Kreibich et al., 2023, 10.5880/GFZ.4.4.2023.001). © 2023 Heidi Kreibich et al. |
| A large diffusion and small amplification dynamics for density classification on graphs | International Journal of Modern Physics C | Leal, L.; Montealegre, P.; Osses, A.; Rapaport, I. | 2023 | Ciudades Resilientes | 10.1142/S0129183123500560 | https://doi.org/10.1142/S0129183123500560 | art: 2350056 | Vol: 34 Issue: 5 | 0129-1831 | Thomson Reuters ISI (SCIE) | English | The density classification problem on graphs consists in finding a local dynamics such that, given a graph and an initial configuration of 0's and 1's assigned to the nodes of the graph, the dynamics converge to the fixed point configuration of all 1's if the fraction of 1's is greater than the critical density (typically 1/2) and, otherwise, it converges to the all 0's fixed point configuration. To solve this problem, we follow the idea proposed in [R. Briceño, P. M. de Espanés, A. Osses and I. Rapaport, Physica D 261, 70 (2013)], where the authors designed a cellular automaton inspired by two mechanisms: diffusion and amplification. We apply this approach to different well-known graph classes: complete, regular, star, Erdös-Rényi and Barabási-Albert graphs. © 2023 World Scientific Publishing Company. | |
| 1000 years of population, warfare, and climate change in pre-Columbian societies of the Central Andes | PLoS ONE | Lima, M.; Gayó, E.; Gurruchaga, A.; Estay, S.; Santoro, C. | 2023 | Ciudades Resilientes | 10.1371/journal.pone.0278730 | https://doi.org/10.1371/journal.pone.0278730 | arte0278730 | Vol: 18 Issue: 11 November | 19326203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Different Andean societies underwent processes of expansion and collapse during propitious or adverse climate conditions, resource boost or depletion along with population variations. Previous studies have emphasized that demographic collapses of polities in the Central Andes Area were triggered by warfare and the negative impacts of fluctuating climate (droughts) on crop productivity. Nevertheless, the interactions between climatic variability, demography and warfare have been less thoroughly evaluated. We develop population dynamic models to test feedback relationships between population growth, climate change and warfare in the Central Andes, where considerable regional hydroclimate variations have occurred over a millennium. Through population models, we found out that the rise and demise of social polities in the northern coast of the Central Andes appear to be a consequence of climate change. In contrast, for the highlands of Peru and the Titicaca basin, population models suggest that warfare intensity has a negative effect on population growth rates. Copyright: © 2023 Lima et al. |
| Recent Deoxygenation of Patagonian Fjord Subsurface Waters Connected to the Peru–Chile Undercurrent and Equatorial Subsurface Water Variability | Global Biogeochemical Cycles | Linford, P.; Pérez‐Santos, I.; Montes, I.; Dewitte, B.; Buchan, S.; Narváez, D.; Saldías, G.; Pinilla, E.; Garreaud, R.; Díaz, P.; Schwerter, C.; Montero, P.; Rodríguez‐Villegas, C.; Cáceres‐Soto, M.; Mancilla‐Gutiérrez, G.; Altamirano, R. | 2023 | Agua y Extremos | 10.1029/2022GB007688 | https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022GB007688 | e2022GB007688 | Vol: 37 Issue: 6 | 0886-6236, 1944-9224 | Thomson Reuters ISI (SCIE) | English | In recent decades, global dissolved oxygen (DO) measurements have registered a decrease of ∼1%–2% in oxygen content, raising concerns regarding the negative impacts of ocean deoxygenation on marine life and the greenhouse gas cycle. By combining in situ data from 2016 to 2022, satellite remote sensing, and outputs from a physical-biogeochemical model, we revealed the deoxygenation process in the Patagonian fjords for the first time. Deoxygenation was associated with the advection of equatorial subsurface water (ESSW) mass into the northern region of Patagonia. An analysis of the circulation regime using the Mercator-Ocean global high-resolution model confirmed the importance of the Peru–Chile undercurrent (PCUC) in transporting the ESSW poleward, contributing to the entrance of ESSW into the northern Patagonian fjords. A mooring system installed in the water interchange area between the Pacific Ocean and Patagonian fjords detected a decreasing DO of −21.66 μmol L−1 over 7 years, which was explained by the increase in PCUC transport of 1.46 Sv. Inside the Puyuhuapi fjord system, a second DO time series exhibited more marked deoxygenation with −88.6 μmol L−1 over 3 years linked with the influence of ESSW and local processes, such as DO consumption by the organic matter degradation. The recent deoxygenation registered in the northern Patagonian fjords demonstrates the significance of studying DO in the context of reducing the global oxygen content, further warranting the quantification of the impacts of deoxygenation on life cycles of marine organisms that inhabit the Patagonian fjords and channels and the Humboldt current system. © 2023. American Geophysical Union. All Rights Reserved. | |
| Dormancy-break and germination requirements for seeds of the threatened Austral papaya (Carica chilensis) | Scientific Reports | Loayza, A.; García-Guzmán, P.; Carozzi-Figueroa, G.; Carvajal, D. | 2023 | Cambio de Uso de Suelo | 10.1038/s41598-023-44386-y | https://doi.org/10.1038/s41598-023-44386-y | art17358 | Vol: 13 Issue: 1 | 20452322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Seed dormancy is one of the most important adaptive mechanisms in plants, optimizing germination, seedling emergence, and establishment to ensure these processes occur when environmental conditions are favorable for plant survival and growth. Endemic to rocky environments of the southern Atacama Desert, the Austral papaya (Carica chilensis) is the papaya species with the southernmost distribution within the Caricaceae, thriving in the most extreme environmental conditions. This threatened plant exhibits low natural regeneration, primarily attributed to low germination, yet no information regarding seed dormancy release is available. In this study, we investigated the dormancy-break and germination requirements of C. chilensis. We hypothesized that if C. chilensis seeds exhibit physiological dormancy, then seeds with reduced moisture content and those treated with chemicals or growth hormones would exhibit higher germination percentages and faster germination than control seeds akin to other members of Caricacea. Our results confirmed this prediction and revealed that ultra-drying (< 3% moisture content) and treating seeds with sulfuric acid, gibberellic acid, or potassium nitrate are the most effective methods for germinating C. chilensis. Consequently, we suggest using these treatments to propagate this threatened papaya species. © 2023, Springer Nature Limited. |
| Levels of persistent organic pollutants (POPs) in the Antarctic atmosphere over time (1980 to 2021) and estimation of their atmospheric half-lives | Atmospheric Chemistry and Physics | Luarte, T.; Gómez-Aburto, V.; Poblete-Castro, I.; Castro-Nallar, E.; Hunneus, N.; Molina-Montenegro, M.; Egas, C.; Azcune, G.; Pérez-Parada, A.; Lohmann, R.; Bohlin-Nizzetto, P.; Dachs, J.; Bengtson-Nash, S.; Chiang, G.; Pozo, K.; Galbán-Malagón, C. | 2023 | Ciudades Resilientes | 10.5194/acp-23-8103-2023 | https://doi.org/10.5194/acp-23-8103-2023 | 8103-8118 | Vol: 23 Issue: 14 | 16807316 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Persistent organic pollutants (POPs) are synthetic compounds that were intentionally produced in large quantities and have been distributed in the global environment, originating a threat due to their persistence, bioaccumulative potential, and toxicity. POPs reach the Antarctic continent through long-range atmospheric transport (LRAT). In these areas, low temperatures play a significant role in the environmental fate of POPs, retaining them for a long time due to cold trapping by diffusion and wet deposition, acting as a net sink for many POPs. However, in the current context of climate change, the remobilization of POPs that were trapped in water, ice, and soil for decades is happening. Therefore, continuous monitoring of POPs in polar air is necessary to assess whether there is a recent re-release of historical pollutants back to the environment. We reviewed the scientific literature on atmospheric levels of several POP families (polychlorinated biphenyls - PCBs, hexachlorobenzene - HCB, hexachlorocyclohexanes - HCHs, and dichlorodiphenyltrichloroethane - DDT) from 1980 to 2021. We estimated the atmospheric half-life using characteristic decreasing times (TD). We observed that HCB levels in the Antarctic atmosphere were higher than the other target organochlorine pesticides (OCPs), but HCB also displayed higher fluctuations and did not show a significant decrease over time. Conversely, the atmospheric levels of HCHs, some DDTs, and PCBs have decreased significantly. The estimated atmospheric half-lives for POPs decreased in the following order: 4,4' DDE (13.5 years) > 4,4' DDD (12.8 years) > 4,4' DDT (7.4 years) > 2,4' DDE (6.4 years) > 2,4' DDT (6.3 years) > α-HCH (6 years) > HCB (6 years) > 3-HCH (4.2 years). For PCB congeners, they decreased in the following order: PCB 153 (7.6 years) > PCB 138 (6.5 years) > PCB 101 (4.7 years) > PCB 180 (4.6 years) > PCB 28 (4 years) > PCB 52 (3.7 years) > PCB 118 (3.6 years). For HCH isomers and PCBs, the Stockholm Convention (SC) ban on POPs did have an impact on decreasing their levels during the last decades. Nevertheless, their ubiquity in the Antarctic atmosphere shows the problematic issues related to highly persistent synthetic chemicals. © 2023 Thais Luarte et al. |
| A synergistic ozone-climate control to address emerging ozone pollution challenges | One Earth | Lyu, X.; Li, K.; Guo, H.; Morawska, L.; Zhou, B.; Zeren, Y.; Jiang, F.; Chen, C.; Goldstein, A.; Xu, X.; Wang, T.; Lu, X.; Zhu, T.; Querol, X.; Chatani, S.; Latif, M.; Schuch, D.; Sinha, V.; Kumar, P.; Mullins, B.; Seguel, R.; Shao, M.; Xue, L.; Wang, N.; Chen, J.; Gao, J.; Chai, F.; Simpson, I.; Si... | 2023 | Ciudades Resilientes | 10.1016/j.oneear.2023.07.004 | https://doi.org/10.1016/j.oneear.2023.07.004 | 964-977 | Vol: 6 Issue: 8 | 25903330 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Hybrid Gold Open Access | English | Tropospheric ozone threatens human health and crop yields, exacerbates global warming, and fundamentally changes atmospheric chemistry. Evidence has pointed toward widespread ozone increases in the troposphere, and particularly surface ozone is chemically complex and difficult to abate. Despite past successes in some regions, a solution to new challenges of ozone pollution in a warming climate remains unexplored. In this perspective, by compiling surface measurements at ∼4,300 sites worldwide between 2014 and 2019, we show the emerging global challenge of ozone pollution, featuring the unintentional rise in ozone due to the uncoordinated emissions reduction and increasing climate penalty. On the basis of shared emission sources, interactive chemical mechanisms, and synergistic health effects between ozone pollution and climate warming, we propose a synergistic ozone-climate control strategy incorporating joint control of ozone and fine particulate matter. This new solution presents an opportunity to alleviate tropospheric ozone pollution in the forthcoming low-carbon transition. © 2023 The Authors |
| The expressions of environmentalism in electoral competition: the case of Chile; [Las expresiones del ambientalismo en la competencia electoral: el caso de Chile] | Revista Chilena de Derecho y Ciencia Politica | Maillet, A.; Muñoz, N. | 2023 | 10.7770/rchdcp-V14N1-art62 | https://www.scielo.cl/scielo.php?pid=S0719-21502023000100209&script=sci_arttext | 1-28 | Vol: 14 Issue: 1 | 07189389 | SciELO | All Open Access; Gold Open Access | Spanish | There are few political science studies that address the participation in the electoral arena of environmental demands in Latin America. To fill this gap, we analyze in this exploratory work the electoral expressions of environ¬mentalism in Chile from 1993 to 2021. During this period, environmentalism has been expressed in the electoral arena through two options, sometimes complementary and at other times in competition. On the one hand, specific politi¬cal parties have been formed, and on the other, environmental mobilization activists have participated directly. Regardless of the approach adopted, the electoral re¬sults have been low until 2021, when environmen-talist candidates achieved good results in the elections for regional governors and conventional constituents. However, in the legislative elections of 2022 the result was again low, but at the same time environmental demands have been given exposure by actors such as candidate, and subsequently President, Gabriel Boric. Thus, it remains to be seen whether an electoral expression of environmentalism will become consolidated in Chile. © 2023, Catholic University of Temuco Faculty of Law Economics and Administrative Sciences. All rights reserved. | |
| Spatio-temporal multidisciplinary analysis of socio-environmental conditions to explore the COVID-19 early evolution in urban sites in South America | Heliyon | Mantilla Caicedo, G.; Rusticucci, M.; Suli, S.; Dankiewicz, V.; Ayala, S.; Caiman Peñarete, A.; Díaz, M.; Fontán, S.; Chesini, F.; Jiménez-Buitrago, D.; Barreto Pedraza, L.; Barrera, F. | 2023 | Zonas Costeras | 10.1016/j.heliyon.2023.e16056 | https://doi.org/10.1016/j.heliyon.2023.e16056 | art: e16056 | Vol: 9 Issue: 5 | 2405-8440 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | This study aimed to analyse how socio-environmental conditions affected the early evolution of COVID-19 in 14 urban sites in South America based on a spatio-temporal multidisciplinary approach. The daily incidence rate of new COVID-19 cases with symptoms as the dependent variable and meteorological-climatic data (mean, maximum, and minimum temperature, precipitation, and relative humidity) as the independent variables were analysed. The study period was from March to November of 2020. We inquired associations of these variables with COVID-19 data using Spearman's non-parametric correlation test, and a principal component analysis considering socio economic and demographic variables, new cases, and rates of COVID-19 new cases. Finally, an analysis using non-metric multidimensional scale ordering by the Bray-Curtis similarity matrix of meteorological data, socio economic and demographic variables, and COVID-19 was performed. Our findings revealed that the average, maximum, and minimum temperatures and relative humidity were significantly associated with rates of COVID-19 new cases in most of the sites, while precipitation was significantly associated only in four sites. Additionally, demographic variables such as the number of inhabitants, the percentage of the population aged 60 years and above, the masculinity index, and the GINI index showed a significant correlation with COVID-19 cases. Due to the rapid evolution of the COVID-19 pandemic, these findings provide strong evidence that biomedical, social, and physical sciences should join forces in truly multidisciplinary research that is critically needed in the current state of our region. © 2023 |
| Extreme harmful algal blooms, climate change, and potential risk of eutrophication in Patagonian fjords: Insights from an exceptional Heterosigma akashiwo fish-killing event | Progress in Oceanography | Mardones, J.; Paredes-Mella, J.; Flores-Leñero, A.; Yarimizu, K.; Godoy, M.; Artal, O.; Corredor-Acosta, A.; Marcus, L.; Cascales, E.; Pablo Espinoza, J.; Norambuena, L.; Garreaud, R.; González, H.; Iriarte, J. | 2023 | Agua y Extremos | 10.1016/j.pocean.2022.102921 | https://www.sciencedirect.com/science/article/pii/S007966112200180X | 102921 | Vol: 210 | 00796611 | Thomson Reuters ISI (SCIE) | English | The Patagonian fjords have experienced intense harmful algal blooms (HABs) in the last decade, affecting important aquaculture areas in southern Chile. Climatic anomalies have recently triggered ‘super blooms’ of opportunistic toxic microalgal genera, especially due to persistent thermal stratification which likely provides an optimal niche for HABs development in fjord systems. In March-April 2021, an intense and widespread bloom of the raphidophyte Heterosigma akashiwo caused high salmon mortalities (>6,000 t) in the Comau fjord, Los Lagos Region. A climate variability analysis showed the effects of the positive phase of the Southern Annular Mode (SAM > 1.2 hPa) overcame those of La Niña (Niño3.4 = -0.9 °C) leading to an intense drought on the northern part of Patagonia with record low rainfall (the 2nd driest summer in the last 70 years) and increased water temperature. A regional satellite analysis revealed an extreme and persistent shallow Mixed Layer Depth (MLD) during summer periods since 2019 within the inland seas. In situ vertical fine-resolution measurements during the bloom event showed high cell abundances in the first 3 m of the water column (max. ∼ 70,000 cells mL−1), associated with warmer water temperature (∼15.5 – 17.5 °C), low salinity (∼25–30 psu), moderate to high dissolved oxygen (5 – 8.5 mg/L) and extremely high fluorescence signals in dense superficial cell aggregations (max. 74.9 µg/L). A 18S rRNA metabarcoding analysis formally confirmed the presence of H. akashiwo and its almost monospecific bloom development at the water surface. HPLC pigment analysis showed the carotenoid fucoxanthin in high proportion (48.8 %) compared to other photosynthetic pigments, becoming a potential pigment biomarker for early satellite H. akashiwo detection. Cell growth and cytotoxic in vitro experiments revealed high phenotypic plasticity of Chilean H. akashiwo against sudden changes in salinity. An RTgill-W1 gill cell assay revealed high cytotoxic activity (viability down to ∼ 50 – 30 % of controls) only at high cell abundances (>40,000H. akashiwo cells mL−1), which was in accordance with histological examination of moribund salmon that showed gill damage and circulatory disorders mainly due to long-term exposure to hypoxic conditions and not to potent cytotoxic effects. The Party-MOSA particles dispersion model revealed a high retention of water masses within the Comau fjord during the H. akashiwo outbreak, a scenario that may have boosted fish kills due to enhanced cells patchiness, ichthyotoxins persistence and hypoxic conditions. A historical dissolved inorganic nutrient data analysis showed that inner Patagonian fjords maintain low N and P concentrations including those environments considered of high eutrophication risk. Low N:P (<16:1) ratios measured at Comau fjord during the 2021 suggests that toxic flagellates growth could be favored over diatoms; however, low N:Si (<1:1 – N deficiency) evidences a clear need for better understanding of the role of mixotrophy in the persistence of the 2021H. akashiwo bloom for several weeks. These results highlight the fact that HABs responses against climate drivers and potential eutrophication are not universal and need to be assessed yearly and locally, particularly because extreme droughts and intensive aquaculture in northern Patagonia are expected to continue throughout the 21st century. © 2022 Elsevier Ltd | |
| Equivalent impacts of logging and beaver activities on aboveground carbon stock loss in the southernmost forest on Earth | Scientific Reports | Miranda, A.; Hoyos-Santillan, J.; Lara, A.; Mentler, R.; Huertas-Herrera, A.; Toro-Manríquez, M.; Sepulveda-Jauregui, A. | 2023 | Cambio de Uso de Suelo | 10.1038/s41598-023-45657-4 | https://doi.org/10.1038/s41598-023-45657-4 | art18350 | Vol: 13 Issue: 1 | 20452322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The conservation of forest landscapes is crucial for global climate strategies, and the forest in Tierra del Fuego, located in Patagonia, represents the southernmost example on Earth. These ecosystems are critical for Chile’s roadmap toward carbon neutrality. Unfortunately, these ecosystems have been impacted by logging and beaver activities. Currently, the precise contribution of each driver to forest cover and carbon stock loss remains insufficiently quantified, impeding effective policymaking and the implementation of strategies to safeguard and enhance carbon stocks in these ecosystems. In this study, we conducted an assessment of forest carbon stock loss resulting from both logging and beaver activities in Chilean Tierra del Fuego from 1986 to 2019. While beavers have received significant attention for their substantial contribution to forest cover loss (56.1% forest cover, ≈ 1.4 MtC), our findings suggest that logging has nearly equally contributed to carbon stock depletion (43.8% forest cover, ≈ 1.2 MtC). Consequently, the prevailing focus on beavers has obscured the ongoing logging-induced carbon stock loss. The implications of our study highlight the urgency for comprehensive consideration of both drivers in Chile’s climate strategy to fulfill the country’s mitigation commitments. © 2023, The Author(s). |
| Widespread synchronous decline of Mediterranean-type forest driven by accelerated aridity | Nature Plants | Miranda, A.; Syphard, A.; Berdugo, M.; Carrasco, J.; Gómez-González, S.; Ovalle, J.; Delpiano, C.; Vargas, S.; Squeo, F.; Miranda, M.; Dobbs, C.; Mentler, R.; Lara, A.; Garreaud, R. | 2023 | Agua y Extremos; Cambio de Uso de Suelo | 10.1038/s41477-023-01541-7 | https://doi.org/10.1038/s41477-023-01541-7 | 1810-1817 | Vol: 9 Issue: 11 | 20550278 | Thomson Reuters ISI (SCIE) | English | Large-scale, abrupt ecosystem change in direct response to climate extremes is a critical but poorly documented phenomenon1. Yet, recent increases in climate-induced tree mortality raise concern that some forest ecosystems are on the brink of collapse across wide environmental gradients2,3. Here we assessed climatic and productivity trends across the world’s five Mediterranean forest ecosystems from 2000 to 2021 and detected a large-scale, abrupt forest browning and productivity decline in Chile (>90% of the forest in <100 days), responding to a sustained, acute drought. The extreme dry and warm conditions in Chile, unprecedented in the recent history of all Mediterranean-type ecosystems, are akin to those projected to arise in the second half of the century4. Long-term recovery of this forest is uncertain given an ongoing decline in regional water balance. This dramatic plummet of forest productivity may be a spyglass to the future for other Mediterranean ecosystems. © 2023, The Author(s), under exclusive licence to Springer Nature Limited. | |
| Kanamycin treatment in the pre-symptomatic stage of a Drosophila PD model prevents the onset of non-motor alterations | Neuropharmacology | Molina-Mateo, D.; Valderrama, B.; Zárate, R.; Hidalgo, S.; Tamayo-Leiva, J.; Soto-González, A.; Guerra-Ayala, S.; Arriagada-Vera, V.; Oliva, C.; Diez, B.; Campusano, J. | 2023 | Zonas Costeras | 10.1016/j.neuropharm.2023.109573 | https://doi.org/10.1016/j.neuropharm.2023.109573 | art: 109573 | Vol: 236 | 0028-3908 | Thomson Reuters ISI (SCIE) | English | Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor alterations, which is preceded by a prodromal stage where non-motor symptoms are observed. Over recent years, it has become evident that this disorder involves other organs that communicate with the brain like the gut. Importantly, the microbial community that lives in the gut plays a key role in this communication, the so-called microbiota-gut-brain axis. Alterations in this axis have been associated to several disorders including PD. Here we proposed that the gut microbiota is different in the presymptomatic stage of a Drosophila model for PD, the Pink1B9 mutant fly, as compared to that observed in control animals. Our results show this is the case: there is basal dysbiosis in mutant animals evidenced by substantial difference in the composition of midgut microbiota in 8–9 days old Pink1B9 mutant flies as compared with control animals. Further, we fed young adult control and mutant flies kanamycin and analyzed motor and non-motor behavioral parameters in these animals. Data show that kanamycin treatment induces the recovery of some of the non-motor parameters altered in the pre-motor stage of the PD fly model, while there is no substantial change in locomotor parameters recorded at this stage. On the other hand, our results show that feeding young animals the antibiotic, results in a long-lasting improvement of locomotion in control flies. Our data support that manipulations of gut microbiota in young animals could have beneficial effects on PD progression and age-dependent motor impairments. © 2023 Elsevier Ltd | |
| Nuevo proceso constituyente y cambio climático: Aspectos a considerar en la redacción de la Nueva Constitución | Moraga Sariego, P.; Borquez, R.; Hervé, D.; Alonso, C. | 2023 | https://www.cr2.cl/nuevo-proceso-constituyente-cambio-climatico/ | cr2.cl | |||||||||
| Memoria Ambiental. La Historia de la Institucionalidad Ambiental, a 50 años del Golpe Militar | Revista de Derecho Ambiental | Moraga Sariego, P.; Ossandón Rosales, J.; Chahuán, F.; Sameshima, S. | 2023 | 10.5354/0719-4633.2023.73355 | https://revistaderechoambiental.uchile.cl/index.php/RDA/article/view/73355 | 1-30 | Vol: 2 Issue: 20 | 0719-4633, 0718-0101 | Not indexed | All Open Access; Gold Open Access | English | ||
| ¿Falta de certeza jurídica frente a la emergencia climática? o ¿necesidad de recordar cuáles son los deberes de los Estados? | Revista de Derecho Ambiental | Moraga, P. | 2023 | 10.5354/0719-4633.2023.71186 | https://revistaderechoambiental.uchile.cl/index.php/RDA/article/view/71186 | 1-7 | Vol: 1 Issue: 19 | 0719-4633, 0718-0101 | Not indexed | All Open Access; Gold Open Access | English | ||
| Drought increase since the mid-20th century in the northern South American Altiplano revealed by a 389-year precipitation record | Climate of the Past | Morales, M.; Crispín-DelaCruz, D.; Álvarez, C.; Christie, D.; Ferrero, M.; Andreu-Hayles, L.; Villalba, R.; Guerra, A.; Ticse-Otarola, G.; Rodríguez-Ramírez, E.; LLocclla-Martínez, R.; Sanchez-Ferrer, J.; Requena-Rojas, E. | 2023 | Agua y Extremos | 10.5194/cp-19-457-2023 | https://cp.copernicus.org/articles/19/457/2023/ | 457-476 | Vol: 19 Issue: 2 | 1814-9324 | Thomson Reuters ISI (SCIE) | English | Abstract. Given the short span of instrumental precipitation records in the South American Altiplano, longer-term hydroclimatic records are needed to understand the nature of climate variability and to improve the predictability of precipitation, a key natural resource for the socioeconomic development in the Altiplano and adjacent arid lowlands. In this region grows Polylepis tarapacana, a long-lived tree species that is very sensitive to hydroclimatic changes and has been widely used for tree-ring studies in the central and southern Altiplano. However, in the northern sector of the Peruvian and Chilean Altiplano (16–19∘ S) still exists a gap of high-resolution hydroclimatic data based on tree-ring records. Our study provides an overview of the temporal evolution of the late-spring–mid-summer precipitation for the period 1625–2013 CE at the northern South American Altiplano, allowing for the identification of wet or dry periods based on a regional reconstruction from three P. tarapacana chronologies. An increase in the occurrence of extreme dry events, together with a decreasing trend in the reconstructed precipitation, has been recorded since the 1970s in the northern Altiplano within the context of the last ∼4 centuries. The average precipitation over the last 17 years stands out as the driest in our 389-year reconstruction. We reveal a temporal and spatial synchrony across the Altiplano region of dry conditions since the mid-1970s. Independent tree-ring-based hydroclimate reconstructions and several paleoclimatic records based on other proxies available for the tropical Andes record this synchrony. The influence of El Niño–Southern Oscillation (ENSO) on the northern Altiplano precipitation was detected by our rainfall reconstruction that showed past drier conditions in our study region associated with ENSO warm events. The spectral properties of the rainfall reconstruction showed strong imprints of ENSO variability at decadal, sub-decadal, and inter-annual timescales, in particular from the Pacific NIÑO 3 sector. Overall, the recent reduction in precipitation in comparison with previous centuries, the increase in extreme dry events and the coupling between precipitation and ENSO variability reported by this work is essential information in the context of the growing demand for water resources in the Altiplano. This study will contribute to a better understanding of the vulnerability and resilience of the region to the projected evapotranspiration increase for the 21st century associated with global warming. |
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| Environmental evolution of western Tierra del Fuego (∼54°S) since ice-free conditions and its zonal/hemispheric implications | Quaternary Science Reviews | Moreno, P.; Lambert, F.; Hernández, L.; Villa-Martínez, R. | 2023 | Agua y Extremos; Ciudades Resilientes | 10.1016/j.quascirev.2023.108387 | https://doi.org/10.1016/j.quascirev.2023.108387 | art108387 | Vol: 322 | 02773791 | Thomson Reuters ISI (SCIE) | English | By virtue of its position adjacent to the Drake Passage, Tierra del Fuego in South America allows examining the vegetation and environmental history of the southernmost continental landmass outside Antarctica, and the evolution of the Southern Westerly Winds-Southern Ocean (SWW–SO) coupled system since the Last Glacial Maximum (LGM). For that purpose, we studied sediment cores from Lago Charquito, a small closed-basin lake in central-west Tierra del Fuego with a continuous lacustrine record since ∼17.3 ka. Ice-free conditions at the site imply a ∼70 km retreat of the Bahía Inútil glacier lobe from its LGM position during a ∼800-year interval, a trend that continued until its disappearance ∼100 km upstream from L. Charquito, ∼800 years later. Our palynological data show an open landscape dominated by cold-tolerant shrubs and herbs between ∼17.3–12.9 ka, with increases in precipitation of SWW origin at ∼16.3 ka, ∼14.7 ka, between ∼8.7–7.6 ka, and after ∼6.8 ka. Warming at ∼12.9 ka initiated an abrupt afforestation trend that stalled during the early Holocene (∼12–8.7 ka) owing to a precipitation decline and wildfires, and later resumed in response to invigorated SWW. We hypothesize that sparse Nothofagus tree populations inhabited the periphery of the Patagonian Ice Sheet (PIS) during the LGM and migrated toward the Andes contemporaneous with glacier recession as temperature rose during the Last Glacial Termination (T1). We posit that besides establishing topographic and climatic barriers for land biota, the PIS enabled the connectivity of cold-tolerant hygrophilous plant populations along a humid fringe adjacent to its land-based perimeter, despite the presumably dry conditions downwind from the eastern PIS margin. Our results suggest that southward shifts or expansion of the SWW toward or beyond Tierra del Fuego enhanced upwelling and ventilation of deep waters in the SO, northward shifts or weakening had the opposite effect. We observe that the time evolution of atmospheric CO2 concentrations, high-latitude air and sea-surface temperatures, and sea level during T1 fall short in explaining the timing and abruptness of the Bahía Inútil glacier lobe collapse, and quite possibly multiple other glacier lobes from the PIS. © 2023 Elsevier Ltd | |
| Fires and rates of change in the temperate rainforests of northwestern Patagonia since ∼18 ka | Quaternary Science Reviews | Moreno, P.; Méndez, C.; Henríquez, C.; Fercovic, E.; Videla, J.; Reyes, O.; Villacís, L.; Villa-Martínez, R.; Alloway, B. | 2023 | Agua y Extremos | 10.1016/j.quascirev.2022.107899 | https://www.sciencedirect.com/science/article/pii/S0277379122005303?via%3Dihub | 107899 | Vol: 300 | 02773791 | Thomson Reuters ISI (SCIE) | English | We examine the temporal and spatial structure of wildfires and rates of vegetation change in the Pacific sector of northwestern Patagonia (40°-44°S) over the last ∼18,000 years. Macroscopic Charcoal Accumulation Rates (CHAR), a proxy of past local fires, shows a geographic variation that mirrors the modern north-to-south and low-to-high elevation increase in annual precipitation and decrease in precipitation seasonality, and the frequency of explosive volcanic events. Variability in past fires is evident at multiple timescales, with a significant multi-millennial low between ∼18–13.1 ka, an abrupt rise between ∼13.1–12.5 ka, and heightened fire activity between ∼11.4–8.2 ka with significant high values between ∼10–9.4 ka. A subsequent decline led to the lowest Holocene values between ∼6–5.4 ka, which rose and led to significant high values between ∼3.1 ka and the present. Andean and Western Upwind Environments share a multi-millennial structure of fire activity since ∼18 ka, overprinted by millennial and centennial-scale divergences. These differences underscore the role of explosive volcanism as a trigger or modulator of fire activity in the vicinity of Andean eruptive centers. We posit that fire activity in Western Upwind Environments was driven primarily by hydroclimate variations, namely changes in the intensity of the Southern Westerly Winds. Compilations of CHAR and the Rates of Change (ROC) parameter, a measure of the magnitude and rapidity of changes in the pollen records, covary during the onset of the interglacial fire regime at ∼13.1 ka and the last ∼4000 years, suggesting that fires catalyzed vegetation changes during specific intervals since the last glaciation. Highly mobile human occupations deployed along the coasts started at ∼6.2 ka, increased in pulses, and spread widely during the last two millennia. Covariation with CHAR and ROC since ∼4 ka suggests that hunter-gatherer-fishers contributed to enhanced fire activity and abrupt vegetation changes at regional scale. The ubiquitous fire maximum over the last four centuries relates to widespread settlement and associated large-scale land clearance conducted by European/Chilean settlers. © 2022 Elsevier Ltd | |
| Multiproxy Approach to Reconstruct the Fire History of Araucaria araucana Forests in the Nahuelbuta Coastal Range, Chile | Forests | Muñoz, A.; González, M.; Schneider-Valenzuela, I.; Klock-Barría, K.; Madariaga-Burgos, M.; Rodríguez, C.; Abarzúa, A.; Solari, M.; Martel-Cea, A.; Velásquez, B.; Paredes, B.; Guerrero, F.; Montiel, M.; Tapia-Marzán, V.; Riquelme, T.; Sheppard, P. | 2023 | Agua y Extremos; Cambio de Uso de Suelo | 10.3390/f14061082 | https://doi.org/10.3390/f14061082 | art1082 | Vol: 14 Issue: 6 | 19994907 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Multiproxy reconstructions of fire regimes in forest ecosystems can provide a clearer understanding of past fire activity and circumvent some limitations of single proxy reconstructions. While inferring fire history from scars in trees is the most precise method to reconstruct temporal fire patterns, this method is limited in Araucaria araucana forests by rot after fire injuries, successive fires that destroy the evidence and the prohibition of sample extraction from living Araucaria trees. In this context, dendrochemical studies in Araucaria trees and charcoal analysis from sediment cores can complement and extend the time perspective of the fire history in the relictual Araucaria-Nothofagus forests of the coastal range. We used dendrochemical, fire scar and charcoal records from the Nahuelbuta Coastal Range (37.8° S; 73° W) spanning the last 1000 years to reconstruct the fire history. The results indicate that periods with higher fire activity occurred between 1400 and 1650 AD. Long-term changes in the fire regime are related to increased climate variability over the last 1000 years, and especially with the arrival of settlers to the area after 1860 CE. The most severe fire events in the Nothofagus and Araucaria forests occurred when suitable fire-prone conditions were superimposed with high human densities. © 2023 by the authors. |
| New Observations of the Meteorological Conditions Associated with Particulate Matter Air Pollution Episodes in Santiago, Chile | Atmosphere | Muñoz-M, R.; Garreaud, R.; Rutllant, J.; Seguel, R.; Corral, M. | 2023 | Agua y Extremos; Ciudades Resilientes | 10.3390/atmos14091454 | https://doi.org/10.3390/atmos14091454 | art1454 | Vol: 14 Issue: 9 | 20734433 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The meteorological factors of the severe wintertime particulate matter (PM) air pollution problem of the city of Santiago, Chile, are investigated with newly available observations, including a 30 m tower measuring near-surface stability, winds and turbulence, as well as lower-tropospheric vertical profiles of temperature and winds measured by commercial airplanes operating from the Santiago airport (AMDAR database). Focusing on the cold season of the years 2017–2019, high-PM days are defined using an index of evening concentrations measured in the western part of the city. The diurnal cycles of the different meteorological variables computed over 25 PM episodes are compared against the overall diurnal cycles. PM episodes are associated with enhanced surface stability and weaker surface winds and turbulence during the evening and night. AMDAR vertical profiles of temperature and winds during episodes reveal a substantial lower-tropospheric warming attributed to enhanced regional subsidence, which is consistent with the shallower daytime boundary layer depth and the increased surface thermal amplitude observed during these days. An explanation for the weak surface winds during PM episodes was not evident, considering that these are clear days that would strengthen the local valley wind system. Two possible mechanisms are put forward to resolve this issue, which can be tested in the future using high-resolution numerical modeling validated with the new data described here. © 2023 by the authors. |
| Sources of Air Pollution Health Impacts and Co-Benefits of Carbon Neutrality in Santiago, Chile | Journal of Geophysical Research: Atmospheres | Nawaz, M.; Henze, D.; Huneeus, N.; Osses, M.; Álamos, N.; Opazo, M.; Gallardo, L. | 2023 | Ciudades Resilientes | 10.1029/2023JD038808 | https://doi.org/10.1029/2023JD038808 | arte2023JD038808 | Vol: 128 Issue: 19 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The population of Santiago, Chile, experiences air pollution above global health guidelines that is attributable in part to large anthropogenic emissions. This is compounded by geographic features and meteorological conditions that are prone to pollution accumulation as well as secondary pollution production. In recent years, there have been improvements in air quality; however, the future of air pollution in Santiago remains unclear due to its growing population and increased vehicle use. Mitigation efforts can be supported by characterizing sources of air pollution and estimating how changes in emissions could affect air quality in future years. In this study, we conduct simulations using a chemical transport model (GEOS-Chem) and perform adjoint calculations to characterize the relationship between health impacts associated with exposure to PM2.5, O3, and NO2 and anthropogenic emissions. We incorporate model updates in a new nested domain simulation over Central South America including local and regional anthropogenic emissions inventories for Chile. We estimate that 2,490 (1,360, 4,060) PM2.5- and O3-related premature deaths and 5,350 (1,320, 11,330) NO2-related new pediatric asthma cases were associated with pollution exposure in Santiago in 2015 and that a majority of these health impacts were attributable to anthropogenic emissions. We identify emissions from transportation, energy generation, and residential combustion as the leading contributors to these health impacts. Additionally, we estimate that Chile's commitment to attain carbon neutrality by 2050 could result in benefits in Santiago of 3,230 (1,240, 7,160) avoided deaths and 2,590 (640, 5,500) avoided pediatric asthma cases in 2050 compared to business-as-usual emissions. © 2023. The Authors. |
| The international and historical dimensions of Chilean water bureaucracy | Water International | Nicolas-Artero, C. | 2023 | Agua y Extremos | 10.1080/02508060.2023.2220512 | https://doi.org/10.1080/02508060.2023.2220512 | 480-499 | Vol: 48 Issue: 4 | 02508060 | Thomson Reuters ISI (SCIE) | English | This article explores the global dimension of Chilean water bureaucracy through the lens of its peripheral global position. The study relies on historical sources and identifies three periods. The first period extends from the end of World War II to the 1973 military coup. During this time, the establishment of water policies, influenced by multilateral and direct US aid, resulted in the formation of a water bureaucracy. US influence persisted during the dictatorship (1973-1990) due to support for the military junta. Since the transition to democracy, the water bureaucracy has relied on foreign capital to implement various water policies. © 2023 International Water Resources Association. | |
| Irrigated systems in Chile: towards the end of water turns?; [Les systèmes irrigués au Chili: vers la fin des tours d'eau ?] | Cahiers Agricultures | Nicolas-Artero, C. | 2023 | Agua y Extremos | 10.1051/cagri/2023021 | https://doi.org/10.1051/cagri/2023021 | art29 | Vol: 32 | 11667699 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | This paper studies the transformation of irrigated systems in the semi-arid Elqui Valley in Chile. We use the notion of hydrosocial territory to analyze the effects of new hydraulic infrastructures on irrigation practices and institutional water rules. The methodology is based on the collection and analysis of qualitative and quantitative data. The installation of new infrastructures associated with the rise of commercial agriculture, financed by the State, leads to a gradual abandonment of canals and water turns and disintegrates the collective decision-making process within the irrigators'associations. © C.N. Nicolas-Artero, Hosted by EDP Sciences 2023. |
| Mapa normativo de la Gobernanza de los Elementos | Nicolas-Artero, C.; Maillet, A.; Burotto, I.; Barrantes, G.; Hasbún, M.; Moraga, P.; Munoz, F.; Núñez, I.; Torres, B.; Venegas, S. | 2023 | 10.17605/OSF.IO/JFQ8N | https://osf.io/jfq8n/ | Open Science Framework | Spanish | El Mapa Normativo de la Gobernanza Climática de los Elementos (en Chile), que sigue al Informe a las Naciones "Gobernanza Climática de los Elementos" publicado en 2021, tiene como objetivo compilar las normativas existentes —incluyendo textos legales y reglamentarios— que influyen en la gobernanza de los cuatro elementos: agua, aire, tierra y fuego. Este mapa se presenta como una herramienta diseñada para facilitar la identificación de las normativas pertinentes en el contexto chileno, así como de los actores clave que las regulan y las acciones específicas que abordan los desafíos y problemas socioambientales en distintas escalas: nacional, regional, comunal e internacional. El Mapa normativo parte del postulado de que todo problema socioambiental está producido por una falla o insuficiencia del marco normativo vigente y/o su implementación. Para cada desafío o problema socioambiental identificado, se asocia una acción específica que se rige por una normativa existente. Al hacer esta relación entre el problema, la acción y la normativa, se configura un marco de referencia legal. Este marco no solo es específico, al centrarse en una acción concreta, sino también regulado, al fundamentarse en leyes o reglamentos vigentes. Este enfoque optimiza la toma de decisiones y la implementación de políticas, proporcionando un punto de partida claro y legalmente respaldado para abordar el problema de manera más eficaz, tanto para responsables de toma de decisiones como para defensores del medio ambiente y público en general. Además, se identificaron “leyes transversales” que, si bien no definen o regulan explícitamente los problemas ambientales, resultan importantes para interpretar la Ley de Gobierno y Administración Regional y la Ley Orgánica de Municipalidades. | ||||||
| Population dynamics shifts by climate change: High-resolution future mid-century trends for South America | Global and Planetary Change | Nuñez-Hidalgo, I.; Meseguer-Ruiz, O.; Serrano-Notivoli, R.; Sarricolea, P. | 2023 | Ciudades Resilientes | 10.1016/j.gloplacha.2023.104155 | https://doi.org/10.1016/j.gloplacha.2023.104155 | art104155 | Vol: 226 | 09218181 | Thomson Reuters ISI (SCIE) | English | Population dynamics and climate change are the main challenges for the 21st century, especially in South America. Human populations will increase their exposure to novel climatic conditions in their territories, entangling and complicating health and social problems. We analyze how socioeconomic and climatic future pathways will evolve in South America, a land with high climatic and social heterogeneity. We use the Köppen–Geiger climate classification, population growth, and climate projections for the most likely climate change scenarios for the 2050s based on the CHELSA dataset. We found that tropical and arid climates extend between 4.2%–2.5% and 2.6%–3.9%, replacing temperate climate zones, which will be reduced between 5.3%–4.5% for the Representative Concentration Pathways (RCP) 4.5 and 8.5 respectively. This implies a reduction of the Mediterranean, oceanic and polar climates. Population growth shows a significant relationship to increasing tropical and arid climates extension in almost all countries, meaning a higher exposure to more severe conditions for humans. This work opens up the chance of using possible guidelines to assist environmental management with key background information on expected climate types and population changes and address the potential effects of climate change on human settlements in the near future. © 2023 Elsevier B.V. | |
| Building back better in Latin America: examining the sustainability of COVID-19 recovery and development programs | Global Sustainability | O Ryan, R.; Villavicencio, A.; Gajardo, J.; Ulloa, A.; Ibarra, C.; Rojas, M. | 2023 | Gobernanza e Interfaz Ciencia y Política | 10.1017/sus.2023.7 | https://www.cambridge.org/core/product/identifier/S2059479823000078/type/journal_article | e12 | Vol: 6 | 2059-4798 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | Non-technical summary The significant outlays by countries in the Global South to recover from the COVID-19 crisis could have been an opportunity to build back better, advancing both a green recovery and addressing pressing social problems, thus advancing sustainability. To examine if this was the case, in this paper we analyze the expected impacts of recovery initiatives in five Latin American countries. Our results show that these programs do not support the possibility of building back better, weakly impacting 12 dimensions related to sustainability. We also propose a methodology to improve how sustainability concerns can be included in future choice of projects. Technical summary It has been argued that the significant outlays by governments across the world required to recover from the COVID-19 crisis can be an opportunity to build back better, that is, advance toward greener societies. In the Global South, which suffered acute social, economic and environmental problems prior to this health crisis, recovery initiatives would be best suited to focus on sustainable economic recovery which – along with the environmental concerns of a green recovery – could address pressing local problems. To this end, we analyzed the expected impacts of recovery initiatives in five Latin American countries on each of 71 sustainability criteria. These criteria are based on the UN sustainable development goals and other relevant literature related to sustainable development. Using principal component analysis, criteria are grouped into 12 dimensions. Our results show that recovery programs examined do not take advantage of the possibility of building back better, and many relevant dimensions related to a sustainable recovery are only weakly considered. Our methodology provides a step forward toward supporting governments in their efforts to identify better policies and investment projects and consequently put together packages of initiatives that advance on sustainability, green recovery or other long-term goals they may have. Social media summary Methodology to analyze COVID-19 recovery packages shows small impact on sustainability in five Latin American countries. |
| Assessment of the potential impacts of a carbon tax in Chile using dynamic CGE model | Journal of Cleaner Production | O'Ryan, R.; Nasirov, S.; Osorio, H. | 2023 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.jclepro.2023.136694 | https://doi.org/10.1016/j.jclepro.2023.136694 | art: 136694 | Vol: 403 | 0959-6526 | Thomson Reuters ISI (SCIE) | English | Carbon taxes have been proposed as a major instrument to mitigate carbon emissions and promote an energy transition to low carbon sources. However, its adoption remains politically challenging, particularly amid rising inflation and energy prices. Despite the need for more aggressive action on carbon mitigation to reach the Paris Agreement goals, few countries in Latin America have adopted carbon taxes and the tax levels are relatively low. A key concern for these countries, is to adequately assess the tradeoffs between stricter emission goals and the potential negative economy wide as well as sectoral and distributive impacts. In this context, in this paper we first propose a step by step approach to enhance an existing dynamic Computable General Equilibrium (CGE) model for Chile based on OECD's Green model. The contribution of this research is twofold. Firstly, emission factors are estimated and the development of the electricity sector is aligned with the expectations of decision makers. As a result, credible emission and energy sector development forecasts are generated by the model, that are in line with what policymakers expect to happen based on other bottom-up engineering models. Secondly, this baseline is then used in the CGE model to examine the use of a carbon tax to reach Chile's first Nationally Determined Contribution. The required tax level is determined together with CO2 emissions and the economywide, sectoral and distributive impacts. The results allow concluding about the applicability of carbon taxes and possible complementary measures. © 2023 Elsevier Ltd | |
| Spatial analysis of paleoclimate variations based on proxy records in the south-central Andes (18°- 35° S) from 32 to 4 ka | Quaternary Science Reviews | Orellana, H.; Latorre, C.; García, J.; Lambert, F. | 2023 | Ciudades Resilientes | 10.1016/j.quascirev.2023.108174 | https://doi.org/10.1016/j.quascirev.2023.108174 | art108174 | Vol: 313 | 02773791 | Thomson Reuters ISI (SCIE) | English | The long-term climate dynamics of the central Andes are part of an ongoing international research effort to reconstruct past climatic variations and sensitivity to different regional and global drivers during the last 50,000 years. The large number of diverse records, however, makes it difficult to compare results without an integrated spatial analysis that considers the nature of the record and whether they are integrating environmental conditions across a large basin (i.e., a lake record) or at a very local scale (such as a rodent midden). We compiled 92 records from the southern sector of the central Andes (SCA, 18°-35°S). Recalibrated records were further compared by converting the original author's interpretation into a scale of relative moisture anomalies (compared to the present) that ranges from −2 (very dry) to very wet (+2). Moisture anomaly maps were generated for intervals at 4, 6, 9.5, 14, 17, 21 and 32 ka BP (103 calibrated 14C years before present) using records within a 5% age uncertainty. Our compilations show a surprising degree of agreement in the extent and magnitude of past climate changes during late Pleistocene, but less spatial agreement during the Holocene. The TRACE21 transient climate model shows similar results, with better agreement during the Pleistocene compared to the Holocene. Our analyses not only reveal discrepancies between proxy record interpretations at sites from the same region but show which regions in the SCA require more study. © 2023 Elsevier Ltd | |
| Two Congeneric Shrubs from the Atacama Desert Show Different Physiological Strategies That Improve Water Use Efficiency under a Simulated Heat Wave | Plants | Ostria-Gallardo, E.; Zúñiga-Contreras, E.; Carvajal, D.; de La Peña, T.; Gianoli, E.; Bascuñán-Godoy, L. | 2023 | Cambio de Uso de Suelo | 10.3390/plants12132464 | https://doi.org/10.3390/plants12132464 | art2464 | Vol: 12 Issue: 13 | 22237747 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Desert shrubs are keystone species for plant diversity and ecosystem function. Atriplex clivicola and Atriplex deserticola (Amaranthaceae) are native shrubs from the Atacama Desert that show contrasting altitudinal distribution (A. clivicola: 0–700 m.a.s.l.; A. deserticola: 1500–3000 m.a.s.l.). Both species possess a C4 photosynthetic pathway and Kranz anatomy, traits adaptive to high temperatures. Historical records and projections for the near future show trends in increasing air temperature and frequency of heat wave events in these species’ habitats. Besides sharing a C4 pathway, it is not clear how their leaf-level physiological traits associated with photosynthesis and water relations respond to heat stress. We studied their physiological traits (gas exchange, chlorophyll fluorescence, water status) before and after a simulated heat wave (HW). Both species enhanced their intrinsic water use efficiency after HW but via different mechanisms. A. clivicola, which has a higher LMA than A. deserticola, enhances water saving by closing stomata and maintaining RWC (%) and leaf Ψmd potential at similar values to those measured before HW. After HW, A. deserticola showed an increase of Amax without concurrent changes in gs and a significant reduction of RWC and Ψmd. A. deserticola showed higher values of Chla fluorescence after HW. Thus, under heat stress, A. clivicola maximizes water saving, whilst A. deserticola enhances its photosynthetic performance. These contrasting (eco)physiological strategies are consistent with the adaptation of each species to their local environmental conditions at different altitudes. © 2023 by the authors. |
| Prokaryotic community dynamics and nitrogen-cycling genes in an oxygen-deficient upwelling system during La Niña and El Niño conditions | Environmental Microbiology | Pajares, S.; Merino-Ibarra, M.; Farías, L. | 2023 | Zonas Costeras | 10.1111/1462-2920.16362 | https://doi.org/10.1111/1462-2920.16362 | 1281-1299 | Vol: 25 | 1462-2912 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Dissolved oxygen regulates microbial distribution and nitrogen cycling and, therefore, ocean productivity and Earth's climate. To date, the assembly of microbial communities in relation to oceanographic changes due to El Niño Southern Oscillation (ENSO) remains poorly understood in oxygen minimum zones (OMZ). The Mexican Pacific upwelling system supports high productivity and a permanent OMZ. Here, the spatiotemporal distribution of the prokaryotic community and nitrogen-cycling genes was investigated along a repeated transect subjected to varying oceanographic conditions associated with La Niña in 2018 and El Niño in 2019. The community was more diverse during La Niña and in the aphotic OMZ, dominated by the Subtropical Subsurface water mass, where the highest abundances of nitrogen-cycling genes were found. The largest proportion of the Gulf of California water mass during El Niño provided warmer, more oxygenated, and nutrient-poor waters towards the coast, leading to a significant increase of Synechococcus in the euphotic layer compared with the opposite conditions during La Niña. These findings suggest that prokaryotic assemblages and nitrogen genes are linked to local physicochemical conditions (e.g. light, oxygen, nutrients), but also to oceanographic fluctuations associated with ENSO phases, indicating the crucial role of climate variability in microbial community dynamics in this OMZ. © 2023 The Authors. Environmental Microbiology published by Applied Microbiology International and John Wiley & Sons Ltd. |
| Hydrological connections in a glaciated Andean catchment under permafrost conditions (33°S) | Journal of Hydrology: Regional Studies | Pereira, S.; Díez, B.; Cifuentes-Anticevic, J.; Leray, S.; Fernandoy, F.; Marquardt, C.; Lambert, F. | 2023 | Ciudades Resilientes; Zonas Costeras | 10.1016/j.ejrh.2022.101311 | https://www.sciencedirect.com/science/article/pii/S221458182200324X | 101311 | Vol: 45 | 22145818 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Fresh water supply is critical along the Andes, where drought conditions over the past decade are projected to persist. At high Andean headwater catchments, frozen ground conditions are assumed to modulate groundwater flow paths and their hydrological signals at different timescales. However, knowledge of hydrological connections in subtropical Andean catchments is still very sparse. This study assessed hydrological connections and their impacts on groundwater contribution to baseflow in a headwater proglacial aquifer located in central Chile at 33° S and 3600 m a.s.l. We collected and analyzed snow, glacial stream, and groundwater spring water samples between 2019 and 2021. We combined of water isotope and metagenomic proxies with the hydraulic parameterization of the catchment to deliver mean transit time distributions through the proglacial aquifer. The new hydrological insights for the region include the finding that groundwater spring signals delivered sub-decadal transit times, implying likely origins from glacial or interstitial ice. Additionally, the stable isotope signature showed that groundwater consistently differs from snow and surface runoff. The 16S rRNA metabarcoding analyses demonstrated the presence of psychrophilic microorganisms in groundwater springs, supporting the idea of a late warm-season activation of interstitial ice due to thawing events associated with a differential relative-abundance of specific cryophilic bacteria. Finally, our results suggest hydrological connections and dampening timeframes between glaciers, proglacial areas, and groundwater springs, most likely from thawing sources. © 2023 The Authors |
| Warming and Drought Weaken the Carbon Sink Capacity of an Endangered Paleoendemic Temperate Rainforest in South America | Journal of Geophysical Research: Biogeosciences | Perez-Quezada, J.; Barichivich, J.; Urrutia-Jalabert, R.; Carrasco, E.; Aguilera, D.; Bacour, C.; Lara, A. | 2023 | Cambio de Uso de Suelo | 10.1029/2022JG007258 | https://doi.org/10.1029/2022JG007258 | art: e2022JG007258 | Vol: 128 Issue: 4 | 2169-8953 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Measurements of ecosystem carbon (C) fluxes in temperate forests are concentrated in the Northern Hemisphere, leaving the functionally diverse temperate forests in the Southern Hemisphere underrepresented. Here, we report 3 years (February 2018 to January 2021) of C fluxes, studied with eddy-covariance and closed chamber techniques, in an endangered temperate evergreen rainforest of the long-lived paleoendemic South American conifer Fitzroya cupressoides. Using classification and regression trees, we analyzed the most relevant drivers and thresholds of daily net ecosystem exchange (NEE) and soil respiration. The annual NEE showed that the forest was a moderate C sink during the period analyzed (−287 ± 38 g C m−2 year −1). We found that the capacity to capture C of the Fitzroya rainforests in the Coastal Range of southern Chile is optimal under cool and rainy conditions in the early austral spring (October–November) and decreases rapidly toward the summer dry season (January–February) and autumn. Although the studied forest type has a narrow geographical coverage, the gross primary productivity measured at the tower was highly representative of Fitzroya and other rainforests in the region. Our results suggest that C fluxes in paleoendemic cool F. cupressoides forests may be negatively affected by the warming and drying predicted by climate change models, reinforcing the importance of maintaining this and other long-term ecological research sites in the Southern Hemisphere. © 2023. American Geophysical Union. All Rights Reserved. |
| How much carbon is stored in the terrestrial ecosystems of the Chilean Patagonia? | Austral Ecology | Perez-Quezada, J.; Moncada, M.; Barrales, P.; Urrutia-Jalabert, R.; Pfeiffer, M.; Herrera, A.; Sagardía, R. | 2023 | Cambio de Uso de Suelo | 10.1111/aec.13331 | https://doi.org/10.1111/aec.13331 | 893-903 | Vol: 48 | 1442-9985 | Thomson Reuters ISI (SCIE) | English | We estimated the amount of carbon (C) stored in terrestrial ecosystems of the Chilean Patagonia and the proportion within protected areas. We used existing public databases that provide information on C stocks in biomass and soils. Data were analysed by ecosystem and forest type in the case of native forests. Our results show that some ecosystems have been more extensively studied both for their stocks in biomass and soils (e.g. forests) compared with others (e.g. shrublands). Forests and peatlands store the largest amount of C because of their large stocks per hectare and the large area they cover. The total amount of C stored per unit area varies from 261.7 to 432.8 Mg C ha−1, depending on the published value used for soil organic C stocks in peatlands, highlighting the need to have more precise estimates of the C stored in this and other ecosystems. The mean stock in national parks (508 Mg C ha−1) is almost twice the amount stored in undisturbed forests in the Amazon. State and private protected areas contain 58.9% and 2.1% of the C stock, respectively, playing a key role in protecting ecosystems in this once pristine area. © 2023 Ecological Society of Australia. | |
| On the interpretation of changes in the subtropical oxygen minimum zone volume off Chile during two La Niña events (2001 and 2007) | Frontiers in Marine Science | Pizarro-Koch, M.; Pizarro, O.; Dewitte, B.; Montes, I.; Paulmier, A.; Garçon, V.; Sepulveda, H.; Corredor-Acosta, A.; Aguirre, C.; Ramos, M. | 2023 | Zonas Costeras | 10.3389/fmars.2023.1155932 | http://hdl.handle.net/20.500.12816/5436 | art1155932 | Vol: 10 | 22967745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Oxygen minimum zones (OMZs) are extended oceanic regions for which dissolved oxygen concentration is extremely low. They are suspected to be expanding in response to global warming. However, currently, the mechanisms by which OMZ varies in response to climate variability are still uncertain. Here, the variability of the subtropical OMZ off central Chile of a regional coupled physical–biogeochemical regional model simulation was analyzed for the period 2000–2008, noting that its fluctuations were significant despite the relatively weak amplitude of the El Niño/Southern Oscillation (ENSO). In particular, the interannual variability in the OMZ volume (OMZVOL, defined as the volume with dissolved oxygen concentration (DO) ≤ 45μM) was approximately 38% larger than that of the seasonal cycle, with maximum and minimum anomalies of OMZVOL taking place during two cold La Niña (LN) years (2001 and 2007). The model analyses further reveal that these anomalies resulted from a combined effect of changes in (1) the oxygen-poor waters poleward transport by the Peru–Chile undercurrent (PCUC), (2) the intensity of quasi-zonal jets influencing the transport of water to and from the OMZ, and (3) the zonal DO transport related to mesoscale eddy activity. Specifically, the interannual variability of the PCUC modulated primarily the DO contents of the OMZ core [(DO) ≤ 20μM] and secondarily the OMZVOL, while cross-shore DO transport by the zonal jets and the eddy fluxes played a major role in ventilating and shaping the offshore extent of the OMZ. When the OMZVOL was maximum (minimum), the PCUC transport was slightly increased (reduced), which was associated with a reduction (increase) in the ventilation of the OMZ through negative (positive) anomalies of zonal advection and DO eddy fluxes. Our results demonstrate that significant natural interannual variability in the subtropical OMZ off Chile originates from the interplay between oceanic equatorial teleconnection (PCUC transport) and local non-linear dynamics (the zonal jets and mesoscale eddies). Copyright © 2023 Pizarro-Koch, Pizarro, Dewitte, Montes, Paulmier, Garçon, Sepulveda, Corredor-Acosta, Aguirre and Ramos. |
| Poor communication jeopardizes biodiversity | Conservation Biology | Pérez-Gómez, Á.; Repeto-Deudero, I.; Ojeda, F.; Gómez-González, S. | 2023 | Cambio de Uso de Suelo | 10.1111/cobi.14181 | https://doi.org/10.1111/cobi.14181 | e14181 | Vol: 37 | 08888892 | Thomson Reuters ISI (SCIE) | English | ||
| I Jornada sobre la Herriza - Valores y amenazas de un hábitat olvidado | Ecosistemas | Repeto Deudero, I.; Pérez Gómez, Á.; Gómez González, S.; Ojeda Copete, F. | 2023 | Cambio de Uso de Suelo | 10.7818/ECOS.2569 | https://doi.org/10.7818/ECOS.2569 | 2569 | Vol: 32 Issue: 2 | 16972473 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | Spanish | |
| Specialization patterns in symbiotic associations: A community perspective over spatial scales | Ecology and Evolution | Rodríguez-Arribas, C.; Martínez, I.; Aragón, G.; Zamorano-Elgueta, C.; Cavieres, L.; Prieto, M. | 2023 | Cambio de Uso de Suelo | 10.1002/ece3.10296 | https://doi.org/10.1002/ece3.10296 | arte10296 | Vol: 13 Issue: 7 | 20457758 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Specialization, contextualized in a resource axis of an organism niche, is a core concept in ecology. In biotic interactions, specialization can be determined by the range of interacting partners. Evolutionary and ecological factors, in combination with the surveyed scale (spatial, temporal, biological, and/or taxonomic), influence the conception of specialization. This study aimed to assess the specialization patterns and drivers in the lichen symbiosis, considering the interaction between the principal fungus (mycobiont) and the associated Nostoc (cyanobiont), from a community perspective considering different spatial scales. Thus, we determined Nostoc phylogroup richness and composition of lichen communities in 11 Nothofagus pumilio forests across a wide latitudinal gradient in Chile. To measure specialization, cyanobiont richness, Simpson's and d′ indices were estimated for 37 mycobiont species in these communities. Potential drivers that might shape Nostoc composition and specialization measures along the environmental gradient were analysed. Limitations in lichen distributional ranges due to the availability of their cyanobionts were studied. Turnover patterns of cyanobionts were identified at multiple spatial scales. The results showed that environmental factors shaped the Nostoc composition of these communities, thus limiting cyanobiont availability to establish the symbiotic association. Besides, specialization changed with the spatial scale and with the metric considered. Cyanolichens were more specialized than cephalolichens when considering partner richness and Simpson's index, whereas the d′ index was mostly explained by mycobiont identity. Little evidence of lichen distributional ranges due to the distribution of their cyanobionts was found. Thus, lichens with broad distributional ranges either associated with several cyanobionts or with widely distributed cyanobionts. Comparisons between local and regional scales showed a decreasing degree of specialization at larger scales due to an increase in cyanobiont richness. The results support the context dependency of specialization and how its consideration changes with the metric and the spatial scale considered. Subsequently, we suggest considering the entire community and widening the spatial scale studied as it is crucial to understand factors determining specialization. © 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. |
| Road transport exhaust emissions in Colombia. 1990–2020 trends and spatial disaggregation | Transportation Research Part D: Transport and Environment | Rojas, N.; Mangones, S.; Osses, M.; Granier, C.; Laengle, I.; Alfonso A., J.; Mendez, J. | 2023 | Ciudades Resilientes | 10.1016/j.trd.2023.103780 | https://doi.org/10.1016/j.trd.2023.103780 | 103780 | Vol: 121 | 13619209 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Green Open Access | English | Road traffic-related air pollution costs society in terms of lost lives, health problems, and financial damages. For directing regulatory actions and enhancing air quality, governments require emission inventories and trends over time across all geographic areas. This study provides a high-resolution spatially disaggregated on-road transportation emissions inventory in Colombia from 1990 to 2020. Our estimates followed a top-down approach that accounted for local characteristics such as fleet technology, fuel consumption, road infrastructure, and activity factors at a national and state level. We report annual CO2, CH4, NOx, VOCs, PM2,5, and black carbon at a spatial resolution of 0.01° x 0.01°. Economic crises (1998–2001), stringent emission requirements (2011), and the most recent sanitary quarantine (2020) all have an impact on emissions patterns, which grow at a slower rate than vehicle activity. For the annual emissions of CH4, CO, and PM2.5, the growth of motorbikes in the vehicle fleet is particularly crucial. © 2023 Elsevier Ltd |
| Land-use change and windstorms legacies drove the recolonization dynamics of laurel forests in Tenerife, Canary islands | Forest Ecosystems | Rozas, V.; García-López, M.; Olano, J.; Sangüesa-Barreda, G.; García-Hidalgo, M.; Gómez-González, S.; López-Rubio, R.; Fernández-Palacios, J.; García-González, I.; Lozano-López, L.; García-González, P.; García-Cervigón, A. | 2023 | Cambio de Uso de Suelo | 10.1016/j.fecs.2023.100098 | https://doi.org/10.1016/j.fecs.2023.100098 | art: 100098 | Vol: 10 | 2095-6355 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Laurel forests are quite relevant for biodiversity conservation and are among the island ecosystems most severely damaged by human activities. In the past, Canary laurel forests have been greatly altered by logging, livestock and agriculture. The remains of laurel forests are currently protected in the Canary Islands (Spain). However, we miss basic information needed for their restoration and adaptive management, such as tree longevity, growth potential and responsiveness to natural and anthropogenic disturbances. Using dendrochronological methods, we studied how forest dynamic is related to land-use change and windstorms in two well-preserved laurel forests on Tenerife Island. Wood cores were collected from over 80 trees per stand at three stands per forest. We used ring-width series to estimate tree ages and calculate annual basal area increments (BAI), cumulative diameter increases, and changes indicative of released and suppressed growth. Twelve tree species were found in all stands, with Laurus novocanariensis, Ilex canariensis and Morella faya being the most common species. Although some individuals were over 100 years old, 61.8%–88.9% of the trees per stand established between 1940 and 1970, coinciding with a post-war period of land abandonment, rural exodus and the onset of a tourism economy. Some trees have shown growth rates larger than 1 cm diameter per year and most species have had increasing BAI trends over the past decades. Strong growth releases occurred after windstorms at both sites, but the effects of windstorms were site-dependent, with the 1958 storm affecting mainly the eastern tip of the island (Anaga massif) and the 1991 storm the western tip (Teno massif). Given the great ability of laurel forest trees to establish after land use cessation and to increase growth after local disturbances such as windstorms, passive restoration may be sufficient to regenerate this habitat in currently degraded areas. © 2023 The Authors |
| The role of atmospheric rivers in rainfall-induced landslides: A study from the Elqui valley | Journal of Arid Environments | Rutllant, J.; Matus, F.; Rudloff, V.; Rondanelli, R. | 2023 | Zonas Costeras | 10.1016/j.jaridenv.2023.105016 | https://doi.org/10.1016/j.jaridenv.2023.105016 | 105016 | Vol: 216 | 01401963 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The purpose of the present study is to explore the synoptic-scale atmospheric circulation and water vapor transport that contribute to triggering landslides in the mid-Elqui basin (30°S, 70.5°W) since the early 20th century. A total of 12 storms during the modern period (1957–2017) were identified from various sources and analyzed using ERA5 Reanalysis data. An additional set of eight storms was included and characterized using 20th Century Reanalysis data. The results reveal that high-amplitude, deep troughs extending into the subtropics off the west coast of South America are ubiquitous in these storms. Maximum integrated water vapor transport from the northwest (NW) or west-northwest (WNW) was observed on the coast (25–30°S), with values sometimes exceeding 300 kg s-1 m-1, often reaching more than five standard deviations above the mean. Atmospheric rivers near the study region were found to be involved in all 12 modern landslide-producing storms. Moreover, most storms occur during the warm phase of the El Niño–Southern Oscillation (ENSO) and/or phases 7–8–1 of the Madden–Julian Oscillation (MJO). Backward-trajectory analyses indicate that in all but one of the modern storms, water vapor transport originated in the Central Tropical Pacific, where ocean warming characterizes the convective phases of ENSO and/or MJO. © 2023 The Authors |
| Información científica clave para la gestión y conservación del ecosistema biocultural del Pewén en Chile y Argentina | Bosque (Valdivia) | Sanguinetti, J.; Ditgen, R.; Donoso-Calderón, S.; Hadad, M.; Gallo, L.; González, M.; Ibarra, J.; Ladio, A.; Lambertucci, S.; Marchelli, P.; Mundo, I.; Nuñez, M.; Pauchard, A.; Puchi, P.; Relva, M.; Skewes, O.; Shepherd, J.; Speziale, K.; Vélez, M.; Salgado-Salomón, M.; Zamorano-Elgueta, C. | 2023 | Cambio de Uso de Suelo | 10.4067/s0717-92002023000100179 | https://doi.org/10.4067/s0717-92002023000100179 | 179-190 | Vol: 44 Issue: 1 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The forest of Araucaria araucana (“pewen” in Mapuche language), with its associated species of the genus Nothofagus, is unique from an evolutionary, biological and sociocultural point of view. Due to the interdependence and interrelation with the Mapuche-Pewenche people, it is considered a biocultural ecosystem. This work is a comprehensive binational review of current scientific information applicable to its management and conservation. The scientific community contributed with significant advances in the knowledge of: a) the interrelationships within and significance of this biocultural ecosystem; b) the regional genetic diversity; c) the fire regimen, its main drivers, its role in forest dynamics, and the recovery capacity of biodiversity in the face of different burn severities; d) the ecological role of seed production and its unusual interactions with granivorous fauna and cavity nesters; e) the decline and death of the canopy, due to environmental stress and the emergence of new pewen pathogens; f) the consequences of the invasion of pines and exotic mammals that alter the biological interactions and the original ecological processes, and g) the effects of cattle ranching and overexploitation of firewood and pine nuts on ecological integrity and biodiversity. This knowledge is considered essential to strengthen policies and strategies for protection, conservation, and management of this ecosystem, which is endemic, rare, regionally threatened, and globally declared endangered. Considering the identified problems, it is imperative to achieve social empowerment of the Mapuche-Pehuenche people, intercultural respect, and enforcing public policies for the conservation and sustainable use of these forests. © 2023, Universidad Austral de Chile. All rights reserved. |
| Explorando diferencias entre hombres y mujeres en las respuestas emocionales al cambio climático en Chile | Psicologías | Sapiains, R.; Bro, A.; Ugarte, A.; Inostroza, V.; Urquiza, A.; Zuleta, P. | 2023 | https://revistas.upr.edu/index.php/psicologias/article/view/20982 | 24-57 | Vol: 6 | 1948-559X | Latindex | Spanish | Understanding how different segments of society perceive and respond to climate change is key for determining effective interventions and policies aimed at building adaptive capacity. In this study, we use a sex perspective to explore the differences in emotional responses and levels of concern about climate change between men and women in Chile. Using data from a national survey on climate change (n=2170), applied in all regions, six hypotheses were tested. We find that women expressed more concern about climate change than men and more fear and sadness than men. Conversely, men expressed more pessimism than women. Also, individuals with children were more concerned about climate change than those without children. These findings highlight the importance of delving into the association between emotions and responses to climate change in Chile and Latin America. Finally, its implications for increasing people’s participation in climate action are discussed. | |||
| Policy brief | Movilidad humana en contexto de cambio climático y desastres socionaturales: Los casos de la provincia de Petorca y un macro-campamento de Antofagasta | Sapiains, R.; Castillo, C. | 2023 | https://www.cr2.cl/policy-brief-movilidad-humana-en-contexto-de-cambio-climatico-y-desastres-socionaturales-los-casos-de-la-provincia-de-petorca-y-un-macro-campamento-de-antofagasta/ | 5 | cr2.cl | ||||||||
| Precipitation extremes in the Puna of Atacama Desert, Chile: How to manage current and future uncertainty?; [Precipitación extrema en la Puna del Desierto de Atacama: ¿Cómo gestionar la incertidumbre actual y futura?] | Investigaciones Geograficas (Spain) | Sarricolea, P.; Romero-Aravena, H.; Serrano-Notivoli, R.; Meseguer-Ruiz, O.; Dubreuil, V.; Funatsu, B. | 2023 | Ciudades Resilientes | 10.14198/INGEO.22852 | https://doi.org/10.14198/INGEO.22852 | 51-66 | Vol: - Issue: 79 | 0213-4691 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access; Green Open Access | English | Chile is one of the Latin American countries most affected by Climate Change. There is a high level of uncertainty regarding the variability of precipitation and its projections in many regions of this country. This poses challenges for climate characterization and for defining strategies to reduce its risks. The study area is the Puna of Atacama Desert, Andean highlands located to the eastern side of the extreme arid lands, a region that concentrates the main copper and lithium mining at word scale, and where meteorological observations are scarce, with missing data and unreliable projections. Considering this data limitations, a daily precipitation database of 35 weather stations was constructed in order to evaluate some extreme precipitation indices that allow establishing changes between 1981-2017, in addition to spatial interpolations based on topography. It is concluded that most of the meteorological stations do not present significant trends of change, e.g. Extremely wet days (R99p), Wet days (RR) and Consecutive wet days (CWD). The index with the highest number of stations with a trend is CDD, which shows an increase in consecutive dry days. One of the main contributions of this research was to expand the number of observations and to generate maps of the spatial distribution of the indices of extremes. We are facing open questions regarding living with uncertainty, and meeting the challenges of maintaining records to increase the levels of certainty of climatic changes. © Pablo Sarricolea, Hugo Romero, Roberto Serrano-Notivoli, Oliver Meseguer-Ruiz, Vincent Dubreuil, Beatriz M. Funatsu. |
| Soluciones de base Natural (SbN) para conflictos de escasez hídrica en la Ecorregión Mediterránea de Chile | Revista de Geografía Norte Grande | Schneider-Valenzuela, I.; Brito-Escudero, C.; Aguilera-Betti, I.; Klock-Barría, K.; Celis-Diez, J.; Ugalde, A.; Jorquera-Martínez, L.; Venegas-González, A.; Carvallo, G.; Muñoz, A. | 2023 | https://ojs.uc.cl/index.php/RGNG/article/view/29093 | 1-35 | Vol: - Issue: 85 | 0718-3402 | Thomson Reuters ISI (SCIE; SSCI) | Spanish | ||||
| Informe de devolución: Estudio de contaminantes atmosféricos, determinantes e impactos en la Bahía de Quintero-Puchuncaví | Seguel, R.; Araya, N.; Alonso, C.; Silva, M.; Vargas, K.; Bozkurt, D.; Opazo, C.; Castillo, L. | 2023 | https://www.cr2.cl/informe-de-devolucion-estudio-de-contaminantes-atmosfericos-determinantes-e-impactos-en-la-bahia-de-quintero-puchuncavi/ | 15 | cr2.cl | La bahía de Quintero-Puchuncaví ha experimentado episodios de emergencia ambiental por décadas. Uno de los más severos provocó 1370 atenciones de urgencia en agosto de 2018. Si bien su causa continua en debate, la presencia de fuentes emisoras de compuestos orgánicos volátiles (COVs) motivaron al Ministerio del Medio Ambiente a elaborar una nueva norma de calidad de aire primaria a nivel nacional que regula de forma específica al benceno. A pesar de su potencial impacto en el medio ambiente y la salud pública, en Chile no hay mediciones sistemáticas de COVs. Durante 2022, el Centro de Ciencia del Clima y la Resiliencia CR2 puso a disposición sus capacidades científicas y tecnológicas para contribuir a la comprensión de los episodios de calidad de aire asociados a COVs en Quintero. Se realizó una campaña de mediciones en enero de 2022, cuyos resultados preliminares fueron presentados a la comunidad de Quintero en octubre del mismo año. La presentación fue acompañada de talleres participativos que permitieron conocer la percepción de los síntomas físicos y emocionales relacionados a la contaminación e identificar mejoras en la gobernanza en materia de calidad de aire. A continuación, se presentan los principales hallazgos y conclusiones de la investigación en un formato breve, directo y sin mayor uso de tecnicismos. Para mayor información sobre la investigación, le invitamos a visitar el sitio web www.cr2.cl/quintero |
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| Volatile organic compounds measured by proton transfer reaction mass spectrometry over the complex terrain of Quintero Bay, Central Chile | Environmental Pollution | Seguel, R.; Garreaud, R.; Muñoz, R.; Bozkurt, D.; Gallardo, L.; Opazo, C.; Jorquera, H.; Castillo, L.; Menares, C. | 2023 | Agua y Extremos; Ciudades Resilientes; Zonas Costeras | 10.1016/j.envpol.2023.121759 | https://doi.org/10.1016/j.envpol.2023.121759 | 121759 | Vol: 330 | 02697491 | Thomson Reuters ISI (SCIE) | English | This research provides new evidence regarding the different kinds of air quality episodes, and their underlying mechanisms, that frequently impact the urban area of Quintero Bay in Central Chile, which is located along complex coastal terrain and is surrounded by industries. The monitoring campaign was carried out in January 2022 and encompassed two distinctive meteorological regimes. The first part of the month was dominated by a coastal low centered to the south of Quintero, which resulted in prevailing northerly flow (or weak southerlies) and a deep cloud-topped marine boundary layer. After a 2–3-day transition, the latter collapsed, and a clear-sky regime ensued, which was characterized by a shallow boundary layer and strong southerly winds during the daytime that lasted until the end of the campaign. By using proton transfer reaction time of flight mass spectrometry (PTR–TOF–MS) at a high temporal resolution (1 s), we measured high levels of volatile organic compounds (VOCs) during air quality episodes in real time. The episodes detected were associated with different prevailing meteorological regimes, suggesting that different point sources were involved. In the first episode, propene/cyclopropane, butenes, benzene, toluene and ethylbenzene/xylenes were associated with north and northwesterly weak winds. Complaints associated with hydrocarbon odor were reported. The pollution originated from industrial and petrochemical units located to the north of Quintero, which transport and store natural gas, liquified petroleum gas and oil. The second episode was linked to an oil refinery located south of our measurement site. In this case, high levels of phenol, furan and cresols occurred under strong southwesterly winds. During this event, headaches and dizziness were reported. By contrast, the levels of other aromatic compounds (benzene, toluene, ethylbenzene/xylenes) were lower than in the first air pollution episode. © 2023 Elsevier Ltd | |
| Unprecedented warmth: A look at Spain's exceptional summer of 2022 | Atmospheric Research | Serrano-Notivoli, R.; Tejedor, E.; Sarricolea, P.; Meseguer-Ruiz, O.; de Luis, M.; Saz, M.; Longares, L.; Olcina, J. | 2023 | Ciudades Resilientes | 10.1016/j.atmosres.2023.106931 | https://doi.org/10.1016/j.atmosres.2023.106931 | art106931 | Vol: 293 | 01698095 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The warming of the global climate system is expected to result in significant socio-economic stress, primarily through the occurrence of extreme weather and climate events, with the potential for severe impacts on societies. This was evidenced by the vulnerability of European nations during the 2003 summer heatwave, which resulted in the death of tens of thousands of individuals due to heat-related complications. In this analysis, we examine the summer of 2022 in Spain, a Mediterranean country that is among the most impacted by the effects of climate change. A distinct pattern of the subtropical ridge in the 500 hPa geopotential height, which is typically linked to the occurrence of heatwaves in the Iberian Peninsula (IP), and the atmospheric blocking in the North Atlantic region facilitated the southerly flow of exceptionally warm air masses from Africa towards the IP, contributing to the sustained high temperatures throughout the summer season. Our results show that Spain experienced record-breaking temperatures in nearly half of the country that favored more frequent, intense, and longer-lasting heatwaves compared to previous historical records available from 1893. In general, despite normal rainfall conditions, the extremely high temperatures led to intense drought conditions in most areas. Finally, the paleoclimatic records suggest that the average summer temperature of 2022 was unprecedented within the last 700 years, and the driest within the last 279 in NE Spain. These findings highlight the need for measures to mitigate the effects of heat on at-risk populations, and to increase resilience and adaptation to climate change in the future. © 2023 The Authors |
| Climate-sensitive planning. Opportunities through the study of LCZs in Chile | Building and Environment | Smith Guerra, P.; Peralta Trigo, O.; Sarricolea Espinosa, P.; Thomas Cabrera, F.; Meseguer-Ruiz, O. | 2023 | Ciudades Resilientes | 10.1016/j.buildenv.2023.110444 | https://doi.org/10.1016/j.buildenv.2023.110444 | art110444 | Vol: 242 | 03601323 | Thomson Reuters ISI (SCIE) | English | Urban planning, through urban design and land use allocation, affects urban climate dynamics and patterns at different vertical layers of the urban boundary layer and spatial multiscale. Climate-sensitive urban planning and design draws attention to the consideration of climate parameters and their explanatory factors as a relevant element in decision-making. Local climate zones, defined from urban design variables such as building density and building height, allow for the recognition of homogeneous units useful for directing planning actions that allow cities and their population to adapt their climate behavior. This research compares the meso-scale climatic characteristics of the local climate zones proposed by Stewart and Oke for Chilean large cities located on an extensive latitudinal gradient (roughly 18°S to 45°S), on the coast of Chile and inland. In particular, the relationship between the behavior of surface temperature and vegetation is evaluated through the average Normalized Difference Vegetation Index (NDVI) for the decade (2008–2018). The results account for differences in the behavior of surface temperatures between climatic zones. In turn, vegetation is inversely related to the surface temperature, making it possible to distinguish the differences inside the LCZ, it being warmer in areas where the NDVI is lower. © 2023 | |
| Ecosystem services of Chilean sclerophyllous forests and shrublands on the verge of collapse: A review | Journal of Arid Environments | Smith-Ramírez, C.; Grez, A.; Galleguillos, M.; Cerda, C.; Ocampo-Melgar, A.; Miranda, M.; Muñoz, A.; Rendón-Funes, A.; Díaz, I.; Cifuentes, C.; Alaniz, A.; Seguel, O.; Ovalle, J.; Montenegro, G.; Saldes-Cortés, A.; Martínez-Harms, M.; Armesto, J.; Vita, A. | 2023 | Agua y Extremos; Cambio de Uso de Suelo | 10.1016/j.jaridenv.2022.104927 | https://www.sciencedirect.com/science/article/pii/S0140196322002221 | 104927 | Vol: 211 | 01401963 | Thomson Reuters ISI (SCIE) | English | Dryland forests are the areas most threatened by climate change, urbanization and land-use change simultaneously. Ecosystem services provided by Mediterranean dryland forests are have been in steep decline, and are extensively studied in the Mediterranean basin, however considerably less in other areas with Mediterranean climates. Knowledge of these services is necessary for the promotion of their conservation and restoration. Here, we synthesize current knowledge regarding the main ecosystem services provided by Chilean Mediterranean sclerophyllous forests and shrublands (SFSh). This knowledge allows for the valuation of SFSh in order to conserve, restore and study them. We found 158 studies, including technical reports, theses, and scientific literature regarding the social and environmental benefits derived from Chilean SFSh, though many did not use the term “ecosystem services” (ES). We found data on 19 ecosystem services with four or more studies per service. ES studies in Chile increased in number a couple years after Millennium Ecosystem Assessment published its synthesis in 2005. The most frequently reported services were provisioning services, especially medicinal plants and extracts. Despite the advances in knowledge, ecosystem services of SFSh appear to be rarely quantified, most frequently using oversimplified variable indicators. Services related to animal biodiversity, such as pollination and plague control, are poorly known. In recent years social studies of perception and valuation have increased, showing people's high valuation of SFSh. Additional studies are needed especially regarding water regulation and provision, as global warming will significantly reduce water supply in Mediterranean climates. Finally, we reflect on the advances necessary to enhance conservation, restoration and adaptation of ecosystems and their benefits to people, especially considering political, social and scientific factors. © 2023 Elsevier Ltd | |
| Fog-dependent forests in southern Atacama face threat from drought | Past Global Changes Magazine | Szejner, P.; Christie, D.; LeQuesne, C.; Gutierrez, A. | 2023 | 10.22498/pages.31.1.36 | https://www.pastglobalchanges.org/publications/pages-magazines/pages-magazine/137245 | 36-36 | Vol: 31 Issue: 1 | 2411605X, 24119180 | |||||
| Technical note: Skirt chamber - an open dynamic method for the rapid and minimally intrusive measurement of greenhouse gas emissions from peatlands | Biogeosciences | Thalasso, F.; Riquelme, B.; Gómez, A.; MacKenzie, R.; Aguirre, F.; Hoyos-Santillan, J.; Rozzi, R.; Sepulveda-Jauregui, A. | 2023 | Cambio de Uso de Suelo | 10.5194/bg-20-3737-2023 | https://doi.org/10.5194/bg-20-3737-2023 | 3737-3749 | Vol: 20 Issue: 18 | 17264170 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | We present a reliable and robust open dynamic chamber for measuring greenhouse gas exchange in peatlands with minimal disturbance of the ground. This chamber, called the "skirt chamber", is based on a transparent plastic film placed above an open frame made of sparse interwoven wires and expanded around the base of the chamber below a steel chain that ensures contact to the ground, avoiding damage, trenching, and cutting vegetation. Gas exchange is determined using a portable gas analyzer from a mass balance in which the imperfect sealing of the chamber to the ground is quantified through the injection of a methane pulse. The method was tested on a pristine peatland dominated by Sphagnum magellanicum located on Navarino Island in the subantarctic Magellanic ecoregion in Chile. Our results indicate that the skirt chamber allowed the determination of methane fluxes and ecosystem respiration in about 20 min, with a limit of detection of 0.185 mg CH4 m-2 h-1 and 173 mg CO2 m-2 h-1, respectively. We conclude that the skirt chamber is a minimally intrusive, fast, portable, and inexpensive method that allows the quantification of greenhouse gas emissions with high spatial resolution in remote locations and without delay. © Copyright: |
| Health and Safety Effects of Airborne Soil Dust in the Americas and Beyond | Reviews of Geophysics | Tong, D.; Gill, T.; Sprigg, W.; Van Pelt, R.; Baklanov, A.; Barker, B.; Bell, J.; Castillo, J.; Gassó, S.; Gaston, C.; Griffin, D.; Huneeus, N.; Kahn, R.; Kuciauskas, A.; Ladino, L.; Li, J.; Mayol‐Bracero, O.; McCotter, O.; Méndez‐Lázaro, P.; Mudu, P.; Nickovic, S.; Oyarzun, D.; Prospero, J.; Raga, ... | 2023 | Ciudades Resilientes | 10.1029/2021RG000763 | https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021RG000763 | e2021RG000763 | Vol: 61 Issue: 2 | 8755-1209, 1944-9208 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Risks associated with dust hazards are often underappreciated, a gap between the knowledge pool and public awareness that can be costly for impacted communities. This study reviews the emission sources and chemical, physical, and biological characteristics of airborne soil particles (dust) and their effects on human and environmental health and safety in the Pan-American region. American dust originates from both local sources (western United States, northern Mexico, Peru, Bolivia, Chile, and Argentina) and long-range transport from Africa and Asia. Dust properties, as well as the trends and interactions with criteria air pollutants, are summarized. Human exposure to dust is associated with adverse health effects, including asthma, allergies, fungal infections, and premature death. In the Americas, a well-documented and striking effect of soil dust is its association with Coccidioidomycosis, commonly known as Valley fever, an infection caused by inhalation of soil-dwelling fungi unique to this region. Besides human health, dust affects environmental health through nutrients that increase phytoplankton biomass, contaminants that diminish water supply and affect food (crops/fruits/vegetables and ready-to-eat meat), spread crop and marine pathogens, cause Valley fever among domestic and wild animals, transport heavy metals, radionuclides and microplastics, and reduce solar and wind power generation. Dust is also a safety hazard to road transportation and aviation, in the southwestern US where blowing dust is one of the deadliest weather hazards. To mitigate the harmful effects, coordinated regional and international efforts are needed to enhance dust observations and prediction capabilities, soil conservation measures, and Valley fever and other disease surveillance. © 2023. The Authors. |
| Large-scale and regional climatic influences on surface temperature and precipitation in the South Shetland Islands, northern Antarctic Peninsula | Anais da Academia Brasileira de Ciencias | Torres, C.; Bozkurt, D.; Arigony-Neto, J. | 2023 | Zonas Costeras | 10.1590/0001-3765202320230685 | https://doi.org/10.1590/0001-3765202320230685 | arte20230685 | Vol: 95 | 00013765 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Using data from SCAR observations, ERA5 reanalysis, and regional climate model simulations (RACMO), we examined the influence of large-and regional-scale climate forcing on temperature and precipitation variations in the South Shetland Islands (SSI). Specifically, we focused on understanding how regional climate indices influence the temporal variability of temperature and precipitation on the SSI. Our findings indicate that both large-and regional-scale climate indices significantly impact the interannual and seasonal temperature variability in the SSI. For instance, the Amundsen Sea Low, characterised by low-pressure systems over the Amundsen Sea, and sea ice extent in the northwestern part of the Weddell Sea, exert a strong influence on temperature variability (r from-0.64 to-0.87; p < 0.05). In contrast, precipitation variability in this region is primarily controlled by regional climatic indices. Particularly, anomalies in atmospheric and surface pressure over the Drake Passage region strongly regulate the interannual variability of precipitation in the SSI (r from-0.46 to-0.70; p < 0.05). Large-scale climatic indices demonstrate low but statistically significant correlations, including the Southern Annular Mode and deep convection in the central tropical Pacific. Given the importance of temperature and precipitation in the glacier changes, we recommend assessing the impact of the Drake region on SSI glaciers. © 2023, Academia Brasileira de Ciencias. All rights reserved. |
| Límites de la discusión sobre el Antropoceno | Estudios Públicos | Urquiza, A. | 2023 | 10.38178/07183089/0848230717 | https://www.estudiospublicos.cl/index.php/cep/article/view/2223 | 209-217 | Issue: 171 | 0718-3089, 0716-1115 | Erih; Latindex | Una reflexión desde las ciencias sociales sobre el concepto de Antropoceno debería considerar la aproximación del riesgo, es decir, de las consecuencias, los nuevos problemas y las nuevas reflexiones que emergen a partir de las repercusiones de las operaciones de la sociedad sobre el entorno ambiental. En ese contexto, la descripción de la geología tiene que ser considerada por las ciencias sociales como una observación disciplinaria más entre otras que remiten a cuestiones sociológicas, filosóficas e incluso epistemológicas. La categoría Antropoceno deja en evidencia el impacto de la sociedad en la naturaleza, permitiendo una mayor capacidad reflexiva. Sin embargo, esto no alcanza para una discusión sociológica informada —que el Antropoceno tampoco pretende— y no parece fructífero concentrarnos en su cuestionamiento. | |||
| Chile's road plans threaten ancient forests | Science (New York, N.Y.) | Urrutia-Jalabert, R.; Barichivich, J.; Gutiérrez, Á.; Miranda, A. | 2023 | Cambio de Uso de Suelo | 10.1126/science.adi0228 | https://doi.org/10.1126/science.adi0228 | 903 | Vol: 380 Issue: 6648 | 1095-9203 | Thomson Reuters ISI (SCIE) | English | During the United Nations Biodiversity Conference (COP15) in December 2022, nearly 200 countries, including Chile, agreed to halt biodiversity loss by 2030 and to take urgent actions to stop the extinction of endangered species. Despite this commitment, the Chilean government is pushing for the construction of a road that would cross the Alerce Costero National Park (1), an area of global importance for biodiversity conservation (2) and home to the endangered conifer Fitzroya cupressoides (3). Throughout the world, roads threaten biodiversity and ecosystem functions (4). Before pushing this project ahead, Chile should consider the likelihood that the road will undermine the country’s progress toward international environmental commitments. | |
| Ecophysiological Responses of Nothofagus obliqua Forests to Recent Climate Drying Across the Mediterranean-Temperate Biome Transition in South-Central Chile | Journal of Geophysical Research: Biogeosciences | Urrutia-Jalabert, R.; Barichivich, J.; Szejner, P.; Rozas, V.; Lara, A. | 2023 | Cambio de Uso de Suelo | 10.1029/2022JG007293 | https://doi.org/10.1029/2022JG007293 | art: e2022JG007293 | Vol: 128 Issue: 4 | 2169-8953 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The forests of south-central Chile are facing a drying climate and a megadrought that started in 2010. This study addressed the physiological responses of five Nothofagus obliqua stands across the Mediterranean-Temperate gradient (35.9°−40.3°S) using carbon isotope discrimination (Δ13 C) and intrinsic water use efficiency (iWUE) in tree rings during 1967–2017. Moreover, tree ring δ18O was evaluated in the northernmost site to better understand the effects of the megadrought in this drier location. These forests have become more efficient in their use of water. However, trees from the densest stand are discriminating more against 13C, probably due to reduced photosynthetic rates associated with increasing light competition. The strongest associations between climate and Δ13C were found in the northernmost stand, suggesting that warmer and drier conditions could have reduced 13C discrimination. Tree growth in this site has not decreased, and δ18O was negatively related to annual rainfall. However, a shift in this relationship was found since 2007, when both precipitation and δ18O decreased, while correlations between δ18O and growth increased. This implies that tree growth and δ18O are coupled in recent years, but precipitation is not the cause, suggesting that trees probably changed their water source to deeper and more depleted pools. Our research demonstrates that forests are not reducing their growth in central Chile, mainly due to a shift toward the use of deeper water sources. Despite a common climate trend across the gradient, there is a non-uniform response of N. obliqua forests to climate drying, being their response site-specific. © 2023. American Geophysical Union. All Rights Reserved. |
| Environmental control of the present-day sediment export along the extratropical Andes | Geomorphology | Vergara, I.; Garreaud, R.; Araneo, D.; Leyton, F. | 2023 | Agua y Extremos | 10.1016/j.geomorph.2023.108911 | https://doi.org/10.1016/j.geomorph.2023.108911 | art108911 | Vol: 441 | 0169555X | Thomson Reuters ISI (SCIE) | English | Understanding how the environmental factors that determine erosion operate is essential to know the past and future evolution of the Earth and adequately manage natural resources. In this work, the main controlling factors of the current sediment export in the western side of the extratropical Andes (20°-55°S) are investigated using multidecadal series of specific suspended sediment yields from 42 rivers, as well as land cover, climatic, cryospheric, topographic, seismological and geological data. Through an automatic selection of Generalized Additive Models based on predictability and complexity, it was found that the combined effects of extreme runoff, glacier cover and channel steepness explain ~90 % of the spatial variability of sediment export. The runoff effect varies from positive for hyper-arid and semi-arid settings to slightly negative for moderate and wet settings, probably because of an associated increase in vegetation coupled with a recurrence and magnitude of floods that becomes greater than the time it takes for the basins to generate sediment. Cryosphere and channel steepness influences were also observed on the average suspended sediment concentration, which is less associated with water availability and more associated with erodibility and sediment availability. © 2023 Elsevier B.V. | |
| A freshwater diatom perspective on the evolution of the southern westerlies for the past ∼14,000 years in southwestern Patagonia | Quaternary Science Reviews | Villacís, L.; Moreno, P.; Vilanova, I.; Henríquez, C.; Henríquez, W.; Villa-Martínez, R.; Sepúlveda-Zúñiga, E.; Maidana, N. | 2023 | Agua y Extremos | 10.1016/j.quascirev.2022.107929 | https://www.sciencedirect.com/science/article/pii/S0277379122005601 | 107929 | Vol: 301 | 02773791 | Thomson Reuters ISI (SCIE) | English | Conflicting, even opposite interpretations on the evolution of the Southern Westerly Winds (SWW) are evident in paleoenvironmental records from southwestern Patagonia since the last ice age. These divergences call for new approaches utilizing different, ideally independent indicators of paleoenvironmental/paleoclimatic change from sensitive sites in climatically relevant locations. Here we present a multidecadally resolved diatom record from Lago Cipreses (51°S), a small closed-basin lake located in a bedrock depression along the eastern foothills of the southern Patagonian Andes. The hydrological balance evolution of this isolated lake affords a direct tie with SWW intensity in a mountainous sector where zonal wind strength and local precipitation are highly correlated. We detect cold-tolerant diatoms (small fragilarioids) between ∼14-11.9 cal. ka BP followed by a shift to planktonic assemblages (Discostella pseudostelligera, Aulacoseira spp.) under warmer Holocene conditions. Diatom assemblages indicative of stratified water-column conditions (Discostella pseudostelligera, Achnanthidium aff tepidaricola, Achnanthidium sieminskae) reached their maximum stability between ∼9.1-7.4 cal. ka BP. Stronger water-column mixing is evident by an abrupt species turnover to Aulacoseira spp. between ∼7.4-3.1 cal. ka BP, superimposed on centennial-scale alternations between assemblages since ∼6.1 cal. ka BP. Cold-tolerant diatoms resurge at ∼3.1 cal. ka BP and persist until the present. Our record offers assemblage-based evidence we interpret as sub-centennial to multimillennial scale changes in hydroclimate indicative of: (i) strong SWW influence between ∼14-11.9 cal. ka BP, (ii) a transition between ∼11.9-11.3 cal. ka BP to weak SWW influence between ∼11.3-6.5 cal. ka BP, with a SWW minimum between ∼9.1-7.4 cal. ka BP, and (iii) strong SWW influence since ∼6.5 cal. ka BP, with a Holocene SWW maximum since ∼3.1 cal. ka BP. We posit that enhanced hydroclimate variability since ∼6.1 cal. ka BP attests to the onset of Southern Annular Mode-like changes at centennial-to sub-centennial timescales. We detect a remarkably coherent and synchronous response of terrestrial and aquatic ecosystems at local scale since ∼14 cal. ka BP, highlighting the overriding importance of variations in SWW influence in terrestrial and aquatic environments at multiple timescales. © 2022 Elsevier Ltd | |
| Dust transport enhanced land surface weatherability in a cooling world | Geochemical Perspectives Letters | Yang, Y.; Galy, A.; Zhang, J.; Lambert, F.; Zhang, M.; Zhang, F.; Fang, X. | 2023 | Ciudades Resilientes | 10.7185/geochemlet.2322 | https://doi.org/10.7185/geochemlet.2322 | 36-39 | Vol: 26 | 2410339X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The weatherability of exposed silicate rocks drives the efficiency of climatic feedback on the geological carbon cycle through silicate weathering. However, the controls and evolution of land surface weatherability are not fully understood. Tectonically induced exposure of fresh silicates can induce a wide range of weatherability, depending on the maturity and lithology of the exhumed rocks. Here, we propose that aeolian dust has potentially been pivotal in sustaining land surface weatherability during global cooling. Our analysis of palaeoclimate simulations shows an additional transport of 1072 ± 69 Tg yr−1 of dust to regions with precipitation of more than 400 mm yr−1 during the Last Glacial Maximum compared to the pre-industrial period. As dust mainly contains fresh minerals with high surface areas, such dust transport markedly increases land surface weatherability, yielding an additional atmospheric CO2 consumption of 0.431 ± 0.030 Tmol yr−1, which would offset the reduced silicate weathering induced by weaker climatic forcing. It is suggested that a dustier world could increase global land surface weatherability, leading to a more buffered carbon cycle that sustained low atmospheric CO2 levels. © 2023 European Association of Geochemistry. All rights reserved. |
| Advances in Simulating the Global Spatial Heterogeneity of Air Quality and Source Sector Contributions: Insights into the Global South | Environmental Science & Technology | Zhang, D.; Martin, R.; Bindle, L.; Li, C.; Eastham, S.; van Donkelaar, A.; Gallardo, L. | 2023 | Ciudades Resilientes | 10.1021/acs.est.2c07253 | https://pubs.acs.org/doi/10.1021/acs.est.2c07253 | 6955-6964 | Vol: 57 Issue: 17 | 0013-936X | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | High-resolution simulations are essential to resolve fine-scale air pollution patterns due to localized emissions, nonlinear chemical feedbacks, and complex meteorology. However, high-resolution global simulations of air quality remain rare, especially of the Global South. Here, we exploit recent developments to the GEOS-Chem model in its high-performance implementation to conduct 1-year simulations in 2015 at cubed-sphere C360 (∼25 km) and C48 (∼200 km) resolutions. We investigate the resolution dependence of population exposure and sectoral contributions to surface fine particulate matter (PM2.5) and nitrogen dioxide (NO2), focusing on understudied regions. Our results indicate pronounced spatial heterogeneity at high resolution (C360) with large global population-weighted normalized root-mean-square difference (PW-NRMSD) across resolutions for primary (62-126%) and secondary (26-35%) PM2.5 species. Developing regions are more sensitive to spatial resolution resulting from sparse pollution hotspots, with PW-NRMSD for PM2.5 in the Global South (33%), 1.3 times higher than globally. The PW-NRMSD for PM2.5 for discrete southern cities (49%) is substantially higher than for more clustered northern cities (28%). We find that the relative order of sectoral contributions to population exposure depends on simulation resolution, with implications for location-specific air pollution control strategies. © 2023 The Authors. Published by American Chemical Society. |
| A stability result for the identification of a permeability parameter on Navier–Stokes equations | Inverse Problems | Aguayo, J.; Osses, A. | 2022 | Ciudades Resilientes | 10.1088/1361-6420/ac6971 | https://iopscience.iop.org/article/10.1088/1361-6420/ac6971 | 075001 | Vol: 38 Issue: 7 | 0266-5611, 1361-6420 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Abstract In this work, we present a stability result for the inverse problem of recovering a smooth scalar permeability parameter given by the Brinkman’s law applied to the steady Navier–Stokes equations from local observations of the fluid velocity on a fixed domain. In comparison with we prove a logarithmic estimate under weaker assumptions, since our proof is based in a strategy that does not require pressure observations. This kind or result are useful for inverse problems in soft tissue elastographyFinally, we present some numerical tests that validate our theoretical results. |
| Fuzzy logic modelling to assess high resolution spatial urban climatic risk impact in Valparaiso, Chile | Alamos, N.; Billi, M.; Amigo, C.; Urquiza, A.; Winckler, P.; Larraguibel, C.; Contreras, M.; Muñoz, A.; Videla, J.; Vargas, V.; Casanova, J.; Ugalde, A.; Valdebenito, C. | 2022 | 10.17605/OSF.IO/2XTVS | https://osf.io/2xtvs/ | Open Science Framework | This collection of maps contains a set of 5 layers assessing the risk of the population of the Viña del Mar - Valparaiso conurbation (Chile) in the face of threats of extreme heat, storm surges, floods, forest fires and landslides. The maps have a resolution at the chilean census block level. The layers show as available attributes the overall level of risk and its components: threat (A), exposure (E), sensitivity (S) and response capacity (CR). To estimate the risk, the indices of A, E, S and CR are combined through a fuzzy logic methodology, which considers the use of causality rules co-constructed and validated with local experts and stakeholders. It should be considered that the values presented by each census block on the maps represent an ordering of risk (and of A, E, S and CR), where higher values indicate a greater risk than apples with lower values. The results are ordinal, ranging from mild, through moderately mild, to moderate, high or very high. Moreover, they are not absolute values, but rather relative to the specific case study and should not comparable or extrapolated to other study areas. | |||||||
| Dark Diazotrophy during the Late Summer in Surface Waters of Chile Bay, West Antarctic Peninsula | Microorganisms | Alcamán-Arias, M.; Cifuentes-Anticevic, J.; Castillo-Inaipil, W.; Farías, L.; Sanhueza, C.; Fernández-Gómez, B.; Verdugo, J.; Abarzua, L.; Ridley, C.; Tamayo-Leiva, J.; Díez, B. | 2022 | Zonas Costeras | 10.3390/microorganisms10061140 | https://www.mdpi.com/2076-2607/10/6/1140 | 1140 | Vol: 10 Issue: 6 | 2076-2607 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Although crucial for the addition of new nitrogen in marine ecosystems, dinitrogen (N2) fixation remains an understudied process, especially under dark conditions and in polar coastal areas, such as the West Antarctic Peninsula (WAP). New measurements of light and dark N2 fixation rates in parallel with carbon (C) fixation rates, as well as analysis of the genetic marker nifH for diazotrophic organisms, were conducted during the late summer in the coastal waters of Chile Bay, South Shetland Islands, WAP. During six late summers (February 2013 to 2019), Chile Bay was characterized by high NO3− concentrations (~20 µM) and an NH4+ content that remained stable near 0.5 µM. The N:P ratio was approximately 14.1, thus close to that of the Redfield ratio (16:1). The presence of Cluster I and Cluster III nifH gene sequences closely related to Alpha-, Delta- and, to a lesser extent, Gammaproteobacteria, suggests that chemosynthetic and heterotrophic bacteria are primarily responsible for N2 fixation in the bay. Photosynthetic carbon assimilation ranged from 51.18 to 1471 nmol C L−1 d−1, while dark chemosynthesis ranged from 9.24 to 805 nmol C L−1 d−1. N2 fixation rates were higher under dark conditions (up to 45.40 nmol N L−1 d−1) than under light conditions (up to 7.70 nmol N L−1 d−1), possibly contributing more than 37% to new nitrogen-based production (≥2.5 g N m−2 y−1). Of all the environmental factors measured, only PO43- exhibited a significant correlation with C and N2 rates, being negatively correlated (p < 0.05) with dark chemosynthesis and N2 fixation under the light condition, revealing the importance of the N:P ratio for these processes in Chile Bay. This significant contribution of N2 fixation expands the ubiquity and biological potential of these marine chemosynthetic diazotrophs. As such, this process should be considered along with the entire N cycle when further reviewing highly productive Antarctic coastal waters and the diazotrophic potential of the global marine ecosystem. |
| Surface Ammonia-Oxidizer Abundance During the Late Summer in the West Antarctic Coastal System | Frontiers in Microbiology | Alcamán-Arias, M.; Cifuentes-Anticevic, J.; Díez, B.; Testa, G.; Troncoso, M.; Bello, E.; Farías, L. | 2022 | Zonas Costeras | 10.3389/fmicb.2022.821902 | https://www.frontiersin.org/articles/10.3389/fmicb.2022.821902/full | 821902 | Vol: 13 | 1664-302X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Marine ammonia oxidizers that oxidize ammonium to nitrite are abundant in polar waters, especially during the winter in the deeper mixed-layer of West Antarctic Peninsula (WAP) waters. However, the activity and abundance of ammonia-oxidizers during the summer in surface coastal Antarctic waters remain unclear. In this study, the ammonia-oxidation rates, abundance and identity of ammonia-oxidizing bacteria (AOB) and archaea (AOA) were evaluated in the marine surface layer (to 30 m depth) in Chile Bay (Greenwich Island, WAP) over three consecutive late-summer periods (2017, 2018, and 2019). Ammonia-oxidation rates of 68.31 nmol N L −1 day −1 (2018) and 37.28 nmol N L −1 day −1 (2019) were detected from illuminated 2 m seawater incubations. However, high ammonia-oxidation rates between 267.75 and 109.38 nmol N L −1 day −1 were obtained under the dark condition at 30 m in 2018 and 2019, respectively. During the late-summer sampling periods both stratifying and mixing events occurring in the water column over short timescales (February–March). Metagenomic analysis of seven nitrogen cycle modules revealed the presence of ammonia-oxidizers, such as the Archaea Nitrosopumilus and the Bacteria Nitrosomonas and Nitrosospira , with AOA often being more abundant than AOB. However, quantification of specific amo A gene transcripts showed number of AOB being two orders of magnitude higher than AOA, with Nitrosomonas representing the most transcriptionally active AOB in the surface waters. Additionally, Candidatus Nitrosopelagicus and Nitrosopumilus , phylogenetically related to surface members of the NP-ε and NP-γ clades respectively, were the predominant AOA. Our findings expand the known distribution of ammonium-oxidizers to the marine surface layer, exposing their potential ecological role in supporting the marine Antarctic system during the productive summer periods. |
| Transformation Action Database / Base de datos acciones de transformación | Aldunce, P.; Guevara, G.; Munoz, F. | 2022 | 10.17605/OSF.IO/RC94T | https://osf.io/rc94t/ | Open Science Framework | This database consists of transformation initiatives, that include detailed metadata and description of processes that lead to profound changes, that translate into fundamentally different ways of thinking, actions, systems, and structures, usually large-scale. The content of the database began to be collected in 2020 and was obtained by reviewing scientific and non-scientific documents that have registered transformative actions in the world, web pages of national and international organizations, and conducting interviews, workshops and other information-gathering activities. | |||||||
| Les mobilisations autour de l’extractivisme. Circulation et potentiel heuristique d’un concept en voie de globalisation: | Revue internationale de politique comparée | Allain, M.; Maillet, A. | 2022 | 10.3917/ripc.283.0007 | https://www.cairn.info/revue-internationale-de-politique-comparee-2021-3-page-7.htm?ref=doi | 7-29 | Vol: Vol. 28 Issue: 3 | 1370-0731 | Scopus | ||||
| Refinement of the tephrostratigraphy straddling the northern Patagonian Andes (40–41°S): new tephra markers, reconciling different archives and ascertaining the timing of piedmont deglaciation | Journal of Quaternary Science | Alloway, B.; Pearce, N.; Moreno, P.; Villarosa, G.; Jara, I.; Henríquez, C.; Sagredo, E.; Ryan, M.; Outes, V. | 2022 | Agua y Extremos | 10.1002/jqs.3389 | https://onlinelibrary.wiley.com/doi/10.1002/jqs.3389 | 441-477 | Vol: 37 Issue: 3 | 0267-8179, 1099-1417 | Thomson Reuters ISI (SCIE) | English | We describe the stratigraphy, age, geochemistry and correlation of tephra from west to east across the northern Patagonian Andes (c. 40–41°S) with a view to further refining the eruptive history of this region back to the onset of the Last Glacial Termination (~18 cal. ka). Eastwards across the Andes, rhyodacite to rhyolitic tephra markers of dominantly Puyehue-Cordón Caulle source are persistently recognised and provide a stratigraphic context for more numerously erupted intervening tephra of basalt to basaltic–andesite composition. Tephra from distal eruptive centres are also recognised. West of the Andean Cordillera, organic-rich cores from a small closed lake basin (Lago Pichilafquén) reveal an exceptional high-resolution record of lowland vegetation–climate change and eruptive activity spanning the last 15 400 years. Three new rhyodacite tephra (BT6-T1, -T2 and -T4) identified near the base of the Pichilafquén record, spanning 13.2 to 13.9 cal. ka bp, can be geochemically matched with correlatives in basal andic soil sequences closely overlying regolith and/or basement rock. The repetitiveness of this tephrostratigraphy across this Andean transect suggests near-synchronous tephra accretion and onset of up-building soil formation under more stable (revegetating) ground-surface conditions following rapid piedmont deglaciation on both sides of the Cordillera by at least ~14 cal. ka bp. | |
| Seasonal Variations in Fjord Sediment Grain Size: A Pre‐requisite for Hydrological and Climate Reconstructions in Partially Glacierized Watersheds (Baker River, Patagonia) | Journal of Geophysical Research: Earth Surface | Amann, B.; Bertrand, S.; Alvarez‐Garreton, C.; Reid, B. | 2022 | Agua y Extremos | 10.1029/2021JF006391 | https://onlinelibrary.wiley.com/doi/10.1029/2021JF006391 | arte2021JF006391 | Vol: 127 Issue: 2 | 2169-9003, 2169-9011 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Fjord sediments are increasingly recognized as high-resolution archives of past hydrological and climate variability. Using them as such, however, requires a comprehensive understanding of the variables that affect their accumulation rates and properties. Here, we conduct a spatial and temporal study of sediment samples collected at the head of Martínez Channel (Chilean Patagonia, 48°S), to understand how the fjord's sediments register changes in the hydrology of Baker River, Chile's largest river in terms of mean annual discharge. We apply end-member modeling to particle-size distributions of: (a) river suspended sediments, (b) surface sediments collected along a proximal-distal transect at the fjord head, and (c) fjord sediments collected in a sequential sediment trap at 15-day resolution during two consecutive years. We then validate the use of the grain-size end members for hydrological and climate reconstructions, using a sediment core that covers the last 35 years. Results show that the river suspended sediments and fjord sediments are consistently composed of two grain-size subpopulations. The finest end member (EM1; mode 4.03 μm) reflects the meltwater contribution, which dominates in all but the winter season. The coarser end member (EM2; mode 18.7 μm) dominates in winter, when meltwater contribution is reduced, and is associated with rainfall. We show that the fluxes of EM1 and EM2 provide quantitative estimates of baseflow (r = 0.87, p < 0.001) and quickflow (r = 0.86, p < 0.001), respectively. Additionally, we propose that log (EM1/EM2) can be used to reconstruct meltwater production (r = 0.67, p < 0.001) and temperature (r = 0.81, p < 0.001) in the lower Baker River watershed. These results support the use of fjord sediments for quantitative reconstructions of hydrological and climate variability in partially glacierized watersheds. © 2022. American Geophysical Union. All Rights Reserved. |
| Prosopis L. woody growth in relation to hydrology in South America: A review | Dendrochronologia | Ambite, S.; Ferrero, M.; Piraino, S.; Badagian, J.; Muñoz, A.; Aguilera-Betti, I.; Gamazo, P.; Roig, F.; Lucas, C. | 2022 | Agua y Extremos | 10.1016/j.dendro.2022.126017 | https://linkinghub.elsevier.com/retrieve/pii/S1125786522000972 | 126017 | Vol: 76 | 11257865 | Thomson Reuters ISI (SCIE) | English | Arboreal species of the genus Prosopis L. have played an important role in the development of tree-ring research in arid and semi-arid ecoregions of South America. Given the distribution of Prosopis across a broad precipitation gradient from 0 to 2000 mm y−1 and its unique role as a phreatophyte, the relationship between Prosopis species growth and water has been a recurring theme over the past century. We conducted a systematic review of the literature addressing Prosopis and water research in South America, and combined site coordinates with GIS data of mean annual precipitation (MAP), elevation, biome, and soil moisture from online databases to understand the spatial distribution of research to date. We compiled 40 publications from 1931 to 2022, including results from 11 species of Prosopis among four countries, on the relationship between Prosopis spp and precipitation, groundwater levels, soil humidity, among other hydrological parameters. The spatial distribution of research sites spans tropical-subtropical and temperate latitudes from 4° to 35°S, excluding regions where the genus is present in Patagonia and northeastern South America. Studies covered a broad range of elevations from 30 to 3500 m a.s.l. but was limited to 1–730 mm y−1 MAP, excluding more humid climates where Prosopis occurs. Results obtained from 32 dendrochronological studies and eight studies relating to Prosopis and hydrology, were grouped into sub-disciplines of tree-ring formation and the hydrosystem, dendroclimatology, dendrohydrology, and dendroecology. The review highlights the unique affinities of Prosopis to arid conditions, and the use of tree rings as a proxy for historical droughts and variability in water tables. Nonetheless, there are opportunities to expand the geographical-climatological extent of Prosopis growth research to humid climates, as well as to incorporate novel techniques such as stable isotopes and vessel size chronologies to understand how this genus records hydrological change throughout South America. © 2022 Elsevier GmbH | |
| Lived environmental citizenship through intersectional lenses: The experience of female community leaders in rural Chile | Journal of Rural Studies | Arriagada, E.; Garcés Sotomayor, A.; Maillet, A.; Viveros Barrientos, K.; Zambra, A. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.jrurstud.2022.07.007 | https://linkinghub.elsevier.com/retrieve/pii/S0743016722001668 | 353-365 | Vol: 94 | 0743-0167 | Thomson Reuters ISI (SSCI) | English | The 2019 social uprising in Chile revealed the widespread discontent the citizens of this country experience. In particular, rural areas were part of this social mobilization during which discontent around environmental issues were particularly salient. However, we still know little about the daily experiences of environmental suffering outside urban areas, and the different ways individuals and collectives confront it. To tackle these issues and contribute to the broader discussion about environmental citizenship and non-traditional forms of mobilization and activism, we build on the experience of the “School for Female Leaders on Socio-environmental and Territorial Issues”, a research-action joint-venture project that brought together women from different non-urban districts of the Metropolitan Region with a team of social and social scientists and practitioners. Sharing experiences about environmental suffering and the particular ways female leaders respond led us to propose the concept of lived environmental citizenship, which accounts for the incompleteness these women felt in relation to the promises of formal citizenship, and their personal, community and political work to address it. This concept and the findings of our research contribute to enhancing discussions on gendered rural and environmental politics. © 2022 | |
| A general theory for temperature dependence in biology | Proceedings of the National Academy of Sciences | Arroyo, J.; Díez, B.; Kempes, C.; West, G.; Marquet, P. | 2022 | Zonas Costeras | 10.1073/pnas.2119872119 | https://pnas.org/doi/full/10.1073/pnas.2119872119 | e2119872119 | Vol: 119 Issue: 30 | 0027-8424, 1091-6490 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | At present, there is no simple, first principles–based, and general model for quantitatively describing the full range of observed biological temperature responses. Here we derive a general theory for temperature dependence in biology based on Eyring–Evans–Polanyi’s theory for chemical reaction rates. Assuming only that the conformational entropy of molecules changes with temperature, we derive a theory for the temperature dependence of enzyme reaction rates which takes the form of an exponential function modified by a power law and that describes the characteristic asymmetric curved temperature response. Based on a few additional principles, our model can be used to predict the temperature response above the enzyme level, thus spanning quantum to classical scales. Our theory provides an analytical description for the shape of temperature response curves and demonstrates its generality by showing the convergence of all temperature dependence responses onto universal relationships—a universal data collapse—under appropriate normalization and by identifying a general optimal temperature, around 25 ∘ C, characterizing all temperature response curves. The model provides a good fit to empirical data for a wide variety of biological rates, times, and steady-state quantities, from molecular to ecological scales and across multiple taxonomic groups (from viruses to mammals). This theory provides a simple framework to understand and predict the impact of temperature on biological quantities based on the first principles of thermodynamics, bridging quantum to classical scales. |
| A simplified homogenization model applied to viscoelastic behavior of cortical bone at ultrasonic frequencies | Journal of Biomechanics | Aróstica, R.; Aguilera, A.; Osses, A.; Minonzio, J. | 2022 | Ciudades Resilientes | 10.1016/j.jbiomech.2021.110868 | https://linkinghub.elsevier.com/retrieve/pii/S0021929021006242 | 110868 | Vol: 131 | 00219290 | Thomson Reuters ISI (SCIE) | English | Cortical bone is a complex multiscale medium and its study is of importance for clinical fracture prevention. In particular, cortical attenuation is known to be linked with shock energy absorption and ability to resist fracture. However, the links between cortical bone absorption and its multiscale structure are still not well understood. This work is about the use of homogenized tensors in order to characterize the viscoelastic behavior of cortical bone at ultrasonic frequencies, i.e., about 0.1 to 10 MHz. Such tensors are derived from the cell problem via two-scale homogenization theory for linear elastic and Kelvin–Voigt viscoelastic descriptions. The elliptic formulations obtained from the cell problems are implemented within the range of medically-observed porosities. Microstructure is assessed considering cubic cells with cylindrical inclusion and transverse isotropic assumption. A simplified model, adding one temporal parameter τ per phase, allows a good agreement with experimental data. The corresponding attenuation is proportional to the square of the frequency, in agreement with Kramer–Kronig relations. This development is proposed in the context of robust clinical inverse problem approaches using a restricted number of parameter. Two main properties for the material filling the pores are adjusted and discussed: absorption and shear contribution. Best agreement with experimental data is observed for material inside the pores being solid and highly attenuating. © 2021 Elsevier Ltd | |
| Boletín N° 3 Nueva Constitución chilena y cambio climático | Gobernanza climática de cuencas hidrográficas. Propuestas para la Nueva Constitución | Azocar, G.; Billi, M.; Borquez, R.; Alonso, C.; Alvarez, C.; Zambrano, M. | 2022 | https://www.cr2.cl/boletin-n-3-nueva-constitucion-chilena-y-cambio-climatico-gobernanza-climatica-de-cuencas-hidrograficas-propuestas-para-la-nueva-constitucion/ | 6 | cr2.cl | Spanish | La multiplicidad de causas e impactos del cambio climáti- co revelan la necesidad de contar con instrumentos de planificación y gestión que aborden su complejidad de manera integral, proponiendo intervenciones que se adecuen a las características particulares de cada territo- rio. En tal sentido, la toma de decisiones sobre este proble- ma debe considerar que el cambio climático depende de las interacciones entre procesos naturales y sociales que se producen y manifiestan diferenciadamente en distintas escalas territoriales (IPCC, 2021). Teniendo esto en consi- deración, nuestro diagnóstico indica que la actual gober- nanza climática en Chile se ha caracterizado por una serie de falencias (Billi et al, 2021a): a) la tendencia a adoptar medidas reactivas y de corto plazo, b) una distribución inequitativa de los impactos y costos provocados por el cambio climático, c) ineficaces mecanismos de participa- ción y de incorporación de saberes locales en la toma de decisiones, d) deficiente disponibilidad, calidad y acceso a evidencias científicas, e) fragmentación institucional asociada a una débil coordinación de la gestión del territo- rio, y f) una excesiva centralización de la toma de decisio- nes y baja consideración de las particularidades territoria- les y ecosistémicas sobre las cuales opera. Asumimos que para superar estas brechas uno de los principales desafíos de la nueva Constitución será incluir principios y orientaciones que sienten las bases para un nuevo modelo de gobernanza climática y ambiental en Chile (ver Billi et al., 2021b). Para ello, será necesaria la incorporación de nuevos instrumentos de gestión territo- rial que promuevan acciones para la mitigación y adapta- ción efectiva al cambio climático. En este texto propone- mos como uno de estos instrumentos la gobernanza climática de cuencas hidrográficas. |
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| Modeling the Ignition Risk: Analysis before and after Megafire on Maule Region, Chile | Applied Sciences | Azócar de la Cruz, G.; Alfaro, G.; Alonso, C.; Calvo, R.; Orellana, P. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.3390/app12189353 | https://www.mdpi.com/2076-3417/12/18/9353 | 9353 | Vol: 12 Issue: 18 | 2076-3417 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Wildland fires are a phenomenon of broad interest due to their relationship with climate change. The impacts of climate change are related to a greater frequency and intensity of wildland fires. In this context, megafires have become a phenomenon of particular concern. In this study, we develop a model of ignition risk. We use factors such as human activity, geographic, topographic, and land cover variables to develop a bagged decision tree model. The study area corresponds to the Maule region in Chile, a large zone with a Mediterranean climate. This area was affected by a megafire in 2017. After generating the model, we compared three interface zones, analyzing the scar and the occurrences of ignition during and after the megafire. For the construction of georeferenced data, we used the geographic information system QGIS. The results show a model with high fit goodness that can be replicated in other areas. Fewer ignitions are observed after the megafire, a high recovery of urban infrastructure, and a slow recovery of forest plantations. It is feasible to interpret that the lower number of ignitions observed in the 2019–2020 season is a consequence of the megafire scar. It is crucial to remember that the risk of ignition will increase as forest crops recover. Wildland fire management requires integrating this information into decision-making processes if we consider that the impacts of climate change persist in the area. |
| A combined microbial and biogeochemical dataset from high-latitude ecosystems with respect to methane cycle | Scientific Data | Barret, M.; Gandois, L.; Thalasso, F.; Martinez Cruz, K.; Sepulveda Jauregui, A.; Lavergne, C.; Teisserenc, R.; Aguilar, P.; Gerardo Nieto, O.; Etchebehere, C.; Martins Dellagnezze, B.; Bovio Winkler, P.; Fochesatto, G.; Tananaev, N.; Svenning, M.; Seppey, C.; Tveit, A.; Chamy, R.; Astorga España, M... | 2022 | Cambio de Uso de Suelo | 10.1038/s41597-022-01759-8 | https://www.nature.com/articles/s41597-022-01759-8 | 674 | Vol: 9 Issue: 1 | 2052-4463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract High latitudes are experiencing intense ecosystem changes with climate warming. The underlying methane (CH 4 ) cycling dynamics remain unresolved, despite its crucial climatic feedback. Atmospheric CH 4 emissions are heterogeneous, resulting from local geochemical drivers, global climatic factors, and microbial production/consumption balance. Holistic studies are mandatory to capture CH 4 cycling complexity. Here, we report a large set of integrated microbial and biogeochemical data from 387 samples, using a concerted sampling strategy and experimental protocols. The study followed international standards to ensure inter-comparisons of data amongst three high-latitude regions: Alaska, Siberia, and Patagonia. The dataset encompasses different representative environmental features (e.g. lake, wetland, tundra, forest soil) of these high-latitude sites and their respective heterogeneity (e.g. characteristic microtopographic patterns). The data included physicochemical parameters, greenhouse gas concentrations and emissions, organic matter characterization, trace elements and nutrients, isotopes, microbial quantification and composition. This dataset addresses the need for a robust physicochemical framework to conduct and contextualize future research on the interactions between climate change, biogeochemical cycles and microbial communities at high-latitudes. |
| Comment on: “The impact of a lack of government strategies for sustainable water management and land use planning on the hydrology of water bodies: lessons learned from the disappearance of the Aculeo Lagoon in central Chile” by Valdés-Pineda et al. 2022 in Sustainability, 14(1), 413 | Regional Environmental Change | Barría, P.; Ocampo-Melgar, A.; Chadwick, C.; Galleguillos, M.; Garreaud, R.; Díaz-Vasconcellos, R.; Poblete, D.; Rubio-Álvarez, E. | 2022 | Agua y Extremos; Cambio de Uso de Suelo | 10.1007/s10113-022-01991-3 | https://link.springer.com/10.1007/s10113-022-01991-3 | 131 | Vol: 22 Issue: 4 | 1436-3798, 1436-378X | Thomson Reuters ISI (SCIE; SSCI) | English | Valdés-Pineda et al. (Sustainability 14:413, 2022) present data for changes in climate, socio-economic, and land use and land cover (LULC) from diverse sources, concluding that the main causes for the desiccation of the Aculeo Lake were the river deviations and aquifer pumping, along with the impact of reduced precipitation. Based on that, they infer that the previous study of Barría et al. (Reg Environ Change 21:1–5, 2021a), which concluded that the impact of the decade-long drought was ten times larger than the increase of human extractions on the lake desiccation lacks scientific validity. We disagree with the conclusions from Valdés-Pineda et al. (Sustainability 14:413, 2022) and document that their article uses fragmentary information of a complex system, misinterprets of our results, and fails to present a reliable attribution methodology. We show that the hypothesis that the disappearance of Aculeo Lake was largely due to local anthropogenic uses is unsupported. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. | |
| Reestatización del agua potable y resiliencia neoliberal en Uruguay | urbe. Revista Brasileira de Gestão Urbana | Bascans, M.; Nicolas-Artero, C.; Gautreau, P.; Santos, C. | 2022 | Agua y Extremos | 10.1590/2175-3369.014.e20210133 | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2175-33692022000100212&tlng=es | e20210133 | Vol: 14 | 2175-3369 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | Spanish | Resumen El artículo discute sobre la neoliberalización de la naturaleza a partir del estudio de la reestatización de los servicios de distribución del agua potable y saneamiento en Uruguay durante el gobierno progresista del Frente Amplio. Se propone el concepto de “resiliencia neoliberal” para entender la reproducción de una lógica neoliberal en la gestión de estos servicios a pesar del reconocimiento del derecho humano al agua en la Constitución del país. A partir de una metodología cualitativa y cuantitativa, se reconstruye el proceso de privatización de los servicios hídricos y sus repercusiones sociales. Se identifican cuatro procesos que frenan la vuelta a servicios públicos y estatales: la permanencia de concesiones con capitales privados, la fragilización del sistema de subsidios cruzados, la desmovilización de la oposición y la inserción en un modelo de desarrollo económico neoliberal. , Abstract The article discusses the neoliberalisation of nature based on the study of the re-establishment of drinking water and sanitation services in Uruguay during the progressive government of the Frente Amplio. The concept of neoliberal resilience is proposed to understand the reproduction of a neoliberal logic in the management of these services despite the recognition of the human right to water in the Constitution. Using a qualitative and quantitative methodology, we reconstruct the process of privatisation of drinking water services and its social repercussions. Four processes are identified that slow down the return to public and state services: the permanence of concessions with private capital, the weakening of the system of cross-subsidies, the demobilisation of the opposition and the insertion of a neoliberal economic development model. , Resumo O artigo discute a neoliberalização da natureza com base no estudo do restabelecimento dos serviços de distribuição de água potável e saneamento no Uruguai durante o governo progressista da Frente Ampla. O conceito de resiliência neoliberal é proposto para compreender a reprodução de uma lógica neoliberal na gestão destes serviços, apesar do reconhecimento do direito humano à água na Constituição. Utilizando uma metodologia qualitativa e quantitativa, reconstruímos o processo de privatização dos serviços de água potável e suas repercussões sociais. São identificados quatro processos que abrandam o regresso aos serviços públicos e estatais: a permanência das concessões com capital privado, o enfraquecimento do sistema de subsídios cruzados, a desmobilização da oposição e a inserção num modelo de desenvolvimento econômico neoliberal. |
| Sustainability as a meta-narrative: the semantics of global governance? A systems-theoretical and concept-historical analysis; [Sustentabilidad como metanarrativa: ¿La semántica de la gobernanza global? Un análisis con base en la teoría de sistemas e historia conceptual] | Economia y Politica | Billi, M.; Marchant, G.; Bustamante, G. | 2022 | 10.15691/07194714.2022.005 | https://economiaypolitica.cl/index.php/eyp/article/view/167 | 137-169 | Vol: 9 Issue: 1 | 0719-4714 | English | Sustainability has become a ubiquitous concept in modern society, but its inherent ambiguity makes it a source of enduring controversy. While the mainstream narrative has striven to make it the fundamental telos of all human activities, counter-narrative accounts have tended to treat it as an empty, rhetorical catchword potentially used to justify imperialism. Not siding with either of these interpretations, this manuscript delves into how sustainability is, becomes, and endures as a concept, in addition to the performative effects it engenders in modern society. In particular, we argue that sustainability has functioned as a semantic horizon and meta-narrative that allowed modern governance to emerge and become the new global rationality. The paper takes an analytical approach based on conceptual history and sociology, observing concepts as webs of meanings in relation to latent social structures. On this basis, the paper provides a conceptual-historical reconstruction of the emergence, core meaning and communicative performance of sustainability semantics, followed by a reflection on its relation to governance. The manuscript concludes, first, that sustainability emerges as a way to overcome the communications paradox involved in the reciprocal interdependence between society and its environment. Second, that the current communicational success of sustainability semantics derives from its ability to combine flexibility and coherence across the cognitive and normative dimensions. And third, that this ability makes sustainability a common horizon of possibility (of meaning), in turn granting legitimacy and coherence to an emerging governance regime coordinating global efforts at steering and governing the interaction between society and its environment. © 2022 Universidad Adolfo Ibanez. All rights reserved. | |||
| Learning from crises? The long and winding road of the salmon industry in Chiloé Island, Chile | Marine Policy | Billi, M.; Mascareño, A.; Henríquez, P.; Rodríguez, I.; Padilla, F.; Ruz, G. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.marpol.2022.105069 | https://linkinghub.elsevier.com/retrieve/pii/S0308597X22001166 | 105069 | Vol: 140 | 0308-597X | Thomson Reuters ISI (SSCI) | English | The rapid development of salmon aquaculture worldwide and the growing criticism of the activity in recent decades have raised doubts about the capacity of the sector to learn from its own crises. In this article, we assess the discursive, behavioral and outcome performance dimensions of the industry to identify actual learning and lessons to be learned. We focus on the case of Chiloé Island, Chile, a global center of salmon production since 1990 that has gone through two severe crises in the last 15 years (2007–2009 ISAV crisis and 2016 red tide crisis). On the basis of a multi-method approach combining qualitative analysis of interviews and statistical data analysis, we observe that the industry has discursively learned the relevance of both self-regulation and the well-being of communities. However, at the behavioral and outcome performance levels, the data show a highly heterogeneous conduct that questions the ability of the sector as a whole to learn from crises. We conclude that detrimental effects for ecosystems and society will increase if learning remains at the level of discourses. Without significant changes in operational practices and market performance there are no real perspectives for the sustainability of the industry. This intensifies when considering the uneven responses to governance mechanisms. The sector needs to adapt its factual performance to sustainable goals and reflexively monitor this process. The first step for achieving this is to produce reliable data to make evidence-based decisions that align the operational dynamics of the entire sector with a more sustainable trajectory in the near future, as well as advancing towards hybrid and more reflexive governance arrangements. © 2022 Elsevier Ltd | |
| Editorial: Discussing structural, systemic and enabling approaches to socio-environmental transformations: Stimulating an interdisciplinary and plural debate within the social sciences | Frontiers in Sociology | Billi, M.; Zurbriggen, C.; Morchain, D. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.3389/fsoc.2022.968018 | https://www.frontiersin.org/articles/10.3389/fsoc.2022.968018/full | 968018 | Vol: 7 | 2297-7775 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | |
| Antarctic Polyester Hydrolases Degrade Aliphatic and Aromatic Polyesters at Moderate Temperatures | Applied and Environmental Microbiology | Blázquez-Sánchez, P.; Engelberger, F.; Cifuentes-Anticevic, J.; Sonnendecker, C.; Griñén, A.; Reyes, J.; Díez, B.; Guixé, V.; Richter, P.; Zimmermann, W.; Ramírez-Sarmiento, C. | 2022 | Zonas Costeras | 10.1128/AEM.01842-21 | https://journals.asm.org/doi/10.1128/AEM.01842-21 | e01842-21 | Vol: 88 Issue: 1 | 0099-2240, 1098-5336 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | A myriad of consumer products contains polyethylene terephthalate (PET), a plastic that has accumulated as waste in the environment due to its long-term stability and poor waste management. One promising solution is the enzymatic biodegradation of PET, with most known enzymes only catalyzing this process at high temperatures. , ABSTRACT Polyethylene terephthalate (PET) is one of the most widely used synthetic plastics in the packaging industry, and consequently has become one of the main components of plastic waste found in the environment. However, several microorganisms have been described to encode enzymes that catalyze the depolymerization of PET. While most known PET hydrolases are thermophilic and require reaction temperatures between 60°C and 70°C for an efficient hydrolysis of PET, a partial hydrolysis of amorphous PET at lower temperatures by the polyester hydrolase Is PETase from the mesophilic bacterium Ideonella sakaiensis has also been reported. We show that polyester hydrolases from the Antarctic bacteria Moraxella sp. strain TA144 (Mors1) and Oleispira antarctica RB-8 (OaCut) were able to hydrolyze the aliphatic polyester polycaprolactone as well as the aromatic polyester PET at a reaction temperature of 25°C. Mors1 caused a weight loss of amorphous PET films and thus constitutes a PET-degrading psychrophilic enzyme. Comparative modeling of Mors1 showed that the amino acid composition of its active site resembled both thermophilic and mesophilic PET hydrolases. Lastly, bioinformatic analysis of Antarctic metagenomic samples demonstrated that members of the Moraxellaceae family carry candidate genes coding for further potential psychrophilic PET hydrolases. IMPORTANCE A myriad of consumer products contains polyethylene terephthalate (PET), a plastic that has accumulated as waste in the environment due to its long-term stability and poor waste management. One promising solution is the enzymatic biodegradation of PET, with most known enzymes only catalyzing this process at high temperatures. Here, we bioinformatically identified and biochemically characterized an enzyme from an Antarctic organism that degrades PET at 25°C with similar efficiency to the few PET-degrading enzymes active at moderate temperatures. Reasoning that Antarctica harbors other PET-degrading enzymes, we analyzed available data from Antarctic metagenomic samples and successfully identified other potential enzymes. Our findings contribute to increasing the repertoire of known PET-degrading enzymes that are currently being considered as biocatalysts for the biological recycling of plastic waste. |
| Temperature and moisture transport during atmospheric blocking patterns around the Antarctic Peninsula | Weather and Climate Extremes | Bozkurt, D.; Marín, J.; Barrett, B. | 2022 | Zonas Costeras | 10.1016/j.wace.2022.100506 | https://linkinghub.elsevier.com/retrieve/pii/S2212094722000858 | 100506 | Vol: 38 | 22120947 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | We assess temperature and moisture transport in and around the Antarctic Peninsula (AP) associated with atmospheric blocking over two domains, one located to the west (150–90°W, 50–70°S, Western AP (WAP)) and the other over and to the east (90–30°W, 50–70°S, Eastern AP (EAP)) of the AP. We make use of surface meteorological observations, ERA5 reanalysis data, and a state-of-the-art atmospheric river (AR) database. Observed temperature anomalies indicate that the WAP and EAP blocking patterns are characterized by significant cold and warm anomalies over the AP, respectively, particularly in austral autumn, winter and spring. Consistent with these changes, cold anomalies depicted by ERA5 are associated with the transport of cold and dry air from the Antarctic continent by southerly and southeasterly flow over the eastern flank of the WAP blocking. ERA5 results highlight the importance of blocking days over the EAP domain (largely centered over the Drake Passage) to the occurrence of warm events associated with northerly and northwesterly warm air transport. Significant increases in integrated vapor transport (IVT) and AR frequency are also evident during the EAP blocking, particularly on the windward side of the AP. During the most extreme blocking days in this domain, there exist significant increases in latent and sensible heat fluxes on the windward side of the AP and the Larsen C Ice Shelf, respectively, indicating the contribution of foehn events to warm anomalies, especially in austral autumn and winter. The co-occurrences between landfalling ARs and blocking are found to amplify foehn effect due to higher IVT and associated latent heat condensation compared to blocking days without ARs. We conclude that blocking patterns are important to understand the occurrence of extremely warm events and landfalling ARs in the AP and their potential impacts on the surface cryospheric processes. © 2022 The Author(s) |
| Global wood anatomical perspective on the onset of the Late Antique Little Ice Age (LALIA) in the mid-6th century CE | Science Bulletin | Büntgen, U.; Crivellaro, A.; Arseneault, D.; Baillie, M.; Barclay, D.; Bernabei, M.; Bontadi, J.; Boswijk, G.; Brown, D.; Christie, D.; Churakova, O.; Cook, E.; D’Arrigo, R.; Davi, N.; Esper, J.; Fonti, P.; Greaves, C.; Hantemirov, R.; Hughes, M.; Kirdyanov, A.; Krusic, P.; Le Quesne, C.; Ljungqvist... | 2022 | Agua y Extremos | 10.1016/j.scib.2022.10.019 | https://linkinghub.elsevier.com/retrieve/pii/S2095927322004790 | 2336-2344 | Vol: 67 Issue: 22 | 2095-9273 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Linked to major volcanic eruptions around 536 and 540 CE, the onset of the Late Antique Little Ice Age has been described as the coldest period of the past two millennia. The exact timing and spatial extent of this exceptional cold phase are, however, still under debate because of the limited resolution and geographical distribution of the available proxy archives. Here, we use 106 wood anatomical thin sections from 23 forest sites and 20 tree species in both hemispheres to search for cell-level fingerprints of ephemeral summer cooling between 530 and 550 CE. After cross-dating and double-staining, we identified 89 Blue Rings (lack of cell wall lignification), nine Frost Rings (cell deformation and collapse), and 93 Light Rings (reduced cell wall thickening) in the Northern Hemisphere. Our network reveals evidence for the strongest temperature depression between mid-July and early-August 536 CE across North America and Eurasia, whereas more localised cold spells occurred in the summers of 532, 540–43, and 548 CE. The lack of anatomical signatures in the austral trees suggests limited incursion of stratospheric volcanic aerosol into the Southern Hemisphere extra-tropics, that any forcing was mitigated by atmosphere-ocean dynamical responses and/or concentrated outside the growing season, or a combination of factors. Our findings demonstrate the advantage of wood anatomical investigations over traditional dendrochronological measurements, provide a benchmark for Earth system models, support cross-disciplinary studies into the entanglements of climate and history, and question the relevance of global climate averages. © 2022 Science China Press |
| Energy poverty effects on policy-based PM2.5 emissions mitigation in southern and central Chile | Energy Policy | Calvo, R.; Álamos, N.; Huneeus, N.; O'Ryan, R. | 2022 | Ciudades Resilientes | 10.1016/j.enpol.2021.112762 | https://linkinghub.elsevier.com/retrieve/pii/S0301421521006285 | 112762 | Vol: 161 | 03014215 | Thomson Reuters ISI (SCIE; SSCI) | English | Residential firewood burning is the main source of PM2.5 emissions in southern and central Chile. In Chile, approximately 4000 premature deaths are observed each year due to air pollution. Mitigation policies aim to reduce dwellings' energy demand and foster cleaner but more expensive energy sources. Pre-existing energy poverty conditions are often overlooked in these policies, even though they can negatively affect the adoption of these measures. This article uses southern and central Chile as a case study to assess quantitatively different policy scenarios of PM2.5 emissions between 2017 and 2050, considering energy poverty-related effects. Results show that PM2.5 emissions will grow 16% over time under a business as usual scenario. If thermal improvement and stove/heater replacements are implemented, PM2.5 reductions depend on the scale of the policy: a 5%–6% reduction of total southern and central Chile PM2.5 emissions if only cities with Atmospheric Decontamination Plans are included; a 54%–56% reduction of PM2.5 emissions if these policies include other growing cities. Our study shows that the energy poverty effect potentially reduces the effectiveness of these measures in 25%. Consequently, if no anticipatory measures are taken, Chile's energy transition goals could be hindered and the effectiveness of mitigation policies to improve air quality significantly reduced. | |
| A comparison of mixed logit and latent class models to estimate market segments for seafood faced with ocean acidification | Aquaculture Economics & Management | Campos-Requena, N.; Vásquez-Lavin, F.; Fernández, F.; Barrientos, M.; Gelcich, S.; Oliva, R. | 2022 | Cambio de Uso de Suelo | 10.1080/13657305.2022.2100005 | https://www.tandfonline.com/doi/full/10.1080/13657305.2022.2100005 | 1-33 | Vol: 27 | 1365-7305, 1551-8663 | Thomson Reuters ISI (SCIE) | English | This study uses a choice experiment to characterize market segments (consumer preferences heterogeneity) based on three attributes of seafood (mussels) that are affected by ocean acidification: shell appearance, meat color, and nutritional composition. Using a sample of 1,257 individuals from two main cities in Chile, we estimate both the Mixed Logit model and the Latent Class model. We use the individual-specific posterior (ISP) parameters’ distribution to categorize consumers’ heterogeneity based on the signs and intensity (i.e., like or dislike dimension) of these ISPs. We compare the pattern of preferences and whether people are classified within the same preference pattern in both models. In general, we observed that the models identify a different number of segments with various patterns of preferences. Moreover, the models classify the same people into different groups. Since the segmentation is sensitive to the chosen model, we discuss strengths, inconsistencies, biases, and best practices regarding methodological approaches to establishing market segments in choice experiments and future ocean acidification conditions. © 2022 Taylor & Francis Group, LLC. | |
| Local agendas for tackling climate change: Comparative analysis of the Municipalities of Concepción and Caleta Tortel in Chile; [Agendas locales para enfrentar el cambio climático: Análisis comparado de la Municipalidad de Concepción y la Municipalidad de Caleta Tortel en Chile] | Revista Chilena de Derecho y Ciencia Politica | Cariaga, V. | 2022 | 10.7770/rchdcp-V13N1-art2696 | https://derechoycienciapolitica.uct.cl/index.php/RDCP/article/view/57 | 208-238 | Vol: 13 Issue: 1 | 07189389 | Scopus | Spanish | The Network of Municipalities in the face of Climate Change has turned out to be a space where municipalities can seek support and guidance, to work on mitigation and adaptation areas of their locality. In this sense, the proposal of a climate change program composed of nine thematic areas has been of primary concern, considering that not all municipalities work the program in its entirety. Against this, only two municipalities are prominent for developing the nine thematic areas: the Municipality of Concepción and the Municipality of Caleta Tortel. The research results in the fact that the political and the technical factors turn out to be the common point of both municipalities and that these can influence the number of thematic areas reached. © 2022, Catholic University of Temuco Faculty of Law Economics and Administrative Sciences. All rights reserved. | ||
| Testing the Model Efficiency of HYDRUS 2D/3D Under Desert Conditions for Water Content and Pore Electrical Conductivity: a Case Study in an Olive Orchard | Journal of Soil Science and Plant Nutrition | Carlos, F.; Cristian, K.; Marco, G.; Mauricio, G.; Humberto, A.; de Miranda Jarbas, H.; Oscar, S. | 2022 | Cambio de Uso de Suelo | 10.1007/s42729-022-00777-0 | https://link.springer.com/10.1007/s42729-022-00777-0 | 1859-1872 | Vol: 22 Issue: 2 | 0718-9508, 0718-9516 | Thomson Reuters ISI (SCIE) | English | The water crisis is a concern for Chilean agriculture. Testing new methods based on computer simulations is urgent to optimize irrigation. This study aimed to assess the model efficiency of HYDRUS 2D/3D simulations of volumetric water content (θ) and pore electrical conductivity (ECp) in an olive tree variety Kalamata under desert conditions. The model efficiency was assessed by comparing model simulations against observations of θ and ECp in five frequency domain reflectometry (FDR) sensors installed in the soil profile. Model simulations were improved by calibration using PEST software. Global sensitivity analysis was performed before calibration, analyzing both θ and ECp model outputs. Outcomes of sensitivity analysis indicate that the surface area associated with transpiration (ST) and the slope of the stress response function (s) are relevant parameters for θ and ECp. Both parameters were calibrated along with the saturated water content (θs) and pore size distribution (n) parameters of the second material. Calibration improved HYDRUS 2D/3D simulations for θ but not substantially for ECp. However, the Nash–Sutcliffe and the root mean square error (RMSE) are comparable with previous research for both variables. Furthermore, the s parameter decreases after calibration, indicating that Kalamata variety is tolerant to salt, which is in line with previous research. HYDRUS 2D/3D represents the θ variation in time and space with acceptable precision for olive trees under desert conditions. Additionally, subsequent studies should focus on the value of s, which is variety dependent, and ST, which requires the actual root volume. © 2022, The Author(s) under exclusive licence to Sociedad Chilena de la Ciencia del Suelo. | |
| ¿Reconocimiento de los pueblos indígenas y sus aportes en la acción climática? Un análisis del informe del IPCC sobre Impactos, Adaptación y Vulnerabilidad | Carmona, R.; Petrasek, J.; Sambo, D.; Bhadra, T.; Abraham, G.; Thorsell, S. | 2022 | https://www.cr2.cl/36100-2/ | 9 | cr2.cl | ||||||||
| From mobilization to the convention: Dynamics and strategies of socio-environmental organizations in the Chilean constituent process; [DE LA MOVILIZACIÓN A LA CONVENCIÓN: DINÁMICAS Y ESTRATEGIAS DE LAS ORGANIZACIONES SOCIOAMBIENTALES EN EL PROCESO CONSTITUYENTE CHILENO] | Universum | Carrasco, S.; Abad, P.; Cuevas, C.; Cariaga, V.; Mansilla, P.; Maillet, A. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.4067/S0718-23762022000200667 | https://doi.org/10.4067/S0718-23762022000200667 | 667-693 | Vol: 37 Issue: 2 | 0716-498X | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | Spanish | The social outburst in Chile generated a relevant milestone in the country's political system, since it catalyzed a process of constitutional change. In this context, the research analyzes the role of socio-territorial actors in the positioning of environmental demands in the constitutional process. In addition, the configuration and strategies of environmental organizations are established. To do this, the article analyzes an intentional sample of socio-environmental organizations deployed throughout the national territory. In the same way, a theoretical perspective is developed on the political strategies of social-environmental organizations and establishes a mixed methodological strategy, combining quantitative and qualitative techniques. The results show that socio-environmental organizations maintain certain common elements regarding the environmental demands they pursue, yet differ in the use of different strategies to influence the constituent process, both insider and outsider. The study contributes to the discussion on environmental mobilization in Chile, moving beyond the case studies, which are the dominant perspectives in this type of research; and at the same time, it portrays an ongoing political process, thus contributing to the current public discussion. © 2022 Universidad de Talca. All rights reserved. |
| Worldwide Signature of the 2022 Tonga Volcanic Tsunami | Geophysical Research Letters | Carvajal, M.; Sepúlveda, I.; Gubler, A.; Garreaud, R. | 2022 | Agua y Extremos | 10.1029/2022GL098153 | https://onlinelibrary.wiley.com/doi/10.1029/2022GL098153 | arte2022GL098153 | Vol: 49 Issue: 6 | 0094-8276, 1944-8007 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | The eruption of the Hunga Tonga-Hunga Ha'apai Volcano in January 2022 in the southwest Pacific islands of Tonga triggered a tsunami that was detected beyond the Pacific basin. Here we show its spatiotemporal signature as revealed by hundreds of publicly available coastal tide gauge records from around the world. The Tonga tsunami was characterized by a uniformly small leading wave that arrived earlier than theoretically expected for a tsunami wave freely propagating away from the volcano. In contrast, the largest waves, of up to +3 m high, were concentrated in the Pacific and their timing agrees well with tsunami propagation times from the volcano. While the leading waves were caused by a previously reported fast-moving atmospheric pressure pulse generated in the volcanic explosion, the large waves observed later in the Pacific were likely originated in the vicinity of the volcano although its generation mechanism(s) cannot be identified by the tide gauge data alone. © 2022. American Geophysical Union. All Rights Reserved. |
| PAPILA dataset: a regional emission inventory of reactive gases for South America based on the combination of local and global information | Earth System Science Data | Castesana, P.; Diaz Resquin, M.; Huneeus, N.; Puliafito, E.; Darras, S.; Gómez, D.; Granier, C.; Osses Alvarado, M.; Rojas, N.; Dawidowski, L. | 2022 | Ciudades Resilientes | 10.5194/essd-14-271-2022 | https://essd.copernicus.org/articles/14/271/2022/ | 271-293 | Vol: 14 Issue: 1 | 1866-3516 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract. The multidisciplinary project Prediction of Air Pollution in Latin America and the Caribbean (PAPILA) is dedicated to the development and implementation of an air quality analysis and forecasting system to assess pollution impacts on human health and economy. In this context, a comprehensive emission inventory for South America was developed on the basis of the existing data on the global dataset CAMS-GLOB-ANT v4.1 (developed by joining CEDS trends and EDGAR v4.3.2 historical data), enriching it with data derived from locally available emission inventories for Argentina, Chile, and Colombia. This work presents the results of the first joint effort of South American researchers and European colleagues to generate regional maps of emissions, together with a methodological approach to continue incorporating information into future versions of the dataset. This version of the PAPILA dataset includes CO, NOx, NMVOCs, NH3, and SO2 annual emissions from anthropogenic sources for the period 2014–2016, with a spatial resolution of 0.1∘ × 0.1∘ over a domain that covers 32–120∘ W and 34∘ N–58∘ S. The PAPILA dataset is presented as netCDF4 files and is available in an open-access data repository under a CC-BY 4 license: https://doi.org/10.17632/btf2mz4fhf.3 (Castesana et al., 2021). A comparative assessment of PAPILA–CAMS datasets was carried out for (i) the South American region, (ii) the countries with local data (Argentina, Colombia, and Chile), and (iii) downscaled emission maps for urban domains with different environmental and anthropogenic factors. Relevant differences were found at both country and urban levels for all the compounds analyzed. Among them, we found that when comparing PAPILA total emissions versus CAMS datasets at the national level, higher levels of NOx and considerably lower levels of the other species were obtained for Argentina, higher levels of SO2 and lower levels of CO and NOx for Colombia, and considerably higher levels of CO, NMVOCs, and SO2 for Chile. These discrepancies are mainly related to the representativeness of local practices in the local emission estimates, to the improvements made in the spatial distribution of the locally estimated emissions, or to both. Both datasets were evaluated against surface concentrations of CO and NOx by using them as input data to the WRF-Chem model for one of the analyzed domains, the metropolitan area of Buenos Aires, for summer and winter of 2015. PAPILA-based modeling results had a smaller bias for CO and NOx concentrations in winter while CAMS-based results for the same period tended to deliver an underestimation of these concentrations. Both inventories exhibited similar performances for CO in summer, while the PAPILA simulation outperformed CAMS for NOx concentrations. These results highlight the importance of refining global inventories with local data to obtain accurate results with high-resolution air quality models. |
| The complex Andes region needs improved efforts to face climate extremes | Elementa: Science of the Anthropocene | Cazorla, M.; Gallardo, L.; Jimenez, R. | 2022 | Ciudades Resilientes | 10.1525/elementa.2022.00092 | https://online.ucpress.edu/elementa/article/10/1/00092/194534/The-complex-Andes-region-needs-improved-efforts-to | 00092 | Vol: 10 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The steep slopes, highlands, and valleys of the Andes mountain chain are inhabited throughout its formidable length. This unique characteristic does not repeat in any other mountain region. The Andes shape weather and climate in South America. However, proper understanding of atmospheric phenomena influenced by a daunting altitudinal gradient is still behind what is needed to produce detailed and consistent climate projections. Despite significant advances, global models misrepresent key precipitation and circulation processes that are influenced by complex topography. Along with a lack of coordinated observations, the result is limited information to design preparedness measures, particularly to face extreme climate events. Of equal concern is the issue of air quality in densely urbanized countries that face decarbonization challenges and share a legacy of social inequity and political unrest. The complexity of the Andes region magnifies risks within all nations that share their influence. Thus, urgent action is needed to improve climate and air quality assessments with the direct purpose of strengthening policy-making processes. |
| Callampas of disaster: negotiations and struggles for the commons under forestry hegemony in Chile | Community Development Journal | Cid-Aguayo, B.; Krstulovic-Matus, J.; Carrasco Henríquez, N.; Mella-Moraga, V.; Oñate Vargas, D. | 2022 | Zonas Costeras | 10.1093/cdj/bsac030 | https://academic.oup.com/cdj/advance-article/doi/10.1093/cdj/bsac030/6762889 | bsac030 | Vol: 58 | 0010-3802, 1468-2656 | Thomson Reuters ISI (SSCI) | English | The massive planting of exotic species under the so-called forestry model has dramatically transformed the landscapes of south-central Chile, replacing diverse agricultural, livestock and forest landscapes with forest monocultures, which are highly water-consuming and prone to massive fires. This has meant a productive simplification, and peasant communities have been displaced and stripped of their traditional ways of life. However, in this landscape of disaster, biotic communities of fungi have flourished, and with them human communities of collectors have learned to sustain themselves in a monocultural and privatized scenario. This paper is based on a multi-local ethnographic approach, built upon 26 semi-structured interviews, participant observation, social mapping, creating a calendar and a trend line. The text documents the processes of two communities affected by massive fires which have developed organization, agencies and practices. Mushrooms (callampas in Chilean Spanish) are claimed as a common good derived from the forestry model, claiming access to their use and usufruct of land belonging to forestry companies. They have also developed local governance systems for the care and better use of this new resource for common use. Forestry companies, for their part, try to subsume these practices in their territorial governance processes, disputing these commons’ meaning and purpose. Both cases contribute to empirically address the central thesis of this article, according to which communalization exercises within contexts of capitalist expansion constitute responses of survival, resistance and adaptation in landscapes transformed and devastated by extractivist industries. | |
| Central tropical Pacific convection drives extreme high temperatures and surface melt on the Larsen C Ice Shelf, Antarctic Peninsula | Nature Communications | Clem, K.; Bozkurt, D.; Kennett, D.; King, J.; Turner, J. | 2022 | Zonas Costeras | 10.1038/s41467-022-31119-4 | https://www.nature.com/articles/s41467-022-31119-4 | 3906 | Vol: 13 Issue: 1 | 2041-1723 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract Northern sections of the Larsen Ice Shelf, eastern Antarctic Peninsula (AP) have experienced dramatic break-up and collapse since the early 1990s due to strong summertime surface melt, linked to strengthened circumpolar westerly winds. Here we show that extreme summertime surface melt and record-high temperature events over the eastern AP and Larsen C Ice Shelf are triggered by deep convection in the central tropical Pacific (CPAC), which produces an elongated cyclonic anomaly across the South Pacific coupled with a strong high pressure anomaly over Drake Passage. Together these atmospheric circulation anomalies transport very warm and moist air to the southwest AP, often in the form of “atmospheric rivers”, producing strong foehn warming and surface melt on the eastern AP and Larsen C Ice Shelf. Therefore, variability in CPAC convection, in addition to the circumpolar westerlies, is a key driver of AP surface mass balance and the occurrence of extreme high temperatures. |
| High ENSO sensitivity in tree rings from a northern population of Polylepis tarapacana in the Peruvian Andes | Dendrochronologia | Crispín-DelaCruz, D.; Morales, M.; Andreu-Hayles, L.; Christie, D.; Guerra, A.; Requena-Rojas, E. | 2022 | Agua y Extremos | 10.1016/j.dendro.2021.125902 | https://linkinghub.elsevier.com/retrieve/pii/S1125786521000989 | 125902 | Vol: 71 | 1125-7865 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Polylepis tarapacana is the highest-elevation tree species worldwide growing between 4000 and 5000 m a.s.l. along the South American Altiplano. P. tarapacana is adapted to live in harsh conditions and has been widely used for drought and precipitation tree-ring based reconstructions. Here, we present a 400-year tree-ring width (TRW) chronology located in southern Peru (17ºS; 69ºW) at the northernmost limit of P. tarapacana tree species distribution. The objectives of this study are to assess tree growth sensitivity of a northern P. tarapacana population to (1) precipitation, temperature and El Niño Southern Oscillation (ENSO) variability; (2) to compare its growth variability and ENSO sensitivity with southern P. tarapacana forests. Our results showed that this TRW record is highly sensitive to the prior summer season (Nov-Jan) precipitation (i.e. positive correlation) when the South American Summer Monsoon (SASM) reaches its maximum intensity in this region. We also found a positive relationship with current year temperature that suggests that radial growth may be enhanced by warm, less cloudy, conditions during the year of formation. A strong positive relationship was found between el Niño 3.4 and tree growth variability during the current growing season, but negative during the previous growth period. Growth variability in our northern study site was in agreement with other populations that represent almost the full range of P. tarapacana latitudinal distribution (~ 18ºS to 23ºS). Towards the south of the P. tarapacana TRW network there was a decrease in the strength of the agreement of growth variability with our site,with the exception of higher correlation with the two southeastern sites. Similarly, the TRW chronologies recorded higher sensitivity to ENSO influences in the north and southeastern locations, which are wetter, than the drier southwestern sites. These patterns hold for the entire period, as well as for periods of high and low ENSO activity. Overall, P. tarapacana tree growth at the north of its distribution is mostly influenced by prior year moisture availability and current year temperature that are linked to large-scale climate patterns such as the SASM and ENSO, respectively. |
| Well-to-wheel emissions and abatement strategies for passenger vehicles in two Latin American cities | Environmental Science and Pollution Research | Cuéllar-Álvarez, Y.; Clappier, A.; Osses, M.; Thunis, P.; Belalcázar-Cerón, L. | 2022 | Ciudades Resilientes | 10.1007/s11356-022-20885-9 | https://link.springer.com/10.1007/s11356-022-20885-9 | 72074-72085 | Vol: 29 | 0944-1344, 1614-7499 | Thomson Reuters ISI (SCIE) | English | More stringent standards for engines and fuels are progressively implemented as alternatives to reduce on-road vehicle emissions. While electric vehicles appear as a perfect alternative since their engines do not emit pollutants, wear and dust resuspension (W&R) and indirect emissions associated with electricity production remain significant sources of pollution. This work compares well-to-wheel emissions (WTW) and abatement strategies for various types of passenger vehicles in Bogotá and Santiago for different pollutants (CO, PM2.5, SO2, and NOx) and greenhouse gases like CO2 equivalent (CO2-Eq). Results show that WTW baseline emissions are more extensive in Bogotá than in Santiago (i.e., 58 and 30% for PM2.5 and CO2-Eq), mainly due to the higher vehicle activity and older state of Bogotá’s fleet. We also evaluated extreme scenarios to assess the potential of a given vehicle technology or energy source to reduce emissions. We assessed, in particular, the replacement of all current vehicles by (1) conventional technologies with stricter emission standards and (2) battery electric vehicles powered with different energy resources. Our results indicate that replacing the current fleet with modern combustion technologies has a lower reduction potential than battery electric vehicles, but these reductions largely depend on the energy mix. Substitution by electric vehicles powered with electricity from renewable energies is the most efficient scenario in both cities. Finally, results also stress the importance of the resuspension of deposited road dust and brake and tire wear emissions in both cities as a crucial source of PM2.5, which must be better controlled. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. | |
| Impact of biomass burning and stratospheric intrusions in the remote South Pacific Ocean troposphere | Atmospheric Chemistry and Physics | Daskalakis, N.; Gallardo, L.; Kanakidou, M.; Nüß, J.; Menares, C.; Rondanelli, R.; Thompson, A.; Vrekoussis, M. | 2022 | Ciudades Resilientes; Zonas Costeras | 10.5194/acp-22-4075-2022 | https://acp.copernicus.org/articles/22/4075/2022/ | 4075-4099 | Vol: 22 Issue: 6 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract. The ozone mixing ratio spatiotemporal variability in the pristine South Pacific Ocean is studied, for the first time, using 21-year-long ozone (O3) records from the entire southern tropical and subtropical Pacific between 1994 and 2014. The analysis considered regional O3 vertical observations from ozonesondes, surface carbon monoxide (CO) observations from flasks, and three-dimensional chemistry-transport model simulations of the global troposphere. Two 21-year-long numerical simulations, with and without biomass burning emissions, were performed to disentangle the importance of biomass burning relative to stratospheric intrusions for ambient ozone levels in the region. Tagged tracers of O3 from the stratosphere and CO from various biomass burning regions have been used to track the impact of these different regions on the southern tropical Pacific O3 and CO levels. Patterns have been analyzed based on atmospheric dynamics variability. Considering the interannual variability in the observations, the model can capture the observed ozone gradients in the troposphere with a positive bias of 7.5 % in the upper troposphere/lower stratosphere (UTLS) as well as near the surface. Remarkably, even the most pristine region of the global ocean is affected by distant biomass burning emissions by convective outflow through the mid and high troposphere and subsequent subsidence over the pristine oceanic region. Therefore, the biomass burning contribution to tropospheric CO levels maximizes in the UTLS. The Southeast Asian open fires have been identified as the major contributing source to CO from biomass burning in the tropical South Pacific, contributing on average for the study period about 8.5 and 13 ppbv of CO at Rapa Nui and Samoa, respectively, at an altitude of around 12 km during the burning season in the spring of the Southern Hemisphere. South America is the second-most important biomass burning source region that influences the study area. Its impact maximizes in the lower troposphere (6.5 ppbv for Rapa Nui and 3.8 ppbv for Samoa). All biomass burning sources contribute about 15–23 ppbv of CO at Rapa Nui and Samoa and account for about 25 % of the total CO in the entire troposphere of the tropical and subtropical South Pacific. This impact is also seen on tropospheric O3, to which biomass burning O3 precursor emissions contribute only a few ppbv during the burning period, while the stratosphere–troposphere exchange is the most important source of O3 for the mid troposphere of the South Pacific Ocean, contributing about 15–20 ppbv in the subtropics. |
| Enhanced nitrogen and carbon removal in natural seawater by electrochemical enrichment in a bioelectrochemical reactor | Journal of Environmental Management | De La Fuente, M.; De la Iglesia, R.; Farías, L.; Glasner, B.; Torres-Rojas, F.; Muñoz, D.; Daims, H.; Lukumbuzya, M.; Vargas, I. | 2022 | Zonas Costeras | 10.1016/j.jenvman.2022.116294 | https://linkinghub.elsevier.com/retrieve/pii/S0301479722018679 | 116294 | Vol: 323 | 03014797 | Thomson Reuters ISI (SCIE) | English | Municipal and industrial wastewater discharges in coastal and marine environments are of major concern due to their high carbon and nitrogen loads and the resulted phenomenon of eutrophication. Bioelectrochemical reactors (BERs) for simultaneous nitrogen and carbon removal have gained attention owing to their cost efficiency and versatility, as well as the possibility of electrochemical enrich specific groups. This study presented a scalable two-chamber BERs using graphite granules as electrode material. BERs were inoculated and operated for 37 days using natural seawater with high concentrations of ammonium and acetate. The BERs demonstrated a maximum current density of 0.9 A m−3 and removal rates of 7.5 mg NH4+-N L−1 d−1 and 99.5 mg L−1 d−1 for total organic carbon (TOC). Removals observed for NH4+-N and TOC were 96.2% and 68.7%, respectively. The results of nutrient removal (i.e., ammonium, nitrate, nitrite and TOC) and microbial characterization (i.e., next-generation sequencing of the 16S rRNA gene and fluorescence in situ hybridization) showed that BERs operated with a poised cathode at −260 mV (vs. Ag/AgCl) significantly enriched nitrifying microorganisms in the anode and denitrifying microorganisms and planctomycetes in the cathode. Interestingly, the electrochemical enrichment did not increase the total number of microorganisms in the formed biofilms but controlled their composition. Thus, this work shows the first successful attempt to electrochemically enrich marine nitrifying and denitrifying microorganisms and presents a technique to accelerate the start-up process of BERs to remove dissolved inorganic nitrogen and total organic carbon from seawater. © 2022 Elsevier Ltd | |
| The global spectrum of plant form and function: enhanced species-level trait dataset | Scientific Data | Díaz, S.; Kattge, J.; Cornelissen, J.; Wright, I.; Lavorel, S.; Dray, S.; Reu, B.; Kleyer, M.; Wirth, C.; Prentice, I.; Garnier, E.; Bönisch, G.; Westoby, M.; Poorter, H.; Reich, P.; Moles, A.; Dickie, J.; Zanne, A.; Chave, J.; Wright, S.; Sheremetiev, S.; Jactel, H.; Baraloto, C.; Cerabolini, B.; P... | 2022 | Cambio de Uso de Suelo | 10.1038/s41597-022-01774-9 | https://www.nature.com/articles/s41597-022-01774-9 | 755 | Vol: 9 Issue: 1 | 2052-4463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract Here we provide the ‘Global Spectrum of Plant Form and Function Dataset’, containing species mean values for six vascular plant traits. Together, these traits –plant height, stem specific density, leaf area, leaf mass per area, leaf nitrogen content per dry mass, and diaspore (seed or spore) mass – define the primary axes of variation in plant form and function. The dataset is based on ca. 1 million trait records received via the TRY database (representing ca. 2,500 original publications) and additional unpublished data. It provides 92,159 species mean values for the six traits, covering 46,047 species. The data are complemented by higher-level taxonomic classification and six categorical traits (woodiness, growth form, succulence, adaptation to terrestrial or aquatic habitats, nutrition type and leaf type). Data quality management is based on a probabilistic approach combined with comprehensive validation against expert knowledge and external information. Intense data acquisition and thorough quality control produced the largest and, to our knowledge, most accurate compilation of empirically observed vascular plant species mean traits to date. |
| Forest plantation subsidies: Impact evaluation of the Chilean case | Forest Policy and Economics | España, F.; Arriagada, R.; Melo, O.; Foster, W. | 2022 | Cambio de Uso de Suelo | 10.1016/j.forpol.2022.102696 | https://linkinghub.elsevier.com/retrieve/pii/S1389934122000089 | 102696 | Vol: 137 | 1389-9341 | Thomson Reuters ISI (SCIE; SSCI) | English | Over the past half century there has been a rapid expansion of the forestry sector in Chile. One hypothesis is that this growth was stimulated in major part by government-supported financial incentives to forestry plantations dating from the mid-1970s. Evaluating the effects of subsidies on plantations is of current policy interest due to the potential importance of forests as carbon sinks. This study evaluates the impact of subsidies on the establishment of forest plantations (under the specific law DL701) for the period between the years 1998 and 2013 using matching techniques in combination with Difference-in-Differences. Results show that government subsidies have had a statistically and economically significant positive impact on plantations, increasing the forested area of subsidy program participants by approximately 13% compared with the counterfactual scenario without such subsidies. © 2022 Elsevier B.V. | |
| Atmospheric rivers drive exceptional Saharan dust transport towards Europe | Atmospheric Research | Francis, D.; Fonseca, R.; Nelli, N.; Bozkurt, D.; Picard, G.; Guan, B. | 2022 | Zonas Costeras | 10.1016/j.atmosres.2021.105959 | https://linkinghub.elsevier.com/retrieve/pii/S0169809521005159 | 105959 | Vol: 266 | 0169-8095 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | This study highlights the occurrence of atmospheric rivers (ARs) over northwest Africa towards Europe, which were accompanied by intense episodes of Saharan dust transport all the way to Scandinavia, in the winter season. Using a combination of observational and reanalysis data, we investigate two extreme dusty AR events in February 2021 and assess their impact on snow melt in the Alps. The warm, moist, and dusty air mass (spatially-averaged 2-meter temperature and water vapour mixing ratio anomalies of up to 8 K and 3 g kg−1, and aerosol optical depths and dust loadings of up to 0.85 and 11 g m−2, respectively) led to a 50% and 40% decrease in snow depth and surface albedo, respectively, in less than one month during the winter season. ARs over northwest Africa show increasing trends over the past 4 decades, with 78% of AR events associated with severe dust episodes over Europe. © 2021 The Authors |
| Declining honey production and beekeeper adaptation to climate change in Chile | Progress in Physical Geography: Earth and Environment | Gajardo-Rojas, M.; Muñoz, A.; Barichivich, J.; Klock-Barría, K.; Gayo, E.; Fontúrbel, F.; Olea, M.; Lucas, C.; Veas, C. | 2022 | Cambio de Uso de Suelo | 10.1177/03091333221093757 | http://journals.sagepub.com/doi/10.1177/03091333221093757 | 737-756 | Vol: 46 Issue: 5 | 0309-1333, 1477-0296 | Thomson Reuters ISI (SCIE) | English | Drought severity has pervasive impacts on honey production via direct impacts on water resources and nectar availability. The current mega-drought in Chile has impacts on water resources and forest vigor, particularly in the Mediterranean and Temperate regions where honey production is concentrated. While honey production plays an important role in the local rural economy and providing pollination services to other agricultural activities, studies of the long-term impacts of the mega-drought on honey production are scarce. Here, we evaluate the impact of climate variability on historical changes in honey production in the Mediterranean (32°S–37°S) and Temperate (37°S–41°S) regions of Chile, using annual honey production records of beekeepers together with national records of honey exports. We also used questionnaires and interviews to evaluate beekeeper perceptions regarding the effects of climate change on honey production and adaptation practices in both regions. Results indicated a declining trend in honey production and exports in the last decade, largely related to changes in precipitation and temperature in both regions. Declines in honey production affected 82% of beekeepers, 80% of whom had employed adaptive measures, and 74% considered that these measures were effective. The drier, warmer Mediterranean region showed more severe declines in precipitation and honey production, which beekeepers reported as a main contributing factor to transhumance from the Mediterranean to the Temperate region. This is the first study to show the effects of drought on honey production in Chile, providing a foundation for future climate change adaptation strategies within apiculture. | |
| CLSoilMaps: A national soil gridded product for Chile | Galleguillos, Mauricio; Dinamarca, Diego; Seguel, Oscar; Faundez, Carlos | 2022 | 10.5281/zenodo.7464210 | https://zenodo.org/record/7464210 | Zenodo | English | CLSOILMAPS presents a newly gridded database of soil physical properties and soil hydraulic parameters based on digital soil mapping (DSM) techniques and a pedotransfer function (Rosetta V3) at close to 100m of spatial resolution covering the continental area of Chile and binational basins shared with Argentina for six standardized depths following GlobalSoilMap project standards. Maps were based on a newly compiled soil profile database covering different land use conditions (e.g. agricultural, forest, peatland, shrubland, and Andean grassland), and several environmental covariates based on the SCORPAN soil forming factors. DSM models showed moderate to good accuracies with R2 ranging from 0.76-0.88 for bulk density, 0.50-0.76 for clay, and 0.67-0.84 for sand. Silt maps were derived from clay and sand predictions taking advantage of the compositional nature of the particle size fraction. Field capacity, permanent wilting point, total available water capacity, and Van Genuchten´s soil hydraulic parameters were derived with Rosetta V3 algorithm. | ||||||
| Tree-ring distinctness, dating potential and climatic sensitivity of laurel forest tree species in Tenerife Island | Dendrochronologia | García-López, M.; Rozas, V.; Olano, J.; Sangüesa-Barreda, G.; García-Hidalgo, M.; Gómez-González, S.; López-Rubio, R.; Fernández-Palacios, J.; García-González, I.; García-Cervigón, A. | 2022 | Cambio de Uso de Suelo | 10.1016/j.dendro.2022.126011 | https://linkinghub.elsevier.com/retrieve/pii/S1125786522000911 | 126011 | Vol: 76 | 11257865 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Macaronesian laurel forests are the only remnants of a subtropical palaeoecosystem dominant during the Tertiary in Europe and northern Africa. These biodiverse ecosystems are restricted to cloudy and temperate insular environments in the North Atlantic Ocean. Due to their reduced distribution area, these forests are particularly vulnerable to anthropogenic disturbances and changes in climatic conditions. The assessment of laurel forest trees’ response to climate variation by dendrochronological methods is limited because it was assumed that the lack of marked seasonality would prevent the formation of distinct annual tree rings. The aims of this study were to identify the presence of annual growth rings and to assess the dendrochronological potential of the most representative tree species from laurel forests in Tenerife, Canary Islands. We sampled increment cores from 498 trees of 12 species in two well-preserved forests in Tenerife Island. We evaluated tree-ring boundary distinctness, dating potential, and sensitivity of tree-ring growth to climate and, particularly, to drought occurrence. Eight species showed clear tree-ring boundaries, but synchronic annual tree rings and robust tree-ring chronologies were only obtained for Laurus novocanariensis, Ilex perado subsp. platyphylla, Persea indica and Picconia excelsa, a third of the studied species. Tree-ring width depended on water balance and drought occurrence, showing sharp reductions in growth in the face of decreased water availability, a response that was consistent among species and sites. Inter-annual tree-ring width variation was directly dependent on rainfall input in the humid period, from previous October to current April. The four negative pointer years 1995, 1999, 2008 and 2012 corresponded to severe drought events in the study area. This study gives the first assessment of dendrochronological potential and tree-ring climate sensitivity of tree species from the Tenerife laurel forest, which opens new research avenues for dendroecological studies in Macaronesian laurel forests. © 2022 The Authors |
| Running a scientific conference during pandemic times | Bulletin of the American Meteorological Society | Garreaud, R.; Ralph, M.; Wilson, A.; Ramos, A.; Eiras-Barca, J.; Steen-Larsen, H.; Rutz, J.; Albano, C.; Tilinina, N.; Warner, M.; Viale, M.; Rondanelli, R.; McPhee, J.; Valenzuela, R.; Gorodetskaya, I. | 2022 | Agua y Extremos; Zonas Costeras | 10.1175/BAMS-D-22-0023.1 | https://journals.ametsoc.org/view/journals/bams/aop/BAMS-D-22-0023.1/BAMS-D-22-0023.1.xml | E1650-E1657 | Vol: 103 | 0003-0007, 1520-0477 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | |
| A Cross‐Cutting Approach for Relating Anthropocene, Environmental Injustice and Sacrifice Zones | Earth's Future | Gayo, E.; Muñoz, A.; Maldonado, A.; Lavergne, C.; Francois, J.; Rodríguez, D.; Klock‐Barría, K.; Sheppard, P.; Aguilera‐Betti, I.; Alonso‐Hernández, C.; Mena‐Carrasco, M.; Urquiza, A.; Gallardo, L. | 2022 | Agua y Extremos; Ciudades Resilientes | 10.1029/2021EF002217 | https://onlinelibrary.wiley.com/doi/10.1029/2021EF002217 | arte2021EF002217 | Vol: 10 Issue: 4 | 2328-4277, 2328-4277 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Anthropocene is an uneven phenomenon. Accelerated shifts in the functioning of the Earth System are mainly driven by the production and consumption of wealthy economies. Social, environmental and health costs of such industrialization, however, bear on low-income communities inhabiting severely degraded territories by polluting activities (i.e., sacrifice zones). How global, national and local socio-economic and governance processes have interacted in perpetuating socio-environmental inequalities in these territories has been rarely explored. Here, we develop an historical quantitative approach integrating a novel chemostratigraphic record, data on policy making, and socio-economic trends to evaluate the feedback relationship between environmental injustice and Anthropocene in sacrifice zones. We specifically outline a case study for the Puchuncaví valley -one of the most emblematic sacrifice zones from Chile-. We verify an ever-growing burden of heavy metals and metalloids over the past five decades paced by the staggering expansion of local industrial activities, which has ultimately been spurred by national and transnational market forces. Local poverty levels have declined concomitantly, but this path toward social equality is marginal as costs of pollution have grown through time. Indeed, national and international pollution control actions appear insufficient in mitigating the cumulative impact brought by highly toxic elements. Thus, our sub-decadal reconstruction for pollution trends over the past 136 years from a sediment record, emerges as a science-based tool for informing the discussion on Anthropocene governance. Furthermore, it helps to advance in the assessment of environmental inequality in societal models that prioritize economic growth to the detriment of socio-environmental security. © 2022 The Authors. Earth's Future published by Wiley Periodicals LLC on behalf of American Geophysical Union. |
| A coupled modeling approach to assess the effect of forest policies in water provision: A biophysical evaluation of a drought-prone rural catchment in south-central Chile | Science of The Total Environment | Gimeno, F.; Galleguillos, M.; Manuschevich, D.; Zambrano-Bigiarini, M. | 2022 | Agua y Extremos; Cambio de Uso de Suelo | 10.1016/j.scitotenv.2022.154608 | https://linkinghub.elsevier.com/retrieve/pii/S0048969722017016 | 154608 | Vol: 830 | 0048-9697 | Thomson Reuters ISI (SCIE) | English | The effect of different forest conservation policies on water provision has been poorly investigated due to a lack of an integrative methodological framework that enables its quantification. We developed a method for assessing the effects of forest conservation policies on water provision for rural inhabitants, based on a land-use model coupled with an eco-hydrological model. We used as a case study the Lumaco catchment, Chile, a territory dominated by native forests (NF) and non-native tree farms, with an extended dry period where nearly 12,600 people of rural communities get drinking water through water trucks. We analyzed three land-use policy scenarios: i) a baseline scenario based on historical land-cover maps; ii) a NF Recovery and Protection (NFRP) scenario, based on an earlier implementation of the first NF Recovery and Forestry Development bill; and iii) a Pristine (PR) scenario, based on potential vegetation belts; the latter two based on Dyna CLUE, and simulated between 1990 and 2015. Impacts on water provision from each scenario were computed with SWAT. The NFRP scenario resulted in an increase of 6974 ha of NF regarding the baseline situation, and the PR scenario showed an increase of 26,939 ha of NF. Despite large differences in NF areas, slight increases in inflows (Q) were found between the NFRP and the PR scenarios, with relative differences with respect to the baseline of 0.3% and 2.5% for NFRP and PR, respectively. Notwithstanding, these small differences in the NFRP scenario, they become larger if we analyze the cumulative values during the dry season only (December, January, and February), where they reach 1.1% in a normal year and 3.1% in a dry year. Flows increases were transformed into water truck costs resulting in up to 441,876 USD (monthly) of fiscal spending that could be avoided during a dry period. © 2022 Elsevier B.V. | |
| Surviving in a hostile landscape: Nothofagus alessandrii remnant forests threatened by mega-fires and exotic pine invasion in the coastal range of central Chile | Oryx | González, M.; Galleguillos, M.; Lopatin, J.; Leal, C.; Becerra-Rodas, C.; Lara, A.; San Martín, J. | 2022 | Cambio de Uso de Suelo | 10.1017/S0030605322000102 | https://www.cambridge.org/core/product/identifier/S0030605322000102/type/journal_article | 1-11 | Vol: 57 | 0030-6053, 1365-3008 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract Nothofagus alessandrii , categorized as Endangered on the IUCN Red List, is an endemic, deciduous tree species of the coastal range of central Chile. We assessed the effects of fire severity, invasion by the exotic fire-prone Pinus radiata , and land-cover composition and configuration of the landscape on the resilience of fragments of N. alessandrii after a mega-fire in 2017. We used remote sensing data to estimate land-use classes and cover, fire severity and invasion cover of P. radiata . We monitored forest composition and structure and post-fire responses of N. alessandrii forests in situ for 2 years after the mega-fire. In the coastal Maule region wildfires have been favoured by intense drought and widespread exotic pine plantations, increasing the ability of fire-adapted invasive species to colonize native forest remnants. Over 85% of N. alessandrii forests were moderately or severely burnt. The propagation and severity of fire was probably amplified by the exotic pines located along the edges of, or inside, the N. alessandrii fragments and the highly flammable pine plantations surrounding these fragments (> 60% of land use is pine plantations). Pinus radiata , a fire-adapted pioneer species, showed strong post-fire recruitment within the N. alessandrii fragments, especially those severely burnt. Positive feedback between climate change (i.e. droughts and heat waves), wildfires and pine invasions is driving N. alessandrii forests into an undesirable and probably irreversible state (i.e. a landscape trap). A large-scale restoration programme to design a diverse and less flammable landscape is needed to avoid the loss of these highly threatened forest ecosystems. |
| Carbon stocks across different environments, disturbance regimes, and stand age in Fitzroya cupressoides forests, the longest-lived species of the southern hemisphere | Frontiers in Forests and Global Change | González, M.; Lara, A.; Urrutia-Jalabert, R.; Bustos-Salazar, A.; Ruiz-Gómez, C.; Aravena, J. | 2022 | Cambio de Uso de Suelo | 10.3389/ffgc.2022.960429 | https://www.frontiersin.org/articles/10.3389/ffgc.2022.960429/full | 960429 | Vol: 5 | 2624-893X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Forest disturbances influence Fitzroya cupressoides forest structure and carbon stocks at multiple spatial and temporal scales. Natural disturbances such as landslides and volcanism affect and give rise to the mostly pristine Fitzroya stands present in the Andean cordillera. On the other hand, mostly human-caused fires and logging have been the main processes shaping the structure of Fitzroya stands in the Coastal range and of Fitzroya small remnants in the Central depression. The main goal of this study was to assess the carbon stocks and accumulation rates of Fitzroya forest stands according to their development stage under different disturbance regimes and environmental conditions given by the three physiographic units where the species grows (Coastal range, Central depression, and Andean range). The site selection included an age sequence of stands, known as a chronosequence approach. We identified Fitzroya post-disturbance stands in three different stages of development: young forest stage (mean stand age of the main cohort ≤ 200 years old), mature forest stage (200–800 years old), and old growth forest stage (800–1,500 years old). The following biomass components were considered: living standing trees, dead standing trees (snags), and logs from dead trees laying on the ground (coarse woody debris). Old-growth Fitzroya forests reached a mean total carbon stock (standing live trees, snags, and coarse woody debris) of 507, 279, and 331 Mg C ha −1 in the Andean and Coastal ranges, and Central depression, respectively. Fitzroya cupressoides contributes, in average, more than 80% to the total carbon stock in the Andean and Coastal ranges, and 63% in the Central depression. The remainder corresponds mainly to Nothofagus spp. The high carbon stocks in old-growth stands in the Andean range are explained by Fitzroya longevity, larger size, wood decay resistance, and the low recurrence of volcanic events. Carbon accumulation rates differ between the forests in the three physiographic units (Central depression>Andean range>Coastal range), mainly due to the different growth rates and environmental conditions present in each unit. In the context of climate change, conserving old-growth stands with large biomass and carbon stocks and restoring Fitzroya forests should be recognized as a key contribution toward national and global goals to mitigate global warming. |
| The Gill Microbiota of Argopecten purpuratus Scallop Is Dominated by Symbiotic Campylobacterota and Upwelling Intensification Differentially Affects Their Abundance | Microorganisms | GonzálezR, R.; Henríquez-Castillo, C.; Lohrmann, K.; Romero, M.; Ramajo, L.; Schmitt, P.; Brokordt, K. | 2022 | Zonas Costeras | 10.3390/microorganisms10122330 | https://www.mdpi.com/2076-2607/10/12/2330 | 2330 | Vol: 10 Issue: 12 | 2076-2607 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Despite the great importance of gills for bivalve mollusks (respiration, feeding, immunity), the microbiota associated with this tissue has barely been characterized in scallops. The scallop Argopecten purpuratus is an important economic resource that is cultivated in areas where coastal upwelling is intensifying by climate change, potentially affecting host-microbiota interactions. Thus, we first characterized the bacterial community present in gills from cultivated scallops (by 16S rRNA gene amplicon sequencing) and assessed their stability and functional potential in animals under farm and laboratory conditions. Results showed that under both conditions the gill bacterial community is dominated by the phylum Campylobacterota (57%), which displays a chemoautotrophic potential that could contribute to scallop nutrition. Within this phylum, two phylotypes, namely symbionts A and B, were the most abundant; being, respectively, taxonomically affiliated to symbionts with nutritional functions in mussel gills, and to uncultured bacteria present in coral mucus. Additionally, in situ hybridization and scanning electron microscopy analyses allowed us to detect these symbionts in the gills of A. purpuratus. Given that shifts in upwelling phenology can cause disturbances to ecosystems, affecting bacteria that provide beneficial functions to the host, we further assessed the changes in the abundance of the two symbionts (via qPCR) in response to a simulated upwelling intensification. The exposure to combined decreasing values in the temperature, pH, and oxygen levels (upwelling conditions) favored the dominance of symbiont B over symbiont A; suggesting that symbiont abundances are modulated by these environmental changes. Overall, results showed that changes in the main Campylobacterota phylotypes in response to upwelling intensification could affect its symbiotic function in A. purpuratus under future climate change scenarios. These results provide the first insight into understanding how scallop gill-microbial systems adapt and respond to climate change stressors, which could be critical for managing health, nutrition, and scallop aquaculture productivity. |
| Drivers of Flammability of Eucalyptus globulus Labill Leaves: Terpenes, Essential Oils, and Moisture Content | Forests | Guerrero, F.; Carmona, C.; Hernández, C.; Toledo, M.; Arriagada, A.; Espinoza, L.; Bergmann, J.; Taborga, L.; Yañez, K.; Carrasco, Y.; Muñoz, A. | 2022 | Agua y Extremos | 10.3390/f13060908 | https://www.mdpi.com/1999-4907/13/6/908 | 908 | Vol: 13 Issue: 6 | 1999-4907 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Mediterranean climate regions have become more vulnerable to fire due to the extreme weather conditions and numerous Eucalyptus globulus plantation areas. The aim of this study is to analyze the fire hazard related to E. globulus in a forest fire scenario, based on the contrast of thermochemical parameters and their relationship with chemical properties, considering the predominant exotic forest species (E. globulus, Pinus radiata, Acacia dealbata, and Acacia melanoxylon) present in the Valparaiso region, Chile. The results revealed that although all of the studied species were highly flammable, E. globulus was extremely flammable, as its leaves contain high concentrations of essential oils, monoterpenes, and sesquiterpenes, which can generate a flammable atmosphere due to their low flashpoint and the strong negative influence shown between the essential oils, volatile terpenes, and limonene concentration. Moreover, the heat of combustion of E. globulus was positively correlated with its high essential oil contents. Finally, all of the studied species had low flashpoints and high heating values; therefore, they are predisposed to ignite in the presence of a heat source, releasing high amounts of energy during combustion, which contributes to the risk of the formation and spread of canopy fires among these tree formations. |
| Moving towards the ecological intensification of tree plantations | Trends in Plant Science | Gómez-González, S.; Paniw, M.; Blanco-Pastor, J.; García-Cervigón, A.; Godoy, O.; Herrera, J.; Lara, A.; Miranda, A.; Ojeda, F.; Ochoa-Hueso, R. | 2022 | Cambio de Uso de Suelo | 10.1016/j.tplants.2021.12.009 | https://linkinghub.elsevier.com/retrieve/pii/S1360138521003526 | 637-645 | Vol: 27 Issue: 7 | 1360-1385 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The growing demand for timber and the boom in massive tree-planting programs could mean the spreading of mismanaged tree plantations worldwide. Here, we apply the concept of ecological intensification to forestry systems as a viable biodiversity-focused strategy that could be critical to develop productive, yet sustainable, tree plantations. Tree plantations can be highly productive if tree species are properly combined to complement their ecological functions. Simultaneously considering soil biodiversity and animal-mediated biocontrol will be critical to minimize the reliance on external inputs. Integrating genetic, functional, and demographic diversity across heterogeneous landscapes should improve resilience under climate change. Designing ecologically intensified plantations will mean breaking the timber productivity versus conservation dichotomy and assuring the maintenance of key ecosystem services at safe levels. © 2021 Elsevier Ltd |
| Climate change-related risks and adaptation potential in Central and South America during the 21st century | Environmental Research Letters | Hagen, I.; Huggel, C.; Ramajo, L.; Chacón, N.; Ometto, J.; Postigo, J.; Castellanos, E. | 2022 | Zonas Costeras | 10.1088/1748-9326/ac5271 | https://iopscience.iop.org/article/10.1088/1748-9326/ac5271 | 033002 | Vol: 17 Issue: 3 | 1748-9326 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract Climate-related risks in Central and South America have received increased attention and concern in science and policy, but an up-to-date comprehensive review and synthesis of risks and adaptation potential is currently missing. For this paper we evaluated over 200 peer-reviewed articles and grey literature documents published since 2012. We found that climate change in Central and South America during the 21st century may increase the risk to severe levels for the following topical risk clusters: (a) Food insecurity; (b) Floods and landslides; (c) Water scarcity; (d) Epidemics of vector-borne diseases; (e) Amazon Forest biome shift; (f). Coral bleaching; (g) Coastal risks of sea level rise, storm surges and erosion; (h) Systemic failure due to cascading impacts of hazards and epidemics. Our synthesis also identified feasible adaptation measures for each risk. The impacts of the risks will be heterogeneous throughout the region, with rural communities, Indigenous peoples, Afro-Latin Americans, women, disabled people, and migrants identified as being the most severely affected. We refer to a number of adaptation options for each risk. However, unabated climate change together with low adaptive capacity will strictly limit adaptation options. Immediate strengthening of policies for building adaptive capacity and increase of research on the risk-adaptation nexus in Central and South America are paramount. Our findings might contribute to guide the adjustment and emphasis of adaptation policies and climate risk management strategies from local to national level. |
| Hydrologic Sensitivities and ENSO Variability Across Hydrological Regimes in Central Chile (28°–41°S) | Water Resources Research | Hernandez, D.; Mendoza, P.; Boisier, J.; Ricchetti, F. | 2022 | Agua y Extremos | 10.1029/2021WR031860 | https://onlinelibrary.wiley.com/doi/10.1029/2021WR031860 | arte2021WR031860 | Vol: 58 Issue: 9 | 0043-1397, 1944-7973 | Thomson Reuters ISI (SCIE) | English | There is strong evidence of El Niño-Southern Oscillation (ENSO) teleconnections in the South Pacific and related impacts on the precipitation regime in Chile; nonetheless, many aspects of the hydrological propagation and temperature responses to ENSO remain unclear in this region. We examine fluctuations across 59 near-natural catchments in central Chile (28°–41°S) under contrasting ENSO phases during the period 1981–2019. Our results show statistically significant ENSO-related hydroclimatic anomalies in almost all watersheds analyzed, which confirms the major influence of ENSO within this domain. By comparing El Niño phases against La Niña, we observe generally wetter conditions, warmer winters, cooler late springs, lower (higher) runoff ratios in snowmelt-driven (rainfall-driven) basins, and longer storm durations while storm frequencies (i.e., number of events of consecutive days with precipitation) are preserved. Additionally, low (high) elevation catchments are related to positive (negative) streamflow sensitivities to winter temperature, which increase in magnitude with the evaporative index; besides, catchments with sharp warm-and-dry conditions yield largely negative sensitivities to late spring temperature. Further, positive streamflow anomalies in rainfall-driven catchments are explained by temperature and precipitation ENSO-related amplitudes (El Niño minus La Niña) that separately favor streamflow; however, in mixed regimes and snowmelt-driven basins these results are spatially scattered. Hence, this study supports that meteorological, hydrological, and physiographic attributes modulate the translation of climate variability into river hydrology. The results presented here unravel the joint effects of precipitation and seasonal temperature fluctuations through different hydrological regimes, across a region that encloses populated cities and water-intensive activities. © 2022. American Geophysical Union. All Rights Reserved. | |
| Multiple motion encoding in phase-contrast MRI: A general theory and application to elastography imaging | Medical Image Analysis | Herthum, H.; Carrillo, H.; Osses, A.; Uribe, S.; Sack, I.; Bertoglio, C. | 2022 | Ciudades Resilientes | 10.1016/j.media.2022.102416 | https://linkinghub.elsevier.com/retrieve/pii/S1361841522000664 | 102416 | Vol: 78 | 1361-8415 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | While MRI allows to encode the motion of tissue in the magnetization's phase, it remains yet a challenge to obtain high fidelity motion images due to wraps in the phase for high encoding efficiencies. Therefore, we propose an optimal multiple motion encoding method (OMME) and exemplify it in Magnetic Resonance Elastography (MRE) data. OMME is formulated as a non-convex least-squares problem for the motion using an arbitrary number of phase-contrast measurements with different motion encoding gradients (MEGs). The mathematical properties of OMME are proved in terms of standard deviation and dynamic range of the motion's estimate for arbitrary MEGs combination which are confirmed using synthetically generated data. OMME's performance is assessed on MRE data from in vivo human brain experiments and compared to dual encoding strategies. The unwrapped images are further used to reconstruct stiffness maps and compared to the ones obtained using conventional unwrapping methods. OMME allowed to successfully combine several MRE phase images with different MEGs, outperforming dual encoding strategies in either motion-to-noise ratio (MNR) or number of successfully reconstructed voxels with good noise stability. This lead to stiffness maps with greater resolution of details than obtained with conventional unwrapping methods. The proposed OMME method allows for a flexible and noise robust increase in the dynamic range and thus provides wrap-free phase images with high MNR. In MRE, the method may be especially suitable when high resolution images with high MNR are needed. © 2022 |
| Scientists and climate governance: A view from the South | Environmental Science & Policy | Ibarra, C.; Jiménez, G.; O’Ryan, R.; Blanco, G.; Cordero, L.; Insunza, X.; Moraga, P.; Rojas, M.; Sapiains, R. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.envsci.2022.09.012 | https://linkinghub.elsevier.com/retrieve/pii/S1462901122002908 | 396-405 | Vol: 137 | 1462-9011 | Thomson Reuters ISI (SCIE) | English | The importance of science for climate governance has strengthened over time and the topic inspires prolific academic writing on the influence of scientists and scientific knowledge on policy decisions. One of the streams of research in the field is inspired by Cash´s (2003) seminal work highlighting how the role of scientists depends on perceptions of salience, credibility and legitimacy. Other views call for attention to the politics involved in scientific performance while influencing policy and on the local circumstances, considering the many ways in which societies relate to science and expertise. The role of scientists in climate governance is a contested issue, relevant for many research centres aiming to influence policy decisions given the urgency of the climate crisis. To better understand this role, we reviewed mainstream international literature and identified four main approaches, which we label: scientific usable knowledge, politics of science, critical approaches and hybrid approaches. We contrasted the results with the experience of scientists from a Chilean climate research centre, to provide a view from the South on the role of scientists in climate governance. Our results show that Cash´s approach was a common ground for Chilean climate scientists, upon which they build ideas on the importance of building long-term relationships between scientists and policy makers. However, they also acknowledged the need to take into consideration the role of politics in climate-related decisions and the power relations and actor´s interests. © 2022 Elsevier Ltd | |
| Simplified two-dimensional model for global atmospheric dynamics | Physics of Fluids | Jacques-Coper, M.; Ortiz-Guzmán, V.; Zanelli, J. | 2022 | Zonas Costeras | 10.1063/5.0119855 | https://aip.scitation.org/doi/10.1063/5.0119855 | 116610 | Vol: 34 Issue: 11 | 1070-6631, 1089-7666 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | We present a simplified model of the atmosphere of a terrestrial planet as an open two-dimensional system described by an ideal gas with velocity [Formula: see text], density ρ, and temperature T fields. Starting with the Chern–Simons equations for a free inviscid fluid, the external effects of radiation and the exchange of matter with the strata, as well as diffusion and dissipation, are included. The resulting dynamics is governed by a set of nonlinear differential equations of the first order in time. This defines an initial value problem that can be integrated given the radiation balance of the planet. If the nonlinearities are neglected, the integration can be done in analytic form using standard Green function methods, with small nonlinearities incorporated as perturbative corrections in a consistent way. If the nonlinear approximation is not justified, the problem can be integrated numerically. The analytic expressions as well as the simulations of the linear regime for a continuous range of parameters in the equations are provided, which allows to explore the response of the model to changes of those parameters. In particular, it is observed that a 2.5% reduction in the emissivity of the atmosphere can lead to an increase of 7 °C of the average global temperature. |
| Effect of tree demography and flexible root water uptake for modeling the carbon and water cycles of Amazonia | Ecological Modelling | Joetzjer, E.; Maignan, F.; Chave, J.; Goll, D.; Poulter, B.; Barichivich, J.; Maréchaux, I.; Luyssaert, S.; Guimberteau, M.; Naudts, K.; Bonal, D.; Ciais, P. | 2022 | Cambio de Uso de Suelo | 10.1016/j.ecolmodel.2022.109969 | https://doi.org/10.1016/j.ecolmodel.2022.109969 | art: 109969 | Vol: 469 | 0304-3800 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Amazonian forest plays a crucial role in regulating the carbon and water cycles in the global climate system. However, the representation of biogeochemical fluxes and forest structure in dynamic global vegetation models (DGVMs) remains challenging. This situation has considerable implications to simulate the state and dynamics of Amazonian forest. This study aims at simulating the dynamic of the evapotranspiration (ET), productivity (GPP), biomass (AGB) and forest structure of wet tropical forests in the Amazon basin using the updated ORCHIDEE land surface model. The latter is improved for two processes: stand structure and demography, and plant water uptake by roots. Stand structure is simulated by adapting the CAN version of ORCHIDEE, originally developed for temperate forests. Here, we account for the permanent recruitment of young individual trees, the distribution of stand level growth into 20 different cohorts of variable diameter classes, and mortality due to asymmetric competition for light. Plant water uptake is simulated by including soil-to-root hydraulic resistance (RS). To evaluate the effect of the soil resistance alone, we performed factorial simulations with demography only (CAN) and both demography and resistance (CAN-RS). AGB, ET and GPP outputs of CAN-RS are also compared with the standard version of ORCHIDEE (TRUNK) for which eco-hydrological parameters were tuned globally to fit GPP and evapotranspiration at flux tower sites. All the model versions are benchmarked against in situ and regional datasets. We show that CAN-RS correctly reproduce stand level structural variables (as CAN) like diameter classes and tree densities when validated using in-situ data. Besides offering the key advantage to simulate forest's structure, it also correctly simulates ET and GPP and improves fluxes spatial patterns when compared to TRUNK. With the new formulation of soil water uptake, which is driven by soil water availability rather than root-biomass, the simulated trees preferentially use water in the deepest soil layers during the dry seasons. This improves the seasonality of ET and GPP compared to CAN, especially on clay soils for which the soil moisture potential drops rapidly in the dry season. Nevertheless, since demography parameters in CAN-RS are constant for all evergreen tropical forests, spatial variability of AGB and basal area across the Amazon remains too uniform compared to observations, and are very comparable to the TRUNK. Additional processes such as climate driven mortality and phosphorus limitation on growth leading to the prevalence of species with different functional traits across the Amazon need to be included in the future development of this model. © 2022 |
| Forest restoration and hydrology | Forest Ecology and Management | Jones, J.; Ellison, D.; Ferraz, S.; Lara, A.; Wei, X.; Zhang, Z. | 2022 | Cambio de Uso de Suelo | 10.1016/j.foreco.2022.120342 | https://linkinghub.elsevier.com/retrieve/pii/S037811272200336X | 120342 | Vol: 520 | 0378-1127 | Thomson Reuters ISI (SCIE) | English | Forest restoration aims to increase forest cover, structure, function, and/or species composition, and it influences hydrology through the partitioning of precipitation into evapotranspiration and streamflow. This paper provides a conceptual framework for forest restoration and hydrology, reviews the literature on forest hydrology that is relevant to forest restoration, and assesses practical forest restoration approaches, their hydrologic effects, and tradeoffs. The hydrologic effects of three types of forest are assessed: mature and old-growth forests, which often are the reference model for restoration; managed forest plantations, which dominated early efforts for forest restoration; and the early stages of native forest succession, an increasingly popular, ecologically-oriented or nature-based approach to forest restoration. This review indicates that mature and old-growth forests have high evapotranspiration and consistent water yield, provided by moderated peak discharges and sustained low flows, while water yield is low from managed forest plantations, especially during dry periods. The early stages of native forest succession may provide greater water yield and increased low flows compared with managed plantations. Inclusion of native species and natural processes in forest restoration can increase some hydrological benefits relative to other forest restoration approaches. Although forest restoration affects hydrology, few studies examine the hydrologic effects of specific forest restoration practices such as choice of species, silvicultural practices, legacies of past land use, and geographic setting. Forest managers and ecologists can play valuable roles by designing studies that explore the hydrologic effects of forest restoration approaches on time scales relevant to ecological succession and forest management under a changing climate. © 2022 Elsevier B.V. | |
| The challenge of unprecedented floods and droughts in risk management | Nature | Kreibich, H.; Van Loon, A.; Schröter, K.; Ward, P.; Mazzoleni, M.; Sairam, N.; Abeshu, G.; Agafonova, S.; AghaKouchak, A.; Aksoy, H.; Alvarez-Garreton, C.; Aznar, B.; Balkhi, L.; Barendrecht, M.; Biancamaria, S.; Bos-Burgering, L.; Bradley, C.; Budiyono, Y.; Buytaert, W.; Capewell, L.; Carlson, H.; ... | 2022 | Agua y Extremos | 10.1038/s41586-022-04917-5 | https://www.nature.com/articles/s41586-022-04917-5 | 80-86 | Vol: 608 Issue: 7921 | 0028-0836, 1476-4687 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Abstract Risk management has reduced vulnerability to floods and droughts globally 1,2 , yet their impacts are still increasing 3 . An improved understanding of the causes of changing impacts is therefore needed, but has been hampered by a lack of empirical data 4,5 . On the basis of a global dataset of 45 pairs of events that occurred within the same area, we show that risk management generally reduces the impacts of floods and droughts but faces difficulties in reducing the impacts of unprecedented events of a magnitude not previously experienced. If the second event was much more hazardous than the first, its impact was almost always higher. This is because management was not designed to deal with such extreme events: for example, they exceeded the design levels of levees and reservoirs. In two success stories, the impact of the second, more hazardous, event was lower, as a result of improved risk management governance and high investment in integrated management. The observed difficulty of managing unprecedented events is alarming, given that more extreme hydrological events are projected owing to climate change 3 . |
| Association between the diabetic foot amputation index and metabolic compensation in diabetes mellitus; [Asociación entre el índice de amputación por pie diabético y los indicadores de atención y manejo de diabetes mellitus tipo 2 en los Centros de Salud del Servicio Metropolitano Oriente, entre 2014 y 2018] | Revista Medica de Chile | Kuschel, F.; Orellana, I.; Valdés, M. | 2022 | Ciudades Resilientes | 10.4067/s0034-98872022000700912 | https://doi.org/10.4067/s0034-98872022000700912 | 912-918 | Vol: 150 Issue: 7 | 00349887 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | Spanish | Background: Diabetic foot amputation is a public health challenge due to the increasing prevalence of type 2 diabetes mellitus (T2D). Although there are many health indicators aimed at the management and control of T2D and its complications, amputations persist. Aim: To evaluate the association between diabetic foot amputation index and indicators of care and management of T2D in primary care centers of the eastern section of Santiago, Chile. Material and Methods: We conducted a mixed ecological study and included information from the Monthly Statistical report of different public health centers from 2014 to 2018. We also analyzed the hospital discharge records from an individual tertiary public health center. The annual index for diabetic foot amputation per 100,000 diabetic patients was used as a response variable. The diabetic compensation percentage was calculated as the proportion of adults with a glycosylated hemoglobin below 7% or the proportion of older people with a value below 8%. The diabetic decompensation percentage was calculated as the proportion of people with a glycosylated hemoglobin over 9%. Results: A high variability in demographic and management indicators was observed between communes and centers in the study period. Bivariate analysis showed a significant correlation between the amputation index, decompensation, and insulin use. In a regression analysis, the amputation index was significantly associated with the diabetic compensation percentage (β = -3.5; p < 0.05) and a high decompensation percentage (β = 12.3; p < 0.005). Conclusions: The diabetic foot amputation index was associated with diabetic compensation and decompensation indicators. © 2022 Sociedad Medica de Santiago. All rights reserved. |
| Contaminación y sociedad: la construcción social de la polución atmosférica entre la prensa chilena y los Planes de Prevención y Descontaminación Atmosférica | Universum | Labraña, J.; Billi, M.; Arrieta Ruiz, D.; Urquiza Gómez, A. | 2022 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.4067/s0718-23762022000200519 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-23762022000200519&lng=en&nrm=iso&tlng=en | 519-538 | Vol: 37 Issue: 2 | 0718-2376 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | Air pollution has become a central issue in recent decades. The present research aims to examine how the press media construct the problem of air pollution in the Metropolitan Region, Chile. To this end, news related to air pollution in the Metropolitan Region published in the digital sites of El Mercurio and La Nación between 2003 and 2018 were analyzed, assessing their closeness with respect to the construction of air pollution in science (assessed by analyzing publications on the topic indexed in Web of Science) and in politics (assessed by analyzing the Atmospheric Prevention and Decontamination Plans). The results suggest the existence of four different interpretative frameworks in the period that operate by selectively translating the results of scientific research into inputs for public policy, thus forming an idiosyncratic construction of the causes, consequences, and solutions to pollution. © 2022 Universidad de Talca. All rights reserved. |
| Extreme indices of temperature and precipitation in South America: trends and intercomparison of regional climate models | Climate Dynamics | Lagos-Zúñiga, M.; Balmaceda-Huarte, R.; Regoto, P.; Torrez, L.; Olmo, M.; Lyra, A.; Pareja-Quispe, D.; Bettolli, M. | 2022 | Zonas Costeras | 10.1007/s00382-022-06598-2 | https://doi.org/10.1007/s00382-022-06598-2 | 1-22 | Vol: - | 0930-7575 | Thomson Reuters ISI (SCIE) | English | Regional Climate Models (RCMs) provide climate information required for evaluating vulnerability, impacts, and adaptation at finer scales than their global driving models. As they explicitly resolve the basic conservation and state equations, they solve physics with more detail, conserving teleconnection of larger scales provided by Global Climate Models (GCMs). In South America (SA), the regional simulations have been historically evaluated principally on climatological aspects, but the representativeness of extremes still needs a more profound assessment. This study aims to analyze three RCMs (RegCM4-7, REMO2015, and Eta) driven by different GCMs in SA, focusing on their capacity to reproduce extreme historical indices of daily precipitation and temperature. The indices of maximum consecutive 5 days precipitation (Rx5day), Consecutive Dry Days (CDD), daily maximum and minimum annual temperature (TXx and TNn, respectively) were evaluated regarding the historical spatio-temporal variability and trends. Furthermore, their projections for the 2071–2099 period, under the Representative Concentration Pathway 8.5 scenario, were analyzed. The historical behavior of RCMs (1981–2005) was compared with two gridded products: Climate Prediction Center (CPC) and agrometeorological indicators derived from the fifth generation of global reanalysis produced by the ECMWF (AgERA5), previously compared with records from meteorological stations to evaluate them. The results show that the highest differences within the gridded products and stations were observed in the regions with more scarce surface stations (North and West of SA) and with complex topography (The Andes Cordillera), being more pronounced in the precipitation-based indices. We found that RCMs generally show more agreement in the spatial variability than in the inter-annual variability for all the indices and SA regions. When analyzing the observed trends, all models better reproduced the long-term variability of extreme temperature indices than those of rainfall. More disagreement was observed for Rx5day and CDD indices trends, including substantial spatial heterogeneities in both magnitude and sign of tendency. Climate change projections exhibited significant agreement to warmer conditions in TXx and TNn, but precipitation signals differed between RCMs and the driving GCM within each regional model. Maximum dry spells are expected to increase in almost all SA regions, whereas the climate change signals in extreme precipitation events are more consistent over southeastern SA (northern and southwestern SA), with positive (negative) changes by the end of the century. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. | |
| Disturbance alters relationships between soil carbon pools and aboveground vegetation attributes in an anthropogenic peatland in Patagonia | Ecology and Evolution | Lopatin, J.; Araya‐López, R.; Galleguillos, M.; Perez‐Quezada, J. | 2022 | Cambio de Uso de Suelo | 10.1002/ece3.8694 | https://onlinelibrary.wiley.com/doi/10.1002/ece3.8694 | arte8694 | Vol: 12 Issue: 3 | 2045-7758, 2045-7758 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Anthropogenic-based disturbances may alter peatland soil–plant causal associations and their ability to sequester carbon. Likewise, it is unclear how the vegetation attributes are linked with different soil C decomposition-based pools (i.e., live moss, debris, and poorly- to highly-decomposed peat) under grassing and harvesting conditions. Therefore, we aimed to assess the relationships between aboveground vegetation attributes and belowground C pools in a Northern Patagonian peatland of Sphagnum magellanicum with disturbed and undisturbed areas. We used ordination to depict the main C pool and floristic gradients and structural equation modeling (SEM) to explore the direct and indirect relationships among these variables. In addition, we evaluated whether attributes derived from plant functional types (PFTs) are better suited to predict soil C pools than attributes derived from species gradients. We found that the floristic composition of the peatland can be classified into three categories that follow the C pool gradient. These categories correspond to (1) woody species, such as Baccharis patagonica, (2) water-logged species like Juncus procerus, and (3) grasslands. We depicted that these classes are reliable indicators of soil C decomposition stages. However, the relationships change between management. We found a clear statistical trend showing a decrease of live moss, debris, and poorly-decomposed C pools in the disturbed area. We also depicted that plant diversity, plant height, and PFT composition were reliable indicators of C decomposition only under undisturbed conditions, while the species-based attributes consistently yielded better overall results predicting soil C pools than PFT-based attributes. Our results imply that managed peatlands of Northern Patagonia with active grassing and harvesting activities, even if small-scaled, will significantly alter their future C sequestration capacities by decreasing their live and poorly-decomposed components. Finally, aboveground vegetation attributes cannot be used as proxies of soil C decomposition in disturbed peatlands as they no longer relate to decomposition stages. © 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. |
| Cross-continental hydroclimate proxies: Tree-rings in Central Chile reconstruct historical streamflow in Southeastern South American rivers | Progress in Physical Geography: Earth and Environment | Lucas, C.; Aguilera-Betti, I.; Muñoz, A.; Puchi, P.; Sapriza, G.; Profumo, L.; Maxwell, R.; Venegas-González, A. | 2022 | Agua y Extremos | 10.1177/03091333211067466 | http://journals.sagepub.com/doi/10.1177/03091333211067466 | 030913332110674 | Vol: 46 | 0309-1333 | Thomson Reuters ISI (SCIE) | English | Regional teleconnections permit cross-continental modeling of hydroclimate throughout the world. Tree-rings are a good hydroclimatic proxy used to reconstruct drought and streamflow in regions that respond to common global forcings. We used a multi-species dataset of 32 tree-ring width chronologies from Chile and Uruguay as a climate proxy to infer annual streamflow (Q) variability in the Negro River basin, a grassland-dominated watershed of lowland Southeastern South America. A positive linear correlation between tree-ring chronologies from Central Chile and annual Negro River instrumental streamflow from 1957 to 2012 indicated a cross-continental teleconnection between hydroclimate variability in Central Chile and Northeastern Uruguay. This relationship was mediated in part by the El Niño Southern Oscillation (ENSO), whereby the El Nino 3.4 Index was positively correlated with regional rainfall, annual tree growth, and Q anomalies. Despite the proximity of Uruguayan tree-ring chronologies to Negro River hydrometric stations, the Chilean tree-ring chronologies best predicted annual streamflow. Thus, using tree-ring data from four long-term moisture-sensitive chronologies of the species Cryptocarya alba in Central Chile (32–34°S), we present the first streamflow reconstruction (1890–2009) in the lower La Plata Basin. The reconstruction supports regional evidence for increasing frequency of extreme flood years over the past century in Uruguay. We demonstrate how climate teleconnections that mediate local hydroclimate variability permit the cross-continental reconstruction of streamflow, filling a major geographical gap in historical proxies for flooding and drought in grassland biomes of the southern hemisphere. | |
| Comité Científico de Cambio Climático: Soluciones basadas en la naturaleza | Marquet, P.; Rojas, M.; Stehr, A.; Farias, L.; Gonzalez, H.; Muñoz, J.; Wagemann, E.; Rojas, C.; Rodriguez, I.; Hoyow, J. | 2022 | Ciudades Resilientes | https://comitecientifico.minciencia.gob.cl/wp-content/uploads/2022/01/Soluciones-Basadas-en-la-Naturaleza-Marquet_compressed.pdf | 78 | ||||||||
| Síntesis de las iniciativas populares de norma ambientales-climáticas para la discusión constitucional | Martinez, F.; Billi, M.; Moraga, P.; Ibarra, C.; Maillet, A. | 2022 | https://www.cr2.cl/sintesis-de-las-iniciativas-populares-de-norma-ambientales-climaticas-para-la-discusion-constitucional/ | 6 | cr2.cl | ||||||||
| Atmospheric Blocking Trends and Seasonality around the Antarctic Peninsula | Journal of Climate | Marín, J.; Bozkurt, D.; Barrett, B. | 2022 | Zonas Costeras | 10.1175/JCLI-D-21-0323.1 | https://journals.ametsoc.org/view/journals/clim/35/12/JCLI-D-21-0323.1.xml | 3803-3818 | Vol: 35 Issue: 12 | 0894-8755, 1520-0442 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Abstract We analyze the seasonal evolution and trends of atmospheric blocking from 1979 to 2018 using a geopotential-height-based method over two domains, one located to the west (150°–90°W, 50°–70°S) and the other over and to the east (90°–30°W, 50°–70°S) of the Antarctic Peninsula. Spatial patterns of geopotential heights on days with blocking feature well-defined ridge axes over and west of much of South America, and days with the most extreme blocking (above the 99th percentile) showed upper-tropospheric ridge and cutoff low features that have been associated with extreme weather patterns. Blocking days were found to be more frequent in the first half of the period (1979–98) than the second (1999–2018) in all seasons in the west domain, whereas they seem to be more common over the eastern (peninsula) domain in 1999–2018 for austral winter, spring, and autumn, although these differences were not statistically significant. West of the Antarctic Peninsula, blocking days occur most frequently when the Antarctic Oscillation (AAO) is negative, whereas they are more frequent over the peninsula when the AAO is positive. We propose that our blocking index can be used to indicate atmospheric blocking affecting the Antarctic Peninsula, similar to how the Greenland blocking index has been used to diagnose blocking, its trends, and impacts over the Arctic. |
| Silvopastoralism and the shaping of forest patches in the Atacama Desert during the Formative Period (ca. 3000–1500 years BP) | The Holocene | McRostie, V.; Babot, P.; Calás, E.; Gayó, E.; Gallardo, F.; Godoy-Aguirre, C.; Labarca, R.; Latorre, C.; Núñez, L.; Ojeda, K.; Santoro, C.; Valenzuela, D. | 2022 | Ciudades Resilientes | 10.1177/09596836221122636 | http://journals.sagepub.com/doi/10.1177/09596836221122636 | 1492-1502 | Vol: 32 Issue: 12 | 0959-6836, 1477-0911 | Thomson Reuters ISI (SCIE) | English | During the Formative period by the Late-Holocene (ca. 3000–1500 BP), semi-sedentary and sedentary human occupations had emerged in the oases, salares, and riverine systems in the central depression (2400–1000 masl) of the Atacama Desert, northern Chile (19–25°S). This hyperarid core was marginally occupied during the post-Pleistocene and middle Holocene droughts. Settlement on these lower belts was accompanied by a rise in humidity, the introduction of Andean crops, flourishment of Prosopis spp. (algarrobo) forests, and increasing integration of domestic camelid caravans. Here, we explore lowland husbandry within risk-spreading strategies, focusing on silvopastoralism and endozoochory between camelids and algarrobos. Analysis of camelid coprolites from seven archeological sites located in the Pampa del Tamarugal, Loa River, and Salar de Atacama found intense grinding from camelid chewing and indicated a ruminal digestive system. Abundant macro and microremains in the form of tissues, phytoliths, crystals, cell structures, and others, were identified as Prosopis, Atriplex, Schoenoplectus, Distichlis, and Phragmites. We conclude that camelids were foraging for Prosopis, although the rather low number of entire seeds preserved in the coprolites leads us to think that these herbivores might not have been the main vectors for the spread and germination of algarrobos. More samples and interdisciplinary studies are needed to comprehend the complex socioecological web in the shaping of these forests and the management of the Atacama Desert landscapes. | |
| Fire Scars: remotely sensed historical burned area and fire severity in Chile between 1984-2018 | Miranda, A.; Mentler, R.; Moletto, I.; Alfaro, G.; Aliaga, L.; Balbontín, D.; Barraza, M.; Baumbach, Susanne; Calderón, Patricio; Cardenas, Fernando; Castillo, Ivan; Gonzalo, Contreras; de la Barra, Felipe; Galleguillos, Mauricio; Gonzalez, Mauro; Hormazabal, Carlos; Lara, Antonio; Mancilla, Ian; Mu... | 2022 | Cambio de Uso de Suelo | 10.1594/PANGAEA.941127 | https://doi.pangaea.de/10.1594/PANGAEA.941127 | Pangaea | Creative Commons Attribution 4.0 International | English | The Landscape Fire Scars Database for Chile makes publicly available for the first time a historical high-resolution (~30 m) burned area and fire severity product for the country. The georeferenced database is a multi-institutional effort containing information on more than 8,000 fires events between July 1984 and June 2018. Using Google Earth Engine (GEE), we reconstructed the fire scar area, perimeter, and severity for each fire. We also provide the Landsat mosaic image of pre- and post-fire events, including the NDVI and NBR indexes. In the related paper, we release the GEE code to reproduce our database or enable the international community to reconstruct another individual burned areas and fire severity data, with minimum input requirements. In the summary file is the list of reconstructed fire events. The identification number (ID) relates the initial information of the wildfires with fire scar and severity data. | ||||
| The Landscape Fire Scars Database: mapping historical burned area and fire severity in Chile | Earth System Science Data | Miranda, A.; Mentler, R.; Moletto-Lobos, Í.; Alfaro, G.; Aliaga, L.; Balbontín, D.; Barraza, M.; Baumbach, S.; Calderón, P.; Cárdenas, F.; Castillo, I.; Contreras, G.; de la Barra, F.; Galleguillos, M.; González, M.; Hormazábal, C.; Lara, A.; Mancilla, I.; Muñoz, F.; Oyarce, C.; Pantoja, F.; Ramírez... | 2022 | Cambio de Uso de Suelo | 10.5194/essd-14-3599-2022 | https://essd.copernicus.org/articles/14/3599/2022/ | 3599-3613 | Vol: 14 Issue: 8 | 1866-3516 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract. Achieving a local understanding of fire regimes requires high-resolution, systematic and dynamic databases. High-quality information can help to transform evidence into decision-making in the context of rapidly changing landscapes, particularly considering that geographical and temporal patterns of fire regimes and their trends vary locally over time. Global fire scar products at low spatial resolutions are available, but high-resolution wildfire data, especially for developing countries, are still lacking. Taking advantage of the Google Earth Engine (GEE) big-data analysis platform, we developed a flexible workflow to reconstruct individual burned areas and derive fire severity estimates for all reported fires. We tested our approach for historical wildfires in Chile. The result is the Landscape Fire Scars Database, a detailed and dynamic database that reconstructs 8153 fires scars, representing 66.6 % of the country's officially recorded fires between 1985 and 2018. For each fire event, the database contains the following information: (i) the Landsat mosaic of pre- and post-fire images; (ii) the fire scar in binary format; (iii) the remotely sensed estimated fire indexes (the normalized burned ratio, NBR, and the relative delta normalized burn ratio, RdNBR); and two vector files indicating (iv) the fire scar perimeter and (v) the fire scar severity reclassification, respectively. The Landscape Fire Scars Database for Chile and GEE script (JavaScript) are publicly available. The framework developed for the database can be applied anywhere in the world, with the only requirement being its adaptation to local factors such as data availability, fire regimes, land cover or land cover dynamics, vegetation recovery, and cloud cover. The Landscape Fire Scars Database for Chile is publicly available in https://doi.org/10.1594/PANGAEA.941127 (Miranda et al., 2022). |
| Direct effects of tephra fallout from the Puyehue–Cordón Caulle Volcanic Complex on Nothofagus pumilio ring widths in northern Patagonia | Dendrochronologia | Montiel, M.; González, M.; Christie, D.; Muñoz, A.; Crisafulli, C. | 2022 | Agua y Extremos; Cambio de Uso de Suelo | 10.1016/j.dendro.2022.125998 | https://linkinghub.elsevier.com/retrieve/pii/S1125786522000789 | 125998 | Vol: 75 | 11257865 | Thomson Reuters ISI (SCIE) | English | We evaluated the radial growth response of adult Nothofagus pumilio (Poepp. et Endl) Krasser trees affected by tephra deposition following historical volcanic eruptions of the Puyehue–Cordón Caulle Volcanic Complex (PCCVC) in northern Patagonia. Standard tree–ring width chronologies were developed for trees from two sites that were affected by up to 55 cm of tephra during the 2011 eruption, which allowed us to detect the general tree–growth response to eruptions VEI ≥ 3 and VEI ≤ 2. The tree growth trend satisfactorily followed the mean temperature record (r = 0.42); however, the analysis of studentized residuals identified outliers (≥ ± 2 SD) directly related to the volcanic eruptions of the years 1921–1922 and 2011 and the respective post–eruption years, while for the 1960 eruption and following year, they largely exceeded the mean value of the residuals. The large amount of tephra deposited during the 1921–22 and 2011 eruptions caused physical damage to the tree canopy leading to the appearance of white rings and to locally absent rings. The rate of change in radial growth of trees during these eruptions presented significant declines in relation to the growth of five years before the eruption and to the following year. The low amount of tephra deposited during the 1960 eruption did not cause damage to the stands and trees increased their radial growth. In general, trees that had reduced radial growth experienced a remarkable recovery starting in the second or third post–eruption year. The amount of tephra deposited and the time of year of the volcanic eruptions had an important influence on tree rings. Some ecophysiological causes that could explain the growth responses of N. pumilio to tephra fall are discussed herein. Our study may provide useful insights to clarify the uncertain characteristics of some eruptions in the past or to detect the occurrence of large, undocumented volcanic eruptions throughout the Andes. © 2022 Elsevier GmbH | |
| Una nueva era del derecho ambiental: La Ley Marco de Cambio Climático en Chile a 50 años de Estocolmo | Revista de Derecho Ambiental | Moraga Sariego, P. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.5354/0719-4633.2022.67640 | https://revistaderechoambiental.uchile.cl/index.php/RDA/article/view/67640 | 1-8 | Vol: 1 Issue: 17 | 0719-4633, 0718-0101 | Scopus | https://creativecommons.org/licenses/by-sa/4.0/deed.es | ||
| El aporte jurisprudencial de los Tribunales Ambientales chilenos en materia de reparación del daño ambiental | Ius et Praxis | Moraga Sariego, P.; Delgado Schneider, V. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.4067/S0718-00122022000200286 | https://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-00122022000200286&lng=en&nrm=iso&tlng=en | 286-301 | Vol: 28 Issue: 2 | 0718-0012 | SciELO; Scopus | All Open Access; Gold Open Access | English | The Law of General Bases of the Environment introduced environmental liability in Chilean legislation and to two actions (remediation and penalty). In the nineties, the Ordinary Courts of Justice were competent to hear both actions. However, after the environmental reform and the Environmental Courts creation (2012), these Tribunals have been in charge to hear the environmental remediation claims. This change would have meant, in our opinion, a further development of this institution in a more protective sense of the environment, where what the doctrine has attributed to the specialized nature of environmental Courts, made up of lawyers and technical ministers. From now on, the environmental damage concept is amplified, which is contemplated in article 52 of Law 19,300. The legal and jurisprudential evolution greatest access to justice and the effectiveness of the reparation action for environmental damage. © 2022, Ius et Praxis. All Rights Reserved. |
| Fortalecimiento de capacidades a nivel subnacional: La experiencia de los Comités Regionales de Cambio Climático en Chile | Moraga, P.; Gonzalez, B.; Martinez, F. | 2022 | https://www.cr2.cl/fortalecimiento-de-capacidades-a-nivel-subnacional-la-experiencia-de-los-comites-regionales-de-cambio-climatico-en-chile/ | 17 | cr2.cl | Spanish | La presente publicación “Policy Brief: Fortalecimiento de capacidades a nivel subnacional. La experiencia de los Comités Regionales de Cambio Climático de Chile” ha sido elaborada en el marco de la ejecución de la acción “fortalecimiento institucional y de generación de capacidades a nivel subnacional en el contexto de la elaboración de la Estrategia climática de desarrollo resiliente y bajo en emisiones al 2050 para Chile”, liderado por el Ministerio de Medio Ambiente en alianza con el Programa EUROCLIMA+ e implementado a través de la Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) con el apoyo del Centro de Ciencia del Clima y la Resiliencia (CR)2. La presente publicación ha sido elaborada con el apoyo financiero de la Unión Europea. Su contenido es responsabilidad exclusiva de la autora y autores y no necesariamente refleja los puntos de vista de la Unión Europea Se autoriza la reproducción total o parcial del presente documento, sin fines comerciales, citando: Ministerio del Medio Ambiente (2022). Policy Brief: Fortalecimiento de capacidades a nivel subnacional. La experiencia de los Comités Regionales de Cambio Climático de Chile, Santiago, Chile. 17 p. | ||||||
| Boletín especial N° 2 | Orden público climático y ecológico: Principios, derechos y deberes constitucionales para la acción climática y ecológica | Moraga, P.; Hervé, D.; Pulgar, A.; Billi, M. | 2022 | https://www.cr2.cl/boletin-especial-n-2-orden-publico-climatico-y-ecologico-principios-derechos-y-deberes-constitucionales-para-la-accion-climatica-y-ecologica/ | 8 | cr2.cl | Spanish | El proceso constituyente en Chile implica la oportunidad histórica de incluir en la carta fundamental orientaciones para afrontar la actual crisis climática y ecológica que afecta al país. La Declaración de Emergencia Climática y Ecológica suscrita por 137 miembros de la Convención Constitucional el 4 de octubre de 2021, supone el diseño de un nuevo ordenamiento jurídico e institucional, que posibilite respuestas efectivas frente a las distintas mani- festaciones del cambio climático y los riesgos que este supone. La nueva Constitución debe generar un orden público que permita que los retos climáticos y ecológicos se integren de manera transversal en la sociedad chilena. Esto implica articular distintas categorías jurídicas en el nuevo texto constitucional acorde a la magnitud del desa- fío que enfrentamos. En este boletín proveemos insumos para la discusión y justificación de iniciativas constitucionales en esta direc- ción. Una presentación completa de las propuestas de (CR)2 en esta materia se encuentra aqui: Boletin especial: Cambio Climático y Nueva Constitución |
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| A Song of Wind and Ice: Increased Frequency of Marine Cold‐Spells in Southwestern Patagonia and Their Possible Effects on Giant Kelp Forests | Journal of Geophysical Research: Oceans | Mora‐Soto, A.; Aguirre, C.; Iriarte, J.; Palacios, M.; Macaya, E.; Macias‐Fauria, M. | 2022 | Zonas Costeras | 10.1029/2021JC017801 | https://onlinelibrary.wiley.com/doi/10.1029/2021JC017801 | arte2021JC017801 | Vol: 127 Issue: 6 | 2169-9275, 2169-9291 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | In contrast to other coastal regions of the world, the giant kelp (Macrocystis pyrifera) ecosystem in southwestern Patagonia has been persistent in area and associated biodiversity in the last decades. In this ecoregion, sea surface temperature (SST) records have consistently remained below the upper thermal threshold for kelp survival, however, no studies have analyzed the spatiotemporal variability of SSTs and their anomalies across the geographical diversity of the southwestern Patagonian coastline. We explored the geographical distribution of extreme warm and cold events in this region from latitudes 47°–56°S in a range of ∼1,000 km, identifying the dates and spatial distribution of marine heatwaves (MHWs) and marine cold-spells (MCSs) from 1982 to 2020. Results show that a peak in the number of MHWs occurred in the great El Niño year of 1998. Additionally, the 2014–2019 period has had more severe and extreme MCSs than the previous decades. We discuss the origin of these events with a focus on three main processes: (a) geographically constrained cold events caused by glacier melting, (b) regional cold events caused by extreme winds linked to the position of the polar front, and (c) extensive SST anomalies linked to planetary-scale events such as El Niño and La Niña. Overall, those processes were conductive to counteract global warming trends locally/regionally, highlighting southwestern Patagonia as a possible climatic refugium for the giant kelp ecosystem. Despite this, the effects of freshwater inputs and storm turbulence on the exposed coasts facing the Southern Ocean may cause new kinds of stress on this ecosystem. © 2022. The Authors. |
| Glacier and terrestrial ecosystem evolution in the Chilotan archipelago sector of northwestern Patagonia since the Last Glacial Termination | Earth-Science Reviews | Moreno, P.; Fercovic, E.; Soteres, R.; Ugalde, P.; Sagredo, E.; Villa-Martínez, R. | 2022 | Agua y Extremos | 10.1016/j.earscirev.2022.104240 | https://linkinghub.elsevier.com/retrieve/pii/S0012825222003245 | 104240 | Vol: 235 | 0012-8252 | Thomson Reuters ISI (SCIE) | English | We examine the glacier, terrestrial ecosystem, and climate evolution since the Last Glacial Termination (T1) based on glacial sediments/landform assemblages and palynological data from the Chilotan archipelago (41°30′S-43°30′S), northwestern Patagonia. Deglacial warming drove recession of the Golfo Corcovado glacier lobe from the Last Glacial Maximum moraines in the interior of Isla Grande de Chiloé (IGC) before ∼17.8 ka, along with a rapid and irreversible trend toward arboreal dominance. Subsequent glacier stabilization led to deposition of the innermost moraines in eastern IGC and adjacent islands sometime between ∼17.5–16.9 ka, followed by an acceleration in glacial retreat that vacated the Chilotan Interior Sea in ∼200 years or less. Early successional cold-tolerant shade-intolerant trees prevailed during the initial stages of T1, followed by temperate rainforests dominated by thermophilous shade-tolerant species between ∼15–14.5 ka. A mixed forest with cold-tolerant hygrophilous conifers established between ∼14.5–12.6 ka, implying cooler climate and stronger Southern Westerly Wind (SWW) influence during the Antarctic Cold Reversal. Stand-replacing fires favored early successional shade-intolerant trees, shrubs, and herbs between ∼12.6–10.8 ka in response to milder temperatures and weaker SWW during Younger Dryas time. The early Holocene (∼10.8–7.5 ka) features a maximum in shade-intolerant thermophilous trees, absence of conifers, and peak fire activity, signaling a warm/dry interval with minimum SWW influence. Cooler/wetter conditions have prevailed over the last ∼7500 years driven by strong SWW influence. We conclude that Patagonian glaciers and terrestrial ecosystems responded simultaneously to climate changes at regional, hemispheric, and global scales multiple times since T1. We adhere to the concept that millennial-scale variations in the SWW linked the response of the hydro- bio and cryosphere across the southern mid- and high southern latitudes, and were teleconnected with northern hemisphere events through the atmospheric concentration of greenhouse gases, latitudinal shifts in the Intertropical convergence zone, and deep ocean circulation. © 2022 Elsevier B.V. | |
| Examining the potential of Austrocedrus chilensis tree rings as indicators of past late-spring frost events in central Chile | Dendrochronologia | Muñoz-Salazar, T.; LeQuesne, C.; Rozas, V.; Christie, D.; Rojas-Badilla, M. | 2022 | Agua y Extremos | 10.1016/j.dendro.2022.125962 | https://linkinghub.elsevier.com/retrieve/pii/S112578652200042X | 125962 | Vol: 74 | 11257865 | Thomson Reuters ISI (SCIE) | English | Austrocedrus chilensis is a South American conifer broadly distributed across the subtropical and extratropical Andes that is widely utilized in tree-ring studies. This species has clear annual growth rings that are sensitive to the moisture supply and has been extensively used to reconstruct the past hydroclimate during the last millennium. Despite a great number of dendrochronological studies based on tree-ring width, little is known about the potential of the species to record intra-annual anomalies and particularly frost rings. In this study, the main traits of A. chilensis frost rings were studied and the ability of this endemic Cupressaceae to record spring frosts at five sites across a latitudinal gradient between the Mediterranean and Northern Patagonian Andes was evaluated. The average ages of trees in the study sites varied from 168 to 343 years, with minimum and maximum ages of 33 and 919 years. The results indicated that 85% of the frost rings occurred at the beginning of the earlywood and 15% showed a mid intra-ring position. Regarding the portion of the ring circumference affected by frost damage in cross sections, 59% of the injuries partially affected the entire ring, 30% affected the complete ring circumference, and 11% resulted in a ring fracture. Freezing temperatures that generated frost rings in A. chilensis from the upper treeline coincided with events below 0 °C recorded in the agricultural Central Valley of Chile. We estimated the potential time window of the formation of A. chilensis frost rings over a two and a half month period from the end of September to mid-November (early spring). Our results indicated that tree age was a determinant factor affecting the ability of trees to record frost rings. The maximum frequency of frost rings occurred at 12 years and the maximum age at which 95% of the total frost injuries occurred within our network was about 120 years. Both the exceptional longevity and the excellent state of preservation of relict wood demonstrates that A. chilensis frost rings provide a reliable proxy for monitoring and reconstructing late-spring frost events in central Chile. © 2022 Elsevier GmbH | |
| Characterization and genomic analysis of two novel psychrotolerant Acidithiobacillus ferrooxidans strains from polar and subpolar environments | Frontiers in Microbiology | Muñoz-Villagrán, C.; Grossolli-Gálvez, J.; Acevedo-Arbunic, J.; Valenzuela, X.; Ferrer, A.; Díez, B.; Levicán, G. | 2022 | Zonas Costeras | 10.3389/fmicb.2022.960324 | https://www.frontiersin.org/articles/10.3389/fmicb.2022.960324/full | 960324 | Vol: 13 | 1664-302X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The bioleaching process is carried out by aerobic acidophilic iron-oxidizing bacteria that are mainly mesophilic or moderately thermophilic. However, many mining sites are located in areas where the mean temperature is lower than the optimal growth temperature of these microorganisms. In this work, we report the obtaining and characterization of two psychrotolerant bioleaching bacterial strains from low-temperature sites that included an abandoned mine site in Chilean Patagonia (PG05) and an acid rock drainage in Marian Cove, King George Island in Antarctic (MC2.2). The PG05 and MC2.2 strains showed significant iron-oxidation activity and grew optimally at 20°C. Genome sequence analyses showed chromosomes of 2.76 and 2.84 Mbp for PG05 and MC2.2, respectively, and an average nucleotide identity estimation indicated that both strains clustered with the acidophilic iron-oxidizing bacterium Acidithiobacillus ferrooxidans . The Patagonian PG05 strain had a high content of genes coding for tolerance to metals such as lead, zinc, and copper. Concordantly, electron microscopy revealed the intracellular presence of polyphosphate-like granules, likely involved in tolerance to metals and other stress conditions. The Antarctic MC2.2 strain showed a high dosage of genes for mercury resistance and low temperature adaptation. This report of cold-adapted cultures of the At. ferrooxidans species opens novel perspectives to satisfy the current challenges of the metal bioleaching industry. |
| Using Commercial Aircraft Meteorological Data to Assess the Heat Budget of the Convective Boundary Layer Over the Santiago Valley in Central Chile | Boundary-Layer Meteorology | MuñozR, R.; Whiteman, C.; Garreaud, R.; Rutllant, J.; Hidalgo, J. | 2022 | Agua y Extremos | 10.1007/s10546-021-00685-3 | https://link.springer.com/10.1007/s10546-021-00685-3 | 295-319 | Vol: 183 Issue: 2 | 0006-8314, 1573-1472 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The World Meteorological Organization Aircraft Meteorological Data Relay (AMDAR) programme refers to meteorological data gathered by commercial aircraft and made available to weather services. It has become a major source of upper-air observations whose assimilation into global models has greatly improved their performance. Near busy airports, AMDAR data generate semi-continuous vertical profiles of temperature and winds, which have been utilized to produce climatologies of atmospheric-boundary-layer (ABL) heights and general characterizations of specific cases. We analyze 2017–2019 AMDAR data for Santiago airport, located in the centre of a $$40\times 100$$ 40 × 100 km $$^2$$ 2 subtropical semi-arid valley in central Chile, at the foothills of the Andes. Profiles derived from AMDAR data are characterized and validated against occasional radiosondes launched in the valley and compared with routine operational radiosondes and with reanalysis data. The cold-season climatology of AMDAR temperatures reveals a deep nocturnal inversion reaching up to 700 m above ground level (a.g.l.) and daytime warming extending up to 1000 m a.g.l. Convective-boundary-layer (CBL) heights are estimated based on AMDAR profiles and the daytime heat budget of the CBL is assessed. The CBL warming variability is well explained by the surface sensible heat flux estimated with sonic anemometer measurements at one site, provided advection of the cool coastal ABL existing to the west is included. However, the CBL warming accounts for just half of the mean daytime warming of the lower troposphere, suggesting that rather intense climatological diurnal subsidence affects the dynamics of the daytime valley ABL. Possible sources of this subsidence are discussed. |
| Ensuring access to water in an emergency context: Towards an overexploitation and contamination of water resources? | Social & Legal Studies | Nicolas-Artero, C. | 2022 | Agua y Extremos | 10.1177/09646639211031626 | http://journals.sagepub.com/doi/10.1177/09646639211031626 | 459-476 | Vol: 31 Issue: 3 | 1461-7390 | Thomson Reuters ISI (SSCI) | English | This article shows how geo-legal devices created to deal with environmental crisis situations make access to drinking water precarious and contribute to the overexploitation and contamination of water resources. It relies on qualitative methods (interviews, observations, archive work) to identify and analyse two geo-legal devices applied in the case study of the Elqui Valley in Chile. The first device, generated by the Declaration of Water Scarcity, allows private sanitation companies to concentrate water rights and extend their supply network, thus producing an overexploitation of water resources. In the context of mining pollution, the second device is structured around the implementation of the Rural Drinking Water Programme and the distribution of water by tankers, which has made access to drinking water more precarious for the population and does nothing to prevent pollution. | |
| Les marges hydriques au Chili : une imbrication entre l’espace et les règles institutionnelles de l’eau | Géocarrefour | Nicolas-Artero, C. | 2022 | 10.4000/geocarrefour.19805 | http://journals.openedition.org/geocarrefour/19805 | 1-21 | Vol: 96 Issue: 1 | 1627-4873, 1960-601X | Not indexed | French | This paper studies the effects of the spread of monoculture on the irrigated systems of a semiarid valley in Chile. From legal geography, it proposes the notion of a fluvial geo-legal system to analyze the relationships between political economy, institutional rules of water and space. The ethnographic approach adopted reveals water margins, produced by the existence of a plural economy, represented by family or subsistence agriculture, whose water supply is based on preexisting irrigation practices. These margins are crossed by power relationships around the appropriation of space and water which crystallize in the seizure of institutional water rules. Their existence nuances the progress of an extractive frontier, the local effects of the Water Code and the modernization of techniques and conceptions of water. © 2022 Geocarrefour. All rights reserved. | ||
| De l’usage du droit dans les résistances paysannes au Chili | Cahiers d'Outre-Mer | Nicolas-Artero, C. | 2022 | 10.4000/com.13654 | http://journals.openedition.org/com/13654 | 53-85 | Vol: LXXV Issue: 285 | 0373-5834, 1961-8603 | DOAJ | ||||
| Modes of access to water for domestic use in rural Chile: a typological proposal | Water Policy | Nicolas-Artero, C.; Blanco, G.; Bopp, C.; Carrasco, N. | 2022 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | 10.2166/wp.2022.026 | https://iwaponline.com/wp/article/24/7/1179/89257/Modes-of-access-to-water-for-domestic-use-in-rural | 1179-1194 | Vol: 24 Issue: 7 | 1366-7017, 1996-9759 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | A typology is proposed regarding the modes of access to water for the rural population in Chile as well as four explanatory dimensions of its heterogeneity. The typology emerges from a systematic review of the literature and an analysis of quantitative data based on rural water organizations' databases. The modes of access are defined by the following five criteria: their socio-technical system, their type of management, their level of spatial action, the source of their financing, and the type of technical assistance they received. The findings dispute the systemic vision of access to water in rural areas and invite us to consider the structural heterogeneity in regulations and public policies to guarantee the human right to water. |
| Generalised seed mortality driven by heat shock in woody plants from Mediterranean Chile | International Journal of Wildland Fire | Ocampo-Zuleta, K.; Gómez-González, S.; Paula, S. | 2022 | Cambio de Uso de Suelo | 10.1071/WF22027 | https://www.publish.csiro.au/WF/WF22027 | 1080-1088 | Vol: 31 Issue: 11 | 1049-8001, 1448-5516 | Thomson Reuters ISI (SCIE) | English | Background Wildfires have shaped plant traits and ecosystems worldwide. Most research on the relevance of fire on plant evolution comes from Mediterranean-type ecosystems (MTEs), where a great proportion of the studied species have fire-stimulated germination. However, seed fire ecology is widely unknown for the woody flora of the Chilean matorral, the only MTE where natural fires are infrequent owing to the scarcity of non-anthropogenic ignition sources. Aim The study aimed to evaluate whether seed sensitivity to heat is generalised among the woody species of the matorral. Methods We performed heat shock experiments on the seeds of 21 woody plant species not previously assessed. These species and those from previous studies were classified according to their response as stimulated, tolerant and inhibited. The preponderance of any of these categories was statistically evaluated. Key results Exposure to 100°C for 5 min significantly decreased seed survival in all studied species. Conclusions Seed persistence to fire is less common than previously reported among woody plants from the Chilean MTE. Implications Increased wildfire events in the future may erode the genetic diversity of the Chilean flora. Germplasm banks may become crucial in post-fire restoration programs in this ecoregion, where the landscape has become increasingly flammable. | |
| Water dynamics over a Western Patagonian watershed: Land surface changes and human factors | Science of The Total Environment | Olivera-Guerra, L.; Quintanilla, M.; Moletto-Lobos, I.; Pichuante, E.; Zamorano-Elgueta, C.; Mattar, C. | 2022 | Cambio de Uso de Suelo | 10.1016/j.scitotenv.2021.150221 | https://linkinghub.elsevier.com/retrieve/pii/S0048969721052980 | 150221 | Vol: 804 | 00489697 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Warming trends in Patagonia and severe droughts in recent decades are still poorly understood in terms of their hydrological effects. The effects of climate change on water dynamics in addition to human water management could generate a future water scarcity scenario in one of the regions with the most abundant water resources of Chile. The aim of this work is to focus on assessing the impacts of warming trends on water dynamics in the Patagonian Simpson River watershed during the last two decades. We estimated anomalies in the main components of water balance such as precipitation (P), snow cover (SC), evapotranspiration (ET) and streamflows (Q) as well as surface variables and meteorological forcing (i.e. air temperature - Ta, solar radiation - RS, land surface temperature - LST). The processed data were obtained from remote sensing, reanalysis and in-situ data. We implemented a trend analysis for each variable in the period 2000-2019 at monthly, seasonal and annual scale. Results showed a warming trend in Ta and LST of about 1.2 °C and 2.1 °C, respectively, concentrated mainly in the autumn and winter seasons. Although P showed non-significant trends, Q diminished significantly at rates of more than 9.1 m3/s/decade, representing 36% of its historical mean. However, the decreases in Q are seen only in the maximum (spring) and minimum (summer) seasonal flows. These decreases are explained by significant increases in ET, led by a positive feedback of its drivers (LST, Ta and RS), which is directly linked to the impact of warming and an associated vegetation greenness in the watershed, as well as a decrease in SC during winter that feeds the Simpson River during spring and summer. The decrease in Q is reinforced by the intensification of water withdrawals in recent decades, as shown by an accelerated increase in water rights for agricultural and drinking uses. In a context of water scarcity and increasing and extreme droughts, this work contributes to further understanding water dynamics in western Patagonia, providing support for policy and decision-making when defining sustainable productive practices at watershed scale. |
| Transporte público eléctrico en Valparaíso y Medellín: Historias de movilidad intermodal sobre las que construir el futuro | Estudios de Transporte | Osses, M.; Ibarra, C.; Vila, W. | 2022 | https://estudiosdetransporte.org/sochitran/article/view/266 | 1-19 | Vol: 23 Issue: 1 | 2735-6299 | Latindex | Spanish | Este trabajo hace un recorrido histórico por las diversas formas de transporte público eléctrico de Valparaíso, que incluye ascensores, tranvías, trolebuses, tren y metro, y que se inició hace más de un siglo. Esta experiencia se compara con la de Medellín, Colombia, que es un ejemplo moderno de transporte público eléctrico multimodal, y que también tiene una historia relevante. Se plantea como hipótesis que una diferencia fundamental entre ambos sistemas está en la gobernanza de la planificación urbana y que la experiencia comparada inspira reflexiones para el futuro de la electromovilidad en Chile. Se establecen relaciones entre el transporte público, los procesos de planificación urbana y la participación de los vehículos eléctricos en la movilidad de Valparaíso y Medellín. Esta comparación muestra que los vehículos eléctricos son parte de la historia de estas ciudades, se adaptan a geografías irregulares y escarpadas, tienen un alto nivel de aceptación por parte de la población y, con procesos de planificación urbana integrales, pueden constituir una solución sustentable para la movilidad del futuro. | |||
| High-resolution spatial-distribution maps of road transport exhaust emissions in Chile, 1990–2020 | Earth System Science Data | Osses, M.; Rojas, N.; Ibarra, C.; Valdebenito, V.; Laengle, I.; Pantoja, N.; Osses, D.; Basoa, K.; Tolvett, S.; Huneeus, N.; Gallardo, L.; Gómez, B. | 2022 | Ciudades Resilientes | 10.5194/essd-14-1359-2022 | https://essd.copernicus.org/articles/14/1359/2022/ | 1359-1376 | Vol: 14 Issue: 3 | 1866-3508 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Abstract. This description paper presents a detailed and consistent estimate and analysis of exhaust pollutant emissions generated by Chile's road transport activity for the period 1990–2020. The complete database for the period 1990–2020 is available at the following DOI: https://doi.org/10.17632/z69m8xm843.2 (Osses et al., 2021). Emissions are provided at a high spatial resolution (0.01∘ × 0.01∘) over continental Chile from 18.5 to 53.2∘ S, including local pollutants (CO; volatile organic compounds, VOCs; NOx; PM2.5), black carbon (BC) and greenhouse gases (CO2, CH4). The methodology considers 70 vehicle types, based on 10 vehicle categories, subdivided into 2 fuel types and 7 emission standards. Vehicle activity was calculated based on official databases of vehicle records and vehicle flow counts. Fuel consumption was calculated based on vehicle activity and contrasted with fuel sales to calibrate the initial dataset. Emission factors come mainly from the Computer programme to calculate emissions from road transport version 5 (COPERT 5), adapted to local conditions in the 15 political regions of Chile, based on emission standards and fuel quality. While vehicle fleet grew 5-fold between 1990 and 2020, CO2 emissions have followed this trend at a lower rate, and emissions of air local pollutants have decreased due to stricter abatement technologies, better fuel quality and enforcement of emission standards. In other words, there has been decoupling between fleet growth and emissions' rate of change. Results were contrasted with global datasets (EDGAR, CAMS, CEDS), showing similarities in CO2 estimations and striking differences in PM, BC and CO; in the case of NOx and CH4 there is coincidence only until 2008. In all cases of divergent results, global datasets estimate higher emissions. |
| Upwelled plankton community modulates surface bloom succession and nutrient availability in a natural plankton assemblage | Biogeosciences | Paul, A.; Bach, L.; Arístegui, J.; von der Esch, E.; Hernández-Hernández, N.; Piiparinen, J.; Ramajo, L.; Spilling, K.; Riebesell, U. | 2022 | Zonas Costeras | 10.5194/bg-19-5911-2022 | https://bg.copernicus.org/articles/19/5911/2022/ | 5911-5926 | Vol: 19 Issue: 24 | 1726-4189 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract. Upwelling of nutrient-rich waters into the sunlit surface layer of the ocean supports high primary productivity in eastern boundary upwelling systems (EBUSs). However, subsurface waters contain not only macronutrients (N, P, Si) but also micronutrients, organic matter and seed microbial communities that may modify the response to macronutrient inputs via upwelling. These additional factors are often neglected when investigating upwelling impacts on surface ocean productivity. Here, we investigated how different components of upwelled water (macronutrients, organic nutrients and seed communities) drive the response of surface plankton communities to upwelling in the Peruvian coastal zone. Results from our short-term (10 d) study show that the most influential drivers in upwelled deep water are (1) the ratio of inorganic nutrients (NOx : PO43-) and (2) the microbial community present that can seed heterogeneity in phytoplankton succession and modify the stoichiometry of residual inorganic nutrients after phytoplankton blooms. Hence, this study suggests that phytoplankton succession after upwelling is modified by factors other than the physical supply of inorganic nutrients. This would likely affect trophic transfer and overall productivity in these highly fertile marine ecosystems. |
| Irrigation management or climate change ? Which is more important to cope with water shortage in the production of table grape in a Mediterranean context | Agricultural Water Management | Pizarro, E.; Galleguillos, M.; Barría, P.; Callejas, R. | 2022 | Cambio de Uso de Suelo | 10.1016/j.agwat.2022.107467 | https://linkinghub.elsevier.com/retrieve/pii/S0378377422000142 | 107467 | Vol: 263 | 0378-3774 | Thomson Reuters ISI (SCIE) | English | Table grape production requires large amount of water, which can be problematic in semi-arid Mediterranean regions, where climate change projections anticipated reductions in water availability associated to decreases in precipitation and increases in temperature. In this context, this study aims to evaluate the effect of contrasting irrigation strategies and climate change scenarios on key water balance variables using a Chilean Table grape crop as case study. A standard and an improved irrigation management treatments were implemented in situ during the 2015/2016 and the 2016/2017–2017/2018 observed growing seasons, respectively. Then, the HYDRUS-1D water transfer model was run to simulate the three observed growing seasons and 27 near future growing seasons (2019/2020–2044/2015) under climate change conditions. Satisfactory calibration and validation results against soil moisture and water storage measurements were obtained within the first and the second observed growing seasons respectively (RRMSE values below 5%). Results during the observed seasons showed that by changing the standard irrigation by the improved irrigation management, the water use efficiency (WUEi) increases from 49.5% to 55.7%. For the near future, the calibrated model shows that under all the tested climate change scenarios, irrigation strategies based on supplying 80% and 50% of the crop evapotranspiration (ETc) (deficit irrigation scenarios) have larger efficiencies compared to the standard irrigation management (presenting a higher actual basal crop coefficient and lower percolation). Similar results were obtained under future extreme climate change years, defined as the ratio between model-based projections of reference evapotranspiration (ET0) and precipitation, with the deficit irrigation scenarios having larger efficiencies than the standard irrigation management. Based on these results, it is concluded that by mid- century, the irrigation management has more relevance than climate change impacts for tables grapes growing under a Mediterranean climate in central Chile. © 2022 | |
| Assessing the socio-economic and land-cover drivers of wildfire activity and its spatiotemporal distribution in south-central Chile | Science of The Total Environment | Pozo, R.; Galleguillos, M.; González, M.; Vásquez, F.; Arriagada, R. | 2022 | Cambio de Uso de Suelo | 10.1016/j.scitotenv.2021.152002 | https://linkinghub.elsevier.com/retrieve/pii/S0048969721070789 | 152002 | Vol: 810 | 00489697 | Thomson Reuters ISI (SCIE) | English | Sustained human pressures on the environment have significantly increased the frequency, extent, and severity of wildfires, globally. This is particularly the case in Mediterranean regions, in which human-caused wildfires represent up to 90% of all recorded wildfire ignitions. In Chile, it has been estimated that nearly 90% of wildfires are related to human activities, and that their frequency and distribution have steadily increased over the last decade. Despite this, the role of socio-economic factors in driving wildfire activity and its spatiotemporal distribution remains unclear. In this study, we assess the association between socio-economic drivers and spatiotemporal patterns of wildfires in the Mediterranean region of south-central Chile over the period 2010–2018. Our results show that 98.5% of wildfires are related to human activities, either accidentally (58.2%) or intentionally (36.6%). Wildfires occurred primarily during the summer months and their density at the commune-level was associated with increased road access, as well as with the percentage of land covered by agriculture, exotic tree plantations, and native forest. Wildfire activity at the commune-level was also related to socio-economic variables such as population density, proportion of indigenous population, and unemployment rate, although such associations varied considerably depending on the region and on whether the wildfire was started accidentally or intentionally. Our study provides a comprehensive and interdisciplinary assessment of the complex ways in which land-cover and socio-economic factors drive the distribution of wildfire activity in south-central Chile. It represents an important guide for policy-making, as well a baseline for research into strategies aimed at predicting and mitigating wildfire activity at both local and national levels. | |
| Chlorine-36 Surface Exposure Dating of Late Holocene Moraines and Glacial Mass Balance Modeling, Monte Sierra Nevada, South-Central Chilean Andes (38°S) | Frontiers in Earth Science | Price, B.; Stansell, N.; Fernández, A.; Licciardi, J.; Lesnek, A.; Muñoz, A.; Sorensen, M.; Jaque Castillo, E.; Shutkin, T.; Ciocca, I.; Galilea, I. | 2022 | Agua y Extremos | 10.3389/feart.2022.848652 | https://www.frontiersin.org/articles/10.3389/feart.2022.848652/full | 848652 | Vol: 10 | 2296-6463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The development of robust chronologies of Neoglaciation from individual glaciers throughout the high-altitude Andes can provide fundamental knowledge of influences such as regional temperature and precipitation variability, and aid in predicting future changes in the Andean climate system. However, records of Late Holocene glaciation from the Central Chilean Andes are sparse, and often poorly constrained. Here, we present 36 Cl surface exposure ages, dendrochronologic constraints, and glacial mass balance modeling simulations of Late Holocene glacier fluctuations in the Central-South Chilean Andes. A series of concentric moraine ridges were identified on Monte Sierra Nevada (38°S), where exposure dating of basaltic boulders was used to establish a chronology of ice recession. We infer that moraine abandonment of the most distal ridge in the valley commenced by ∼4.2 ka, and was followed by glacier margin retreat to an up-valley position. Exposure ages of the oldest Late Holocene boulders (∼2.5–0.8 ka) along the marginal extents of the moraine complex indicate fluctuations of the glacier terminus prior to ∼0.65 ka. A final expansion of the ice margin reoccupied the position of the 4.2 ka moraine, with abatement from the outermost composite moraine occurring by ∼0.70 ka, as constrained by tree-ring data from live Araucaria araucana trees. Finally, a series of nested moraines dating to ∼0.45–0.30 ka, formed from a pulsed ice recession during the latest Holocene when the lower reaches of the glacial snout was most likely debris mantled. A distributed temperature index model combined with a glacier flow model was used to quantify an envelope of possible climatic conditions of Late Holocene glaciation. The glacial modeling results suggest conditions were ∼1.5°C colder and 20% wetter during peak Neoglaciation relative to modern conditions. These records also suggest a near-coeval record of Late Holocene climate variability between the middle and high southern latitudes. Furthermore, this study presents some of the youngest 36 Cl exposure ages reported for moraines in the Andes, further supporting this method as a valuable geochronologic tool for assessing Late Holocene landscape development. |
| Coping Strategies and Tactics to Deal With Social Vulnerability in the Flood Disaster of March 25, 2015, in Chañaral and Diego de Almagro, Chile | Frontiers in Climate | Pérez Tello, S.; Aldunce Ide, P.; Flores-Haverbeck, F.; Mena Maldonado, D.; Castro Correa, C.; Wyndham Vásquez, K. | 2022 | Agua y Extremos | 10.3389/fclim.2022.763413 | https://doi.org/10.3389/fclim.2022.763413 | art: 763413 | Vol: 4 | 2624-9553 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | A socio-natural disaster event exacerbates pre-existing socio-economic crises and disrupts the life projects of the people affected, generating the deployment of strategic or tactical actions to deal with it. When societies have populations living in conditions of social vulnerability prior to disasters, such actions are more complex and difficult to manage. On March 25, 2015 (25M), the inhabitants of the towns of Chañaral and Diego de Almagro, in the Atacama Region of Chile, were faced with a flood that produced a crisis of great magnitude. This qualitative research describes the actions the inhabitants used to reduce social vulnerability, before, during and after the emergency. These actions were analyzed to describe the extent of planning, meanings, resources and structures of opportunities present in the actions. Content analysis was carried out on semi-structured interviews with 38 affected people, selected using intentional sampling technique together with snowball sampling. Subjective resources were identified: sense of family, solidarity, autonomy and restitution of rights. The superimposed mobilization of these resources resulted in a complex situation of resilience. It is concluded that the way of learning actions includes family and cultural habits, daily learning and previous experiences, and imitation, among others. Recommendations are made to be considered for the reduction of risks of socio-natural disasters. Specifically, policies that include educational strategies that are based on theways of acting shown by the communities. Copyright © 2022 Pérez Tello, Aldunce Ide, Flores-Haverbeck, Mena Maldonado, Castro Correa and Wyndham Vásquez. |
| Size matters: Physiological sensitivity of the scallop Argopecten purpuratus to seasonal cooling and deoxygenation upwelling-driven events | Frontiers in Marine Science | Ramajo, L.; Sola-Hidalgo, C.; Valladares, M.; Astudillo, O.; Inostroza, J. | 2022 | Zonas Costeras | 10.3389/fmars.2022.992319 | https://www.frontiersin.org/articles/10.3389/fmars.2022.992319/full | 992319 | Vol: 9 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Environment imposes physiological constraints which are life-stage specific as growth-maintenance and/or growth-reproduction energetic requirements are size and volume-dependent. The scallop Argopecten purpuratus , one of the most important bivalve species subjected to fishery and aquaculture along the Humboldt Current System, inhabits spaces affected by continuous changes in temperature, pH, oxygen, and food availability driven by remote and local oceanographic processes. Specifically, in Chile, this species is mainly cultured in central-north Chile where is permanently affected by upwelling events of dissimilar intensity and duration which generate local conditions of acidification, deoxygenation, and cooling with different magnitudes. However, to date, it remains unknown how this economic valuable resource is physiologically affected throughout its life cycle by the continuous environmental changes driven by upwelling events of different intensities and duration along the year. Here, for the first time, A. purpuratus life-stage physiological sensitivity was assessed at a seasonal scale through a year-field experiment where growth, calcification, and survivorship were evaluated. Our study shows how seasonal differences in the upwelling phenology (here measured as changes in temperature, dissolved oxygen, pH, and primary productivity, but also as the number, duration, and intensity of cooling and de-oxygenation events) notably impacted the A. purpuratus physiological performance from juvenile to adult life-stages. This was especially noticeable during the spring season which showed the most intense cooling and deoxygenation events driven by stronger favorable-upwelling winds and the lowest growth and gross calcification rates (the highest decalcification rates) where adult stages showed the lowest performance. On the other hand, A. purpuratus survivorship was not significantly affected by upwelling intensity which would be providing evidence of the high physiological flexibility and well-locally adapted is this species to fluctuating and occasional stressful environmental conditions. Our results are significantly relevant in the climate change context as some upwelling systems are at risk to change shortly (i.e., an upwelling intensification in frequency and intensity) as a consequence of changes in the atmospheric pressures that modulate favourable-upwelling winds. These changes may certainly increase the climate related-risks of the entire socio-ecological systems related to the fishery and aquaculture of A. purpuratus along the Humboldt Current System. |
| Microbial Biogeochemical Cycling of Nitrogen in Arid Ecosystems | Microbiology and Molecular Biology Reviews | Ramond, J.; Jordaan, K.; Díez, B.; Heinzelmann, S.; Cowan, D. | 2022 | Zonas Costeras | 10.1128/mmbr.00109-21 | https://journals.asm.org/doi/10.1128/mmbr.00109-21 | e00109-21 | Vol: 86 Issue: 2 | 1092-2172, 1098-5557 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Arid ecosystems cover ∼40% of the Earth’s terrestrial surface and store a high proportion of the global nitrogen (N) pool. They are low-productivity, low-biomass, and polyextreme ecosystems, i.e., with (hyper)arid and (hyper)oligotrophic conditions and high surface UV irradiation and evapotranspiration. These polyextreme conditions severely limit the presence of macrofauna and -flora and, particularly, the growth and productivity of plant species. , SUMMARY Arid ecosystems cover ∼40% of the Earth’s terrestrial surface and store a high proportion of the global nitrogen (N) pool. They are low-productivity, low-biomass, and polyextreme ecosystems, i.e., with (hyper)arid and (hyper)oligotrophic conditions and high surface UV irradiation and evapotranspiration. These polyextreme conditions severely limit the presence of macrofauna and -flora and, particularly, the growth and productivity of plant species. Therefore, it is generally recognized that much of the primary production (including N-input processes) and nutrient biogeochemical cycling (particularly N cycling) in these ecosystems are microbially mediated. Consequently, we present a comprehensive survey of the current state of knowledge of biotic and abiotic N-cycling processes of edaphic (i.e., open soil, biological soil crust, or plant-associated rhizosphere and rhizosheath) and hypo/endolithic refuge niches from drylands in general, including hot, cold, and polar desert ecosystems. We particularly focused on the microbially mediated biological nitrogen fixation, N mineralization, assimilatory and dissimilatory nitrate reduction, and nitrification N-input processes and the denitrification and anaerobic ammonium oxidation (anammox) N-loss processes. We note that the application of modern meta-omics and related methods has generated comprehensive data sets on the abundance, diversity, and ecology of the different N-cycling microbial guilds. However, it is worth mentioning that microbial N-cycling data from important deserts (e.g., Sahara) and quantitative rate data on N transformation processes from various desert niches are lacking or sparse. Filling this knowledge gap is particularly important, as climate change models often lack data on microbial activity and environmental microbial N-cycling communities can be key actors of climate change by producing or consuming nitrous oxide (N 2 O), a potent greenhouse gas. |
| Isotopic Characterization of Water Masses in the Southeast Pacific Region: Paleoceanographic Implications | Journal of Geophysical Research: Oceans | Reyes‐Macaya, D.; Hoogakker, B.; Martínez‐Méndez, G.; Llanillo, P.; Grasse, P.; Mohtadi, M.; Mix, A.; Leng, M.; Struck, U.; McCorkle, D.; Troncoso, M.; Gayo, E.; Lange, C.; Farías, L.; Carhuapoma, W.; Graco, M.; Cornejo‐D’Ottone, M.; De Pol Holz, R.; Fernandez, C.; Narvaez, D.; Vargas, C.; García‐Ar... | 2022 | Zonas Costeras | 10.1029/2021JC017525 | https://onlinelibrary.wiley.com/doi/10.1029/2021JC017525 | art: e2021JC017525 | Vol: 127 Issue: 1 | 2169-9275, 2169-9291 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | In this study, we used stable isotopes of oxygen (δ18O), deuterium (δD), and dissolved inorganic carbon (δ13CDIC) in combination with temperature, salinity, oxygen, and nutrient concentrations to characterize the coastal (71°–78°W) and an oceanic (82°–98°W) water masses (SAAW—Subantarctic Surface Water; STW—Subtropical Water; ESSW—Equatorial Subsurface water; AAIW—Antarctic Intermediate Water; PDW—Pacific Deep Water) of the Southeast Pacific (SEP). The results show that δ18O and δD can be used to differentiate between SAAW-STW, SAAW-ESSW, and ESSW-AAIW. δ13CDIC signatures can be used to differentiate between STW-ESSW (oceanic section), SAAW-ESSW, ESSW-AAIW, and AAIW-PDW. Compared with the oceanic section, our new coastal section highlights differences in both the chemistry and geometry of water masses above 1,000 m. Previous paleoceanographic studies using marine sediments from the SEP continental margin used the present-day hydrological oceanic transect to compare against, as the coastal section was not sufficiently characterized. We suggest that our new results of the coastal section should be used for past characterizations of the SEP water masses that are usually based on continental margin sediment samples. © 2021. The Authors. |
| Hydroclimate and ENSO Variability Recorded by Oxygen Isotopes From Tree Rings in the South American Altiplano | Geophysical Research Letters | Rodriguez‐Caton, M.; Andreu‐Hayles, L.; Daux, V.; Vuille, M.; Varuolo‐Clarke, A.; Oelkers, R.; Christie, D.; D’Arrigo, R.; Morales, M.; Palat Rao, M.; Srur, A.; Vimeux, F.; Villalba, R. | 2022 | Agua y Extremos | 10.1029/2021GL095883 | https://onlinelibrary.wiley.com/doi/10.1029/2021GL095883 | arte2021GL095883 | Vol: 49 Issue: 4 | 0094-8276, 1944-8007 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Hydroclimate variability in tropical South America is strongly regulated by the South American Summer Monsoon (SASM). However, past precipitation changes are poorly constrained due to limited observations and high-resolution paleoproxies. We found that summer precipitation and the El Niño-Southern Oscillation (ENSO) variability are well registered in tree-ring stable oxygen isotopes (δ18OTR) of Polylepis tarapacana in the Chilean and Bolivian Altiplano in the Central Andes (18–22°S, ∼4,500 m a.s.l.) with the northern forests having the strongest climate signal. More enriched δ18OTR values were found at the southern sites likely due to the increasing aridity toward the southwest of the Altiplano. The climate signal of P. tarapacana δ18OTR is the combined result of moisture transported from the Amazon Basin, modulated by the SASM, ENSO, and local evaporation, and emerges as a novel tree-ring climate proxy for the southern tropical Andes. © 2022. The Authors. |
| ¿Un eclipse solar en el medio de la noche? El evento total del 4 diciembre de 2021 en la Antártica | Boletín Antártico Chileno | Rojo, P.; Garreaud, R. | 2022 | https://www.inach.cl/wp-content/uploads/2022/09/Copia-de-BACh-41-1-vf.pdf | 20-27 | Vol: 41 Issue: 1 | |||||||
| Surface wave mitigation in a copper converter via H∞ mixed sensitivity control | IFAC-PapersOnLine 19th IFAC Symposium on Control, Optimization and Automation in Mining, Mineral and Metal Processing MMM 2022 Montreal, Canada, August 15-18, 2022 | Salas, F.; Torres, P.; Osses, A. | 2022 | 10.1016/j.ifacol.2022.09.260 | https://linkinghub.elsevier.com/retrieve/pii/S2405896322014951 | 156-161 | Vol: 55 Issue: 21 | 2405-8963 | Not indexed | All Open Access; Gold Open Access | English | In this paper, a robust control strategy for surface wave mitigation in copper converters is presented. In copper converters, the purification of copper is carried out by injection of air into the molten bath through lateral tuyeres. The constant rate of air injection produces undesirable oscillation and splashing of the bath in the surface diminishing the lifetime of the internal cover. An H∞mixed sensitivity approach is proposed to robustly control the air injection rate in order to eliminate the modes of oscillation in the surface even in the case when uncertainty in the parameters of the model and noise in the measurements are present. The effectiveness of the proposed approach is shown by simulations and by comparison with a non-robust LQG control strategy. © 2022 Elsevier B.V.. All rights reserved. | |
| Soil research, management, and policy priorities in Chile | Geoderma Regional | Salazar, O.; Casanova, M.; Fuentes, J.; Galleguillos, M.; Nájera, F.; Perez-Quezada, J.; Pfeiffer, M.; Renwick, L.; Seguel, O.; Tapia, Y. | 2022 | Cambio de Uso de Suelo | 10.1016/j.geodrs.2022.e00502 | https://linkinghub.elsevier.com/retrieve/pii/S2352009422000220 | e00502 | Vol: 29 | 2352-0094 | Thomson Reuters ISI (SCIE) | English | ||
| Global phylogenomic novelty of the Cas1 gene from hot spring microbial communities | Frontiers in Microbiology | Salgado, O.; Guajardo-Leiva, S.; Moya-Beltrán, A.; Barbosa, C.; Ridley, C.; Tamayo-Leiva, J.; Quatrini, R.; Mojica, F.; Díez, B. | 2022 | Zonas Costeras | 10.3389/fmicb.2022.1069452 | https://doi.org/10.3389/fmicb.2022.1069452 | art: 1069452 | Vol: 13 | 1664-302X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Cas1 protein is essential for the functioning of CRISPR-Cas adaptive systems. However, despite the high prevalence of CRISPR-Cas systems in thermophilic microorganisms, few studies have investigated the occurrence and diversity of Cas1 across hot spring microbial communities. Phylogenomic analysis of 2,150 Cas1 sequences recovered from 48 metagenomes representing hot springs (42–80°C, pH 6–9) from three continents, revealed similar ecological diversity of Cas1 and 16S rRNA associated with geographic location. Furthermore, phylogenetic analysis of the Cas1 sequences exposed a broad taxonomic distribution in thermophilic bacteria, with new clades of Cas1 homologs branching at the root of the tree or at the root of known clades harboring reference Cas1 types. Additionally, a new family of casposases was identified from hot springs, which further completes the evolutionary landscape of the Cas1 superfamily. This ecological study contributes new Cas1 sequences from known and novel locations worldwide, mainly focusing on under-sampled hot spring microbial mat taxa. Results herein show that circumneutral hot springs are environments harboring high diversity and novelty related to adaptive immunity systems. Copyright © 2022 Salgado, Guajardo-Leiva, Moya-Beltrán, Barbosa, Ridley, Tamayo-Leiva, Quatrini, Mojica and Díez. |
| Are Citizens Ready for Active Climate Engagement or Stuck in a Game of Blame? Local Perceptions of Climate Action and Citizen Participation in Chilean Patagonia | Sustainability | Sapiains, R.; Azócar, G.; Moraga, P.; Valenzuela, C.; Aldunce, P.; Cornejo, C.; Rojas, M.; Pulgar, A.; Medina, L.; Bozkurt, D. | 2022 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | 10.3390/su141912034 | https://www.mdpi.com/2071-1050/14/19/12034 | 12034 | Vol: 14 Issue: 19 | 2071-1050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Deep structural transformations aimed at strengthening climate action and community participation are occurring in Chile, especially after the social unrest of October 2019. The ongoing political crisis has even generated the unprecedented possibility of writing a new constitution through an entirely democratic process. This article explores to what extent these structural transformations are also associated with cognitive and relational changes in the population, especially in terms of community participation. An online survey (n = 1.117) was applied to people over 18 years old in Punta Arenas in November 2020. This is the southernmost city of the American continent, one of the areas most affected by climate change, highly isolated from the rest of the country, and with a strong regional ecological identity. Results show that climate change is perceived as the main environmental problem affecting the city, with multiple negative consequences, but also with some potentially positive impacts. At the same time, environmental and constitutional expectations suggest the state of the environment is deemed to be critical for the future of the city. However, a traditional top-down understanding of community participation still prevails as most participants perceive the citizens’ role in dealing with environmental issues as limited to individual, passive, and reactive actions, or reduced to being responsible consumers. These results show that transforming institutions, rules and regulations alone does not guarantee a broader engagement of local communities in more ambitious, committed, and lasting climate action, even with a high climate change concern in the population. Creating strategies aimed at more profound cognitive and relational changes from a bottom-up perspective will also be necessary to avoid negative transformation trajectories. |
| La libre appréciation de la preuve et le litige climatique au Chili | Revue juridique de l’environnement | Sariego, P. | 2022 | https://www.cairn.info/revue-juridique-de-l-environnement-2022-3-page-503.htm | 503-514 | Vol: 47 Issue: 3 | 0397-0299 | French | Les Tribunaux de l’environnement chiliens sont régis par les règles de la libre appréciation de la preuve selon lesquelles ils l’apprécient librement. Dans ce cadre, les juges spécialisés doivent exprimer les raisons juridiques, logiques, scientifiques, techniques ou issues de leur expérience, en vertu desquelles ils lui attribuent une valeur ou la rejettent. Ces règles, à la lumière du principe de précaution et de la formation technique des juges, ont favorisé par exemple la prise en considération des changements climatiques dans la détermination des impacts d’une activité productive (minière) sur les eaux souterraines d’une zone désertique au Chili. | ||||
| Socioeconomic inequalities and the surface heat island distribution in Santiago, Chile | Science of The Total Environment | Sarricolea, P.; Smith, P.; Romero-Aravena, H.; Serrano-Notivoli, R.; Fuentealba, M.; Meseguer-Ruiz, O. | 2022 | Ciudades Resilientes | 10.1016/j.scitotenv.2022.155152 | https://linkinghub.elsevier.com/retrieve/pii/S0048969722022458 | 155152 | Vol: 832 | 00489697 | Thomson Reuters ISI (SCIE) | English | Surface urban heat islands (SUHIs) are an important socio-environmental problem associated with large cities, such as the Santiago Metropolitan Area (SMA), in Chile. Here, we analyze daytime and nighttime variations of SUHIs for each season of the year during the period 2000–2020. To evaluate socioeconomic inequities in the distribution of SUHIs, we establish statistical relationships with socioeconomic status, land price, and urban vegetation. We use the MODIS satellite images to obtain the land surface temperatures and the normalized difference vegetation index (NDVI) through the Google Earth Engine platform. The results indicate more intense SUHIs during the nighttime in the eastern sector, coinciding with higher socioeconomic status and larger green areas. This area during the day is cooler than the rest of the city. The areas with lower and middle socioeconomic status suffer more intense SUHIs (daytime and nighttime) and match poor environmental and urban qualities. These results show the high segregation of SMA. Urban planning is subordinated to land prices with a structure maintained over the study period. The lack of social-climate justice is unsustainable, and such inequalities may be exacerbated in the context of climate change. Thus, these results can contribute to the planning of the SMA. © 2022 Elsevier B.V. | |
| Acta de resúmenes | Conferencia Internacional 2021 Ciudades Resilientes desde el Sur Global | Sarricolea, P.; Urquiza, A.; Gallardo, L.; Gayo, E.; Lambert, F.; Boisier, J.; Garreaud, R.; Huneeus, N.; Osses, M.; Ibarra, C. | 2022 | https://www.cr2.cl/acta-de-resumenes-conferencia-internacional-2021-ciudades-resilientes-desde-el-sur-global/ | 246 | cr2.cl | La Conferencia Internacional 2021 Ciudades Resilientes desde el Sur Global, nace de una alianza entre el Centro de Desarrollo Urbano Sustentable CEDEUS, el Centro de Investigación para la Gestión Integrada del Riesgo de Desastres, CIGIDEN y el Centro de Ciencia del Clima y la Resiliencia (CR)2. Todas instituciones de investigación de excelencia FONDAP, financiados por la Agencia Nacional de Investigación y Desarrollo, ANID, e integradas por las mejores universidades chilenas. Anclada en la ciencia con impacto para la política pública, la Conferencia Internacional Ciudades Resilientes, abordó durante tres días el rol preponderante de las ciudades en los problemas globales, como las desigualdades sociales, las inequidades urbanas y territoriales, sumado a los impactos ambientales, las amenazas naturales, el cambio climático y las pandemias, entre otras. Pero, al mismo tiempo, estas ciudades ofrecen un espacio invaluable para crear e implementar soluciones innovadoras, para investigar y desarrollar ciencia con y para los territorios. | |||||||
| Photochemical sensitivity to emissions and local meteorology in Bogotá, Santiago, and São Paulo | Elementa: Science of the Anthropocene | Seguel, R.; Gallardo, L.; Osses, M.; Rojas, N.; Nogueira, T.; Menares, C.; de Fatima Andrade, M.; Belalcázar, L.; Carrasco, P.; Eskes, H.; Fleming, Z.; Huneeus, N.; Ibarra-Espinosa, S.; Landulfo, E.; Leiva, M.; Mangones, S.; Morais, F.; Moreira, G.; Pantoja, N.; Parraguez, S.; Rojas, J.; Rondanelli,... | 2022 | Ciudades Resilientes; Zonas Costeras | 10.1525/elementa.2021.00044 | https://online.ucpress.edu/elementa/article/10/1/00044/169476/Photochemical-sensitivity-to-emissions-and-local | 00044 | Vol: 10 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | This study delves into the photochemical atmospheric changes reported globally during the pandemic by analyzing the change in emissions from mobile sources and the contribution of local meteorology to ozone (O3) and particle formation in Bogotá (Colombia), Santiago (Chile), and São Paulo (Brazil). The impact of mobility reductions (50%–80%) produced by the early coronavirus-imposed lockdown was assessed through high-resolution vehicular emission inventories, surface measurements, aerosol optical depth and size, and satellite observations of tropospheric nitrogen dioxide (NO2) columns. A generalized additive model (GAM) technique was also used to separate the local meteorology and urban patterns from other drivers relevant for O3 and NO2 formation. Volatile organic compounds, nitrogen oxides (NOx), and fine particulate matter (PM2.5) decreased significantly due to motorized trip reductions. In situ nitrogen oxide median surface mixing ratios declined by 70%, 67%, and 67% in Bogotá, Santiago, and São Paulo, respectively. NO2 column medians from satellite observations decreased by 40%, 35%, and 47%, respectively, which was consistent with the changes in mobility and surface mixing ratio reductions of 34%, 25%, and 34%. However, the ambient NO2 to NOx ratio increased, denoting a shift of the O3 formation regime that led to a 51%, 36%, and 30% increase in the median O3 surface mixing ratios in the 3 respective cities. O3 showed high sensitivity to slight temperature changes during the pandemic lockdown period analyzed. However, the GAM results indicate that O3 increases were mainly caused by emission changes. The lockdown led to an increase in the median of the maximum daily 8-h average O3 of between 56% and 90% in these cities. |
| The last millennium viewed from a fine-resolution freshwater diatom record from northwestern Patagonia | Quaternary Science Reviews | Sepúlveda-Zúñiga, E.; Maidana, N.; Villacís, L.; Sagredo, E.; Moreno, P. | 2022 | Agua y Extremos | 10.1016/j.quascirev.2022.107806 | https://linkinghub.elsevier.com/retrieve/pii/S0277379122004371 | 107806 | Vol: 296 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | Little is known about the response of terrestrial and aquatic ecosystems to changes in climatic and human influences during the last millennium in northwestern Patagonia (NWP, 40°-44°S). By virtue of their sensitivity and specificity, diatoms are ideal for examining past changes in aquatic ecosystems and deciphering the ranges of variability under natural and human-induced conditions. To date, however, very few fossils diatom studies have examined in detail the environmental evolution during the last millennium throughout Patagonia. Here we present a fine-resolution diatom record from a lake-sediment core collected from Lago Pichilaguna (41°S), a closed-basin and shallow lake with a small catchment area located in the lowlands of the Chilean Lake District in NWP. The record spans the last millennium with a median time resolution of ∼12 years between samples, and shows abundant small Aulacoseira spp. between ∼1000-900 and ∼600-300 cal yr BP, which alternate in dominance with small fragilarioids and small raphid diatoms between ∼900-600 and ∼300-200 cal yr BP. A rapid shift to planktonic diatoms started at ∼200 cal yr BP and led to their modern dominance. We interpret centennial-scale changes in temperature, precipitation, and lake turbulence, with warm/dry/stratified phases between ∼1000-900 and ∼600-300 cal yr BP related to weak westerly winds, and intervals of cold/wet and mixed water column conditions between ∼900-600 and ∼300-200 cal yr BP, favored by stronger winds. The transition from periphytic to planktonic diatoms that started at ∼200 cal yr BP suggests juxtaposition of the warmest/driest phase of the last millennium and the onset of large-scale disturbance by Chilean/European settlers in NWP. Our results reveal that human disturbance during historical time surpassed the natural ranges of variability and resilience of aquatic and terrestrial ecosystems over the last millennium, generating abrupt changes in biodiversity, species composition, and community structure. © 2022 Elsevier Ltd | |
| Long-term airborne particle pollution assessment in the city of Coyhaique, Patagonia, Chile | Urban Climate | Solís, R.; Toro A., R.; Gomez, L.; Vélez-Pereira, A.; López, M.; Fleming, Z.; Fierro, N.; Leiva G., M. | 2022 | Ciudades Resilientes | 10.1016/j.uclim.2022.101144 | https://linkinghub.elsevier.com/retrieve/pii/S2212095522000621 | 101144 | Vol: 43 | 2212-0955 | Thomson Reuters ISI (SCIE) | English | An air pollution assessment in a small city located in the heart of Chilean Patagonia is presented. Seven years (2014–2020) of PM concentration levels retrieved from two monitoring stations permits an evaluation of the city's pollution variability, the effect of meteorological variables and long-term trends of air pollution. The highest PM concentration levels observed during the coldest months are mainly related to an increasing emission associated with the intensive use of firewood for residential heating and cooking. The most polluted days are associated with low temperatures, low wind speed and high PM2.5/PM10 ratios, which is consistent with the predominance of local firewood sources over background emissions. A decrease in both PM fractions over time has been estimated (PM10: -4.1, CI99%: −5.7 to −2.9 and PM2.5: -2.2, CI99%: −3.5 to −1.3 μg m−3 year−1). However, the annual average PM mass concentrations in Coyhaique exceeded both national and international air quality thresholds. The city reported a percent of annual exceedances of the daily WHO guidelines of 57% for PM10 and 77% for PM2.5. These numbers highlight the serious air pollution problem of the city of Coyhaique, which exhibits air pollution levels comparable to those of many polluted megacities in the world. © 2022 Elsevier B.V. | |
| Glacier fluctuations in the northern Patagonian Andes (44°S) imply wind-modulated interhemispheric in-phase climate shifts during Termination 1 | Scientific Reports | Soteres, R.; Sagredo, E.; Kaplan, M.; Martini, M.; Moreno, P.; Reynhout, S.; Schwartz, R.; Schaefer, J. | 2022 | Agua y Extremos | 10.1038/s41598-022-14921-4 | https://www.nature.com/articles/s41598-022-14921-4 | 10842 | Vol: 12 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract The Last Glacial Termination (T1) featured major changes in global circulation systems that led to a shift from glacial to interglacial climate. While polar ice cores attest to an antiphased thermal pattern at millennial timescales, recent well-dated moraine records from both hemispheres suggest in-phase fluctuations in glaciers through T1, which is inconsistent with the bipolar see-saw paradigm. Here, we present a glacier chronology based on 30 new 10 Be surface exposure ages from well-preserved moraines in the Lago Palena/General Vintter basin in northern Patagonia (~ 44°S). We find that the main glacier lobe underwent profound retreat after 19.7 ± 0.7 ka. This recessional trend led to the individualization of the Cerro Riñón glacier by ~ 16.3 ka, which underwent minor readvances at 15.9 ± 0.5 ka during Heinrich Stadial 1, during the Antarctic Cold Reversal with successive maxima at 13.5 ± 0.4, 13.1 ± 0.4, and 13.1 ± 0.5 ka, and a minor culmination at 12.5 ± 0.4 ka during Younger Dryas time. We conclude that fluctuations of Patagonian glaciers during T1 were controlled primarily by climate anomalies brought by shifts in the Southern Westerly Winds (SWW) locus. We posit that the global covariation of mountain glaciers during T1 was linked to variations in atmospheric CO 2 (atmCO 2 ) promoted by the interplay of the SWW-Southern Ocean system at millennial timescales. |
| Glacial geomorphology of the central and southern Chilotan Archipelago (42.2°S–43.5°S), northwestern Patagonia | Journal of Maps | Soteres, R.; Sagredo, E.; Moreno, P.; Lowell, T.; Alloway, B. | 2022 | Agua y Extremos | 10.1080/17445647.2021.2008538 | https://www.tandfonline.com/doi/full/10.1080/17445647.2021.2008538 | 1-17 | Vol: 18 | 1744-5647 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | We present a geomorphic map of the glacial landforms associated with the Golfo Corcovado ice lobe in northwestern Patagonia. Built upon prior studies, our map elaborates on the central and southern sectors of Isla Grande de Chiloé and neighboring islands. Through a combination of remote sensing techniques and exhaustive fieldwork, we identified a suite of ice-marginal, subglacial, and glaciofluvial features created by the Golfo Corcovado ice lobe during four maxima within the last glacial cycle, in none of which the ice-front reached the Pacific coast of Isla Grande de Chiloé. Our mapping builds a foundation and provides insights for future interdisciplinary research on the Late Quaternary sequence of glacial and paleoclimatic events in this key sector of northwestern Patagonia. © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. |
| Land cover in the Purapel fluvial catchment | Sotomayor, Benjamín; Tolorza, Violeta; Poblete-Caballero, Dagoberto; Leal, Claudia; Galleguillos, Mauricio | 2022 | 10.5281/ZENODO.6974312 | https://zenodo.org/record/6974312 | Zenodo | The dataset contains 6 Land Cover maps at a 30m/pixel spatial resolution for the Purapel river catchment located in South-Central Chile. They were generated for the summer periods of 1986, 2000, 2005, 2010, 2015 and 2017. Maps of 1986-2015 were generated using atmospherically corrected Landsat CDR Scenes (images courtesy of the U.S. Geological Survey) including VNIR and SWIR bands from the TM5, ETM+ and OLI sensors and vegetation indices as auxiliary bands to highlight phenological differences among covers. Specifically the Normalized Difference Vegetation Index (NDVI) (Rouse et al,. 1974), the Green NDVI (Gitelson et al., 1996) and NDVI winter-summer Difference Index (ΔNDVI). Training and validation points were defined from field trips to the area in 2014-2015, various mid resolution satellite imagery sources and high-resolution Google Earth imagery (Map data ©2015 Google) when available. A topographic correction was applied using the C-Correction method (Teillet et al 1982), as proposed by Hantson and Chuvieco (2011), and the SRTM v3 DEM to account for the effect of local relief in the scene’s lighting. Accuracy assessment resulted in Overall Accuracy (OA), ranging from 82% to 92% (table 1). Table 1. Overall Accuracies for Land Cover maps from 1986 to 2017 Year OA 1986 89.7 2000 92.2 2005 91.5 2010 89.8 2015 82.7 2017 0.98 The 2017 map was generated using Random Forest classifier using several SI from Sentinel 2, Sentinel 1 C-band radar data (imagery from European Space Agency courtesy of the U.S. Geological Survey) and hydro-geomorphic indices obtained from 2009 LiDAR DTM data (Tolorza et al., 2022). Ninety polygons were used for training and thirty polygons and the classification of Zhao et al. (2016) were used for validation, obtaining an overall accuracy 0.98 (table 1). The 7 land cover classes defined following these codes and land use / covers: 0 = Unclassified 1 = Others (mainly crops and natural prairies in riverbeds) 2 = Native Forest (mainly secondary-growth deciduous Nothofagus sp. Stands) 3 = Shrubland (highly degraded formation of xerophytic and sclerophyllous shrubs such as Acacia caven, Quillaja saponaria and Lithraea caustica, among others). 4 =Tree Plantations (industrial monocultures of Pinus radiata and Eucalyptus spp. of various age and development) 5 = Seasonal grassland (annual pastures which wither in summer and urban areas) 6 = Clear cuts (bare lands within industrial forestry surface) Codes 7 to 9 are specific to 2015 y 2017 because of the occurrence of two large (>5,000 hectares) fire events, and represent different Fire Severity levels based on the dNBR index (López and Caselles, 1991) according to Key and Benson (2006). They represent the following cases: 7= Low Severity fire 8 = Moderate severity fire 9 = High severity fire Sources: Hantson, S. Chuvieco, E. 2011. Evaluation of different topographic correction methods for Landsat imagery. International Journal of Applied Earth Observation and Geoinformation 13:691-700. Rouse, J., R. Haas, J. Schell, and D. Deering. 1974. Monitoring vegetation systems in the Great Plains with erts. Third Earth Resources Technology Satellite-1 Symposium Volume I: Technical Presentations. NASA SP-351, compiled and edited by S.C. Freden, E.P. Mercanti, and M.A. Becker. Washington, DC: National Aeronautics and Space Administration Gitelson, A., Y. Kaufman, and M. Merzlyak. 1996. Use of a green channel in remote sensing of global vegetation from EOS-MODIS. Remote Sensing of Environment 58(3):289-298. Teillet, P., B. Guindon, and D. Goodenough. 1982. On the slope-aspect correction of multispectral scanner data. Canadian Journal of Remote Sensing 8:84–106. Key, C. Benson, N. 2006. Landscape Assessment: Ground measure of severity, the Composite Burn Index; and Remote sensing of severity, the Normalized Burn Ratio. FIREMON: Fire Effects Monitoring and Inventory System. Pp: 1-51. López, MJ. Caselles, V. 1991. Mapping burns and natural reforestation using Thematic Mapper data. Geocarto International (1) 1991: 31- 37. Tolorza, V. Poblete-Caballero, D. Banda, D. Little, C. Galleguillos, M. 2022. An operational method for mapping the composition of post-fire litter. Remote Sensing letters (13) 2022: 511-521. 10.1080/2150704X.2022.2040752 Zhao, Y. D. Feng, L. Yu, X. Wang, Y. Chen, Y. Bai, H. Hernández, et al. 2016. Detailed Dynamic Land Cover Mapping of Chile: Accuracy Improvement by Integrating Multi-temporal Data. Remote Sensing of Environment 183: 170–185. 10.1016/j.rse.2016.05.016. | |||||||
| Out of steam? A social science and humanities research agenda for geothermal energy | Energy Research & Social Science | Spijkerboer, R.; Turhan, E.; Roos, A.; Billi, M.; Vargas-Payera, S.; Opazo, J.; Armiero, M. | 2022 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.erss.2022.102801 | https://linkinghub.elsevier.com/retrieve/pii/S2214629622003048 | 102801 | Vol: 92 | 2214-6296 | Thomson Reuters ISI (SSCI) | All Open Access; Hybrid Gold Open Access | English | The potential of geothermal energy for energy transition is increasingly recognized by governments around the world. Whether geothermal energy is a sustainable source of heat and/or electricity depends on how it is deployed in specific contexts. Therefore, it is striking that there is only limited attention to geothermal energy from a social science and humanities (SSH) perspective. Geothermal energy is largely conceptualized as a technological and/or geological issue in both science and practice. This perspective article aims to go beyond such conceptualizations by positioning social science research as an important lens to explore the promises and pitfalls of geothermal energy. We first provide an overview of the current state of geothermal energy as a decarbonization strategy. Second, we move on to review the existing literature. This review shows that studies that do address geothermal energy from an SSH perspective tend to be of a descriptive nature and lack analytical diversity. Third, we discuss three complementary theoretical approaches that are used in the social sciences to observe and address other forms of energy and energy transition. We believe that socio-technical assemblages, systems, and imaginaries can provide fruitful analytical lenses to study the promises, pitfalls and spatialization of geothermal energy. We conclude the paper with a research agenda and call for further engagement with this topic in SSH research, with attention to specificities of global South and North contexts. © 2022 The Authors |
| Short-Interval, Severe Wildfires Alter Saproxylic Beetle Diversity in Andean Araucaria Forests in Northwest Chilean Patagonia | Forests | Tello, F.; González, M.; Micó, E.; Valdivia, N.; Torres, F.; Lara, A.; García-López, A. | 2022 | Cambio de Uso de Suelo | 10.3390/f13030441 | https://www.mdpi.com/1999-4907/13/3/441 | 441 | Vol: 13 Issue: 3 | 1999-4907 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The occurrence of short-interval, severe wildfires are increasing drastically at a global scale, and appear as a novel phenomenon in areas where fire historically returns in large time lapses. In forest ecosystems, these events induce drastic changes in population dynamics, which could dramatically impact species diversity. Here, we studied the effect on diversity of recent short-interval, severe wildfires (SISF), which occurred in rapid succession in the summers of 2002 and 2015 in Chilean Northern Patagonian Araucaria–Nothofagus forests. We analyzed the diversity of deadwood-dependent (i.e., saproxylic) and fire-sensitive beetles as biological indicators across four conditions: 2002-burned areas, 2015-burned areas, SISF areas (i.e., burned in 2002 and again in 2015), and unburned areas. Saproxylic beetles were collected using window traps in 2017 to 2019 summer seasons. To investigate the mechanisms underpinning the fire-related disturbance of the assemblage, we evaluated the effects of post-fire habitat quality (e.g., dead wood decomposition) and quantity (e.g., burned dead wood volume and tree density) on the abundances and species richness of the entire assemblage and also multiple trophic groups. Compared with the unburned condition, SISF drastically reduced species richness, evenness, and Shannon’s diversity and altered the composition of the saproxylic beetle assemblages. The between-condition variation in composition was accounted for by a species replacement (turnover) between SISF and 2015-burned areas, but both species replacement and extinction (nestedness) between SISF and unburned areas. Dead wood decomposition and tree density were the variables with the strongest effects on the abundance and species richness of the entire saproxylic beetle assemblage and most trophic groups. These results suggest that SISF, through degraded habitat quality (dead wood decomposition) and quantity (arboreal density), have detrimental impacts on diversity and population dynamics of saproxylic beetle assemblages. Therefore, habitat loss is a central mechanism underpinning fire-related biodiversity loss in these forest ecosystems. |
| An operational method for mapping the composition of post-fire litter | Remote Sensing Letters | Tolorza, V.; Poblete-Caballero, D.; Banda, D.; Little, C.; Leal, C.; Galleguillos, M. | 2022 | Cambio de Uso de Suelo | 10.1080/2150704X.2022.2040752 | https://www.tandfonline.com/doi/full/10.1080/2150704X.2022.2040752 | 511-521 | Vol: 13 Issue: 5 | 2150-704X | Thomson Reuters ISI (SCIE) | English | Recent increase in the frequency and spatial extent of wildfires motivates the quick recognition of the affected soil properties over large areas. Digital Soil Mapping is a valuable approach to map soil attributes based on remote sensing and field observations. We predicted the spatial distribution of post-fire litter composition in a 40,600 ha basin burned on the 2017 wildfire of Chile. Remotely sensed data of topography, vegetation structure and spectral indices (SI) were used as predictors of random forest (RF) models. Litter sampled in 60 hillslopes after the fire provided training and validation data. Predictors selected by the Variable Selection Using Random Forests (VSURF) algorithm resulted in models for litter composition with acceptable accuracy (coefficient of determination, R 2 = 0.51–0.64, Normalized Root Mean Square Error, NRMSE = 16.9–22.1, percentage bias, pbias = −0.35%-0.5%). Modelled litter parameters decrease in concentration respect to the degree of burn severity, and the pre-fire biomass. Because pre-fire vegetation was conditioned by land cover and by a previous (2 years old) wildfire event, our results highlight the cumulative effect of severe wildfires in the depletion of litter composition. © 2022 Informa UK Limited, trading as Taylor & Francis Group. | |
| A pilot study for climate risk assessment in agriculture: a climate-based index for cherry trees | Natural Hazards | Tudela, V.; Sarricolea, P.; Serrano-Notivoli, R.; Meseguer-Ruiz, O. | 2022 | Ciudades Resilientes | 10.1007/s11069-022-05549-8 | https://link.springer.com/10.1007/s11069-022-05549-8 | 163-185 | Vol: 115 | 0921-030X, 1573-0840 | Thomson Reuters ISI (SCIE) | English | Cherry trees are one of Chile’s most important specialty crop activities. Its commercial orchards have an extensive spatial distribution between the 31° S and 48° S, spreading from semiarid to tundra climates, but the trees appear primarily in the Mediterranean climate. Different extreme weather events, such as frosts, precipitation, and high temperatures, affect this crop at different phenological stages, especially in bloom, ripening, and floral differentiation. Based on a high-resolution climatic-gridded dataset of daily temperature and precipitation data, we defined an integrated risk index (RI) representing the frequency of occurrence of the events throughout the plant development period and considering each type of risk affecting each concrete phenological stage. High RI values indicate high climatic risk. The RI follows a meridional pattern influenced by elevation, with higher values in the highest elevations between 36° S and 40° S, sensitive to the simultaneous occurrence of frosts and precipitation events. The northern coast exhibited the lowest risk values, while a general gradient from low values in coastal areas to higher ones in inland elevated zones revealed an altitudinal pattern. Low-risk areas have a sparse distribution of crops, which can be explained by several factors restricting cherry cultivation such as soil limitations, high slopes, lack of productive support infrastructure, and competition with other profitable forestry and agricultural activities in the north and forest production in the south. These results will help to improve climate impact assessments for production systems, which can be conducted by following an easy-to-understand tool. © 2022, The Author(s), under exclusive licence to Springer Nature B.V. | |
| Revisión de indicaciones a las normas sobre crisis climática; medio ambiente, biodiversidad, principios de la bioética y bienes naturales comunes; y derechos de la naturaleza en la propuesta de nueva Constitución | Ubilla, K. | 2022 | https://www.cr2.cl/revision-de-indicaciones-a-las-normas-sobre-crisis-climatica-medio-ambiente-biodiversidad-principios-de-la-bioetica-y-bienes-naturales-comunes-y-derechos-de-la-naturaleza-en-la-propuesta-de-nueva/ | 11 | cr2.cl | Spanish | En el marco del trabajo de investigadoras e investigadores del (CR)2 de la línea Gobernanza e Interfaz Ciencia-Política en apoyo a las propuestas de contenidos para las normas elaboradas por las y los convencionales constituyentes en temas de cambio climático, crisis climática y relacionados, se presenta una revisión de las indicaciones discutidas y aprobadas por la comisión de medio ambiente, derechos de la naturaleza, bienes naturales comunes y modelo económico de la Convención Constitucional en la sesión Nº47 del 22 de febrero del 2022. En dicha jornada se realizó la votación del bloque A de indicaciones, relativo a las temáticas: 1) Crisis climática, 2) Medio ambiente, biodiversidad, principios de la bioética y bienes naturales comunes; o Ekuwuwun/Itxofill mogen; Suma Qamaña, Sumak Kawsay, Ckayahia Ckausama, buen vivir, como principio orientador en materia de derechos de la naturaleza o derecho a la montaña y senderos ancestrales o política plurinacional de residuos, 3) Derechos de la naturaleza. |
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| Revisión de indicaciones a las normas sobre Derechos de la Vida no Humana, delitos ambientales y democracia ambiental en la propuesta de nueva Constitución | Ubilla, K. | 2022 | https://www.cr2.cl/normas-sobre-derechos-de-la-vida-no-humana-delitos-ambientales-y-democracia-ambiental-en-la-propuesta-de-nueva-constitucion/ | 14 | cr2.cl | En el marco del trabajo de investigadoras e investigadores del (CR)2 de la línea Gobernanza e Interfaz Ciencia-Política en apoyo a las propuestas de contenidos para las normas elaboradas por las y los convencionales constituyentes en temas de cambio climático, crisis climática y relacionados, se presenta una revisión de las indicaciones discutidas y aprobadas por la comisión de medio ambiente, derechos de la naturaleza, bienes naturales comunes y modelo económico de la Convención Constitucional en la sesión Nº48 del 23 de febrero del 2022. En dicha jornada se realizó la votación del bloque A de indicaciones, relativo a las temáticas: 4) Derechos de la vida no humana, 5) Deber de protección, justicia intergeneracional, delitos ambientales y principios de no regresión ambiental, preventivo, precautorio y otros; o Principio Correctivo, Reparativo y Pedagógico o Reparación de “zonas de sacrificio”, restauración ecológica 6) Democracia ambiental, derechos de acceso a la participación, información y justicia ambiental. |
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| Informe a las naciones: "Marea roja" y cambio global: Elementos para la construcción de una gobernanza integrada de las Floraciones de Algas Nocivas (FAN) | Ugarte, A.; Romero, J.; Farías, L.; Sapiains, R.; Aparicio, P.; Ramajo, L.; Aguirre, C.; Masotti, I.; Jacques, M.; Aldunce,, P.; Alonso, C.; Azócar, G.; Bada, R.; Barrera, F.; Billi, M.; Boisier, J.; Carbonell, P.; de la Maza, L.; de la Torre, M.; Espinoza-González, O.; Faúndez, J.; Garreaud, R.; Gu... | 2022 | https://www.cr2.cl/fan/ | 88 | Spanish | ||||||||
| Resilience and organization: Innovation as a challenge for universities; [Resiliencia y organización: La innovación como desafío de las universidades] | Revista Mad | Urquiza, A.; Labraña, J.; Rahmer, B.; Puyol, F.; Allendes, Á.; Gómez, y. | 2022 | Ciudades Resilientes | 10.5354/0719-0527.2023.70849 | https://revistamad.uchile.cl/index.php/RMAD/article/view/70849/74162 | 1-10 | Vol: - Issue: 47 | 07180527 | Thomson Reuters ISI (ESCI) | Spanish | Innovation has become a central dimension of contemporary universities. However, there are still no guidelines on how to encourage universities to advance organizationally in this direction. Using elements of social systems theory, this article addresses the challenges faced by contemporary universities in relation to the relevance of innovation, suggesting guidelines for their reform. The organization of the resilient university, centered on the implementation of the principles of reflection, participation, and anticipation, allows progress in this direction. The article ends with a summary and a general reflection on the resilient university. © 2022 Universidad de Chile. All rights reserved. | |
| An extraordinary dry season precipitation event in the subtropical Andes: Drivers, impacts and predictability | Weather and Climate Extremes | Valenzuela, R.; Garreaud, R.; Vergara, I.; Campos, D.; Viale, M.; Rondanelli, R. | 2022 | Agua y Extremos; Zonas Costeras | 10.1016/j.wace.2022.100472 | https://linkinghub.elsevier.com/retrieve/pii/S2212094722000548 | 100472 | Vol: 37 | 2212-0947 | Thomson Reuters ISI (SCIE) | English | A major storm impacted the subtropical Andes during 28–31 January 2021 producing 4-days accumulated precipitation up to 100 mm over central-south Chile. These are high accumulations even for winter events but the storm occurred in the middle of the summer when precipitation is virtually absent, conferring it an extraordinary character. Similar storms have occurred only 2–3 times in the past century. The January 2021 event included periods of high rainfall intensity, hail and lighting, causing dozens of landslides and flash floods with the concomitant social impacts and economical losses. Here we examine the meteorological drivers of this storm at multiples scales, its climatological context, the associated surface impacts, and some aspects of its predictability. About a week before the storm development over central Chile, a large-scale perturbation in the central South Pacific set the stage for the formation of a zonal jet aloft and zonal atmospheric river (ZAR) that extended eastward until reaching the west coast of South America. The ZAR landfalled at 39°S and its subsequent northward displacement resulted in copious orographic precipitation over the Andes and adjacent lowlands, concomitant with a relatively warm environment during the first phase of the storm (28–29 January). During the second phase (30–31 January) the ZAR decayed rapidly but left behind significant amount of water vapor and the formation of a cut-off low (COL) in its poleward flank. The COL facilitated both advection of cyclonic vorticity and cold air at mid-levels, setting the environment for deep convection, intense rain showers, significant lightning activity, and hail. An assessment of the quantitative precipitation forecast (QPF) from the operational Global Forecast System (GFS) indicates that the model captured well the 96-h precipitation accumulation (28–31 January) in terms of timing and spatial extent. However, specific zones with the largest accumulations varied as a function of lead time. The more stable precipitation during the ZAR phase was better predicted than the convective precipitation during the COL phase. Proper dissemination of these forecast and recently established infrastructure contributed to ease the impact of this extraordinary event on the general population. © 2022 The Authors | |
| Sclerophyllous Forest Tree Growth Under the Influence of a Historic Megadrought in the Mediterranean Ecoregion of Chile | Ecosystems | Venegas-González, A.; Muñoz, A.; Carpintero-Gibson, S.; González-Reyes, A.; Schneider, I.; Gipolou-Zuñiga, T.; Aguilera-Betti, I.; Roig, F. | 2022 | Agua y Extremos | 10.1007/s10021-022-00760-x | https://link.springer.com/10.1007/s10021-022-00760-x | 344-361 | Vol: 26 | 1432-9840, 1435-0629 | Thomson Reuters ISI (SCIE) | English | The Mediterranean-type Ecosystems of Central Chile is one of the most threatened regions in South America by global change, particularly evidenced by the historical megadrought that has occurred in central Chile since 2010. The sclerophyllous forest stands out, whose history and relationship with drought conditions has been little studied. Cryptocarya alba and Beilschmiedia miersii (Lauraceae), two large endemic trees, represent an opportunity to analyze the incidence of intense droughts in the growth of sclerophyllous forests by analyzing their tree rings. Here, we considered > 400 trees from nineteen populations of C. alba and B. miersii growing across a latitudinal gradient (32°–35° S). To study the influence of local and large-scale climatic variability on tree growth, we first grouped the sites by species and explored the relationships between tree-growth patterns of C. alba and B. miersii with temperature, precipitation, and climate water deficit (CWD). Second, we performed Principal Component Analysis to detect common modes of variability and to explore relationships between growth patterns and their relationship to Palmer Drought Severity Index (PDSI), ENSO and SAM indices. We detected a breaking point as of 2002 at regional level, where a persistent and pronounced decrease in tree growth occurred, mainly influenced by the increase in CWD and the decrease in winter-spring rainfall. In addition, a positive (negative) relationship was showed between PC1 growth-PDSI and PC1 growth-ENSO (growth-SAM), that is, growth increases (decreases) in the same direction as PDSI and ENSO (SAM). Despite the fact that sclerophyllous populations are highly resistant to drought events, we suggest that the sclerophyllous populations studied here experienced a generalized growth decline, and possibly the natural dynamics of their forests have been altered, mainly due to the accumulating effects of the unprecedented drought since 2010. Graphical abstract: [Figure not available: see fulltext.] © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. | |
| Sharp Increase of Extreme Turbidity Events Due To Deglaciation in the Subtropical Andes | Journal of Geophysical Research: Earth Surface | Vergara, I.; Garreaud, R.; Ayala, Á. | 2022 | Agua y Extremos | 10.1029/2021JF006584 | https://onlinelibrary.wiley.com/doi/10.1029/2021JF006584 | arte2021JF006584 | Vol: 127 Issue: 6 | 2169-9003, 2169-9011 | Thomson Reuters ISI (SCIE) | English | Climate change may affect sediment fluvial export from high mountain regions, leading to downstream environmental disruptions and direct impacts on human activities. In this paper, three decades (1990–2020) of turbidity measurements, along with climate and hydro-glaciological variables, were used to investigate the interannual and interdecadal variability in the number of extreme turbidity events (ETE) in the glacierized Maipo River basin, located in the western subtropical Andes. ETE are defined as a sequence of days (most often 1 or 2) during which the daily maximum turbidity was in the 99% quantile of the entire study period. Some of these events compromised the drinking water provision for the city of Santiago, with more than 6 million inhabitants. ETE are more frequent during summer and are mostly associated with melt-favourable conditions. The number of ETE tends to increase in summers with large glacier ice melt and low snowmelt (outside or over glaciers). Most notable, the mean annual number of ETE exhibits a 6-fold increase in the last decade compared with the 1990–2010 period. After 2010, ETE also shifted their seasonal maximum from late spring to mid-summer and their occurrence became strongly coupled with large ice melt rates. We hypothesize that such regime change was caused by an enhanced hydrological connectivity of subglacial sediment pools that increased the sensitivity of the sediment system to glacier melt. The latter is in line with recent research and is consistent with the ongoing glacier retreat due to strong regional warming and drying. © 2022. American Geophysical Union. All Rights Reserved. | |
| Exploring the association between landslides and fluvial suspended sediment in a semi-arid basin in central Chile | Geomorphology | Vergara, I.; Garreaud, R.; Moreiras, S.; Araneo, D.; Beigt, D. | 2022 | Agua y Extremos | 10.1016/j.geomorph.2022.108129 | https://linkinghub.elsevier.com/retrieve/pii/S0169555X22000228 | 108129 | Vol: 402 | 0169-555X | Thomson Reuters ISI (SCIE) | English | The systematic monitoring of landslides is an essential input for their characterization and subsequent reduction of their risk. Along the western subtropical Andes, field monitoring is scarce, so alternative methods that can improve the monitoring are valuable. In this work, the capacity of fluvial suspended sediment to detect the occurrence of landslides in a basin was explored, emphasizing how the relationship varies depending on the hydro-sedimentological variable, the triggering causal factor and the landslide type. The values of suspended sediment concentration (SSC), water discharge (Q) and specific suspended sediment yield (SSY) associated with mass movements were collected from a fluviometric station, as well as maxima of these variables that were not associated with landslides. With these data, different General Linear Models were constructed considering possible non-linear effects of the covariates. Flow-type landslides triggered by rain (most of the events) are correctly predicted, especially using the linear effects of SSC and Q. For this mass movement type the prediction is suitable even for events triggered by isolated, short-lived rains, which are difficult to detect in mountainous areas with meteorological devices. © 2022 Elsevier B.V. | |
| Compensatory Transcriptional Response of Fischerella thermalis to Thermal Damage of the Photosynthetic Electron Transfer Chain | Molecules | Vergara-Barros, P.; Alcorta, J.; Casanova-Katny, A.; Nürnberg, D.; Díez, B. | 2022 | Zonas Costeras | 10.3390/molecules27238515 | https://www.mdpi.com/1420-3049/27/23/8515 | 8515 | Vol: 27 Issue: 23 | 1420-3049 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Key organisms in the environment, such as oxygenic photosynthetic primary producers (photosynthetic eukaryotes and cyanobacteria), are responsible for fixing most of the carbon globally. However, they are affected by environmental conditions, such as temperature, which in turn affect their distribution. Globally, the cyanobacterium Fischerella thermalis is one of the main primary producers in terrestrial hot springs with thermal gradients up to 60 °C, but the mechanisms by which F. thermalis maintains its photosynthetic activity at these high temperatures are not known. In this study, we used molecular approaches and bioinformatics, in addition to photophysiological analyses, to determine the genetic activity associated with the energy metabolism of F. thermalis both in situ and in high-temperature (40 °C to 65 °C) cultures. Our results show that photosynthesis of F. thermalis decays with temperature, while increased transcriptional activity of genes encoding photosystem II reaction center proteins, such as PsbA (D1), could help overcome thermal damage at up to 60 °C. We observed that F. thermalis tends to lose copies of the standard G4 D1 isoform while maintaining the recently described D1INT isoform, suggesting a preference for photoresistant isoforms in response to the thermal gradient. The transcriptional activity and metabolic characteristics of F. thermalis, as measured by metatranscriptomics, further suggest that carbon metabolism occurs in parallel with photosynthesis, thereby assisting in energy acquisition under high temperatures at which other photosynthetic organisms cannot survive. This study reveals that, to cope with the harsh conditions of hot springs, F. thermalis has several compensatory adaptations, and provides emerging evidence for mixotrophic metabolism as being potentially relevant to the thermotolerance of this species. Ultimately, this work increases our knowledge about thermal adaptation strategies of cyanobacteria. |
| Comité Científico de Cambio Climático: Desalinización: Oportunidades y desafíos para abordar la inseguridad hídrica en Chile. | Vicuña, S.; Daniele, L.; Farías, L.; González, H.; Marquet, P.; Palma-Behnke, R.; Stehr, A.; Urquiza, A.; Wagemann, E.; Arenas-Herrera, M.; Borquez, R.; Cornejo-Ponce, L.; Delgado, V.; Etcheberry, G.; Fragkou, M.; Fuster, R.; Gelcich, S.; Melo, O.; Monsalve, T.; Olivares, M.; Ramajo, L.; Ramirez-Pas... | 2022 | Ciudades Resilientes | https://repositoriodirplan.mop.gob.cl/biblioteca/items/b38407dc-f89b-45fb-a37b-ea0d02773e05 | 1-189 | Frente al problema de escasez hídrica forzada por el cambio climático en Chile, particularmente en la zona norte del país, se han instalado plantas desalinizadoras de distintos tamaños, con varias más en proceso de estudio y evaluación. La masificación de esta tecnología nos plantea el desafío de planificar su desarrollo futuro tomando decisiones con bases científicas considerando las ventajas y desventajas de este tipo de tecnología. El presente documento fue elaborado en respuesta a la solicitud formal del Ministerio de Medio Ambiente para que el Comité Asesor Ministerial Científico para el Cambio Climático (C4) redactase un informe sobre el desarrollo de plantas desalinizadoras en el país. A partir de dicha solicitud, el Comité trabajó recopilando antecedentes y organizando talleres de trabajo con la comunidad científica a lo largo de varias etapas. Como resultado se prepararon una serie de recomendaciones, no siempre consensuadas, acerca del desarrollo de esta tecnología en el país. | |||||||
| Evolution of Glacial Lake Cochrane During the Last Glacial Termination, Central Chilean Patagonia (∼47°S) | Frontiers in Earth Science | Vásquez, A.; Flores-Aqueveque, V.; Sagredo, E.; Hevia, R.; Villa-Martínez, R.; Moreno, P.; Antinao, J. | 2022 | Agua y Extremos | 10.3389/feart.2022.817775 | https://www.frontiersin.org/articles/10.3389/feart.2022.817775/full | 817775 | Vol: 10 | 2296-6463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Large ice-dammed lakes developed along the eastern margin of the Patagonian Ice Sheet (PIS) during the Last Glacial Termination (T1). Their spatial/temporal evolution, however, remains poorly constrained despite their importance for deciphering fluctuations of the shrinking PIS, isostatic adjustments, and climate forcing. Here we examine the distribution and age of shoreline features deposited or sculpted by Glacial Lake Cochrane (GLC) in the Lago Cochrane/Pueyrredón (LCP) basin, Central Patagonia, following recession of the LCP glacier lobe from its final Last Glacial Maximum (LGM) moraines. GLC drained initially toward the Atlantic Ocean and continuing ice shrinking opened new drainage routes allowing the discharge toward the Pacific Ocean. We identify five clusters of lake terraces, shorelines, and deltas between elevations ∼600–500 (N5), ∼470–400 (N4), ∼360–300 (N3), ∼230–220 (N2), and ∼180–170 masl (N1) throughout the LCP basin. The distribution of these clusters and associated glaciolacustrine deposits provide constraints for the evolving position of the damming glacier bodies. Elevation gradients within the landform clusters reveal glacio-isostatic adjustments that enable us to quantify the magnitude of deglacial rebound and construct isostatically corrected surfaces for the different phases in the evolution of GLC. Our chronology, based principally on radiocarbon dates from lake sediment cores and new OSL dating, suggests that these phases developed between ∼20.7–19.3 ka (N5), ∼19.3–14.8 ka (N4), ∼14.8–11.3 ka (N3), and shortly thereafter (N2 and N1). The N3 landforms are the most ubiquitous, well-preserved, and voluminous, attributes that resulted from a ∼3,500-year long period of glacial stability, enhanced sediment supply by peak precipitation regime, and profuse snow and ice melting during the most recent half of T1. This scenario differs from the cold and dry conditions that prevailed during the brief N5 phase and the moderate amount of precipitation during the N4 phase. We interpret the limited development of the N2 and N1 landforms as ephemeral stabilization events following the final and irreversible disappearance of GLC after N3. This event commenced shortly after the onset of an early Holocene westerly minimum at pan-Patagonian scale at ∼11.7 ka, contemporaneous with peak atmospheric and oceanic temperatures in the middle and high latitudes of the Southern Hemisphere. |
| Seed dispersal distance, seed morphology, and recruitment in the Chilean sclerophyllous tree Quillaja saponaria: implications for passive restoration in a semiarid ecosystem | Plant Ecology | Vásquez, I.; Miranda, A.; Delpiano, C.; Becerra, P. | 2022 | Cambio de Uso de Suelo | 10.1007/s11258-021-01207-4 | https://link.springer.com/10.1007/s11258-021-01207-4 | 273-283 | Vol: 223 Issue: 3 | 1385-0237, 1573-5052 | Thomson Reuters ISI (SCIE) | English | Recolonization of wind-dispersed tree species in degraded areas may decline with distance from remnant forest fragments because seed rain frequently decreases with distance from the seed source. However, regeneration of these species may be even more limited to sites close to the seed source if dispersal distance is negatively affected by seed mass, and germination probability is positively affected by seed mass. We evaluated these hypotheses in a Mediterranean-type ecosystem of central Chile, using the wind-dispersed tree species Quillaja saponaria. We assessed the seed rain curve in a degraded open area adjacent to a remnant forest fragment of this species, and related seed mass with dispersal distance from the seed source. Then, we evaluated the relationship between seed mass, germination, and seedling growth, and if seeds that fall nearer the seed source have greater germination probability. We found a decreasing seed rain with the distance from the seed source. Seed mass was not related to dispersal distance, although seeds with higher wing area dispersed further. Germination probability was significantly and positively related to the seed mass. We observed no significant relationship between distance and germination probability. We conclude that germination probability of this species does not vary along the seed rain curve, and that the recruitment density would be greater near the seed source only due to decreasing seed rain with distance. Our results suggest that this species has the potential to be passively restored in degraded areas, especially within the first 70 m from the remnant forest fragments. | |
| Analysis of Climate-Related Risks for Chile’s Coastal Settlements in the ARClim Web Platform | Water | Winckler, P.; Contreras-López, M.; Garreaud, R.; Meza, F.; Larraguibel, C.; Esparza, C.; Gelcich, S.; Falvey, M.; Mora, J. | 2022 | Agua y Extremos | 10.3390/w14223594 | https://www.mdpi.com/2073-4441/14/22/3594 | 3594 | Vol: 14 Issue: 22 | 2073-4441 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The web-based tool ARClim provides an atlas of climate change-related risk assessments spanning over 50 environmental and productive sectors in Chile. This paper illustrates the implementation of ARClim on two coastal sectors, operational downtime in fishing coves and flooding in coastal settlements, aiming to provide a tool to visualize comparative estimates of risk, which may enable decision makers and stakeholders to prioritize adaptation measures. The risk is calculated as a function of the hazard, exposure, and sensitivity. Exposure and sensitivity are characterized using present day information. To assess the hazard, wave climate for a historical period (1985–2004) and a projection (2026–2045) were modeled with six general circulation models (GCMs) for an RCP8.5 scenario. Similarly, sea-level rise was computed from 21 GCMs. Results show that the flooding hazard is mostly dependent on sea-level rise, with waves playing a minor role. However, the flooding risk is highly variable along the coast, due to differences in the exposure, which strongly depends on the population of each settlement. The analysis of increased operational downtime in fishing coves also shows risk, which is dependent of the size of each site. Lastly, limitations of the analysis and opportunities for improvement are discussed. |
| Impact of mining on the metal content of dust in indigenous villages of northern Chile | Environment International | Zanetta-Colombo, N.; Fleming, Z.; Gayo, E.; Manzano, C.; Panagi, M.; Valdés, J.; Siegmund, A. | 2022 | Ciudades Resilientes | 10.1016/j.envint.2022.107490 | https://linkinghub.elsevier.com/retrieve/pii/S0160412022004172 | 107490 | Vol: 169 | 0160-4120 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Indigenous communities from northern Chile have historically been exposed to the impacts of massive copper industrial activities conducted in the region. Some of the communities belonging to the Alto El Loa Indigenous Development Area are located less than 10 km from the “Talabre'' tailings dam, which contains residues from copper production and other metals that can be toxic to human health (e.g., As, Sb, Cd, Mo, Pb). Given the increasing demand of copper production to achieve net-zero emission scenarios and concomitant expansions of the tailings, the exposure to toxic metals is a latent risk to local communities. Despite the impact that copper production could generate on ancestral communities from northern Chile, studies and monitoring are limited and the results are often not made accessible for local communities. Here, we evaluate such risks by characterizing metal concentrations in dust collected from roofs and windows of houses from the Alto El Loa area. Our results showed that As, Sb, Cd, Cu, Mo, Ag, S, and Pb concentrations in these matrices can be connected to local copper mining activities. Additionally, air transport models indicate that high concentrations of toxic elements (As, Sb, and Cd) can be explained by the atmospheric transport of particles from the tailings in a NE direction up to 50 km away. Pollution indices and Health Risk Assessment suggested a highly contaminated region with a health risk for its inhabitants. Our analysis on a local scale seeks to make visible the case of northern Chile as a critical territory where actions should be taken to mitigate the effects of mining in the face of this new scenario of international demand for the raw materials necessary for the transition to a net-zero carbon global society. © 2022 The Authors |
| High-resolution inventory of atmospheric emissions from transport, industrial, energy, mining and residential activities in Chile | Earth System Science Data | Álamos, N.; Huneeus, N.; Opazo, M.; Osses, M.; Puja, S.; Pantoja, N.; Denier van der Gon, H.; Schueftan, A.; Reyes, R.; Calvo, R. | 2022 | Ciudades Resilientes | 10.5194/essd-14-361-2022 | https://essd.copernicus.org/articles/14/361/2022/ | 361-379 | Vol: 14 Issue: 1 | 1866-3516 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Abstract. This study presents the first high-resolution national inventory of anthropogenic emissions for Chile (Inventario Nacional de Emisiones Antropogénicas, INEMA). Emissions for the vehicular, industrial, energy, mining and residential sectors are estimated for the period 2015–2017 and spatially distributed onto a high-resolution grid (approximately 1 km×1 km). The pollutants included are CO2, NOx, SO2, CO, VOCs (volatile organic compounds), NH3 and particulate matter (PM10 and PM2.5) for all sectors. CH4 and black carbon are included for transport and residential sources, while arsenic, benzene, mercury, lead, toluene, and polychlorinated dibenzo-p-dioxins and furan (PCDD/F) are estimated for energy, mining and industrial sources. New activity data and emissions factors are compiled to estimate emissions, which are subsequently spatially distributed using census data and Chile's road network information. The estimated annual average total national emissions of PM10 and PM2.5 during the study period are 191 and 173kt a−1 (kilotons per year), respectively. The residential sector is responsible for over 90 % of these emissions. This sector also emits 81 % and 87 % of total CO and VOC, respectively. On the other hand, the energy and industry sectors contribute significantly to NH3, SO2 and CO2 emissions, while the transport sector dominates NOx and CO2 emissions, and the mining sector dominates SO2 emissions. In general, emissions of anthropogenic air pollutants and CO2 in northern Chile are dominated by mining activities as well as thermoelectric power plants, while in central Chile the dominant sources are transport and residential emissions. The latter also mostly dominates emissions in southern Chile, which has a much colder climate. Preliminary analysis revealed the dominant role of the emission factors in the final emission uncertainty. Nevertheless, uncertainty in activity data also contributes as suggested by the difference in CO2 emissions between INEMA and EDGAR (Emission Database for Global Atmospheric Research). A comparison between these two inventories also revealed considerable differences for all pollutants in terms of magnitude and sectoral contribution, especially for the residential sector. EDGAR presents larger emissions for most of the pollutants except for CH4 and PM2.5. The differences between both inventories can partly be explained by the use of different emission factors, in particular for the residential sector, where emission factors incorporate information on firewood and local operation conditions. Although both inventories use similar emission factors, differences in CO2 emissions between both inventories indicate biases in the quantification of the activity. This inventory (available at https://doi.org/10.5281/zenodo.4784286, Alamos et al., 2021) will support the design of policies that seek to mitigate climate change and improve air quality by providing policymakers, stakeholders and scientists with qualified scientific spatially explicit emission information. |
| A distributed resistance inverse method for flow obstacle identification from internal velocity measurements | Inverse Problems | Aguayo, J.; Bertoglio, C.; Osses, A. | 2021 | Ciudades Resilientes | 10.1088/1361-6420/abced8 | https://iopscience.iop.org/article/10.1088/1361-6420/abced8 | 025010 | Vol: 37 Issue: 2 | 0266-5611, 1361-6420 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | We present a penalization parameter method for obstacle identification in an incompressible fluid flow for a modified version of the Oseen equations. The proposed method consists in adding a high resistance potential to the system such that some subset of its boundary support represents the obstacle. This allows to work in a fixed domain and highly simplify the solution of the inverse problem via some suitable cost functional. Existence of minimizers and first and second order optimality conditions are derived through the differentiability of the solutions of the Oseen equation with respect to the potential. Finally, several numerical experiments using Navier–Stokes flow illustrate the applicability of the method, for the localization of a bi-dimensional cardiac valve from MRI and ultrasound flow type imaging data. |
| Hydrological droughts in the southern Andes (40–45°S) from an ensemble experiment using CMIP5 and CMIP6 models | Scientific Reports | Aguayo, R.; León-Muñoz, J.; Garreaud, R.; Montecinos, A. | 2021 | Agua y Extremos | 10.1038/s41598-021-84807-4 | http://www.nature.com/articles/s41598-021-84807-4 | 5530 | Vol: 11 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The decrease in freshwater input to the coastal system of the Southern Andes (40–45°S) during the last decades has altered the physicochemical characteristics of the coastal water column, causing significant environmental, social and economic consequences. Considering these impacts, the objectives were to analyze historical severe droughts and their climate drivers, and to evaluate the hydrological impacts of climate change in the intermediate future (2040–2070). Hydrological modelling was performed in the Puelo River basin (41°S) using the Water Evaluation and Planning (WEAP) model. The hydrological response and its uncertainty were compared using different combinations of CMIP projects (n = 2), climate models (n = 5), scenarios (n = 3) and univariate statistical downscaling methods (n = 3). The 90 scenarios projected increases in the duration, hydrological deficit and frequency of severe droughts of varying duration (1 to 6 months). The three downscaling methodologies converged to similar results, with no significant differences between them. In contrast, the hydroclimatic projections obtained with the CMIP6 and CMIP5 models found significant climatic (greater trends in summer and autumn) and hydrological (longer droughts) differences. It is recommended that future climate impact assessments adapt the new simulations as more CMIP6 models become available. |
| Recent Changes in the Low-Level Jet along the Subtropical West Coast of South America | Atmosphere | Aguirre, C.; Flores-Aqueveque, V.; Vilches, P.; Vásquez, A.; Rutllant, J.; Garreaud, R. | 2021 | Agua y Extremos; Zonas Costeras | 10.3390/atmos12040465 | https://www.mdpi.com/2073-4433/12/4/465 | 465 | Vol: 12 Issue: 4 | 2073-4433 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Surface winds along the subtropical west coast of South America are characterized by the quasi-weekly occurrences of low-level jet events. These short lived but intense wind events impact the coastal ocean environment. Hence, identifying long-term trends in the coastal low-level jet (CLLJ) is essential for understanding changes in marine ecosystems. Here we use ERA5 reanalysis (1979–2019) and an objective algorithm to track anticyclones to investigate recent changes in CLLJ events off central Chile (25–43 °S). Results present evidence that the number of days with intense wind (≥10 ms−1), and the number and duration of CLLJ events have significantly changed off central Chile in recent decades. There is an increase in the number of CLLJ events in the whole study area during winter (June-July-August; JJA), while during summer (December–January–February; DJF) a decrease is observed at lower latitudes (29–34 °S), and an increase is found at the southern boundary of the Humboldt system. We suggest that changes in the central pressures and frequency of extratropical, migratory anticyclones that reach the coast of South America, which force CLLJs, have played an important role in the recent CLLJ changes observed in this region. |
| High-Frequency Variability of the Surface Ocean Properties Off Central Chile During the Upwelling Season | Frontiers in Marine Science | Aguirre, C.; Garreaud, R.; Belmar, L.; Farías, L.; Ramajo, L.; Barrera, F. | 2021 | Agua y Extremos; Zonas Costeras | 10.3389/fmars.2021.702051 | https://www.frontiersin.org/articles/10.3389/fmars.2021.702051/full | 702051 | Vol: 8 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The ocean off south-central Chile is subject to seasonal upwelling whose intensity is mainly controlled by the latitudinal migration of the southeast Pacific subtropical anticyclone. During austral spring and summer, the mean flow is equatorward favoring coastal upwelling, but periods of strong southerly winds are intermixed with periods of relaxed southerlies or weak northerly winds (downwelling favorable). This sub-seasonal, high-frequency variability of the coastal winds results in pronounced changes in oceanographic conditions and air-sea heat and gas exchanges, whose quantitative description has been limited by the lack of in-situ monitoring. In this study, high frequency fluctuations of meteorological, oceanographic and biogeochemical near surface variables were analyzed during two consecutive upwelling seasons (2016–17 and 2017–18) using observations from a coastal buoy located in the continental shelf off south-central Chile (36.4°S, 73°W), ∼10 km off the coast. The radiative-driven diel cycle is noticeable in meteorological variables but less pronounced for oceanographic and biogeochemical variables [ocean temperature, nitrate (NO 3 −), partial pressure of carbon dioxide ( p CO 2 sea ), pH, dissolved oxygen (DO)]. Fluorescence, as a proxy of chlorophyll- a , showed diel variations more controlled by biological processes. In the synoptic scale, 23 active upwelling events (strong southerlies, lasting between 2 and 15 days, 6 days in average) were identified, alternated with periods of relaxed southerlies of shorter duration (4.5 days in average). Upwelling events were related to the development of an atmospheric low-level coastal jet in response to an intense along-shore pressure gradient. Physical and biogeochemical surface seawater properties responded to upwelling favorable wind stress with approximately a 12-h lag. During upwelling events, SST, DO and pH decrease, while NO 3 −, p CO 2 sea , and air-sea fluxes increases. During the relaxed southerly wind periods, opposite tendencies were observed. The fluorescence response to wind variations is complex and diverse, but in many cases there was a reduction in the phytoplankton biomass during the upwelling events followed by higher values during wind relaxations. The sub-seasonal variability of the coastal ocean characterized here is important for biogeochemical and productivity studies. |
| Ecogenomics and Adaptation Strategies of Southern Ocean Viral Communities | mSystems | Alarcón-Schumacher, T.; Guajardo-Leiva, S.; Martinez-Garcia, M.; Díez, B. | 2021 | Zonas Costeras | 10.1128/mSystems.00396-21 | https://journals.asm.org/doi/10.1128/mSystems.00396-21 | e00396-21 | Vol: 6 Issue: 4 | 2379-5077 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Viruses are the most abundant biologic entities in marine systems and strongly influence the microbial community composition and diversity. However, little is known about viral communities’ adaptation and diversification in the ocean. , ABSTRACT The Southern Ocean (SO) represents up to one-fifth of the total carbon drawdown worldwide. Intense selective pressures (low temperature, high UV radiation, and strong seasonality) and physical isolation characterize the SO, serving as a “natural” laboratory for the study of ecogenomics and unique adaptations of endemic viral populations. Here, we report 2,416 novel viral genomes from the SO, obtained from newly sequenced viral metagenomes in combination with mining of publicly available data sets, which represents a 25% increase in the SO viral genomes reported to date. They comprised 567 viral clusters (defined as approximately genus-level groups), with 186 genera endemic to the SO, demonstrating that the SO viral community is predominantly constituted by a large pool of genetically divergent viral species from widespread viral families. The predicted proteome from SO viruses revealed that several protein clusters related to cold-shock-event responses and quorum-sensing mechanisms involved in the lysogenic-lytic cycle shift decision were under positive selection, which is ultimately important for fine adaptation of viral populations in response to the strong selective pressures of the SO. Finally, changes in the hydrophobicity patterns and amino acid frequencies suggested marked temperature-driven genetic selection of the SO viral proteome. Our data provide valuable insights into how viruses adapt and remain successful in this extreme polar marine environment. IMPORTANCE Viruses are the most abundant biologic entities in marine systems and strongly influence the microbial community composition and diversity. However, little is known about viral communities’ adaptation and diversification in the ocean. In this work, we take advantage of the geographical isolation and the intense selective pressures of the SO, to which viruses are exposed, to identify potential viral adaptations due to positive environmental selection and dispersal limitation. To that end, we recovered more than two thousand novel viral genomes, revealing a high degree of divergence in these SO endemic communities. Furthermore, we describe remarkable viral adaptations in amino acid frequencies and accessory proteins related to cold shock response and quorum sensing that allow them to thrive at lower temperatures. Consequently, our work greatly expands the understanding of the diversification of the viral communities of the SO and their particular adaptations to low temperatures. |
| Coastal Bacterial Community Response to Glacier Melting in the Western Antarctic Peninsula | Microorganisms | Alcamán-Arias, M.; Fuentes-Alburquenque, S.; Vergara-Barros, P.; Cifuentes-Anticevic, J.; Verdugo, J.; Polz, M.; Farías, L.; Pedrós-Alió, C.; Díez, B. | 2021 | Zonas Costeras | 10.3390/microorganisms9010088 | https://www.mdpi.com/2076-2607/9/1/88 | 88 | Vol: 9 Issue: 1 | 2076-2607 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Current warming in the Western Antarctic Peninsula (WAP) has multiple effects on the marine ecosystem, modifying the trophic web and the nutrient regime. In this study, the effect of decreased surface salinity on the marine microbial community as a consequence of freshening from nearby glaciers was investigated in Chile Bay, Greenwich Island, WAP. In the summer of 2016, samples were collected from glacier ice and transects along the bay for 16S rRNA gene sequencing, while in situ dilution experiments were conducted and analyzed using 16S rRNA gene sequencing and metatranscriptomic analysis. The results reveal that certain common seawater genera, such as Polaribacter, Pseudoalteromonas and HTCC2207, responded positively to decreased salinity in both the bay transect and experiments. The relative abundance of these bacteria slightly decreased, but their functional activity was maintained and increased the over time in the dilution experiments. However, while ice bacteria, such as Flavobacterium and Polaromonas, tolerated the increased salinity after mixing with seawater, their gene expression decreased considerably. We suggest that these bacterial taxa could be defined as sentinels of freshening events in the Antarctic coastal system. Furthermore, these results suggest that a significant portion of the microbial community is resilient and can adapt to disturbances, such as freshening due to the warming effect of climate change in Antarctica. |
| Learning from Each Other: An Experience of Capturing Learning for Adaptation to Climate Change | The International Journal of Climate Change: Impacts and Responses | Aldunce, P.; Lillo-Ortega, G.; Araya-Valenzuela, D.; Adler, C.; Ugarte, A. | 2021 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.18848/1835-7156/CGP/v13i01/75-90 | https://cgscholar.com/bookstore/works/learning-from-each-other | 75-90 | Vol: 13 Issue: 1 | 1835-7156 | The International Journal of Climate Change: Impacts and Responses | English | Local communities are the populations most exposed and the first to respond to the impacts of climate change, and their response capacity depends on several factors. Knowledge acquired about adaptation is one of the most relevant of such determinants. The present study advances an understanding of what people know (or do not know) about climate change adaptation, adaptation measures, and criteria for evaluating adaptation. The applied case study, related to the Chilean Mega Drought, involved a series of workshops carried out to evaluate adaptation practices. Questionnaires, including open questions, applied both before and after the workshop the observation of new learning results from the workshop participation. Results indicate a major knowledge gap in regard to relevant variables for evaluating adaptation practices. New knowledge was gained by the workshop participants, primarily regarding those variables but also related to adaptation practices implemented by other participants. This study provides helpful insights for identifying knowledge gaps and directing efforts to inform adaptation theory and strengthen adaptation practice. © Common Ground Research Networks, Paulina Aldunce, Gloria Lillo-Ortega, Dámare Araya-Valenzuela, Carolina Adler, Ana María Ugarte, All Rights Reserved. | |
| Evaluating adaptation to drought in a changing climate: experience at the local scale in the Aconcagua Valley | Climate and Development | Aldunce, P.; Lillo-Ortega, G.; Araya-Valenzuela, D.; Maldonado-Portilla, P.; Gallardo, L. | 2021 | Agua y Extremos; Ciudades Resilientes | 10.1080/17565529.2021.1893150 | https://www.tandfonline.com/doi/full/10.1080/17565529.2021.1893150 | 121-132 | Vol: 14 Issue: 2 | 1756-5529, 1756-5537 | Thomson Reuters ISI (SSCI) | English | Since 2010, a severe drought has affected central Chile, resulting in losses that prompt the need to evaluate and improve adaptation responses. The evaluation process requires the engagement of multiple actors in order to collect knowledge of their experiences and to inform future design and implementation of adaptation responses. A case study was conducted in four counties of the Aconcagua Valley, Chile, to evaluate the usefulness of existing drought response measures, and to identify strengths and weaknesses, and relevant actors’ recommendations for overcoming them. We applied the Index for the Usefulness of Adaptation Practices (IUPA), a multi-criteria tool that systematically identifies the perceived usefulness of measures. The most salient strengths of the evaluated measures were: replicability, pertinence, and efficacy; representing key factors that could facilitate the implementation of drought responses in similar contexts. The most salient weaknesses were: lack of integration with other policy domains and projects, low environmental protection, diminished autonomy in decision-making, and inequity. Proposed recommendations to overcome these weaknesses have real potential for implementation because they emerged from local actors. Results present empirical evidence of the utility of participatory approaches for a context-specific evaluation of measures, contributing to enhance adaptation to climate variability and change. | |
| Enfoque Transformación: Adaptación | Aldunce, P.; Rojas, M.; Guevara, G.; Álvarez, C.; Billi, M.; Ibarra, C.; Sapiains, R. | 2021 | Agua y Extremos; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://www.cr2.cl/wp-content/uploads/2021/10/transformacion_adaptacion.pdf | El presente documento es un marco conceptual para la incorporación del enfoque de transformación en las investigaciones de cambio climático con énfasis en la adaptación y tiene el propósito de apoyar la aplicación del enfoque al trabajo de investigación del (CR)2 a través de los Temas Integrativos de Floración de Algas Nocivas (FAN), de Seguridad Hídrica (TISHi) y de Gobernanza climática de los elementos. El enfoque de transformación se compone de distintos conceptos y alcances, de los que este documento presenta lo medular en tres secciones: (1) Conceptualización de la transformación y conceptos relacionados; (2) Transformación y adaptación; y (3) Preguntas orientadoras para la implementación del enfoque de la transformación. |
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| La emergencia de los territorios y la condición socioambiental: poder, naturaleza, ciudadanía y la necesidad de conocimiento transdisciplinar | Revista Anales de la Universidad de Chile | Aliste, E. | 2021 | 10.5354/0717-8883.2021.66069 | https://anales.uchile.cl/index.php/ANUC/article/view/66069 | 197-206 | Vol: 19 Issue: 7 | 0717-8883 | Latindex | Escuchar a los territorios. Dejar que hablen los territorios. No actuar sin el consentimiento de los territorios. Algunas frases como las anteriores o de similar talante se han hecho cada vez más comunes en los últimos años, posicionándose con fuerza y convicción como expresión clara de que tras esta idea hay una conceptualización compleja que abarca muchísimo más que una unidad espacial capaz de ser plasmada en una cartografía remarcando sus delimitaciones. De ello muchísimas discusiones han dado cuenta en los últimos años, pero hay algo aún más poderoso y relevante en torno a aquello, y se trata del modo en que la expresión se usa por estos días, dando cuenta de algo que hace sentido, da coherencia y se entiende como dialogante entre quienes habitan y se sienten parte de un espacio que se significa y apropia como parte extendida de una cotidianidad | |||
| Conocimiento técnico-científico en el conflicto hídrico en Chile | Revista Mad | Allendes, A.; Silva, F.; Fragkou, M.; Moraga, P.; Urquiza, A. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.5354/0719-0527.2021.65874 | https://revistas.uchile.cl/index.php/RMAD/article/view/65874 | 99-119 | Issue: 45 | 0718-0527 | Thomson Reuters ISI (ESCI) | Spanish | El presente artículo propone un análisis del uso del cono | |
| Progressive water deficits during multiyear droughts in basins with long hydrological memory in Chile | Hydrology and Earth System Sciences | Alvarez-Garreton, C.; Boisier, J.; Garreaud, R.; Seibert, J.; Vis, M. | 2021 | Agua y Extremos | 10.5194/hess-25-429-2021 | https://hess.copernicus.org/articles/25/429/2021/ | 429-446 | Vol: 25 Issue: 1 | 1607-7938 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | A decade-long (2010–2020) period with precipitation deficits in central–south Chile (30–41∘ S), the so-called megadrought (MD), has led to streamflow depletions of larger amplitude than expected from precipitation anomalies, indicating an intensification in drought propagation. We analysed the catchment characteristics and runoff mechanisms modulating such intensification by using the CAMELS-CL dataset and simulations from the HBV hydrological model. We compared annual precipitation–runoff (P–R) relationships before and during the MD across 106 basins with varying snow-/rainfall regimes and identified those catchments where drought propagation was intensified. Our results show that catchments' hydrological memory – modulated by snow and groundwater – is a key control of drought propagation. Snow-dominated catchments (30–35∘ S) feature larger groundwater contribution to streamflow than pluvial basins, which we relate to the infiltration of snowmelt over the Western Andean Front. This leads to longer memory in these basins, represented by a significative correlation between autumn streamflow (when snow has already melted) and the precipitation from the preceding year. Hence, under persistent drought conditions, snow-dominated catchments accumulate the effects of precipitation deficits and progressively generate less water, compared with their historical behaviour, notably affecting central Chile, a region with limited water supply and which concentrates most of the country's population and water demands. Finally, we addressed a general question: what is worse – an extreme single-year drought or a persistent moderate drought? In snow-dominated basins, where water provision strongly depends on both the current and previous precipitation seasons, an extreme drought induces larger absolute streamflow deficits; however persistent deficits induce a more intensified propagation of the meteorological drought. Hence, the worst scenario would be an extreme meteorological drought following consecutive years of precipitation below average, as occurred in 2019. In pluvial basins of southern Chile (35–41∘ S), hydrologic memory is still an important factor, but water supply is more strongly dependant on the meteorological conditions of the current year, and therefore an extreme drought would have a higher impact on water supply than a persistent but moderate drought. |
| Radiocarbon bomb-peak signal in tree-rings from the tropical Andes register low latitude atmospheric dynamics in the Southern Hemisphere | Science of The Total Environment | Ancapichún, S.; De Pol-Holz, R.; Christie, D.; Santos, G.; Collado-Fabbri, S.; Garreaud, R.; Lambert, F.; Orfanoz-Cheuquelaf, A.; Rojas, M.; Southon, J.; Turnbull, J.; Creasman, P. | 2021 | Agua y Extremos; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1016/j.scitotenv.2021.145126 | https://linkinghub.elsevier.com/retrieve/pii/S0048969721001923 | 145126 | Vol: 774 | 00489697 | Thomson Reuters ISI (SCIE) | English | South American tropical climate is strongly related to the tropical low-pressure belt associated with the South American monsoon system. Despite its central societal role as a modulating agent of rainfall in tropical South America, its long-term dynamical variability is still poorly understood. Here we combine a new (and world's highest) tree-ring 14C record from the Altiplano plateau in the central Andes with other 14C records from the Southern Hemisphere during the second half of the 20th century in order to elucidate the latitudinal gradients associated with the dissemination of the bomb 14C signal. Our tree-ring 14C record faithfully captured the bomb signal of the 1960's with an excellent match to atmospheric 14C measured in New Zealand but with significant differences with a recent record from Southeast Brazil located at almost equal latitude. These results imply that the spreading of the bomb signal throughout the Southern Hemisphere was a complex process that depended on atmospheric dynamics and surface topography generating reversals on the expected north-south gradient in certain years. We applied air-parcel modeling based on climate data to disentangle their different geographical provenances and their preformed (reservoir affected) radiocarbon content. We found that air parcel trajectories arriving at the Altiplano during the bomb period were sourced i) from the boundary layer in contact with the Pacific Ocean (41%), ii) from the upper troposphere (air above the boundary layer, with no contact with oceanic or continental carbon reservoirs) (38%) and iii) from the Amazon basin (21%). Based on these results we estimated the ∆14C endmember values for the different carbon reservoirs affecting our record which suggest that the Amazon basin biospheric 14C isoflux could have been reversed from negative to positive as early as the beginning of the 1970's. This would imply a much faster carbon turnover rate in the Amazon than previously modelled. | |
| Spatiotemporal Peatland Productivity and Climate Relationships Across the Western South American Altiplano | Journal of Geophysical Research: Biogeosciences | Anderson, T.; Christie, D.; Chávez, R.; Olea, M.; Anchukaitis, K. | 2021 | Agua y Extremos | 10.1029/2020JG005994 | https://onlinelibrary.wiley.com/doi/10.1029/2020JG005994 | art: e2020JG005994 | Vol: 126 Issue: 6 | 2169-8953, 2169-8961 | Thomson Reuters ISI (SCIE) | English | The South American Altiplano is one of the largest semiarid high-altitude plateaus in the world. Within the Altiplano, peatlands known as “bofedales” are important components of regional hydrology and provide key water resources and ecosystem services to Andean communities. Warming temperatures, changes in hydroclimate, and shifting atmospheric circulation patterns all affect peatland dynamics and hydrology. It is therefore urgent to better understand the relationships between climate variability and the spatiotemporal variations in peatland productivity across the Altiplano. Here, we explore climate influences on peatland vegetation using 31 years of Landsat data. We focus specifically on the bofedal network in the western Altiplano, the driest sector of the plateau, and use the satellite-derived Normalized Difference Vegetation Index (NDVI) as an indicator of productivity. We develop temporally and spatially continuous NDVI products at multiple scales in order to evaluate relationships with climate variables over the past three decades. We demonstrate that cumulative precipitation and snow persistence over the prior 2 years are strongly associated with growing season productivity. A step change in peatland productivity between 2013–2015 drives an increasing trend in NDVI and is likely a response to consecutive years of anomalously high snow accumulation and rainfall. Early summer minimum temperatures emerge as a secondary influence on productivity. Understanding large-scale productivity dynamics and characterizing the response of bofedales to climate variability over the last three decades provides a baseline to monitor the responses of Andean peatlands to climate change. | |
| Fire-induced loss of the world’s most biodiverse forests in Latin America | Science Advances | Armenteras, D.; Dávalos, L.; Barreto, J.; Miranda, A.; Hernández-Moreno, A.; Zamorano-Elgueta, C.; González-Delgado, T.; Meza-Elizalde, M.; Retana, J. | 2021 | Cambio de Uso de Suelo | 10.1126/sciadv.abd3357 | https://advances.sciencemag.org/lookup/doi/10.1126/sciadv.abd3357 | eabd3357 | Vol: 7 Issue: 33 | 2375-2548 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Fire plays a dominant role in deforestation, particularly in the tropics, but the relative extent of transformations and influence of fire frequency on eventual forest loss remain unclear. Here, we analyze the frequency of fire and its influence on postfire forest trajectories between 2001 and 2018. We account for ~1.1% of Latin American forests burnt in 2002–2003 (8,465,850 ha). Although 40.1% of forests (3,393,250 ha) burned only once, by 2018, ~48% of the evergreen forests converted to other, primarily grass-dominated uses. While greater fire frequency yielded more transformation, our results reveal the staggering impact of even a single fire. Increasing fire frequency imposes greater risks of irreversible forest loss, transforming forests into ecosystems increasingly vulnerable to degradation. Reversing this trend is indispensable to both mitigate and adapt to climate change globally. As climate change transforms fire regimes across the region, key actions are needed to conserve Latin American forests. |
| Lipschitz Stability for Backward Heat Equation with Application to Fluorescence Microscopy | SIAM Journal on Mathematical Analysis | Arratia, P.; Courdurier, M.; Cueva, E.; Osses, A.; Palacios, B. | 2021 | Ciudades Resilientes | 10.1137/20M1374183 | https://epubs.siam.org/doi/10.1137/20M1374183 | 5948-5978 | Vol: 53 Issue: 5 | 0036-1410, 1095-7154 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | In this work we study a Lipschitz stability result in the reconstruction of a compactly supported initial temperature for the heat equation in Rn, from measurements along a positive time interval and over an open set containing its support. We employ a nonconstructive method which ensures the existence of the stability constant, but it is not explicit in terms of the parameters of the problem. The main ingredients in our method are the compactness of support of the initial condition and the explicit dependency of solutions to the heat equation with respect to it. By means of Carleman estimates we obtain an analogous result for the case when the observation is made along an exterior region ω × (τ, T), such that the unobserved part Rn\ω is bounded. In the latter setting, the method of Carleman estimates gives a general conditional logarithmic stability result when initial temperatures belong to a certain admissible set, without the assumption of compactness of support and allowing an explicit stability constant. Furthermore, we apply these results to deduce similar stability inequalities for the heat equation in R and with measurements available on a curve contained in R ×[0, ∞), leading to the derivation of stability estimates for an inverse problem arising in 2D fluorescence microscopy. In order to further understand this Lipschitz stability, in particular, the magnitude of its stability constant with respect to the parameters of the problem, a numerical reconstruction is presented based on the construction of a linear system for the inverse problem in fluorescence microscopy. We investigate the stability constant by analyzing the condition number of the corresponding matrix. © 2021 Society for Industrial and Applied Mathematics |
| Climate change perception, vulnerability, and readiness: inter-country variability and emerging patterns in Latin America | Journal of Environmental Studies and Sciences | Azócar, G.; Billi, M.; Calvo, R.; Huneeus, N.; Lagos, M.; Sapiains, R.; Urquiza, A. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1007/s13412-020-00639-0 | http://link.springer.com/10.1007/s13412-020-00639-0 | 23-36 | Vol: 11 Issue: 1 | 2190-6483, 2190-6491 | Thomson Reuters ISI (ESCI) | All Open Access; Green Open Access | English | In Latin America, there is scarce comparative research on variables associated with the perception of climate change. This hinders the ability of governments to take mitigation and adaptation measures in the face of the phenomenon, as well as the ability of the population to cope with its effects. In order to fill that void, this research studies the relationship between climate change perception, vulnerability, and readiness in 17 countries of the region. To that end, perception indicators included in the Latinobarómetro 2017 survey are analyzed, contrasted with vulnerability and readiness indexes provided by the University of Notre Dame’s Global Adaptation Index. The analytical strategy includes the statistical description of the variables associated with the perception of climate change in countries of the region, clustering together those countries that display similar behavioral patterns in relation to their vulnerability and readiness indicators, as well as crosstabs with climate change indicators. The key findings indicate that it is possible to identify 3 patterns of behavior regarding the countries’ vulnerability and readiness, which account for high, intermediate, and low levels in those variables. These patterns indicate cross-cutting trends concerning variables such as the level of education and affinity for the market economy, as well as particularities differentiating each country from the rest. The main conclusion is the existence of a negative association between the affinity people express for the market economy and their acknowledgment of climate change as a relevant problem. © 2020, AESS. |
| On the selection of precipitation products for the regionalisation of hydrological model parameters | Hydrology and Earth System Sciences | Baez-Villanueva, O.; Zambrano-Bigiarini, M.; Mendoza, P.; McNamara, I.; Beck, H.; Thurner, J.; Nauditt, A.; Ribbe, L.; Thinh, N. | 2021 | Agua y Extremos | 10.5194/hess-25-5805-2021 | https://hess.copernicus.org/articles/25/5805/2021/ | 5805-5837 | Vol: 25 Issue: 11 | 1607-7938 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Over the past decades, novel parameter regionalisation techniques have been developed to predict streamflow in data-scarce regions. In this paper, we examined how the choice of gridded daily precipitation (P) products affects the relative performance of three well-known parameter regionalisation techniques (spatial proximity, feature similarity, and parameter regression) over 100 near-natural catchments with diverse hydrological regimes across Chile. We set up and calibrated a conceptual semi-distributed HBV-like hydrological model (TUWmodel) for each catchment, using four P products (CR2MET, RF-MEP, ERA5, and MSWEPv2.8). We assessed the ability of these regionalisation techniques to transfer the parameters of a rainfall-runoff model, implementing a leave-one-out cross-validation procedure for each P product. Despite differences in the spatio-temporal distribution of P, all products provided good performance during calibration (median Kling–Gupta efficiencies (KGE′s) > 0.77), two independent verification periods (median KGE′s >0.70 and 0.61, for near-normal and dry conditions, respectively), and regionalisation (median KGE′s for the best method ranging from 0.56 to 0.63). We show how model calibration is able to compensate, to some extent, differences between P forcings by adjusting model parameters and thus the water balance components. Overall, feature similarity provided the best results, followed by spatial proximity, while parameter regression resulted in the worst performance, reinforcing the importance of transferring complete model parameter sets to ungauged catchments. Our results suggest that (i) merging P products and ground-based measurements does not necessarily translate into an improved hydrologic model performance; (ii) the spatial resolution of P products does not substantially affect the regionalisation performance; (iii) a P product that provides the best individual model performance during calibration and verification does not necessarily yield the best performance in terms of parameter regionalisation; and (iv) the model parameters and the performance of regionalisation methods are affected by the hydrological regime, with the best results for spatial proximity and feature similarity obtained for rain-dominated catchments with a minor snowmelt component. |
| Niche differentiation of Dinophysis acuta and D. acuminata in a stratified fjord | Harmful Algae | Baldrich, Á.; Pérez-Santos, I.; Álvarez, G.; Reguera, B.; Fernández-Pena, C.; Rodríguez-Villegas, C.; Araya, M.; Álvarez, F.; Barrera, F.; Karasiewicz, S.; Díaz, P. | 2021 | Zonas Costeras | 10.1016/j.hal.2021.102010 | https://linkinghub.elsevier.com/retrieve/pii/S1568988321000378 | 102010 | Vol: 103 | 15689883 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Dinophysis acuta and D. acuminata are associated with lipophilic toxins in Southern Chile. Blooms of the two species coincided during summer 2019 in a highly stratified fjord system (Puyuhuapi, Chilean Patagonia). High vertical resolution measurements of physical parameters were carried out during 48 h sampling to i) explore physiological status (e.g., division rates, toxin content) and ii) illustrate the fine scale distribution of D. acuta and D. acuminata populations with a focus on water column structure and co-occurring plastid-bearing ciliates. The species-specific resources and regulators defining the realized niches (sensu Hutchinson) of the two species were identified. Differences in vertical distribution, daily vertical migration and in situ division rates (with record values, 0.76 d−1, in D. acuta), in response to the environmental conditions and potential prey availability, revealed their niche differences. The Outlying Mean Index (OMI) analysis showed that the realized niche of D. acuta (cell maximum 7 × 103 cells L−1 within the pycnocline) was characterized by sub-surface estuarine waters (salinity 23 – 25), lower values of turbulence and PAR, and a narrow niche breath. In contrast, the realized niche of D. acuminata (cell maximum 6.8 × 103 cells L−1 just above the pycnocline) was characterized by fresher (salinity 17 – 20) outflowing surface waters, with higher turbulence and light intensity and a wider niche breadth. Results from OMI and PERMANOVA analyses of co-occurring microplanktonic ciliates were compatible with the hypothesis of species such as those from genera Pseudotontonia and Strombidium constituting an alternative ciliate prey to Mesodinium. The D. acuta cell maximum was associated with DSP (OA and DTX-1) toxins and pectenotoxins; that of D. acuminata only with pectenotoxins. Results presented here contribute to a better understanding of the environmental drivers of species-specific blooms of Dinophysis and management of their distinct effects in Southern Chile. |
| Major atmospheric particulate matter sources for glaciers in Coquimbo Region, Chile | Environmental Science and Pollution Research | Barraza, F.; Lambert, F.; MacDonell, S.; Sinclair, K.; Fernandoy, F.; Jorquera, H. | 2021 | Ciudades Resilientes | 10.1007/s11356-021-12933-7 | https://link.springer.com/10.1007/s11356-021-12933-7 | 36817-36827 | Vol: 28 Issue: 27 | 0944-1344, 1614-7499 | Thomson Reuters ISI (SCIE) | English | Tapado Glacier is a subtropical mountain glacier in the Coquimbo region of Chile that has been continuously retreating during the last 60 years due to diminishing precipitation rates and rising temperatures and likely due to a currently unknown influence from atmospheric pollutant deposition. Climatic and meteorological impacts on this, and other, Andean glacier have been previously studied; however, cryosphere changes driven by aerosols are still largely unknown. To contribute to the understanding of the origin of aerosols and their dispersion, this study aims to identify natural and anthropogenic sources of air pollution deposited on the Tapado Glacier (4500–5536 m a.s.l.) and their transport by using a receptor model (positive matrix factorization) together with the concentration of major ions as proxies of air pollution deposited on this glacier. This model’s outcomes were complemented with daily wind backward trajectories computed for a whole year using the HYSPLYT meteorological model. Four sources were identified as the main contributors to major soluble ions in the Tapado surface snow. These sources are natural Aeolian dust (38%) from the Atacama Desert (including mining sites), natural weathered sulphates (27%), anthropogenic nitrates (25%), and coastal aerosols (10%). Coastal nitrate emissions and coastal aerosols are both sources with an important anthropogenic component, coming from La Serena and Coquimbo’s coastal cities. The crustal components and sulphate profiles are similar to detritus dispersed from the glacier after wind erosion. Although the glacier is located over 4000 m above sea level, anthropogenic pollutants reached this location. However, their contributions were smaller compared to natural contaminants. Our findings can likely be extended to the nearest glaciers in Northern Chile, which have similar potential contaminant sources from cities, ports, and thriving mining activity. However, these findings may not be suitable for southern Chilean glaciers, which are closer to bigger cities and to smoke from residential heating prevalent in winter months and wildfires during the summer. |
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| Water management or megadrought: what caused the Chilean Aculeo Lake drying? | Regional Environmental Change | Barría, P.; Chadwick, C.; Ocampo-Melgar, A.; Galleguillos, M.; Garreaud, R.; Díaz-Vasconcellos, R.; Poblete, D.; Rubio-Álvarez, E.; Poblete-Caballero, D. | 2021 | Agua y Extremos; Cambio de Uso de Suelo | 10.1007/s10113-021-01750-w | http://link.springer.com/10.1007/s10113-021-01750-w | 19 | Vol: 21 Issue: 1 | 1436-3798, 1436-378X | Thomson Reuters ISI (SCIE; SSCI) | English | The Aculeo Lake is an important natural reservoir of Central Chile, which provides valuable ecosystem services. This lake has suffered a rapid shrinkage of the water levels from year 2010 to 2018, and since October 2018, it is completely dry. This natural disaster is concurrent with a number of severe and uninterrupted drought years, along with sustained increases in water consumption associated to land use/land cover (LULC) changes. Severe water shortages and socio-environmental impacts were triggered by these changes, emphasizing the need to understand the causes of the lake desiccation to contribute in the design of future adaptation strategies. Thereby, the Water Evaluation and Planning (WEAP) hydrological model was used as a tool to quantify the water balance in the catchment. The model was run under a combination of three land use/land cover and two different climate scenarios that sample the cases with and without megadrought and with or without changes in land use. According to the results, the main triggering factor of the lake shrinkage is the severe megadrought, with annual rainfall deficits of about 38%, which resulted in amplified reductions in river flows (44%) and aquifer recharges (24%). The results indicate that the relative impact of the climate factor is more than 10 times larger than the impact of the observed LULC changes in the lake balance, highlighting the urgent need for adaptation strategies to deal with the projected drier futures. | |
| Water allocation under climate change | Elementa: Science of the Anthropocene | Barría, P.; Sandoval, I.; Guzman, C.; Chadwick, C.; Alvarez-Garreton, C.; Díaz-Vasconcellos, R.; Ocampo-Melgar, A.; Fuster, R. | 2021 | Agua y Extremos | 10.1525/elementa.2020.00131 | https://online.ucpress.edu/elementa/article/9/1/00131/117183/Water-allocation-under-climate-changeA-diagnosis | 00131 | Vol: 9 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Chile is positioned in the 20th rank of water availability per capita. Nonetheless, water security levels vary across the territory. Around 70% of the national population lives in arid and semiarid regions, where a persistent drought has been experienced over the last decade. This has led to water security problems including water shortages. The water allocation and trading system in Chile is based on a water use rights (WURs) market, with limited regulatory and supervisory mechanisms, where the volume to be granted as permanent and eventual WURs is calculated from statistical analyses of historical streamflow records if available, or from empirical estimations if they are not. This computation of WURs does not consider the nonstationarity of hydrological processes nor climatic projections. This study presents the first large sample diagnosis of water allocation system in Chile under climate change scenarios. This is based on novel anthropic intervention indices (IAI), which were computed as the ratio between the total granted water volume to the water availability within 87 basins in north-central and southern Chile (30°S–42°S). The IAI were evaluated for the historical period (1979–2019) and under modeled-based climatic projections (2055–2080). According to these IAI levels, to date, there are 20 out of 87 overallocated basins, which under the assumption that no further WURs will be granted in the future, increases up to 25 basins for the 2055–2080 period. The results show that, to date most of north-central Chilean catchments already have a large anthropic intervention degree, and the increases for the future period occurs mostly in the southern region of the country (approximately 38°S), which has been considered as possible source of water for large water transfer projects (i.e., water roads). These indices and diagnosis are proposed as a tool to help policy makers to address water scarcity under climate change. |
| Carleman-Based Reconstruction Algorithm for Waves | SIAM Journal on Numerical Analysis | Baudouin, L.; de Buhan, M.; Ervedoza, S.; Osses, A. | 2021 | Ciudades Resilientes | 10.1137/20M1315798 | https://epubs.siam.org/doi/10.1137/20M1315798 | 998-1039 | Vol: 59 Issue: 2 | 0036-1429, 1095-7170 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | We present a globally convergent numerical algorithm based on global Carleman estimates to reconstruct the speed of wave propagation in a bounded domain with Dirichlet boundary conditions from a single measurement of the boundary flux of the solutions in a finite time interval. The global convergence of the proposed algorithm naturally arises from the proof of the Lipschitz stability of the corresponding inverse problem for both sufficiently large observation time and boundary using global Carleman inequalities. The speed of propagation is supposed to be independent of time but varying in space with a trace and normal derivative known at the boundary and belonging to a certain admissible set that limits the speed fluctuations with respect to a given exterior point x0. In order to recover the speed, we also require a single experiment with null initial velocity and initial deformation having some monotonicity properties in the direction of x - x0. We perform numerical simulations in the discrete setting in order to illustrate and to validate the feasibility of the algorithm in both one and two dimensions in space. As proved theoretically, we verify that the numerical reconstruction is achieved for any admissible initial guess, even in the presence of small random disturbances on the measurements. © 2021 Society for Industrial and Applied Mathematics |
| Methodology to analyse the impact of an emissions trading system in Chile | Climate Policy | Benavides, C.; Díaz, M.; Ryan, R.; Gwinner, S.; Sierra, E. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1080/14693062.2021.1954869 | https://www.tandfonline.com/doi/full/10.1080/14693062.2021.1954869 | 1099-1110 | Vol: 21 Issue: 8 | 1469-3062, 1752-7457 | Thomson Reuters ISI (SSCI) | English | In the context of updating the 2015 Nationally Determined Contribution (NDC), the government of Chile has updated its estimates of compliance costs for a series of mitigation actions with an emphasis on the energy sector as the main source of its greenhouse gas emissions. Using the information developed in this process, we assess the impact on compliance costs of increasing the flexibility for sources by introducing different emissions trading schemes. For this we develop a detailed optimization model that represents the operational and investment decisions that could be taken by the energy generation, industrial and mining sectors if an Emissions Trading System (ETS) was implemented. An ETS with two cap and trade options is analysed together with an offset mechanism for sources not included in the ETS. Also, two policy goals are considered: a stringent 76% sectoral reduction goal in 2050 similar to Chile’s current strict NDC, and a more lax 46% goal similar to Chile’s initial 2015 NDC proposal. The results show that (i) cost reductions from increased flexibility for Chile’s current strict NDC are significant, and that offsets can play an important role; (ii) the stringency of the reduction goal affects the magnitude of the cost savings related to flexibility and, surprisingly, total abatement costs are negative (i.e. there are benefits) for the 46% reduction goal. In this latter case, the most significant cost reductions result from compelling firms to comply with their allowances in each sector, not increased flexibility. These results highlight the policy relevance of case by case analysis using a modelling approach similar to the one we develop here. |
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| Mapping water ecosystem services: Evaluating InVEST model predictions in data scarce regions | Environmental Modelling & Software | Benra, F.; De Frutos, A.; Gaglio, M.; Álvarez-Garretón, C.; Felipe-Lucia, M.; Bonn, A. | 2021 | Agua y Extremos | 10.1016/j.envsoft.2021.104982 | https://linkinghub.elsevier.com/retrieve/pii/S1364815221000256 | 104982 | Vol: 138 | 13648152 | Thomson Reuters ISI (SCIE) | English | Sustainable management of water ecosystem services requires reliable information to support decision making. We evaluate the performance of the InVEST Seasonal Water Yield Model (SWYM) against water monitoring records in 224 catchments in southern Chile. We run the SWYM in three years (1998, 2007 and 2013) to account for recent land-use change and climatic variations. We computed squared Pearson correlations between SWYM monthly quickflow predictions and streamflow observations and applied a generalized mixed‐effects model to evaluate annual estimations. Results show relatively low monthly correlations with marked latitudinal and temporal variations while annual estimates show a good match between observed and modeled values, especially for values under 1000 mm/year. Better predictions were observed in regions with high rainfall and in dry years while poorer predictions were found in snow dominated and drier regions. Our results improve SWYM performance and contribute to water supply and regulation decision-making, particularly in data scarce regions. | |
| Aporte de un sistema predictivo de contraloría médica en la gestión de licencias médicas electrónicas | Revista Chilena de Salud Pública | Bernales, B.; Bravo, S.; Causa, L.; Gómez, N.; Valdés, M. | 2021 | Ciudades Resilientes | 10.5354/0719-5281.2020.61265 | https://revistasaludpublica.uchile.cl/index.php/RCSP/article/view/61265 | 115 | Vol: 24 Issue: 2 | 0719-5281, 0717-3652 | Introducción: El retraso del procesamiento de las licencias médicas (LMs) representa un problema de salud pública en Chile, considerando que esto afecta el pago del subsidio a las personas destinado a realizar el reposo médico prescrito mientras no se pueda trabajar. El objetivo de este estudio fue explorar las diferencias en el tiempo de procesamiento de las licencias médicas electrónicas (LMEs) evaluadas por contraloría médica (CM) y las evaluadas por un sistema predictivo de contraloría médica (SPCM) basado en redes neuronales artificiales. Materiales y métodos: El tiempo de procesamiento de LMEs procesadas con SPCM fue comparado con el tiempo de procesamiento de LMEs examinadas solo con CM, usando curvas de Kaplan Meier, prueba de log-rank y modelos multivariados de Cox. Resultados: La tasa de procesamiento del SPCM fue entre 1,7 a 5,5 veces más rápida que la tasa de procesamiento de la CM, ajustando por potenciales confusores. Discusión: La implementación del SPCM permitió disminuir el tiempo de procesamiento de las LMEs, beneficiando a los trabajadores afiliados al seguro público. | |||
| Chemical Signals in Tree Rings from Northern Patagonia as Indicators of Calbuco Volcano Eruptions since the 16th Century | Forests | Bertin, L.; Christie, D.; Sheppard, P.; Muñoz, A.; Lara, A.; Alvarez, C. | 2021 | Agua y Extremos; Cambio de Uso de Suelo | 10.3390/f12101305 | https://www.mdpi.com/1999-4907/12/10/1305 | 1305 | Vol: 12 Issue: 10 | 1999-4907 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Calbuco volcano ranks third in the specific risk classification of volcanoes in Chile and has a detailed eruption record since 1853. During 2015, Calbuco had a sub-Plinian eruption with negative impacts in Chile and Argentina, highlighting the need to determine the long-term history of its activity at a high-resolution time scale to obtain a better understanding of its eruptive frequency. We developed a continuous eruptive record of Calbuco for the 1514–2016 period by dendrochemical analysis of Fitzroya cupressoides tree rings at a biennium resolution using inductively coupled plasma–mass spectrometry. After comparing the chemical record of 20 elements contained in tree rings with historical eruptions, one group exhibited positive anomalies during (Pb/Sn) and immediately after (Mo/P/Zn/Cu) eruptions, with a Volcanic Explosivity Index (VEI) ≥ 3, and so were classified as chemical tracers of past eruptions (TPE). The tree-ring width chronology also exhibited significant decreases in tree growth associated with eruptions of VEI ≥ 3. According to these records, we identified 11 new eruptive events of Calbuco, extending its eruptive chronology back to the 16th century and determining a mean eruptive frequency of ~23 years. Our results show the potential to use dendrochemical analysis to infer past volcanic eruptions in Northern Patagonia. This information provides a long-term perspective for assessing eruptive history in Northern Patagonia, with implications for territorial planning. |
| Tracing Social Movements' Influence Beyond Agenda-Setting: Waves of Protest, Chaining Mechanisms and Policy Outcomes in the Chilean Student Movement (2006-2018) | PArtecipazione e COnflitto | Bidegain, G.; Maillet, A. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1285/i20356609v14i3p1057 | http://siba-ese.unisalento.it/index.php/paco/article/view/24483/20313 | 1057-1075 | Vol: 14 Issue: 3 | 1972-7623 | Thomson Reuters ISI (ESCI) | English | The literature on social movements' policy outcomes agrees on the need for an intertemporal perspective that goes beyond a short-term action-reaction logic to account for the effects of mobilization on policies. However, little attention has been given to the causal mechanisms that link different waves of mobilization with related policy outcomes over time. To do so, we propose the concept of chaining mechanisms as a means to connect different iterations of protest, electoral cycles and policy responses within a mid-term perspective. We distinguish between two types of chaining mechanisms, strategic and inertial, and apply this conceptual framework to the Chilean student movement in the 2006 and 2018 period. We assert that its success in chaining different waves of protest is a crucial factor in accounting for the recent major education reform that took place under Bachelet's government (2014-2018). Beyond the case, the concept contributes to the understanding of the complex interactions between social mobilization and public policy. | |
| Governing sustainability or sustainable governance? Semantic constellations on the sustainability-governance intersection in academic literature | Journal of Cleaner Production | Billi, M.; Mascareño, A.; Edwards, J. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.jclepro.2020.123523 | https://linkinghub.elsevier.com/retrieve/pii/S095965262033568X | 123523 | Vol: 279 | 0959-6526 | Thomson Reuters ISI (SCIE) | English | The concepts of sustainability and governance share an implicit relationship: sustainability has often been asserted to require suitable governance arrangements, which should, in turn, be sustainable. However, this semantic intersection requires more study. To contribute to this gap, this paper aims at: 1) identifying the meanings and interests that are mobilized when the two terms of sustainability and governance intersect within academic communication; and 2) observe semantic structures allowing for the sustainability-governance intersection to translate meanings between different academic communities. To pursue this aim, the study employed a computer-aided algorithm, called Latent Dirichlet Analysis, to produce and examine a topic model of 7.358 Web of Science-indexed papers published between 1992 and 2017. The analysis output 29 topics condensing key themes, concepts, and approaches in academic literature associating sustainability and governance. These were subsequently grouped into four semantic constellations of transversal meanings providing coherence to the heterogeneity of the field: a) governance of State-level sustainable development; b) governance of the sustainable use of natural resources; c) sustainable governance of integration and autonomy in a globalized world; and d) sustainable corporate governance. These results led to the conclusion that the growingly differentiated literature on sustainability and governance has tended to organize in a tightly-knit field, articulating distinct methodological and theoretical perspectives within a shared set of value commitments -the promotion of a sustainable future. Arguably, this has been made possible by the ‘hybrid’ character of the concept of sustainability, as much a description of the world as it is as a prescription of the world-to-be. Additionally, the study unveiled that the implicit relationship linking sustainability and governance has been running both ways, i.e. that governance may be framed as a way to achieve sustainability as much as sustainability can be depicted as a way to achieve governance. | |
| Informe a las Naciones: Gobernanza Climática de los Elementos. Hacia una gobernanza climática del agua, el aire, el fuego y la tierra en Chile, integrada, anticipatoria, socio-ecosistémica y fundada en evidencia. | Billi, M.; Moraga, P.; Aliste, E, E.; Maillet, A.; O'Ryan, R.; Sapiains A., R.; Bórquez, R.; Aldunce, P.; Azócar, G.; Blanco, G.; Carrasco, N.; Galleguillos, M.; Hervé, D.; Ibarra, C.; Gallardo, L.; Inostroza, V.; Lambert, F.; Manuschevic, D.; Martínez, F.; Osses, M.; Rivas, N.; Rojas, M.; Seguel, R... | 2021 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://bit.ly/3JdvVbd | 69 | cr2.cl | La humanidad se ha vuelto una de las mayores fuerzas transformadoras del planeta, generando cambios significativos (y en ocasiones irreversibles) en los equilibrios geofísicos y ecológicos, con consecuencias potencialmente catastróficas y en parte aún desconocidas (Foster et al., 2017; Rockström et al., 2009; Steffen et al., 2007). Entre todas estas alteraciones, el cambio climático adquiere una importancia preponderante debido a la magnitud y escala de sus posibles consecuencias, así como por la complejidad y las controversias que ha caracterizado los intentos de hacerle frente (de Coninck et al., 2018; IPCC, 2018). Contemplar este escenario implica un doble dilema. Por un lado, supone la necesidad de acciones urgentes, concertadas y transformativas, en múltiples escalas y dominios, que lleven a hacerse cargo de los forzantes que causan el cambio climático, sus efectos significativos y desiguales en distintos territorios y poblaciones. Por el otro, se enfrenta a la insuficiencia, parcialidad y limitación demostrada por los modelos tradicionales de gobernanza para enfrentar estos desafíos. |
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| Report to the Nations Climate Governance of the Elements. Towards an Integrated, anticipatory, socio- ecosystemic and evidence- based climate governance of water, air, fire and land. | Billi, M.; Moraga, P.; Aliste, E, E.; Maillet, A.; O'Ryan, R.; Sapiains A., R.; Bórquez, R.; Aldunce, P.; Azócar, G.; Blanco, G.; Carrasco, N.; Galleguillos, M.; Hervé, D.; Ibarra, C.; Gallardo, L.; Inostroza, V.; Lambert, F.; Manuschevic, D.; Martínez, F.; Osses, M.; Rivas, N.; Rojas, M.; Seguel, R... | 2021 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://bit.ly/3JdvVbd | 69 | Humanity has become one of the greatest transformative forces of the planet, generating significant (and sometimes irreversible) changes in geophysical and ecological balances with potentially catastrophic and partly still unknown consequences (Foster et al., 2017; Rockström et al., 2009; Steffen et al, 2007). Among all these alterations, climate change possesses predominant importance due to the magnitude and scale of its potential consequences, as well as the complexity and the controversies that have characterized the attempts to address it (Coninck et al, 2018; IPCC, 2018). Contemplating this scenario entails a double dilemma. On one hand, it implies the need for urgent, coordinated and transformative actions on multiple scales and domains that address the drivers that cause climate change, as well as its significant and unequal effects on different territories and populations. On the other, it faces the insufficiency, biases and limitations shown by traditional governance models in dealing with these challenges. |
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| Boletín especial N° 1 | Cambio climático y nueva Constitución | Billi, M.; Moraga, P.; Bórquez, R.; Azócar, G.; Cordero, L.; Ibarra, C.; Maillet, A.; Martínez, F.; O'Ryan, R.; Pulgar, A.; Rojas, M.; Sapiains, R. | 2021 | https://www.cr2.cl/cambio-climatico-y-nueva-constitucion/ | 7 | Este documento se basa en: Billi, M., Moraga, P., Aliste, E., Maillet, A., O’Ryan, R., Sapiains, R., Bórquez, R. et al. (2021). Gobernanza Climática de los Elementos. Hacia una gobernanza climática del agua, el aire, el fuego y la tierra en Chile, integrada, anticipatoria, socio-ecosistémica y fundada en evidencia. Centro de Ciencia del Clima y la Resiliencia (CR)2, (ANID/FONDAP/15110009), 69 pp. Disponible en www.cr2.cl/gobernanza-elementos/ | ||||||||
| Ecologies of Repair: A Post-human Approach to Other-Than-Human Natures | Frontiers in Psychology | Blanco-Wells, G. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.3389/fpsyg.2021.633737 | https://www.frontiersin.org/articles/10.3389/fpsyg.2021.633737/full | 633737 | Vol: 12 | 1664-1078 | Thomson Reuters ISI (SSCI) | All Open Access; Gold Open Access | English | This conceptual paper explores the theoretical possibilities of posthumanism and presents ecologies of repair as a heuristic device to explore the association modes of different entities, which, when confronted with the effects of human-induced destructive events, seek to repair the damage and transform the conditions of coexistence of various life forms. The central idea is that severe socio-environmental crisis caused by an intensification of industrial activity are conducive to observing new sociomaterial configurations and affective dispositions that, through the reorganization of practices of resistance, remediation, and mutual care, are oriented to generating reparative and/or transformative processes from damaged ecologies and communities. Crises constitute true ontological experimentation processes where the presence of other-than-human natures, and of artifacts or devices that participate in reparative actions, become visible. A post-human approach to nature allows us to use languages and methodologies that do not restrict the emergence of assemblages under the assumption of their a priori ontological separation, but rather examine their reparative potential based on the efficacy of situated relationships. Methodologically, transdisciplinarity is relevant, with ethnography and other engaged methods applied over units of observation and experience called socio-geo-ecologies. The relevant attributes of these socio-geo-ecologies, beyond the individual, community, or institutional aspects, are the specific geological characteristics that make possible an entanglement of interdependent relationships between human and non-human agents. The conceptual analysis is illustrated with empirical examples stemming from socio-geo-ecologies researched in Southern Chile. |
| Plagues, past, and futures for the Yagan canoe people of Cape Horn, southern Chile | Maritime Studies | Blanco-Wells, G.; Libuy, M.; Harambour, A.; Rodríguez, K. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1007/s40152-021-00217-2 | http://link.springer.com/10.1007/s40152-021-00217-2 | 101-113 | Vol: 20 Issue: 1 | 1872-7859, 2212-9790 | Thomson Reuters ISI (ESCI) | All Open Access; Bronze Open Access | English | The manner in which the COVID-19 pandemic has affected the indigenous Yagan people of Navarino Island in southern Chile is the topic of this paper. Like other First Nation communities, these nomadic people suffered decimation and disease in successive encounters with Europeans, and then, in the mid-twentieth century, forced sedentarization by the Chilean State. More recently, the Yagan have fought the expansion of salmon aquaculture to the Island. Making use of a sociomaterial approach, we examine how the threat of past and present viruses and diseases, added to the tragic effects of colonization, become part of a broader sociohistorical debate on the right of coastal peoples to their maritories. Paradoxically, our results suggest that COVID-19 has become part of an assemblage of ethnic revitalization, opening possibilities for the Yagan clans to make some of their envisioned futures possible. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature. |
| Estado, medio ambiente y desarrollo: pasado, presente y futuro de la gobernanza ambiental chilena | Revista Anales de la Universidad de Chile | Borquez, R.; Billi, M.; Moraga Sariego, P. | 2021 | 10.5354/0717-8883.2022.66074 | https://anales.uchile.cl/index.php/ANUC/article/view/66074 | Vol: 19 Issue: 7 | 0717-8883 | Latindex | Chile, con su impronta neoliberal plasmada en la Constitución que lo ha regido por cuarenta años, se ha mantenido hasta ahora firmemente ubicado entre los países de la periferia del capitalismo global (Urquiza, Amigo, Billi, Cortés & Labraña, 2019). Esto se ha visto reflejado en una marcada lógica extractivista, una inmadurez institucional y la persistencia de importantes desigualdades sociales que han potenciado los efectos de la degradación ambiental y la sobreexplotación de los recursos naturales (Urquiza, Amigo, Billi, Cortés & Labraña, 2019). Hoy el país se encuentra en un punto de inflexión: mientras se redactan estas páginas en la Convención Constitucional se está escribiendo la hoja de ruta que nos permitirá navegar durante las próximas décadas. El presente artículo busca reflexionar sobre Estado, medio ambiente y desarrollo realizando un análisis crítico del pasado y presente de la gobernanza ambiental chilena con miras de los desafíos futuros que nos impone la crisis social, ambiental y climática. Frente a eso proponemos una aproximación sistémica que deje atrás la gobernanza fragmentada, reactiva, mercadocéntrica, pues se requieren acciones incrementales y transformadoras: una gobernanza climática integrada. | ||||
| Temperature and precipitation projections for the Antarctic Peninsula over the next two decades: contrasting global and regional climate model simulations | Climate Dynamics | Bozkurt, D.; Bromwich, D.; Carrasco, J.; Rondanelli, R. | 2021 | Agua y Extremos; Zonas Costeras | 10.1007/s00382-021-05667-2 | http://link.springer.com/10.1007/s00382-021-05667-2 | 3853-3874 | Vol: 56 Issue: 11-12 | 0930-7575, 1432-0894 | Thomson Reuters ISI (SCIE) | English | This study presents near future (2020–2044) temperature and precipitation changes over the Antarctic Peninsula under the high-emission scenario (RCP8.5). We make use of historical and projected simulations from 19 global climate models (GCMs) participating in Coupled Model Intercomparison Project phase 5 (CMIP5). We compare and contrast GCMs projections with two groups of regional climate model simulations (RCMs): (1) high resolution (15-km) simulations performed with Polar-WRF model forced with bias-corrected NCAR-CESM1 (NC-CORR) over the Antarctic Peninsula, (2) medium resolution (50-km) simulations of KNMI-RACMO21P forced with EC-EARTH (EC) obtained from the CORDEX-Antarctica. A further comparison of historical simulations (1981–2005) with respect to ERA5 reanalysis is also included for circulation patterns and near-surface temperature climatology. In general, both RCM boundary conditions represent well the main circulation patterns of the historical period. Nonetheless, there are important differences in projections such as a notable deepening and weakening of the Amundsen Sea Low in EC and NC-CORR, respectively. Mean annual near-surface temperatures are projected to increase by about 0.5–1.5 ∘C across the entire peninsula. Temperature increase is more substantial in autumn and winter (∼ 2 ∘C). Following opposite circulation pattern changes, both EC and NC-CORR exhibit different warming rates, indicating a possible continuation of natural decadal variability. Although generally showing similar temperature changes, RCM projections show less warming and a smaller increase in melt days in the Larsen Ice Shelf compared to their respective driving fields. Regarding precipitation, there is a broad agreement among the simulations, indicating an increase in mean annual precipitation (∼ 5 to 10%). However, RCMs show some notable differences over the Larsen Ice Shelf where total precipitation decreases (for RACMO) and shows a small increase in rain frequency. We conclude that it seems still difficult to get consistent projections from GCMs for the Antarctic Peninsula as depicted in both RCM boundary conditions. In addition, dominant and common changes from the boundary conditions are largely evident in the RCM simulations. We argue that added value of RCM projections is driven by processes shaped by finer local details and different physics schemes that are introduced by RCMs, particularly over the Larsen Ice Shelf. | |
| Influence of African Atmospheric Rivers on Precipitation and Snowmelt in the Near East's Highlands | Journal of Geophysical Research: Atmospheres | Bozkurt, D.; Sen, O.; Ezber, Y.; Guan, B.; Viale, M.; Caglar, F. | 2021 | Agua y Extremos | 10.1029/2020JD033646 | https://onlinelibrary.wiley.com/doi/10.1029/2020JD033646 | art: e2020JD033646 | Vol: 126 Issue: 4 | 2169-897X | Thomson Reuters ISI (SCIE) | English | Atmospheric rivers (ARs) traveling thousands of kilometers over arid North Africa could interact with the highlands of the Near East (NE), and thus affect the region's hydrometeorology and water resources. Here, we use a state-of-the-art AR tracking database, and reanalysis and observational datasets to investigate the climatology (1979–2017) and influences of these ARs in snowmelt season (March–April). The Red Sea and northeast Africa are found to be the major source regions of these ARs, which are typically associated with the eastern Mediterranean trough positioned over the Balkan Peninsula and a blocking anticyclone over the NE-Caspian region, triggering southwesterly air flow toward the NE's highlands. Approximately 8% of the ARs are relatively strong (integrated water vapor transport>275kg m1 s1). AR days exhibit enhanced precipitation over the crescent-shaped orography of the NE region. Mean AR days indicate wetter (up to+2mm day1) and warmer (up to+1.5°C) conditions than all-day climatology. On AR days, while snowpack tends to decrease (up to 30%) in the Zagros Mountains, it can show decreases or increases in the Taurus Mountains depending largely on elevation. A further analysis with the observations and reanalysis indicates that extreme ARs coinciding with large scale sensible heat transport can significantly increase the daily discharges. These results suggest that ARs can have notable impacts on the hydrometeorology and water resources of the region, particularly of lowland Mesopotamia, a region that is famous with great floods in the ancient narratives. | |
| Projected increases in surface melt and ice loss for the Northern and Southern Patagonian Icefields | Scientific Reports | Bravo, C.; Bozkurt, D.; Ross, A.; Quincey, D. | 2021 | Zonas Costeras | 10.1038/s41598-021-95725-w | https://www.nature.com/articles/s41598-021-95725-w | 16847 | Vol: 11 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Northern Patagonian Icefield (NPI) and the Southern Patagonian Icefield (SPI) have increased their ice mass loss in recent decades. In view of the impacts of glacier shrinkage in Patagonia, an assessment of the potential future surface mass balance (SMB) of the icefields is critical. We seek to provide this assessment by modelling the SMB between 1976 and 2050 for both icefields, using regional climate model data (RegCM4.6) and a range of emission scenarios. For the NPI, reductions between 1.5 m w.e. (RCP2.6) and 1.9 m w.e. (RCP8.5) were estimated in the mean SMB during the period 2005–2050 compared to the historical period (1976–2005). For the SPI, the estimated reductions were between 1.1 m w.e. (RCP2.6) and 1.5 m w.e. (RCP8.5). Recently frontal ablation estimates suggest that mean SMB in the SPI is positively biased by 1.5 m w.e., probably due to accumulation overestimation. If it is assumed that frontal ablation rates of the recent past will continue, ice loss and sea-level rise contribution will increase. The trend towards lower SMB is mostly explained by an increase in surface melt. Positive ice loss feedbacks linked to increasing in meltwater availability are expected for calving glaciers. |
| Escuelas Seguras en tiempos del COVID-19 | Brevis, W.; Cortés, S.; Duarte, I.; Fica, D.; Förster, F.; Martínez, S.; Rojas, M.; Repetto, P.; Rondanelli, R.; Valdés, M. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://portaluchile.uchile.cl/documentos/escuelas-seguras-en-tiempos-del-covid-19_176441_0_4940.pdf | v1.3 | ||||||||
| Past abrupt changes, tipping points and cascading impacts in the Earth system | Nature Geoscience | Brovkin, V.; Brook, E.; Williams, J.; Bathiany, S.; Lenton, T.; Barton, M.; DeConto, R.; Donges, J.; Ganopolski, A.; McManus, J.; Praetorius, S.; de Vernal, A.; Abe-Ouchi, A.; Cheng, H.; Claussen, M.; Crucifix, M.; Gallopín, G.; Iglesias, V.; Kaufman, D.; Kleinen, T.; Lambert, F.; van der Leeuw, S.;... | 2021 | Ciudades Resilientes | 10.1038/s41561-021-00790-5 | https://www.nature.com/articles/s41561-021-00790-5 | 550-558 | Vol: 14 Issue: 8 | 1752-0894, 1752-0908 | Thomson Reuters ISI (SCIE) | English | The geological record shows that abrupt changes in the Earth system can occur on timescales short enough to challenge the capacity of human societies to adapt to environmental pressures. In many cases, abrupt changes arise from slow changes in one component of the Earth system that eventually pass a critical threshold, or tipping point, after which impacts cascade through coupled climate–ecological–social systems. The chance of detecting abrupt changes and tipping points increases with the length of observations. The geological record provides the only long-term information we have on the conditions and processes that can drive physical, ecological and social systems into new states or organizational structures that may be irreversible within human time frames. Here, we use well-documented abrupt changes of the past 30 kyr to illustrate how their impacts cascade through the Earth system. We review useful indicators of upcoming abrupt changes, or early warning signals, and provide a perspective on the contributions of palaeoclimate science to the understanding of abrupt changes in the Earth system. | |
| Energy and Water Policies in Chile, Two Different Endings with Implications in the Water-Energy Nexus | Energies | Bórquez, R.; Fuster, R. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.3390/en14113286 | https://www.mdpi.com/1996-1073/14/11/3286 | 3286 | Vol: 14 Issue: 11 | 1996-1073 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Energy and water have faced important levels of conflicts in the last 20–25 years in Chile. However, the way that they have been politically addressed in the last decade differs. These differences emerge from how these fields have been historically configurated, impacting on how the policy problems and policy options have been framed. Using thematic analysis of 93 interviews and documentary analysis, this article analyzes by contrasting two participatory processes which nourish the formulation of the energy and water policies in Chile in 2014–2015. It seeks to understand the factors that may influence why the development, impact and inclusion of new voices in public policies related to water and energy have been different, and how that can impact the water–energy nexus. Five factors emerge as determinants in this difference: structure of use, number of actors, governance and institutional framework, elite conformation, and legal framework. These factors impacted the policy processes and the scope of the policy outcomes, generating two different results: a long-term energy policy, and a water policy that did not survive the presidential period. Thus, the water–energy nexus is under pressure as a result of the tension between power structures, social responses to environmental issues and decision-making, environmental limitations, and climate change stressors, creating greater vulnerability and conflicts. |
| Northern Chile intermediate-depth earthquakes controlled by plate hydration | Geophysical Journal International | Cabrera, L.; Ruiz, S.; Poli, P.; Contreras-Reyes, E.; Osses, A.; Mancini, R. | 2021 | Ciudades Resilientes | 10.1093/gji/ggaa565 | https://academic.oup.com/gji/article/226/1/78/5998227 | 78-90 | Vol: 226 Issue: 1 | 0956-540X, 1365-246X | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | SUMMARY We investigate the variations of the seismic source properties and aftershock activity using kinematic inversions and template-matching for six large magnitude intermediate-depth earthquakes occurred in northern Chile. Results show similar rupture geometry and stress drop values between 7 and 30 MPa. Conversely, aftershock productivity systematically decreases for the deeper events within the slab. Particularly, there is a dramatic decrease in aftershock activity below the 400–450 °C isotherm depth, which separates high- and low-hydrated zones. The events exhibit tensional focal mechanisms at unexpected depths within the slab, suggesting a deepening of the neutral plane, where the extensional regimen reaches the 700–800 °C isotherm depth. We interpret the reduction of aftershocks in the lower part of the extensional regime as the absence of a hydrated-slab at those depths. Our finding highlights the role of the thermal structure and fluids in the subducting plate in controlling the intermediated-depth seismic activity and shed new light in their causative mechanism. |
| Desarrollo de indicadores de pobreza energética en América Latina y el Caribe | Recursos naturales y desarrollo, Comisión Económica para América Latina y el Caribe (CEPAL) | Calvo, R.; Alamos, N.; Billi, M.; Urquiza, A.; Contreras Lisperguer, R. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://www.cepal.org/es/publicaciones/47216-desarrollo-indicadores-pobreza-energetica-america-latina-caribe | 1-88 | Vol: Santiago, Comisión Económica para América Latina y el Caribe (CEPAL) Issue: 207 | 2664-4541 | Spanish | Garantizar el acceso a una energía asequible, segura y sostenible para todos y todas es un pilar fundamentalde los objetivos de desarrollo sostenible, siendo uno de los elementos base para la satisfacción de una gran variedad de necesidades humanas, el desarrollo económico y humano. Sin embargo, estudios recientes en América Latina y el Caribe han evidenciado las condiciones de acceso desigual a servicios energéticos de calidad en la región, documentando la exposición de una proporción relevante de la población a diversas barreras en el acceso a energía: falta de electrificación, uso de combustibles contaminantes, nula o deficiente aislación térmica de las viviendas, alto gasto en servicios energéticos, entre otras. En este marco, el Observatorio Regional de Energías Sostenibles (ROSE) de la CEPAL, está realizando esfuerzos para poder cuantificar en la región la pobreza energética. Este informe complementa el reporte anterior publicado por la CEPAL, “Seguridad hídrica y energética en América Latina y el Caribe: definición y aproximación territorial para el análisis de brechas y riesgos de la población”, en dos aspectos. En primer lugar, se busca aportar en el debate de política pública sobre pobreza energética en América Latina y el Caribe, en base a la propuesta conceptual que define a la pobreza energética como un fenómeno multidimensional y situado desde una perspectiva territorial introducida por la CEPAL, facilitando una mejor integración de los conceptos de seguridad y transición que permita una perspectiva integral de los desafíos en materia de energía de los países de la región. Y, en segundo lugar, profundiza el trabajo realizado por la CEPAL ampliando la mirada de la pobreza energética más allá de la electrificación, evidenciando, a través de diversos indicadores, las múltiples formas de privación del acceso equitativo a energía de calidad y los diversos impactos que esto tiene en los hogares que la enfrentan. |
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| Territorial Energy Vulnerability Assessment to Enhance Just Energy Transition of Cities | Frontiers in Sustainable Cities | Calvo, R.; Amigo, C.; Billi, M.; Fleischmann, M.; Urquiza, A.; Álamos, N.; Navea, J. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.3389/frsc.2021.635976 | https://www.frontiersin.org/articles/10.3389/frsc.2021.635976/full | 635976 | Vol: 3 | 2624-9634 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | Energy poverty is a crucial concept in current global energy policy, both for the importance of securing equitable access to high-quality energy services to all human populations and to advance toward a just energy transition to a decarbonized economy. Nonetheless, one of the limitations of this concept due to its focus at the household scale, it has tended to omit relevant energy conditions at a territorial scale, which can also be a dimension of significant deprivation (e.g., transportation, schools, hospitals, public services, industrial uses among others.). On the other hand, energy services are highly dependent on context: on the geographic, ecological, technical, economic, and sociocultural conditions. This context-dependency determines the range of energy and technological alternatives available in a territory. Hence, a conceptual framework is required to better understand the starting point to a just energy transition, capable of integrating the complexity of socio-techno-ecological systems. To fill this gap, we present a framework based on the concept of Territorial Energy Vulnerability (TEV), defined as the propensity of a territory to not guarantee equitable access—in quantity and quality—to resilient energy services that allow the sustainable human and economic development of its population. That is a greater probability of inequity in access to energy services or a significant impacts derived from socio-natural risks that make it incapable of guaranteeing a sustainable and resilient provision of these services. Built on state-of-the-art conceptualizations of risk, we develop an indicator-based framework on vulnerability understood as the combination of sensitivity and resilience characteristics of socio-techno-ecological systems. Sensitivity relates to economic, demographic, infrastructure, technology, culture, and knowledge characteristics of socio-techno-ecological components. Meanwhile, resilience is presented in a three-dimensional framework based on flexibility, register, and self-transformation capacity of socio-techno-ecological systems. An application of this framework is developed using three case studies: Arica, Los Andes and Coyhaique, all Chilean cities with diverse ecological, technical, economic, and sociocultural conditions that shape territorial vulnerability. Using this framework as a diagnostic tool, the development of a just energy transition could adapt existing concepts of energy poverty and decarbonization pathways into context-specific guidelines and policies. |
| Observatorio de Nieve en los Andes de Argentina y Chile. Instituto Argentino de Nivología, Glaciología, y Ciencias Ambientales (IANIGLA-CONICET). Centro de Ciencia del Clima y la Resiliencia (CR)². | Cara, L.; Masiokas, M.; Villalba, R.; Garreaud, R.; Christie, D. | 2021 | Agua y Extremos | 10.13140/RG.2.2.11321.70245 | http://rgdoi.net/10.13140/RG.2.2.11321.70245 | Spanish | |||||||
| Exploring the multidimensional effects of human activity and land cover on fire occurrence for territorial planning | Journal of Environmental Management | Carrasco, J.; Acuna, M.; Miranda, A.; Alfaro, G.; Pais, C.; Weintraub, A. | 2021 | Cambio de Uso de Suelo | 10.1016/j.jenvman.2021.113428 | https://linkinghub.elsevier.com/retrieve/pii/S0301479721014900 | 113428 | Vol: 297 | 03014797 | Thomson Reuters ISI (SCIE) | English | The strong link between climate change and increased wildfire risk suggests a paradigm change on how humans must co-exist with fire and the environment. Different studies have demonstrated that human-induced fire ignitions can account for more than 90 % of forest fires, so human co-existence with wildfires requires informed decision making via preventive policies in order to minimize risk and adapt to new conditions. In this paper, we address the multidimensional effects of three groups of drivers (human activity, geographic and topographic, and land cover) that can be managed to assist in territorial planning under fire risk. We found critical factors of strong interactions with the potential to increase the likelihood of starting a fire. Our solution approach included the application of a Machine Learning method called Random Undersampling and Boosting (RUSBoost) to assess risk (fire occurrence probability), which was subsequently accompanied by a sensitivity analysis that revealed interactions of various levels of risk. The prediction performance of the proposed model was assessed using several statistical measures such as the Receiver Operating Characteristic curve (ROC) and the Area Under the Curve (AUC). The results confirmed the high accuracy of our model, with an AUC of 0.967 and an overall accuracy over test data of 93.01 % after applying a Bayesian approach for hyper-parameter optimization. The study area to test our solution approach comprised the entire geographical territory of central Chile. | |
| A review of the observed air temperature in the Antarctic Peninsula. Did the warming trend come back after the early 21st hiatus? | Polar Science | Carrasco, J.; Bozkurt, D.; Cordero, R. | 2021 | Zonas Costeras | 10.1016/j.polar.2021.100653 | https://linkinghub.elsevier.com/retrieve/pii/S1873965221000189 | 100653 | Vol: 28 | 18739652 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Recent changes in the near-surface air temperature (nSAT) in the Antarctic Peninsula (AP) suggests that the absence of 21st century warming on Antarctic Peninsula may be coming to end. To examine this, the long-term annual and seasonal variability of the nSAT at eight Antarctic stations located in the AP are analyzed using available data from the SCAR Reader database, complemented with data from the Chilean Weather Service (Frei and O’Higgins). An exponential lter was applied to the original annual and seasonal mean series to obtain a decadal-like variation of the nSAT. A stacked and the standardized anomaly of the nSAT record was constructed to examine the average regional behavior in the AP. Cumulative sum (CUSUM) and changepoint analysis were applied through the stacked nSAT series to highlight signi cant changes caused by variation in weather and climate. The CUSUM and bootstrapping analysis revealed two statistically signi cant breaking points during the 1978–2020 period. The rst one occurred in the late nineties ending a warming period and making the beginning of a cooling period; the second one may have taken place in the mid-2010s and could mark the end of the warming pause. These trends appear to be consistent with the changes observed in the large-scale climate modes (i.e., the Antarctic Annular Mode – AAO). |
| Embedding effect and the consequences of advanced disclosure: evidence from the valuation of cultural goods | Empirical Economics | Carrasco, M.; Vasquez-Lavin, F.; Ponce Oliva, R.; Bustamante Oporto, J.; Barrientos, M.; Cerda, A. | 2021 | Cambio de Uso de Suelo | 10.1007/s00181-020-01897-1 | http://link.springer.com/10.1007/s00181-020-01897-1 | 1039-1062 | Vol: 61 Issue: 2 | 0377-7332, 1435-8921 | Thomson Reuters ISI (SSCI) | English | This study revisits the embedding effect, a long-standing problem in the nonmarket valuation literature. The embedding effect was a popular research topic during the 1990s, especially following the Exxon Valdez oil spill in Alaska. It has resurfaced after a special issue of The Journal of Economic Perspectives in 2012 in which Jerry Hausmann asserts that among the three long-standing problems with contingent valuation, the embedding effect is the most challenging. In this study, we focus on how information disclosure regarding the nested structure of goods affects both the willingness to pay and the presence of the embedding effect. Our results suggest that the level of embedding can be reduced with a more complete description of the nested structure of the goods under valuation. Therefore, it is highly important for each valuation study to test whether sufficient information is provided on the goods’ nested structure to ensure that the relationships among the goods’ subsets are correctly understood by respondents. We show that by providing respondents with more high-quality information, it is possible to mitigate the embedding effect. | |
| Estimating the implicit discount rate for new technology adoption of wood-burning stoves | Energy Policy | Carrasco-Garcés, M.; Vásquez-Lavín, F.; Ponce Oliva, R.; Diaz Pincheira, F.; Barrientos, M. | 2021 | Cambio de Uso de Suelo | 10.1016/j.enpol.2021.112407 | https://linkinghub.elsevier.com/retrieve/pii/S0301421521002779 | 112407 | Vol: 156 | 03014215 | Thomson Reuters ISI (SCIE; SSCI) | English | In the last decade, there have been several initiatives to incentivize Efficient Energy Technologies (EET) to reduce air pollution caused by wood-burning in developing countries. More efficient woodstoves can improve health, reduce family expenditures, CO2 emissions, and forest degradation. Despite these benefits, there is low level of adoption of EETs. This paper contributed to the literature in three ways. First, it estimates the implicit discount rate (IDR) used by individuals to decide whether to adopt EET using exponential and hyperbolic specifications. Second, it includes sociodemographic characteristics in the definition of the IDR. Third, it evaluates how the adoption curve changes by different policy designs. Since the interest rate is part of the policy design, comparing the interest rate and the IDR is relevant to increasing adoption. Our monthly estimated IDR is between 1.7% and 5.4% with a significant overlap with market interest rate. The IDR is affected by the perception of the future economic situation, trust in environmental authorities, happiness, and gender. We found that using an interest rate lower than the IDR increases the probability of adoption significantly. An understanding of the effects of copayments, payment frequencies, and difference between interest rates and IDR is needed to maximize adoption. | |
| Extreme sea levels at Rapa Nui (Easter Island) during intense atmospheric rivers | Natural Hazards | Carvajal, M.; Winckler, P.; Garreaud, R.; Igualt, F.; Contreras-López, M.; Averil, P.; Cisternas, M.; Gubler, A.; Breuer, W. | 2021 | Agua y Extremos | 10.1007/s11069-020-04462-2 | http://link.springer.com/10.1007/s11069-020-04462-2 | 1619-1637 | Vol: 106 Issue: 2 | 0921-030X, 1573-0840 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | In addition to the tsunami hazard posed by distant great earthquakes, Rapa Nui (Easter Island), in the Southeast Pacific Ocean, is exposed to frequent and intense coastal storms. Here, we use sea-level records and field surveys guided by video and photographic footage to show that extreme sea levels at Rapa Nui occur much more frequent than previously thought and thus constitute an unrecognized hazard to the inland’s maritime supply chain. We found that extreme sea-level events, including the two most extreme (March 5th and May 5th, 2020) in our 17-month-long analyzed period (from January 1st, 2019, to May 31st, 2020), resulted from constructive superpositions of seiches on the shelf, storm surges and high tides. By further analyzing time series of atmospheric and wind-generated wave data, we conclude that these extreme sea levels are ultimately driven by the breaking of large waves near the coastline (i.e., wave setup), with lesser contribution of barometric setup and even less of wind setup. We also propose that these large waves were mainly generated from strong, long-lasting, NW winds associated with intense atmospheric rivers (long, narrow regions in the atmosphere that transport abundant water vapor) passing over Rapa Nui. Given that the intensity of atmospheric rivers and sea level are thought to increase as climate changes, a deeper understanding of the relation between meteorological and oceanographic processes at Rapa Nui is strongly needed. |
| Dissolved nitrous oxide distribution in the central South Pacific | Charpentier, J.; Farías, L.; Pizarro, O. | 2021 | Zonas Costeras | 10.1594/PANGAEA.928664 | https://doi.pangaea.de/10.1594/PANGAEA.928664 | Pangaea | English | Nitrous oxide (N2O) is an important atmospheric trace gas involved in tropospheric warming and stratospheric ozone depletion. The ocean is a net source of this gas, contributing around 25% of global N2O sources, although this emission is highly variable. It is the case of eastern South Pacific, a region with marked zonal gradients, ranging from highly productive and suboxic conditions in coastal upwelling systems to oligotrophic and oxygenated conditions in the subtropical gyre. Indeed, South Pacific Ocean has the largest permanent anticyclonic oceanic gyre which has been described as the most oligotrophic zone in the world ocean. Nitrous oxide concentration in the water column was measured on a transect crossing the Subtropical South Pacific Gyre during the BIOSOPE cruise (austral spring, 2004). This dataset includes nitrous oxide and nutrient concentrations at different depths from French program BIOSOPE, funded by the Centre National de la Recherche Scientifique (CNRS), the Institut des Sciences de l'Univers (INSU), the Centre National d'Etudes Spatiales (CNES), the European Space Agency (ESA), The National Aeronautics and Space Administration (NASA) and the Natural Sciences and Engineering Research Council of Canada (NSERC). Nitrous oxide measurements belong to Concepción University. | |||||
| Effect of urban tree diversity and condition on surface temperature at the city block scale | Urban Forestry & Urban Greening | Chinchilla, J.; Carbonnel, A.; Galleguillos, M. | 2021 | Cambio de Uso de Suelo | 10.1016/j.ufug.2021.127069 | https://linkinghub.elsevier.com/retrieve/pii/S1618866721000947 | 127069 | Vol: 60 | 16188667 | Thomson Reuters ISI (SCIE; SSCI) | English | Urban forests affect land surface temperature (LST) within a city due to the cooling effect of transpiration. The latter depends on tree health, but it can also be affected by the structure and composition of forest, as a mono-species environment may potentially worsen the health of urban forest. The following hypotheses are therefore proposed: a) greater tree diversity within urban forest results in lower LST at the city block scale; and b) the state of biotic disturbance of urban forest is negatively correlated with LST. The present research explores the relationship between urban forest tree diversity and health based on a survey of 38,950 individuals in the district of Providencia in the city of Santiago, Chile, and compares this information against LST data from the ASTER satellite instrument at the city block scale. The health of the urban forest was determined by expert knowledge means of a field survey that collected data concerning growth stage, phytosanitary state, and state of biotic disturbance. The first hypothesis could not be tested by the lack of urban tree diversity which showed strong domination of three species with more than 52 % of abundance (Robinia pseudoacacia, Platanus orientalis and Acer negundo). The second hypothesis was proved since the results revealed a positive and significant correlation between urban forest diversity and LST, with a Spearman's correlation coefficient of between 0.56 and 0.7. A positive and significant correlation of 0.55 was found between mean biotic disturbance (BDSm) and median LST (Med), indicating a direct relationship between higher LST and poorer urban forest health. A possible explanation is that, among the trees surveyed within the urban forest, the effect of biotic disturbance is greater than that of species diversity. As such, it may be concluded that planting of trees on city streets as a means of temperature moderation is made less effective if specimens are maintained in a poor general condition of health. | |
| Proteorhodopsin Phototrophy in Antarctic Coastal Waters | mSphere | Cifuentes-Anticevic, J.; Alcamán-Arias, M.; Alarcón-Schumacher, T.; Tamayo-Leiva, J.; Pedrós-Alió, C.; Farías, L.; Díez, B. | 2021 | Zonas Costeras | 10.1128/mSphere.00525-21 | https://journals.asm.org/doi/10.1128/mSphere.00525-21 | 1-17 | Vol: 6 Issue: 4 | 2379-5042 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Proteorhodopsin-bearing microorganisms in the Southern Ocean have been overlooked since their discovery in 2000. The present study identify taxonomy and quantify the relative abundance of proteorhodopsin-bearing bacteria and proteorhodopsin gene transcription in the West Antarctic Peninsula’s coastal waters. , ABSTRACT Microbial proton-pumping rhodopsins are considered the simplest strategy among phototrophs to conserve energy from light. Proteorhodopsins are the most studied rhodopsins thus far because of their ubiquitous presence in the ocean, except in Antarctica, where they remain understudied. We analyzed proteorhodopsin abundance and transcriptional activity in the Western Antarctic coastal seawaters. Combining quantitative PCR (qPCR) and metagenomics, the relative abundance of proteorhodopsin-bearing bacteria accounted on average for 17, 3.5, and 29.7% of the bacterial community in Chile Bay (South Shetland Islands) during 2014, 2016, and 2017 summer-autumn, respectively. The abundance of proteorhodopsin-bearing bacteria changed in relation to environmental conditions such as chlorophyll a and temperature. Alphaproteobacteria , Gammaproteobacteria , and Flavobacteriia were the main bacteria that transcribed the proteorhodopsin gene during day and night. Although green light-absorbing proteorhodopsin genes were more abundant than blue-absorbing ones, the latter were transcribed more intensely, resulting in >50% of the proteorhodopsin transcripts during the day and night. Flavobacteriia were the most abundant proteorhodopsin-bearing bacteria in the metagenomes; however, Alphaproteobacteria and Gammaproteobacteria were more represented in the metatranscriptomes, with qPCR quantification suggesting the dominance of the active SAR11 clade. Our results show that proteorhodopsin-bearing bacteria are prevalent in Antarctic coastal waters in late austral summer and early autumn, and their ecological relevance needs to be elucidated to better understand how sunlight energy is used in this marine ecosystem. IMPORTANCE Proteorhodopsin-bearing microorganisms in the Southern Ocean have been overlooked since their discovery in 2000. The present study identify taxonomy and quantify the relative abundance of proteorhodopsin-bearing bacteria and proteorhodopsin gene transcription in the West Antarctic Peninsula’s coastal waters. This information is crucial to understand better how sunlight enters this marine environment through alternative ways unrelated to chlorophyll-based strategies. The relative abundance of proteorhodopsin-bearing bacteria seems to be related to environmental parameters (e.g., chlorophyll a , temperature) that change yearly at the coastal water of the West Antarctic Peninsula during the austral late summers and early autumns. Proteorhodopsin-bearing bacteria from Antarctic coastal waters are potentially able to exploit both the green and blue spectrum of sunlight and are a prevalent group during the summer in this polar environment. |
| La participación ciudadana en los planes de descontaminación atmosférica. Una evaluación sin romance | Revista de Derecho Ambiental | Cordero, L.; Insunza, X. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.5354/0719-4633.2021.58361 | https://revistaderechoambiental.uchile.cl/index.php/RDA/article/view/58361 | 77 | Vol: 15 | 0719-4633, 0718-0101 | Scopus | English | Este es un trabajo exploratorio que tiene por finalidad analizar la participación ciudadana como mecanismo de incidencia en la definición de actos administrativos o políticas públicas. Para ello, se estudia el proceso de elaboración de los planes de prevención y/o descontaminación como instrumentos que manifiestan un problema global en un territorio donde resulta indispensable la adopción de medidas y en que la incidencia de la participación debería ser gravitante y efectiva. Con tal finalidad, se expone el marco regulatorio nacional, el proceso de elaboración de los planes y los resultados de la participación, demostrando que no existe consistencia entre lo normativamente pretendido y la implementación de los procedimientos participativos. | |
| Evaluation of multiple indices of the South American monsoon | International Journal of Climatology | Correa, I.; Arias, P.; Rojas, M. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1002/joc.6880 | https://onlinelibrary.wiley.com/doi/10.1002/joc.6880 | joc.6880 | Vol: 41 Issue: s1 | 0899-8418, 1097-0088 | Thomson Reuters ISI (SCIE) | English | In this article, multiple methods for estimating the onset and demise of the South American Monsoon System (SAMS) are evaluated during the period 1979–2018. The results obtained from indices based on precipitation, outgoing longwave radiation and combined empirical orthogonal functions (LISAM) show a delay in the SAMS onset while the demise dates do not show marked changes during the considered period. The latter indicates that the observed shortening of the SAMS (and the consistent lengthening of the southern Amazon dry season) mainly depend on variations at the onset stage of the SAMS, as identified in previous studies based on different databases and methodologies. This result is independent on the observational dataset considered. This allows resolving previously inconsistent results on the shortening of the SAMS. Furthermore, the climatological patterns of precipitation and atmospheric circulation at surface and upper levels associated with SAMS are best represented by the precipitation‐based index; however, all indices exhibit general difficulties in representing the evolution of the atmospheric circulation at 200 hPa. Finally, our analyses suggest that including northeastern (NE) Brazil in the domain considered to characterize the SAMS tends to alter the estimates of SAMS timing, primarily its onset. In particular, the trend towards late onsets of the SAMS is evidenced by all indices over spatial domains that do not include NE Brazil, while this trend is considerably weakened or not significant when this area is included. This denotes a strong sensitivity of the different indices to the spatial domain considered for SAMS characterization. | |
| Present‐Day Patagonian Dust Emissions: Combining Surface Visibility, Mass Flux, and Reanalysis Data | Journal of Geophysical Research: Atmospheres | Cosentino, N.; Gaiero, D.; Lambert, F. | 2021 | Ciudades Resilientes | 10.1029/2020JD034459 | https://onlinelibrary.wiley.com/doi/10.1029/2020JD034459 | art: e2020JD034459 | Vol: 126 Issue: 16 | 2169-897X | Thomson Reuters ISI (SCIE) | English | The magnitude of the climatic forcing associated with mineral dust aerosols remains uncertain due in part to a lack of observations on dust sources. While modeling and satellite studies provide spatially extensive constraints, they must be supported by surface-validating dust monitoring. Southern South America is the main dust source to the southern oceans (>45°S), a region of low biological productivity potentially susceptible to increased micronutrient fertilization through dust deposition, as well as one of the main dust sources to Antarctica, implying long-range transport of dust from Patagonia and potentially affecting snow cover albedo. We present multiyear time series of dust-related visibility reduction (DRVR) and dust mass flux in Patagonia. We find that local DRVR is partly controlled by long-term (i.e., months) water deficit, while same-day conditions play a smaller role, reflective of water retention properties of fine-grained dust-emitting soils in low-moisture conditions. This is supported independently by reanalysis data showing that large-scale dust outbreaks are usually associated with anomalously high long-term water deficit. By combining visibility data, surface dust sampling, and particle dispersion modeling, we derive regional dust emission rates. Our results suggest that the inclusion of long-term soil hydrologic balance parameterizations under low-moisture conditions may improve the performance of dust emission schemes in Earth system models. | |
| Assessment of Cardiovascular Risk in Women with Periodontal Diseases According to C-reactive Protein Levels | Biomolecules | Da Venezia, C.; Hussein, N.; Hernández, M.; Contreras, J.; Morales, A.; Valdés, M.; Rojas, F.; Matamala, L.; Hernández-Ríos, P. | 2021 | Ciudades Resilientes | 10.3390/biom11081238 | https://www.mdpi.com/2218-273X/11/8/1238 | 1238 | Vol: 11 Issue: 8 | 2218-273X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Cardiovascular diseases (CVD) are highly prevalent non-communicable diseases worldwide. Periodontitis may act as a non-traditional cardiovascular risk (CVR) factor, linked by a low-grade systemic inflammation mediated by C-reactive protein (CRP). Patients with periodontitis reported higher serum CRP levels; however, a CRP systemic and periodontal correlation in gingival crevicular fluid (GCF) and its CVR impact have been barely studied. We aimed to assess the association between periodontal diseases and CVR in a group of adult women, based on serum high-sensitivity CRP (hs-CRP) levels; and secondly, to determine the association between serum and GCF CRP levels. Gingival crevicular fluid and blood samples were obtained from women with periodontitis, gingivitis, and healthy controls. Serum and GCF CRP were determined by turbidimetric method and Luminex technology, respectively. Data were analyzed and adjusted by CVR factors. All women presented moderate CVR, without an evident association between serum hs-CRP levels and periodontal diseases. While serum hs-CRP concentrations did not significantly differ between groups, patients with gingivitis and periodontitis showed higher CRP levels in GCF, which positively correlated to CRP detection in serum. |
| More Money, More Problems: Quality Assurance in Higher Education in Chile (2006–2018) | Bulletin of Latin American Research | Davila, M.; Maillet, A. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1111/blar.13190 | https://onlinelibrary.wiley.com/doi/10.1111/blar.13190 | 534-548 | Vol: 40 Issue: 4 | 0261-3050, 1470-9856 | Thomson Reuters ISI (SSCI) | English | Since the radical neoliberal reforms to Chilean higher education of the 1980s, the creation of a quality regulatory system has been gradual and unfinished. It was only in 2006 that a law created the National Commission for Accreditation and two instruments: programmes and institutions accreditation. This article analyses the design and implementation of the latter policy instrument using mixed methods, including in-depth interviews with key actors. Our findings show that, although regulations have introduced quality assurance as a key element in higher education policy, the link established between accreditation and financing has generated incentives that dangerously weaken these quality mechanisms. | |
| Electrochemical enrichment of marine denitrifying bacteria to enhance nitrate metabolization in seawater | Journal of Environmental Chemical Engineering | De La Fuente, M.; De la Iglesia, R.; Farías, L.; Daims, H.; Lukumbuzya, M.; Vargas, I. | 2021 | Zonas Costeras | 10.1016/j.jece.2021.105604 | https://linkinghub.elsevier.com/retrieve/pii/S2213343721005819 | 105604 | Vol: 9 Issue: 4 | 2213-3437 | Thomson Reuters ISI (SCIE) | English | High concentrations of nitrate from industrial discharges to coastal marine environments are a matter of concern owing to their ecological consequences. In the last years, Bioelectrochemical Denitrification Systems (BEDS) have emerged as a promising nitrate removal technology. However, they still have limitations, such as the enrichment strategy for specific microbial communities in the electrodes under natural conditions. In this study, three-electrode electrochemical cells were used to test microbial enrichment from natural seawater by applying three reported potentials associated with the dissimilatory denitrification process (−130, −260, and −570 mV vs. Ag/AgCl). The microbial community analysis showed that by applying −260 mV (vs. Ag/AgCl) to the working electrode, it was possible to significantly enrich denitrifying microorganisms, specifically Marinobacter, in comparison with the control. Furthermore, −260 mV (vs. Ag/AgCl) led to a significantly higher nitrate removal than other conditions, which, combined with cyclic voltammetry analysis, suggested that the polarized electrodes worked as external electron donors for nitrate reduction. Hence, this work demonstrates for the first time that it is possible to enrich marine denitrifying microorganisms by applying an overpotential of −260 mV (vs. Ag/AgCl) without the need for a culture medium, the addition of an exogenous electron donor (i.e., organic matter) or a previously enriched inoculum. | |
| Identifying key driving mechanisms of heat waves in central Chile | Climate Dynamics | Demortier, A.; Bozkurt, D.; Jacques-Coper, M. | 2021 | Agua y Extremos; Zonas Costeras | 10.1007/s00382-021-05810-z | https://link.springer.com/10.1007/s00382-021-05810-z | 2415-2432 | Vol: 57 Issue: 9-10 | 0930-7575, 1432-0894 | Thomson Reuters ISI (SCIE) | English | This study explores the main drivers of heat wave (HW) events in central Chile using state-of-the-art reanalysis data (ERA5) and observations during the extended austral summer season (November to March) for the period 1979–2018. Frequency and intensity aspects of the HW events are considered using the total number of the HW events per season and the amplitude. We first contrast ERA5 with several surface meteorological stations in central Chile to evaluate its ability to capture daily maximum temperature variability and the HW events. We then use synoptic- and large-scale fields and teleconnection patterns to address the most favorable conditions of the HW events from a climatological perspective as well as from the extreme January 2017 HW event that swept central Chile with temperature records and wildfires. ERA5 tends to capture temperature extremes and the HW events at the inland stations; on the contrary, it has difficulties in capturing the maximum temperature variability at the coastal stations, which is plausible given the complex terrain features and confined coastal climate zone (only ∼ 7% of all grid boxes within central Chile). The composite HW days based on ERA5 reveals a mid-level trough-ridge dipole pattern exhibiting a blocking anticyclone on the surface over a large part of southwest South America. Relatively dry and warm easterly flow appears to accompany the anomalous warming in a large part of central Chile. The temporal evolution of the HW events yields a wave-like propagation pattern and enhancement of trough-ridge pattern along the South Pacific. This meridional dipole pattern is found to be largely associated with the Pacific South American pattern. In addition, the Madden–Julian Oscillation (MJO) appears to be a key component of the HW events in central Chile. In particular, while active MJO phases 2 and 7 promote sub-seasonal patterns that favor the South Pacific dipole mode, synoptic anomalies can superimpose on them and favor the formation of a migrating anticyclone over central-southern Chile and coastal lows over central Chile. Agreeing with the climatological findings, the extreme January 2017 HW analysis suggests that an eastward migratory mid-latitude trough-ridge pattern associated with MJO phase 2 was at work. We highlight that in addition to large- and synoptic-scale features, sub-synoptic processes such as coastal lows can have an important role in shaping the HW events and can lead to amplification of temperature extremes during the HW events. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. | |
| Multiscale physical background to an exceptional harmful algal bloom of Dinophysis acuta in a fjord system | Science of The Total Environment | Díaz, P.; Peréz-Santos, I.; Álvarez, G.; Garreaud, R.; Pinilla, E.; Díaz, M.; Sandoval, A.; Araya, M.; Álvarez, F.; Rengel, J.; Montero, P.; Pizarro, G.; López, L.; Iriarte, L.; Igor, G.; Reguera, B. | 2021 | Agua y Extremos | 10.1016/j.scitotenv.2021.145621 | https://linkinghub.elsevier.com/retrieve/pii/S0048969721006896 | 145621 | Vol: 773 | 00489697 | Thomson Reuters ISI (SCIE) | English | Dinophysis acuta produces diarrhetic shellfish poisoning (DSP) toxins and pectenotoxins (PTX). It blooms in thermally-stratified shelf waters in late summer in temperate to cold temperate latitudes. Despite its major contribution to shellfish harvesting bans, little effort has been devoted to study its population dynamics in Chilean Patagonia. In 2017–2018, mesoscale distribution of harmful algal species (75 monitoring stations) revealed the initiation (late spring) and seasonal growth of a dense D. acuta population in the Aysén region, with maximal values at Puyuhuapi Fjord (PF). Vertical phytoplankton distribution and fine-resolution measurements of physical parameters along a 25-km transect in February 16th identified a 15-km (horizontal extension) subsurface thin layer of D. acuta from 4 to 8 m depth. This layer, disrupted at the confluence of PF with the Magdalena Sound, peaked at the top of the pycnocline (6 m, 15.9 °C, 23.4 psu) where static stability was maximal. By February 22nd, it deepened (8 m, 15.5 °C; 23.62 psu) following the excursions of the pycnocline and reached the highest density ever recorded (664 × 103 cells L−1) for this species. Dinophysis acuta was the dominant Dinophysis species in all microplankton net-tows/bottle samples; they all contained DSP toxins (OA, DTX-1) and PTX-2. Modeled flushing rates showed that Puyuhuapi, the only fjord in the area with 2 connections with the open sea, had the highest water residence time. Long term climate variability in the Southern hemisphere showed the effects of a Southern Annular Mode (SAM) in positive mode (+1.1 hPa) overwhelming a moderate La Niña. These effects included positive spring precipitation anomalies with enhanced salinity gradients and summer drought with positive anomalies in air (+1 °C) and sea surface (+2 °C) temperature. Locally, persistent thermal stratification in PF seemed to provide an optimal physical habitat for initiation and bloom development of D. acuta. Thus, in summer 2018, a favourable combination of meteorological and hydrographic processes of multiple scales created conditions that promoted the development of a widespread bloom of D. acuta with its epicentre at the head of Puyuhuapi fjord. | |
| Más de 20 años de monitoreo del sistema de surgencia costera de Chile central | Universidad de Concepción | Farías, L.; Manríquez, V.; De la Maza, L. | 2021 | Zonas Costeras | 10.48665/udec/CMHMEQ | https://www.researchgate.net/publication/355484145_Mas_de_20_anos_de_monitoreo_del_sistema_de_surgencia_costera_de_Chile_central_final | El océano actúa como el regulador del estado medio climático en el planeta Tierra, absorbiendo calor, controlando la concentración de gases de efecto invernadero en la atmósfera y manteniendo el ciclo hidrológico que suministra agua dulce al planeta. El monitoreo del océano es necesario para comprender su dinámica a diferentes escalas temporales y espaciales, así como para cuantificar el impacto de los procesos globales como el cambio climático (CC) en su funcionamiento. El monitoreo permite finalmente dimensionar impactos y evaluar la vulnerabilidad de sus ecosistemas y comunidades costeras. Los humanos dependen del océano, debido a los múltiples servicios ecosistémicos que este entrega, i.e., pesca, acuicultura, provisión de productos naturales, purificación/desalinización de agua, protección de la costa, transporte y recreación/turismo, entre algunos. Este es el caso de Chile, un país con vocación oceánica altamente vulnerable al CC, pero con escaso monitoreo de océano y, por lo tanto, con limitada capacidad para estimar la intensidad de las amenazas, y para predecir impactos, herramienta esencial para adaptarse al CC y otros fenómenos. |
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| Temporal methane variability in the water column of an area of seasonal coastal upwelling: A study based on a 12 year time series | Progress in Oceanography | Farías, L.; Tenorio, S.; Sanzana, K.; Faundez, J. | 2021 | Zonas Costeras | 10.1016/j.pocean.2021.102589 | https://linkinghub.elsevier.com/retrieve/pii/S0079661121000768 | 102589 | Vol: 195 | 0079-6611 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Temporal distribution of dissolved CH4 was analysed in a zone of strong seasonal coastal upwelling off central Chile (36.5°S,73°W). Observations were taken from a twelve-year time series that included monthly sampling of the water at eight depths. CH4 concentration fluctuated between 1.75 and 100.9 nmol L-1 (or 67.11% and 3965% of saturation), with the highest levels at bottom waters, which increase as upwelling evolved. Three kind of CH4 profiles were identified; a classical diffusion–advection distribution, with bottom/surface CH4 concentration ratio > 2, was predominantly observed in ~ 54% of the all profiles and attributed to high CH4 production in the sediments during coastal upwelling season (austral spring-summer); a period of higher biological productivity, as well as in hypoxic/anoxic condition. In contrast, relatively homogeneous profiles (CH4 level ratio between bottom and surface depth < 2) was observed about ~ 46% of all profiles during periods of extreme vertical mixing (such as winter storms). Furthermore, irregular CH4 profile with superficial peaks occurring between the surface and 15–30 m depth was likely observed. These peaks indicated that local production rates exceed turbulent mixing rates, suggesting a rapid CH4 cycling due to microbial processes on the surface. Despite the fact that strong seasonality was observed in most oceanographic variables, according to favourable and non-favourable upwelling periods, only a weak seasonality was observed in CH4 content and its air-sea flux, the latter ranged from 1.27 to 47.02 µmol m−2 d-1 (mean ± SD: 10.94 ± 7.48). The annual weighted mean CH4 effluxes during upwelling (64%) and non-upwelling (36%) periods fluctuated from 1.66 to 6.22 mmol m−2 (mean ± SD: 3.40 ± 1.43), highlighting the importance of the continental shelf under the influence of coastal upwelling as a significant CH4 source toward the atmosphere. © 2021 |
| Spatial Distribution of Dissolved Methane Over Extreme Oceanographic Gradients in the Subtropical Eastern South Pacific (17° to 37°S) | Journal of Geophysical Research: Oceans | Farías, L.; Troncoso, M.; Sanzana, K.; Verdugo, J.; Masotti, I. | 2021 | Zonas Costeras | 10.1029/2020JC016925 | https://onlinelibrary.wiley.com/doi/10.1029/2020JC016925 | art: e2020JC016925 | Vol: 126 Issue: 5 | 2169-9275, 2169-9291 | Thomson Reuters ISI (SCIE) | English | Methane (CH4) is one of the most powerful greenhouse gases with the capacity to influence the Earth's radiative budget as well as contribute to atmospheric chemistry. Natural oceanic production makes up to ∼4% of the overall global CH4 emissions, however, there is uncertainty around the accuracy of this value due to a lack of accurate measurements. Such is the case in the Subtropical Eastern South Pacific Ocean (SESP), a region with pronounced chlorophyll-a and oxygen gradients, which in turn affect the microbial CH4 cycling. This study was conducted during spring-summer (2014–2016) in the SESP. The region (∼17°–37°S/71°–110°W) is separated into (i) eutrophic, (ii) mesotrophic, and (iii) oligotrophic areas, according to oceanographic and biogeochemical criteria. The SESP presents high CH4 zonal variability with levels ranging from 0.63 to 33.4 nmol L−1, corresponding to 29% and 1,423% saturation, respectively. High CH4 concentrations (>1,000% saturation) are observed in the narrow eutrophic area subjected to coastal upwelling. These conditions clearly differ to those observed in the extended oligotrophic subtropical gyre (∼100% saturation). Furthermore, CH4 also tends to accumulate in the mesotrophic area (with upto 1,423% saturation), where oceanographic conditions as stratification, mesoscale eddies and island mass effect could trigger the presence of a microbial biomass that may be able to induce CH4 regeneration. The CH4 efflux is estimated to be between 0.13 and 19.1 µmol m−2 d−1 (mean ± SD = 4.72 ± 4.67) and the SESP has an emission rate of ∼87.9 Gg CH4 yr−1. | |
| Extreme zonal and vertical gradients of nutrients and greenhouse gases in the subtropical Eastern South Pacific basin | Farías, Laura; Troncoso, Macarena | 2021 | Zonas Costeras | 10.1594/PANGAEA.933734 | https://doi.pangaea.de/10.1594/PANGAEA.933734 | Pangaea | English | Between October 12 and November 5, 2015, the Cimar 21 “Ocean Islands” cruise was developed, organized and managed by the Navy's Hydrographic and Oceanographic Service (SHOA). This cruise covered the zonal transect in the subtropical region of the Eastern South Pacific Basin from Caldera (27.00°S; 70.88°W) to near Rapa Nui Island (27.04°S; 109.31°W). This region is characterized by presenting very contrasting trophic systems; from the coastal zone with eutrophic (rich in nutrients), colder and suboxic ([O2] <22 µM); to ultra-oligotrophic (with undetectable nutrient levels Raimbault et al., 2008), warmer and oxygenated waters that belong to South Pacific Subtropical Gyre, which has the clearest waters of the global ocean (Morel et al., 2010). In addition to trophic gradient, the Eastern South Pacific region presents an oxygen minimum zone (OMZ (Fuenzalida et al, 2009) with marked oxygen gradients where various biogeochemical processes can recycle greenhouse gases such as nitrous oxide (N2O) (Trocoso et al., 2018) and even methane (CH4) (Farías et al., 2021). From a total of 19 stations sampled, we present a set of data collected between 0 and 500 m depth using a CTD rosette for physicochemical variables such as temperature, salinity and oxygen (obtained from the CTD) and nutrients (nitrite, nitrate, phosphate, silicate) and greenhouse gases N2O and CH4 (obtained from Niskin bottles mounted in an oceanographic rosette). The gas samples were analyzed by gas chromatography through a gas chromatograph (Schimadzu 17A) using an electron capture detector at 350ºC and connected to an autoanalyzer, while the CH4 samples were analyzed manually in a chromatograph gas with flame ionization detector (Agilent Model 6850 GC-Fid) with a Restek RT QS-Bond column (30 meters 053 mm ID, 20 μm Film) with a temperature of 40ºC and a column flow of 4mL min-1. Meanwhile, nutrient samples with micromolar concentration (≥ 1 µM) were analyzed using standard colorimetric techniques (Grasshoff et al., 1983) in a Seal AA3 segmented flow auto-analyzer, whereas when the nutrient concentration was submicromolar (< 1 µM) for samples of nitrite, nitrate, and phosphate in the gyre, the Seal AA3 segmented flow autoanalyzer was used coupled to two 50 cm Liquid waveridge capillary cells (LWCC, Type II), which allowed to increase the sensitivity of the detection spectrophotometric (Troncoso et al., 2018). | |||||
| Using Sentinel-2 and canopy height models to derive a landscape-level biomass map covering multiple vegetation types | International Journal of Applied Earth Observation and Geoinformation | Fassnacht, F.; Poblete-Olivares, J.; Rivero, L.; Lopatin, J.; Ceballos-Comisso, A.; Galleguillos, M. | 2021 | Cambio de Uso de Suelo | 10.1016/j.jag.2020.102236 | https://linkinghub.elsevier.com/retrieve/pii/S0303243420308795 | 102236 | Vol: 94 | 03032434 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Vegetation biomass is a globally important climate-relevant terrestrial carbon pool and also drives local hydrological systems via evapotranspiration. Vegetation biomass of individual vegetation types has been successfully estimated from active and passive remote sensing data. However, for many tasks, landscape-level biomass maps across several vegetation types are more suitable than biomass maps of individual vegetation types. For example, the validation of ecohydrological models and carbon budgeting typically requires spatially continuous biomass estimates, independent from vegetation type. Studies that derive biomass estimates across multiple vegetation or land-cover types to merge them into a single landscape-level biomass map are still scarce, and corresponding workflows must be developed. Here, we present a workflow to derive biomass estimates on landscape-level for a large watershed in central Chile. Our workflow has three steps: First, we combine field plot based biomass estimates with spectral and structural information collected from Sentinel-2, TanDEM-X and airborne LiDAR data to map grassland, shrubland, native forests and pine plantation biomass using random forest regressions with an automatic feature selection. Second, we predict all models to the entire landscape. Third, we derive a land-cover map including the four considered vegetation types. We then use this land-cover map to assign the correct vegetation type-specific biomass estimate to each pixel according to one of the four considered vegetation types. Using a single repeatable workflow, we obtained biomass predictions comparable to earlier studies focusing on only one of the four vegetation types (Spearman correlation between 0.80 and 0.84; normalized-RMSE below 16 % for all vegetation types). For all woody vegetation types, height metrics were amongst the selected predictors, while for grasslands, only Sentinel-2 bands were selected. The land-cover was also mapped with high accuracy (OA = 83.1 %). The final landscape-level biomass map spatially agrees well with the known biomass distribution patterns in the watershed. Progressing from vegetation-type specific maps towards landscape-level biomass maps is an essential step towards integrating remote-sensing based biomass estimates into models for water and carbon management. |
| Validation of a 9-km WRF dynamical downscaling of temperature and precipitation for the period 1980–2005 over Central South Chile | Theoretical and Applied Climatology | Fernández, A.; Schumacher, V.; Ciocca, I.; Rifo, A.; Muñoz, A.; Justino, F. | 2021 | Agua y Extremos | 10.1007/s00704-020-03416-9 | http://link.springer.com/10.1007/s00704-020-03416-9 | 361-378 | Vol: 143 Issue: 1-2 | 0177-798X, 1434-4483 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | In this paper, we evaluated a dynamical downscaling produced for Central South Chile (32°S–38°S) relative to climatic conditions between 1980 and 2005. Assessing the skill of dynamical downscaling relative to the present climate is key to determine the degree of confidence on regional climatic projections. We used the Weather Research and Forecasting model to simulate that period at ~ 9 km grid-cell size, forced by the bias-corrected Community Earth System Model. Results indicated that the dynamical downscaling adequately reproduced spatio-temporal features of the climate within the region. Temperature showed a positive bias at the annual scale while the opposite occurred for precipitation. The bias varied when the comparison was performed relative to a gridded product or instrumental records from weather stations. At the monthly scale, the model failed to capture long-term trends relative to the gridded dataset while reproducing spatial patterns, especially for temperature. We found a generally statistically significant spatial clustering of the monthly mean bias that can support implementation and application of dynamical downscaling and bias-correction methods that account for the distinct climatic features of the study area. In particular, the strip 34°S–35°S presented features that are coincident with previous findings suggesting this latitude to be a boundary between different climate regimes north and south. According to our results, we assert that this dynamical downscaling is comparable with other available databases and thus can be utilized in future studies as an additional and independent source of analysis, contributing to a balanced appraisal of climate scenarios for policymaking within the region. |
| Explorador del Atlas de Sequías de Sudamérica, https://sada.cr2.cl | Ferrada, A.; Christie, D.; Muñoz, F.; Reyes, A.; Garreaud, R.; Bustos, S. | 2021 | Agua y Extremos | 10.13140/RG.2.2.14020.35209 | http://rgdoi.net/10.13140/RG.2.2.14020.35209 | ResearchGate | Spanish | ||||||
| Sensitivity of Water Price Elasticity Estimates to Different Data Aggregation Levels | Water Resources Management | Flores Arévalo, Y.; Ponce Oliva, R.; Fernández, F.; Vásquez-Lavin, F. | 2021 | Cambio de Uso de Suelo | 10.1007/s11269-021-02833-3 | https://link.springer.com/10.1007/s11269-021-02833-3 | 2039-2052 | Vol: 35 Issue: 6 | 0920-4741, 1573-1650 | Thomson Reuters ISI (SCIE) | English | The empirical literature on residential water demand employs various data aggregation methods, which depend on whether the aggregation is over consumption, sociodemographic variables, or both. In this study, we distinguish three dataset types—aggregated data, disaggregated data, and semi-aggregated data—to compare the consequences of using a large sample of semi-aggregated data vis-à-vis a small sample of fully disaggregated data on the water price elasticity estimates. We also analyze whether different aggregation levels in the sociodemographic variables affect the water price elasticity estimates when the number of observations is fixed. We employ a discrete-continuous choice model that considers that consumers face an increasing block price structure. Our results demonstrate that the water price elasticities depend upon the level of aggregation of the data used and the sample size. We also find that the water price elasticities are statistically different when comparing a large semi-aggregated sample with a small disaggregated sample. | |
| Landscape Engineering Impacts the Long-Term Stability of Agricultural Populations | Human Ecology | Freeman, J.; Anderies, J.; Beckman, N.; Robinson, E.; Baggio, J.; Bird, D.; Nicholson, C.; Finley, J.; Capriles, J.; Gil, A.; Byers, D.; Gayo, E.; Latorre, C. | 2021 | Ciudades Resilientes | 10.1007/s10745-021-00242-z | https://link.springer.com/10.1007/s10745-021-00242-z | 369-382 | Vol: 49 Issue: 4 | 0300-7839, 1572-9915 | Thomson Reuters ISI (SSCI) | English | Explaining the stability of human populations provides knowledge for understanding the resilience of human societies to environmental change. Here, we use archaeological radiocarbon records to evaluate a hypothesis drawn from resilience thinking that may explain the stability of human populations: Faced with long-term increases in population density, greater variability in the production of food leads to less stable populations, while lower variability leads to more stable populations. However, increased population stability may come with the cost of larger collapses in response to rare, large-scale environmental perturbations. Our results partially support this hypothesis. Agricultural societies that relied on extensive landscape engineering to intensify production and tightly control variability in the production of food experienced the most stability. Contrary to the hypothesis, these societies also experienced the least severe population declines. We propose that the interrelationship between landscape engineering and increased political-economic complexity reduces the magnitude of population collapses in a region. | |
| Crossing a critical threshold: Accelerated and widespread land use changes drive recent carbon and nitrogen dynamics in Vichuquén Lake (35°S) in central Chile | Science of The Total Environment | Fuentealba, M.; Latorre, C.; Frugone-Álvarez, M.; Sarricolea, P.; Godoy-Aguirre, C.; Armesto, J.; Villacís, L.; Laura Carrevedo, M.; Meseguer-Ruiz, O.; Valero-Garcés, B. | 2021 | Ciudades Resilientes | 10.1016/j.scitotenv.2021.148209 | https://linkinghub.elsevier.com/retrieve/pii/S0048969721032800 | 148209 | Vol: 791 | 00489697 | Thomson Reuters ISI (SCIE) | English | Global afforestation/deforestation processes (e.g., Amazon deforestation and Europe afforestation) create new anthropogenic controls on carbon cycling and nutrient supply that have not been fully assessed. Here, we use a watershed-lake dynamics approach to investigate how human-induced land cover changes have altered nutrient transference during the last 700 years in a mediterranean coastal area (Vichuquén Lake). We compare our multiproxy reconstruction with historical documentation and use satellite images to reconstruct land use/cover changes for the last 45 years. Historical landscape changes, including those during the indigenous settlements, Spanish conquest, and the Chilean Republic up to mid-20th century did not significantly alter sediment and nutrient fluxes to the lake. In contrast, the largest changes in the lake-watershed system occurred in the mid-20th century and particularly after the 1980s–90s and were characterized by a large increase in total nitrogen and organic carbon fluxes as well as negative shifts in sediment δ15N and δ13C values. This shift was coeval with the largest land cover transformation in the Vichuquén watershed, as native forests nearly disappeared while anthropogenic tree plantations expanded up to 60% of the surface area. © 2021 Elsevier B.V. | |
| He Antropoceno i a Tire: he mata ꞌite he haka pūai | Gallardo, L.; Rudnick, A.; Barraza, J.; Fleming, Z.; Rojas, M.; Gayó, E.; Aguirre, C.; Farías, L.; Boisier, J.; Garreaud, R.; Barría, P.; Miranda, A.; Lara, A.; Gómez, S.; Arriagada, R. | 2021 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://bit.ly/3sAJOdv | Centro de Ciencia del Clima y la Resiliencia mew (CR)2, ta iñ kvzawkan mew zujiyiñ fey ta nvxamkagelu Anxopozeno zugu mew ta iñ inarumeael ka ta iñ gvnezuamael. Femgeci ta cijkatuyiñ cumgeci cambio climático vñfitumapukey kiñeke mapu mew Cile mew fanten mew, ta iñ kejuael zugu mew cew ta cijkatugekey ka gvnezuamgekey weke rvpv ta iñ kvme wimturpuael zugu mew mvlelu fanten mew. Wvnelu ta inarumeyiñ ta pu registro geohistórico pegeltulu cumgeci ta wizvmapukunurpukefuy kuyfi mew ta cegen mapu mew Cile pigelu faciantv; fey mew kvmeafuy wiñokintuliyiñ feyti mew kuyfi mew rupalu ka kejuafulu sistemas socio-ecológicos zugu mew ta kvpaialu. |
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| Anxopozeno Cile mew: Ta iñ inazuamfiel ka cumgeci amulerpuael | Gallardo, L.; Rudnick, A.; Barraza, J.; Fleming, Z.; Rojas, M.; Gayó, E.; Aguirre, C.; Farías, L.; Boisier, J.; Garreaud, R.; Barría, P.; Miranda, A.; Lara, A.; Gómez, S.; Arriagada, R. | 2021 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://bit.ly/3FyHHL0 | Centro de Ciencia del Clima y la Resiliencia mew (CR)2, ta iñ kvzawkan mew zujiyiñ fey ta nvxamkagelu Anxopozeno zugu mew ta iñ inarumeael ka ta iñ gvnezuamael. Femgeci ta cijkatuyiñ cumgeci cambio climático vñfitumapukey kiñeke mapu mew Cile mew fanten mew, ta iñ kejuael zugu mew cew ta cijkatugekey ka gvnezuamgekey weke rvpv ta iñ kvme wimturpuael zugu mew mvlelu fanten mew. Wvnelu ta inarumeyiñ ta pu registro geohistórico pegeltulu cumgeci ta wizvmapukunurpukefuy kuyfi mew ta cegen mapu mew Cile pigelu faciantv; fey mew kvmeafuy wiñokintuliyiñ feyti mew kuyfi mew rupalu ka kejuafulu sistemas socio-ecológicos zugu mew ta kvpaialu. |
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| Disentangling the effect of future land use strategies and climate change on streamflow in a mediterranean catchment dominated by tree plantations | Journal of Hydrology | Galleguillos, M.; Gimeno, F.; Puelma, C.; Zambrano-Bigiarini, M.; Lara, A.; Rojas, M. | 2021 | Agua y Extremos; Cambio de Uso de Suelo; Gobernanza e Interfaz Ciencia y Política | 10.1016/j.jhydrol.2021.126047 | https://linkinghub.elsevier.com/retrieve/pii/S0022169421000949 | 126047 | Vol: 595 | 0022-1694 | Thomson Reuters ISI (SCIE) | English | Climate change (CC) along with Land Use and Land Cover Change (LULCC) have a strong influence in water availability in already fragile Mediterranean ecosystems. In this work the Soil and Water Assessment Tool (SWAT) was implemented for the 2006–2018 period in a rainfed catchment of central Chile (36°) to test the hypothesis that adaptive plantation strategies could mitigate the impacts of climate change and increase streamflow. We also hypothesize that afforestation with exotic tree plantations will reduce water availability in Mediterranean catchments, acting in synergy with climate change. Five LULCC scenarios are analyzed: i) current long-term national Forest Policy (FP), ii) extreme scenario (EX) with large afforestation surfaces, both including the replacement of native shrublands with Pinus radiata; iii) adaptive plantation management scenario (FM), with lower planting density, iv) forced land displacement scenario (FLD), where plantations at the headwaters are moved to lowland areas and replaced with native shrublands, and v) pristine scenario (PR), with only native vegetation. Each LULCC scenario was run with present climate and with projections of different CMIP5 climate models under the RCP 8.5 scenario for the period 2037–2050, and then compared against simulations based on the present land cover and climate. Simulations with the five LULCC scenarios (FP, EX, FM, FLD and PR) with present climate resulted in variations of −2.5, −17.3, 0, 2.3 and 10.9% on mean annual streamflow (Q), while simulations with the current land cover and CC projections produced a 32.1% decrease in mean annual Q. The joint impact of CC and LULCC leads to changes in mean annual Q ranging from −46.2% (EX) to –23.3% (PR). Afforestation with exotic pines will intensify the reduction in water yield, while conservative scenarios focused on native forests protection and restoration could partially mitigate the effect of CC. We make a strong call to rethink current and future land management strategies to cope with lower water availability in a drier future. © 2021 Elsevier B.V. | |
| The South Pacific Pressure Trend Dipole and the Southern Blob | Journal of Climate | Garreaud, R.; Clem, K.; Veloso, J. | 2021 | Agua y Extremos | 10.1175/JCLI-D-20-0886.1 | https://journals.ametsoc.org/view/journals/clim/34/18/JCLI-D-20-0886.1.xml | 7661-7676 | Vol: 34 Issue: 18 | 0894-8755, 1520-0442 | Thomson Reuters ISI (SCIE) | English | During the last four decades, the sea level pressure has been decreasing over the Amundsen–Bellingshausen Sea (ABS) region and increasing between 30° and 40°S from New Zealand to Chile, thus forming a pressure trend dipole across the South Pacific. The trends are strongest in austral winter and have influenced the climate of West Antarctica and South America. The pressure trends have been attributed to decadal variability in the tropics, expansion of the Hadley cell, and an associated positive trend of the southern annular mode, but these mechanisms explain only about half of the pressure trend dipole intensity. Experiments conducted with two atmospheric models indicate that upper ocean warming over the subtropical southwest Pacific (SSWP), termed the Southern Blob, accounts for about half of the negative pressure trend in the ABS region and nearly all the ridging/drying over the eastern subtropical South Pacific, thus contributing to the central Chile megadrought. The SSWP warming intensifies the pressure trend dipole through warming the troposphere across the subtropical South Pacific and shifting the midlatitude storm track poleward into the ABS. Multidecadal periods of strong SSWP warming also appear in fully coupled preindustrial simulations, associated with a pressure trend dipole and reduction in rainfall over the central tropical Pacific, thus suggesting a natural origin of the Southern Blob and its teleconnection. However, the current warming rate exceeds the range of natural variability, implying a likely additional anthropogenic contribution. | |
| Automated Low-Cost LED-Based Sun Photometer for City Scale Distributed Measurements | Remote Sensing | Garrido, C.; Toledo, F.; Diaz, M.; Rondanelli, R. | 2021 | Zonas Costeras | 10.3390/rs13224585 | https://www.mdpi.com/2072-4292/13/22/4585 | 4585 | Vol: 13 Issue: 22 | 2072-4292 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | We propose a monochromatic low-cost automatic sun photometer (LoCo-ASP) to perform distributed aerosol optical depth (AOD) measurements at the city scale. This kind of network could fill the gap between current automatic ground instruments—with good temporal resolution and accuracy, but few devices per city and satellite products—with global coverage, but lower temporal resolution and accuracy-. As a first approach, we consider a single equivalent wavelength around 408 nm. The cost of materials for the instrument is around 220 dollars. Moreover, we propose a calibration transfer for a pattern instrument, and estimate the uncertainties for several units and due to the internal differences and the calibration process. We achieve a max MAE of 0.026 for 38 sensors at 408 nm compared with AERONET Cimel; a mean standard deviation of 0.0062 among our entire sensor for measurement and a calibration uncertainty of 0.01. Finally, we perform city-scale measurements to show the dynamics of AOD. Our instrument can measure unsupervised, with an expected error for AOD between 0.02 and 0.03. |
| Summary for policymakers. The air we breathe: past, present and future - PM2.5 air pollution in Central and Southern Chile . | Gayo, E.; Osses, M.; Urquiza, A.; Arriagada, R.; Huneeus, N.; Valdés, M.; Barraza, J.; Rudnick, A. | 2021 | Cambio de Uso de Suelo; Ciudades Resilientes | https://bit.ly/32xerpf | Air quality is a complex problem involving not only physical-chemical factors, but also sociocultural, economic, and institutional variables. The report “The air we breathe: past, present and future – PM2.5 air pollution in Central and Southern Chile” focuses on the impacts and the role played by the residential sector and its PM2.5 emissions, taking the above factors and variables into account. This interdisciplinary research integrates information from multiple databases, numerical simulations, and interviews and workshops with diff erent stakeholders in order to characterize not only current air quality but also the evolution of air pollution since pre-Colombian times, and the factors influencing its future evolution. |
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| Resumen para tomadores de decisiones. El aire que respiramos: pasado, presente y futuro - Contaminación atmosférica por MP2,5 en el centro y sur de Chile. | Gayo, E.; Osses, M.; Urquiza, A.; Arriagada, R.; Huneeus, N.; Valdés, M.; Barraza, J.; Rudnick, A. | 2021 | Cambio de Uso de Suelo; Ciudades Resilientes | https://bit.ly/3z0dxO4 | Not indexed | La calidad del aire es un problema complejo que no responde solo a factores físico-químicos, sino que también a variables socioculturales, económicas e institucionales. El informe “El aire que respiramos: pasado, presente y futuro – Contaminación atmosférica por MP2,5 en el centro y sur de Chile” se centra en los impactos y el rol que juega el sector residencial y sus emisiones de MP2,5 considerando estos diferentes factores. Esta investigación interdisciplinaria integra múltiples bases de datos, simulaciones numéricas, resultados de entrevistas y talleres con diversos actores para caracterizar no solo la calidad del aire actual, sino que también la evolución de la contaminación atmosférica desde épocas precolombinas y los factores que influyen en su evolución futura. |
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| High- and low-latitude forcings drive Atacama Desert rainfall variations over the past 16,000 years | Science Advances | González-Pinilla, F.; Latorre, C.; Rojas, M.; Houston, J.; Rocuant, M.; Maldonado, A.; Santoro, C.; Quade, J.; Betancourt, J. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1126/sciadv.abg1333 | https://www.science.org/doi/10.1126/sciadv.abg1333 | art: eabg1333 | Vol: 7 Issue: 38 | 2375-2548 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Late Quaternary precipitation dynamics in the central Andes have been linked to both high- and low-latitude atmospheric teleconnections. We use present-day relationships between fecal pellet diameters from ashy chinchilla rats (Abrocoma cinerea) and mean annual rainfall to reconstruct the timing and magnitude of pluvials (wet episodes) spanning the past 16,000 years in the Atacama Desert based on 81 14C-dated A. cinerea paleomiddens. A transient climate simulation shows that pluvials identified at 15.9 to 14.8, 13.0 to 8.6, and 8.1 to 7.6 ka B.P. can be linked to North Atlantic (high-latitude) forcing (e.g., Heinrich Stadial 1, Younger Dryas, and Bond cold events). Holocene pluvials at 5.0 to 4.6, 3.2 to 2.1, and 1.4 to 0.7 ka B.P. are not simulated, implying low-latitude internal variability forcing (i.e., ENSO regime shifts). These results help constrain future central Andean hydroclimatic variability and hold promise for reconstructing past climates from rodent middens in desert ecosystems worldwide. |
| Seasonal precipitation in South Central Chile: trends in extreme events since 1900 | Atmósfera | González-Reyes, Á.; Jacques-Coper, M.; Muñoz, A. | 2021 | Agua y Extremos; Zonas Costeras | 10.20937/ATM.52871 | https://www.revistascca.unam.mx/atm/index.php/atm/article/view/52871 | 371-384 | Vol: 34 Issue: 4 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access; Hybrid Gold Open Access | English | We study a regional precipitation time series, built upon seven meteorological records from South Central Chile (SCC; 37° - 42°S), which together cover the period 1900 - 2019. As a first objective, we investigated changes in the return period (RP) of dry ( |
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| Unveiling Ecological and Genetic Novelty within Lytic and Lysogenic Viral Communities of Hot Spring Phototrophic Microbial Mats | Microbiology Spectrum | Guajardo-Leiva, S.; Santos, F.; Salgado, O.; Regeard, C.; Quillet, L.; Díez, B. | 2021 | Zonas Costeras | 10.1128/Spectrum.00694-21 | https://journals.asm.org/doi/abs/10.1128/Spectrum.00694-21 | arte00694-21 | Vol: 9 Issue: 3 | 2165-0497 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Hot springs harbor microbial communities dominated by a limited variety of microorganisms and, as such, have become a model for studying community ecology and understanding how biotic and abiotic interactions shape their structure. Viruses in hot springs ... |
| Leaf Thermal and Chemical Properties as Natural Drivers of Plant Flammability of Native and Exotic Tree Species of the Valparaíso Region, Chile | International Journal of Environmental Research and Public Health | Guerrero, F.; Hernández, C.; Toledo, M.; Espinoza, L.; Carrasco, Y.; Arriagada, A.; Muñoz, A.; Taborga, L.; Bergmann, J.; Carmona, C. | 2021 | Agua y Extremos | 10.3390/ijerph18137191 | https://www.mdpi.com/1660-4601/18/13/7191 | 7191 | Vol: 18 Issue: 13 | 1660-4601 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | Forest fires are one of the main environmental threats in Chile. Fires in this Mediterranean climate region frequently affect native forests and exotic plantations, including in several cases urban and rural settlements. Considering the scarcity of information regarding the fire response dynamics of tree species that are frequently affected by fires, this study aims to establish a flammability classification according to the evolution of the fire initiation risk presented by the most affected forest species in the Valparaíso region. Three exotic species, Eucalyptus globulus, Pinus radiata, and Acacia dealbata, and two native species, Cryptocarya alba and Quillaja saponaria, were studied. Flammability assays indicate that E. globulus, A. dealbata, and C. alba are extremely flammable, whereas P. radiata and Q. saponaria are flammable. Furthermore, E. globulus and A. dealbata have the highest heating values while Q. saponaria has the lowest values. The extreme flammability of E. globulus, A. dealbata, and C. alba indicates a high susceptibility to ignite. Furthermore, the high heat of combustion of E. globulus and A. dealbata can be associated with a high energy release, increasing the risk of fires spreading. In contrast, Q. saponaria has the lowest predisposition to ignite and capacity to release heat. Accordingly, this work shows that all studied tree species contain organic metabolites that are potentially flammable (sesquiterpenes, aliphatic hydrocarbons, alcohol esters, ketones, diterpenes, and triterpenes) and can be considered as drivers of flammability in vegetation. Finally, these preliminary results will aid in the construction of more resilient landscapes in the near future. |
| Paving the road for electric vehicles: Lessons from a randomized experiment in an introduction stage market | Transportation Research Part A: Policy and Practice | Guevara, C.; Figueroa, E.; Munizaga, M. | 2021 | Ciudades Resilientes | 10.1016/j.tra.2021.09.011 | https://linkinghub.elsevier.com/retrieve/pii/S096585642100241X | 326-340 | Vol: 153 | 09658564 | Thomson Reuters ISI (SCIE; SSCI) | English | We study attitudes, perceptions, and valuations of a convenience sample of Chilean employees from an electric distribution company who applied for a subsidized electric vehicle (EV) acquisition program. The subsidy was randomly assigned among the interested applicants. We use this data in an experiment to assess the impact that being a user, or a non-user of an EV has on the factors under study, using focus groups and a stated preference (SP) experiment. In the focus groups, users mentioned relatively more benefits and barriers of EVs, while non-users spontaneously stated that a limited charging network at the urban level could be an issue. The SP survey suggested that being a user did not trigger a change in environmental attitudes; on the other hand, it significantly boosted perceptions of maintenance costs and driving range. Additionally, discrete choice models estimated from the SP data suggested a possibly null willingness to pay for urban charging infrastructure, expressed as a percentage of current gas stations, among the user group. We discuss possible policy implications that can be inferred from this analysis, considering the size and source limitations of the available sample. © 2021 Elsevier Ltd | |
| Transdisciplinary university in the framework of the knowledge society. Discursive tensions within Universidad de Chile | Pensamiento Educativo: Revista de Investigación Educacional Latinoamericana | Henriquez, A.; Billi, M.; Faúndez, V.; Labraña, J.; Neira Espinoza, C.; Urquiza, A. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.7764/PEL.58.1.2021.10 | http://ojs.uc.cl/index.php/pel/article/view/29137 | Vol: 58 Issue: 1 | Not indexed | All Open Access; Gold Open Access | English | En el marco de las transformaciones sociales contemporáneas, y del nuevo rol adoptado por las universidades, la transdisciplina ha ido ganando un reconocimiento creciente como aproximación para comprender fenómenos que no pueden ser abordados por el modelo tradicional de especialización disciplinar, como el cambio climático, la desigualdad o, recientemente, las pandemias. Sin embargo, existe escaso estudio de experiencias específicas que ayuden a entender qué implica, qué finalidad tiene y cómo puede lograrse una mayor focalización transdisciplinaria en las universidades. Para reducir esta brecha, este artículo analiza los resultados de un diálogo participativo realizado al interior de la Universidad de Chile, examinando distintas narrativas respecto de la emergencia, oportunidades y obstáculos de la transdisciplina; los que, a su vez, dicen relación con las dinámicas históricas, organizacionales y culturales propias de la trayectoria adoptada por esta institución, y la educación superior en general, en el país: i) el compromiso social, inscrito en la tradición y misión académica de la universidad pública; ii) una promesa de novedad, innovación y transformación del quehacer científico y académico, asociada al modelo emergente de universidad emprendedora; y iii) la creciente demanda avanzada para una reforma profunda del sistema de educación superior en el país. | ||
| Variación en la intensidad de la isla de calor urbana por efecto del cambio climático en ciudades chilenas | Geographicalia | Henríquez Ruiz, C.; Smith, P.; Contreras, P.; Qüense, J. | 2021 | Ciudades Resilientes | 10.26754/ojs_geoph/geoph.2021735114 | https://papiro.unizar.es/ojs/index.php/geographicalia/article/view/5114 | 133-154 | Issue: 73 | 2386-3021, 0210-8380 | Latindex | La Isla de Calor Urbano (ICU) es la principal característica del clima urbano y se define como la diferencia entre la temperatura urbana y la temperatura rural. Su existencia se explica por el diseño y materiales de construcción de la ciudad, superficies impermeables y no evapotranspirantes, y sus efectos son de diversa índole. La magnitud e intensidad de la ICU depende, a su vez, del tamaño de la ciudad y por ello, del volumen de población concentrada espacialmente. El objetivo de esta investigación es proponer una metodología que permita estimar la intensidad máxima de la ICU presente y futura mediante una aproximación de múltiples modelos (climáticos y de usos de suelo) y considerando los efectos del cambio climático. Los resultados demuestran que la ICU promedio de las principales ciudades chilenas analizadas es consistente con valores de estudios internacionales, destacando el caso del Gran Santiago que llegaría a tener una ICU mayor 10 ºC. | ||
| The last glacial termination in northwestern Patagonia viewed from the Lago Fonk (∼40°S) record | Quaternary Science Reviews | Henríquez, C.; Moreno, P.; Dunbar, R.; Mucciarone, D. | 2021 | Agua y Extremos | 10.1016/j.quascirev.2021.107197 | https://linkinghub.elsevier.com/retrieve/pii/S0277379121004042 | 107197 | Vol: 271 | 02773791 | Thomson Reuters ISI (SCIE) | English | The anatomy of the Last Glacial Termination (T1) in the southern mid-latitudes, and its relationship with changes in the Southern Westerly Winds (SWW), offers empirical constraints for understanding the mechanisms involved in the transition from the Last Glacial Maximum into the current interglacial. Northwestern Patagonia (40°-44°S) is a sensitive region for monitoring past changes in the SWW, the Patagonian Ice Sheet, terrestrial ecosystems, and fire regimes through T1. Here we present results from Lago Fonk (∼40°S) to examine the structure of T1 based on the palynological, macroscopic charcoal, elemental, and isotopic composition of organic lake sediments. We observe an instantaneous establishment of Nothofagus-dominated forests at the onset of T1, followed by a diversification and densification trend that culminated with the establishment of thermophilous, Myrtaceae-dominated North Patagonian rainforests between ∼15.6–14.7 cal ka BP. The expansion of the conifer Podocarpus nubigena marks a shift to cool-temperate and hyperhumid conditions, coeval with high lake levels and enhanced algal productivity between ∼14.7–11.9 cal ka BP. Stand-replacing fires, driven by enhanced seasonality or high-frequency rainfall variability, started at ∼12.4 cal ka BP and catalyzed the rapid spread of Weinmannia trichosperma. Subsequent warming and a decline in precipitation at ∼11.4 cal ka BP led to intense fire activity, lake-level lowering, and establishment of the Valdivian rainforest trees Eucryphia/Caldcluvia. Our results suggest a coherent linkage between changes documented in the amphi south Pacific region and Antarctic ice cores during T1. This implies a zonal and hemispheric response to changes in the position/intensity of the SWW that emphasizes their central role as a key driver of the hemispheric and global climate evolution through T1. | |
| The role of climate and disturbance regimes upon temperate rainforests during the Holocene: A stratigraphic perspective from Lago Fonk (∼40°S), northwestern Patagonia | Quaternary Science Reviews | Henríquez, C.; Moreno, P.; Lambert, F.; Alloway, B. | 2021 | Agua y Extremos; Ciudades Resilientes | 10.1016/j.quascirev.2021.106890 | https://linkinghub.elsevier.com/retrieve/pii/S0277379121000974 | 106890 | Vol: 258 | 02773791 | Thomson Reuters ISI (SCIE) | English | Climate and disturbance regimes play key roles in shaping the structure, composition and functioning of terrestrial ecosystems. Despite this importance, very few stratigraphic studies in the temperate rainforests from northwestern Patagonia have explored this relationship in detail along a time continuum through the entire Holocene. Here we present a high-resolution fossil pollen and charcoal record from Lago Fonk (median resolution: 20 years), a small closed-basin lake in the lowlands of the Chilean Lake District (41°S), where wildfires and explosive volcanism have intermittently taken place during the Holocene, along with pronounced human-induced disturbance in post-colonial time. Our results show persistence of temperate rainforest throughout the Holocene, with changes in the composition and structure of Valdivian rainforests (VRF) at millennial timescales. We detect centennial-scale alternations in dominance between the VRF tree Eucryphia/Caldcluvia and generalist trees found in VRF and North Patagonian rainforests after ∼6.5 cal ka BP. Intervals dominated by VRF coincide with enhanced fire occurrence signaling negative hydroclimate anomalies with a mean duration of ∼150 years, which alternate with positive hydroclimate anomalies lasting ∼312 years on average. Our results suggest that the magnitude and rapidity of vegetation changes detected at 10.2–9.9, 4.0–3.0, ∼1.0, and ∼0.7 cal ka BP were amplified by disturbance regimes, and led to the establishment and maintenance of Eucryphia/Caldcluvia-dominated forests in the Longitudinal Valley of the Chilean Lake District. On several occasions the higher incidence of fire disturbance during warm/dry climate intervals coincided with episodes of heightened explosive volcanic activity from multiple eruptive centers within the Southern Andean Volcanic Zone. |
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| Estimating coastal flood hazard of Tossa de Mar, Spain: a combined model – data interviews approach | Natural Hazards | Hernandez-Mora, M.; Meseguer-Ruiz, O.; Karas, C.; Lambert, F. | 2021 | Ciudades Resilientes | 10.1007/s11069-021-04914-3 | https://link.springer.com/article/10.1007/s11069-021-04914-3 | 2153-2171 | Vol: 109 Issue: 3 | 0921-030X, 1573-0840 | Thomson Reuters ISI (SCIE) | English | Human settlements in coastal areas are highly vulnerable to extreme events, especially in the Mediterranean area, which houses a large number of tourists during the summer and autumn months. It is important to carry out hazard studies at local scale to improve our understanding of natural and anthropogenic processes involved in episodes of coastal fooding. We reconstruct and characterize an extreme weather event in Tossa de Mar (northeastern Spain) and the subsequent urban fooding that occurred in 2008. Our results show food heights up to 1.27 m, with the maximum occurring between 24 and 64 h after the start of the event. This is broadly consistent with the reconstructions obtained through interviews and photographs. Based on model simulations, we produce a hazard map for the town based on hydrodynamic scenarios for diferent return periods. We show that the southern part of the town is more susceptible to fooding, whereas the northern part is relatively resilient to extreme events. We recommend the adaption of a currently existing dune by adding vegetation and slightly increasing its height. This low economic cost action would signifcantly reduce fooding and increase resilience in this area. |
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| Simulación hidrológica del caudal del estero Batuco en la microcuenca agroforestal Batuco (Ránquil, Región del Ñuble, Chile) bajo condiciones climáticas presentes y futuras | Ciencia & Investigación Forestal | Hormazábal, V.; Vargas Rojas, V.; Abarca, R.; Little Cárdenas, C.; Rivera, D.; Carrasco, N.; Villalobos Volpi, E. | 2021 | Cambio de Uso de Suelo | 10.52904/0718-4646.2021.546 | https://revista.infor.cl/index.php/infor/article/view/546 | 3-22 | Vol: 27 Issue: 2 | 0718-4646, 0718-4530 | Latindex | Se estima el comportamiento del caudal del estero Batuco, principal afluente de la microcuenca agroforestal Batuco en la Comuna de Ránquil, entre enero de 1975 y diciembre de 2064, en el escenario del cambio climático RCP8.5. Para tal efecto se simuló hidrológicamente la microcuenca Batuco, usando el modelo y software en versión gratuita WEAP. La información de entrada del modelo para estimar el caudal simulado provino de distintas bases de datos, tanto in situ como de reanálisis cercano a la zona de estudio, así como de datos aproximados del consumo (habitantes y cultivos). Se crearon series temporales para la precipitación y temperatura con los datos in situ, para posteriormente usarse como base para aplicar una corrección de sesgo a los datos de reanálisis Arclim. Los resultados son una primera aproximación que podrá ser mejorada cuando se pueda calibrar in situ con datos de caudal observado, los cuales actualmente no existen para la zona de estudio. No obstante, evidencian tendencias claras a la reducción sostenida de los caudales. Se determinó que el caudal simulado del estero Batuco marca una pendiente negativa en el periodo de estudio (1975-2064) de ≈−6,3 L/s por década, que se manifiesta también para todas las temporadas del año. Las anomalías estandarizadas de los promedios por cada 10 años, muestran en el periodo de 1980 un valor ≈ 1,2 desviaciones estándar con respecto a la media de la serie, mientras que en el periodo del 2060 se alcanza un valor ≈ -1,5. Las anomalías estandarizadas de las pendientes por cada 10 años sugieren un comportamiento cíclico, donde su amplitud disminuye con el tiempo para toda la serie y las diferentes temporadas del año. |
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| Diversifying Chile’s climate action away from industrial plantations | Environmental Science & Policy | Hoyos-Santillan, J.; Miranda, A.; Lara, A.; Sepulveda-Jauregui, A.; Zamorano-Elgueta, C.; Gómez-González, S.; Vásquez-Lavín, F.; Garreaud, R.; Rojas, M. | 2021 | Agua y Extremos; Cambio de Uso de Suelo; Gobernanza e Interfaz Ciencia y Política | 10.1016/j.envsci.2021.06.013 | https://linkinghub.elsevier.com/retrieve/pii/S1462901121001738 | 85-89 | Vol: 124 | 14629011 | Thomson Reuters ISI (SCIE) | English | As president of the Climate Change Conference of the Parties, Chile has advocated for developing ambitious commitments to mitigate greenhouse gas emissions to achieve carbon-neutrality by 2050. However, Chile’s motivations and ambitious push to reach carbon-neutrality are complicated by a backdrop of severe drought, climate change impacts (i.e., wildfires, tree mortality), and the use of industrial plantations as a mitigation strategy. This has become more evident as widespread and severe wildfires have impacted large areas of industrial plantations, transforming the land-use, land-use change, and forestry sector from a carbon sink to a net carbon source. Consequently, Chile must diversify its climate actions to achieve carbon-neutrality. Nature-based solutions, including wetlands-peatlands and oceans, represent alternative climate actions that can be implemented to tackle greenhouse gas emissions at a national level. Diversification, however, must guarantee Chile’s long-term carbon sequestration capacity without compromising the ecological functionality of biodiverse treeless habitats and native forest ecosystems. |
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| Intraseasonal teleconnections leading to heat waves in central Chile | International Journal of Climatology | Jacques‐Coper, M.; Veloso‐Aguila, D.; Segura, C.; Valencia, A. | 2021 | Zonas Costeras | 10.1002/joc.7096 | https://onlinelibrary.wiley.com/doi/10.1002/joc.7096 | 4712-4731 | Vol: 41 Issue: 9 | 0899-8418, 1097-0088 | Thomson Reuters ISI (SCIE) | English | The ability to anticipate meteorological extreme events beyond the synoptic range of ~1 week offers direct applications, for example, to limit their ecological and socioeconomical impacts. This study focuses on precursors of summer (December–February, DJF) warm events, particularly heat waves, in central Chile (CCh), which are typically induced by low-level anticyclonic anomalies located to the south of this region. Considering that such atmospheric configuration can be part of a large-scale wave-train circulation pattern located upstream of CCh, we investigate signals that might provide guidance concerning the genesis of warm events in CCh. For a historical period (DJF 1872–2010) based on the 20th century reanalysis version 2 (20CR), our results present teleconnections that indicate higher probabilities of occurrence of such warm events with respect to expected climatological values. These signals can be monitored at least ~2 weeks in advance. Specifically, we explore the relationship between warm events in CCh and (a) the Madden-Julian Oscillation (MJO) as a tropical source of variability, and (b) an extra-tropical index (ETI), representative of the internal dynamics of the Southern Hemipshere mid-latitudes, presented as an original contribution from this study following a novel approach. Both signals, and apparently their constructive superposition, seem to contribute to the organization of the large-scale circulation anomalies leading ultimately to heat waves in CCh. We confirm these results for recent decades (DJF 1981–2020) using temperature observations and further data sets, namely the NCEP-NCAR Reanalysis (NNR) and the Climate Forecast System Reanalysis versions 1 and 2 (CFSR and CFSv2, respectively). Finally, we describe three recent heat wave events in CCh (DJF 2019–2020) to illustrate the suitability of this conceptualization. © 2021 Royal Meteorological Society | |
| Road Traffic Noise on the Santa Marta City Tourist Route | Applied Sciences | Jiménez-Uribe, D.; Daniels, D.; Fleming, Z.; Vélez-Pereira, A. | 2021 | Ciudades Resilientes | 10.3390/app11167196 | https://www.mdpi.com/2076-3417/11/16/7196 | 7196 | Vol: 11 Issue: 16 | 2076-3417 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The objective of this study was to determine the influence of vehicular traffic on the environmental noise levels of the Santa Marta City tourist route on the Colombian coast. An analysis of vehicle types and frequencies at various times of the day over nearly a year helped to track the main sources of environmental noise pollution. Five sampling points were selected, which were distributed over 12 km, with three classified as peripheral urban and two as suburban. The average traffic flow was 966 vehicles/h and was mainly composed of automobiles, with higher values in the peripheral urban area. The noise level was 103.3 dBA, with background and peak levels of 87.2 and 107.3 dBA, respectively. The noise level was higher during the day; however, there were no differences between weekdays and weekends. The results from the analysis of variance showed that the number of vehicles and the noise levels varied greatly according to the time of day and sampling point location. The peak and mean noise levels were correlated with the number of automobiles, buses and heavy vehicles. The mean noise levels were similar at all sample points despite the traffic flow varying, and the background noise was only correlated for automobiles (which varied much more than the heavy vehicles between day and night). |
| La Construcción de la Contaminación Atmosférica como Problema Público, Santiago de Chile (1961-1978) | Historia Ambiental Latinoamericana y Caribeña (HALAC) revista de la Solcha | Labraña, J.; Folchi, M.; Urquiza, A.; Rivas, M. | 2021 | Ciudades Resilientes | 10.32991/2237-2717.2021V11I3.P149-177 | https://www.halacsolcha.org/index.php/halac/article/view/558 | 149-177 | Vol: 11 Issue: 3 | 2237-2717 | Scopus | All Open Access; Gold Open Access | Spanish | La finalidad de esta investigación es analizar los orígenes de la política pública de combate a la contaminación atmosférica en Santiago de Chile y, en particular, el rol que desempeñaron los científicos en este proceso. Para alcanzar este objetivo se examinaron fuentes documentales legislativas, notas del periódico “El Mercurio” y publicaciones científicas entre los años 1961 y 1978, aplicándose un análisis de contenido mixto. Los resultados sugieren que los expertos, haciendo uso de sus redes nacionales e internacionales, fueron capaces de convertir la calidad del aire en un problema de interés nacional que debía resolverse mediante la elaboración de una normativa integral validada por los resultados de la investigación académica y legitimada por una incipiente demanda social en el mismo sentido. Aquello condujo a la conformación de sucesivas comisiones técnico-políticas que asumieron la tarea de comprender el problema de la contaminación atmosférica y proponer medidas para su resolución. A pesar de la promulgación temprana de una legislación específica, la evidencia señala que la complejidad del problema de la contaminación superó la capacidad técnico-política que poseía el Estado para resolver el problema de manera efectiva, el cual se ha extendido hasta el presente. |
| Regional patterns and temporal evolution of ocean iron fertilization and CO2 drawdown during the last glacial termination | Earth and Planetary Science Letters | Lambert, F.; Opazo, N.; Ridgwell, A.; Winckler, G.; Lamy, F.; Shaffer, G.; Kohfeld, K.; Ohgaito, R.; Albani, S.; Abe-Ouchi, A. | 2021 | Ciudades Resilientes | 10.1016/j.epsl.2020.116675 | https://linkinghub.elsevier.com/retrieve/pii/S0012821X20306191 | 116675 | Vol: 554 | 0012821X | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The last time Earth's climate experienced geologically rapid global warming was associated with the last glacial termination, when atmospheric CO2 concentrations rose from 180 ppmv during the Last Glacial Maximum (LGM, 26-19 kaBP) to ∼260 ppmv by the early Holocene (12-8 kaBP). About one quarter of that difference is thought to be due to a stronger biological pump during glacial times, driven by increased aeolian dust deposition and hence greater iron availability in ocean surface waters. However, dust supply did not change uniformly or in synchrony over the deglacial transition and what is not known is the relative importance of different oceanic regions and how this may have changed in time. Using an Earth system model of intermediate complexity, we quantify the sensitivity of atmospheric CO2 to regional changes in iron supply, and test six different global dust reconstructions in order to explore uncertainty in past dust changes. We confirm the Southern Ocean (>34°S) as the region most sensitive to iron fertilization, with the Atlantic and Pacific sectors accounting for about % and %, respectively, of the total CO2 reduction from global iron fertilization. However, the North Pacific contributes % to the total implying an important role for Northern Hemisphere processes in driving deglacial CO2 rise. In addition, our analysis reveals an unexpected regional-temporal disparity, and while Southern Hemisphere iron fertilization influences atmospheric CO2 relatively constantly throughout the termination the impact of the Northern Hemisphere only occurs during the later stages of the termination. |
| Streamflow response to native forest restoration in former Eucalyptus plantations in south central Chile | Hydrological Processes | Lara, A.; Jones, J.; Little, C.; Vergara, N. | 2021 | Cambio de Uso de Suelo | 10.1002/hyp.14270 | https://onlinelibrary.wiley.com/doi/10.1002/hyp.14270 | art: e14270 | Vol: 35 Issue: 8 | 0885-6087, 1099-1085 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Global increases in intensive forestry have raised concerns about forest plantation effects on water, but few studies have tested the effects of plantation forest removal and native forest restoration on catchment hydrology. We describe results of a 14-year paired watershed experiment on ecological restoration in south central Chile which documents streamflow response to the early stages of native forest restoration, after clearcutting of plantations of exotic fast-growing Eucalyptus, planting of native trees, and fostering natural regeneration of native temperate rainforest species. Precipitation, streamflow, and vegetation were measured starting in 2006 in four small (3 to 5 ha) catchments with Eucalyptus globulus plantations and native riparian buffers in the Valdivian Coastal Reserve. Mean annual precipitation is 2500 mm, of which 11% occurs in summer. Streamflow increased, and increases persisted, throughout the first 9 years of vigorous native forest regeneration (2011 to 2019). Annual streamflow increased by 40% to >100% in most years and >150% in fall and summer of some years. Streamflow was 50% to 100% lower than before treatment in two dry summers. Base flow increased by 28% to 87% during the restoration period compared to pre-treatment, and remained elevated in later years despite low summer precipitation. Overall, these findings indicate that removal of Eucalyptus plantations immediately increased streamflow, and native forest restoration gradually restored deep soil moisture reservoirs that sustain base flow during dry periods, increasing water ecosystem services. To our knowledge this is the first study to assess catchment streamflow response to native forest restoration in former forest plantations. Therefore, the results of this study are relevant to global efforts to restore native forest ecosystems on land currently intensively managed with fast-growing forest plantations and may inform policy and decision-making in areas experiencing a drying trend associated with climate change. |
| Valor económico de la conservación de la biodiversidad: el caso del Parque Nacional Yanachaga-Chemillén | Economía Agraria y Recursos Naturales | Lavado-Solis, K.; Orihuela, C.; Vásquez-Lavín, F.; Dávila, J. | 2021 | Cambio de Uso de Suelo | 10.7201/earn.2021.02.05 | https://polipapers.upv.es/index.php/EARN/article/view/earn.2021.02.05 | 101-120 | Vol: 21 Issue: 2 | 2174-7350, 1578-0732 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | The present study determined the willingness to pay for the conservation of the biodiversity (WTP) of the Yanachaga-Chemillén National Park (YChNP), applying the contingent valuation method, in hypothetical scenarios of conserving 6, 9 or 12 species that guaranteed protection of 50 % of the functionality of the ecosystems of this place. It was found that the WTP was determined by the functional characteristics that key species play in the resilience of the PNYCh ecosystems. For this reason, similar studies should evaluate the option of preferring the use of functionality instead of indicators based, for example, on the number of species. |
| Temperature differently affected methanogenic pathways and microbial communities in sub-Antarctic freshwater ecosystems | Environment International | Lavergne, C.; Aguilar-Muñoz, P.; Calle, N.; Thalasso, F.; Astorga-España, M.; Sepulveda-Jauregui, A.; Martinez-Cruz, K.; Gandois, L.; Mansilla, A.; Chamy, R.; Barret, M.; Cabrol, L. | 2021 | Cambio de Uso de Suelo | 10.1016/j.envint.2021.106575 | https://linkinghub.elsevier.com/retrieve/pii/S0160412021002002 | 106575 | Vol: 154 | 01604120 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Freshwater ecosystems are responsible for an important part of the methane (CH4) emissions which are likely to change with global warming. This study aims to evaluate temperature-induced (from 5 to 20 °C) changes on microbial community structure and methanogenic pathways in five sub-Antarctic lake sediments from Magallanes strait to Cape Horn, Chile. We combined in situ CH4 flux measurements, CH4 production rates (MPRs), gene abundance quantification and microbial community structure analysis (metabarcoding of the 16S rRNA gene). Under unamended conditions, a temperature increase of 5 °C doubled MPR while microbial community structure was not affected. Stimulation of methanogenesis by methanogenic precursors as acetate and H2/CO2, resulted in an increase of MPRs up to 127-fold and 19-fold, respectively, as well as an enrichment of mcrA-carriers strikingly stronger under acetate amendment. At low temperatures, H2/CO2-derived MPRs were considerably lower (down to 160-fold lower) than the acetate-derived MPRs, but the contribution of hydrogenotrophic methanogenesis increased with temperature. Temperature dependence of MPRs was significantly higher in incubations spiked with H2/CO2 (c. 1.9 eV) compared to incubations spiked with acetate or unamended (c. 0.8 eV). Temperature was not found to shape the total microbial community structure, that rather exhibited a site-specific variability among the studied lakes. However, the methanogenic archaeal community structure was driven by amended methanogenic precursors with a dominance of Methanobacterium in H2/CO2-based incubations and Methanosarcina in acetate-based incubations. We also suggested the importance of acetogenic H2-production outcompeting hydrogenotrohic methanogenesis especially at low temperatures, further supported by homoacetogen proportion in the microcosm communities. The combination of in situ-, and laboratory-based measurements and molecular approaches indicates that the hydrogenotrophic pathway may become more important with increasing temperatures than the acetoclastic pathway. In a continuously warming environment driven by climate change, such issues are crucial and may receive more attention. |
| Climate and Land Cover Trends Affecting Freshwater Inputs to a Fjord in Northwestern Patagonia | Frontiers in Marine Science | León-Muñoz, J.; Aguayo, R.; Marcé, R.; Catalán, N.; Woelfl, S.; Nimptsch, J.; Arismendi, I.; Contreras, C.; Soto, D.; Miranda, A. | 2021 | Cambio de Uso de Suelo | 10.3389/fmars.2021.628454 | https://www.frontiersin.org/articles/10.3389/fmars.2021.628454/full | 628454 | Vol: 8 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Freshwater inputs strongly influence oceanographic conditions in coastal systems of northwestern Patagonia (41–45°S). Nevertheless, the influence of freshwater on these systems has weakened in recent decades due to a marked decrease in precipitation. Here we evaluate potential influences of climate and land cover trends on the Puelo River (640 m 3 s –1 ), the main source of freshwater input of the Reloncaví Fjord (41.5°S). Water quality was analyzed along the Puelo River basin (six sampling points) and at the discharge site in the Reloncaví Fjord (1, 8, and 25 m depth), through six field campaigns carried out under contrasting streamflow scenarios. We also used several indicators of hydrological alteration, and cross-wavelet transform and coherence analyses to evaluate the association between the Puelo River streamflow and precipitation (1950–2019). Lastly, using the WEAP hydrological model, land cover maps (2001–2016) and burned area reconstructions (1985–2019), we simulated future land cover impacts (2030) on the hydrological processes of the Puelo River. Total Nitrogen and total phosphorus, dissolved carbon, and dissolved iron concentrations measured in the river were 3–15 times lower than those in the fjord. Multivariate analyses showed that streamflow drives the carbon composition in the river. High streamflow conditions contribute with humic and colored materials, while low streamflow conditions corresponded to higher arrival of protein-like materials from the basin. The Puelo River streamflow showed significant trends in magnitude (lower streamflow in summer and autumn), duration (minimum annual streamflow), timing (more floods in spring), and frequency (fewer prolonged floods). The land cover change (LCC) analysis indicated that more than 90% of the basin area maintained its land cover, and that the main changes were attributed to recent large wildfires. Considering these land cover trends, the hydrological simulations project a slight increase in the Puelo River streamflow mainly due to a decrease in evapotranspiration. According to previous simulations, these projections present a direction opposite to the trends forced by climate change. The combined effect of reduction in freshwater input to fiords and potential decline in water quality highlights the need for more robust data and robust analysis of the influence of climate and LCC on this river-fjord complex of northwestern Patagonia. |
| The 2019 Southern Hemisphere Stratospheric Polar Vortex Weakening and Its Impacts | Bulletin of the American Meteorological Society | Lim, E.; Hendon, H.; Butler, A.; Thompson, D.; Lawrence, Z.; Scaife, A.; Shepherd, T.; Polichtchouk, I.; Nakamura, H.; Kobayashi, C.; Comer, R.; Coy, L.; Dowdy, A.; Garreaud, R.; Newman, P.; Wang, G. | 2021 | Agua y Extremos | 10.1175/BAMS-D-20-0112.1 | https://journals.ametsoc.org/view/journals/bams/102/6/BAMS-D-20-0112.1.xml | E1150-E1171 | Vol: 102 Issue: 6 | 0003-0007, 1520-0477 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Abstract This study offers an overview of the low-frequency (i.e., monthly to seasonal) evolution, dynamics, predictability, and surface impacts of a rare Southern Hemisphere (SH) stratospheric warming that occurred in austral spring 2019. Between late August and mid-September 2019, the stratospheric circumpolar westerly jet weakened rapidly, and Antarctic stratospheric temperatures rose dramatically. The deceleration of the vortex at 10 hPa was as drastic as that of the first-ever-observed major sudden stratospheric warming in the SH during 2002, while the mean Antarctic warming over the course of spring 2019 broke the previous record of 2002 by ∼50% in the midstratosphere. This event was preceded by a poleward shift of the SH polar night jet in the uppermost stratosphere in early winter, which was then followed by record-strong planetary wave-1 activity propagating upward from the troposphere in August that acted to dramatically weaken the polar vortex throughout the depth of the stratosphere. The weakened vortex winds and elevated temperatures moved downward to the surface from mid-October to December, promoting a record strong swing of the southern annular mode (SAM) to its negative phase. This record-negative SAM appeared to be a primary driver of the extreme hot and dry conditions over subtropical eastern Australia that accompanied the severe wildfires that occurred in late spring 2019. State-of-the-art dynamical seasonal forecast systems skillfully predicted the significant vortex weakening of spring 2019 and subsequent development of negative SAM from as early as late July. |
| Integridad y multifuncionalidad: un modelo conceptual para hacer efectiva la restauración de los bosques nativos a gran escala | Ciencia & Investigación Forestal | Little, C.; Schlegel, B.; Vergara, G.; González, M. | 2021 | Cambio de Uso de Suelo | 10.52904/0718-4646.2021.545 | https://revista.infor.cl/index.php/infor/article/view/545 | 75-81 | Vol: 27 Issue: 3 | 0718-4646, 0718-4530 | Latindex | Se propone un modelo conceptual con un nuevo enfoque para las iniciativas que apoyen procesos de restauración de los bosques nativos. A partir del establecimiento de un ensayo de restauración a escala operativa, el modelo propone integrar variables de estado de los bosques con sus funciones ecológicas, esto con el objetivo de determinar niveles de integridad que apoyen la definición de los objetivos de la restauración y los indicadores de multifuncionalidad. Asociado al modelo, distinguimos una serie de barreras y oportunidades en los ámbitos ambientales, socio-económicos y de aprendizaje, presentando para cada uno de ellos un conjunto de recomendaciones que puedan aportar a la materialización de nuevas iniciativas de restauración de bosques nativos a gran escala en Chile. Concluimos sobre la importancia de estos nuevos enfoques y la necesidad de incluirlos como acompañamiento a la política pública y las decisiones del sector privado | ||
| Multilevel business power in environmental politics: the avocado boom and water scarcity in Chile | Environmental Politics | Madariaga, A.; Maillet, A.; Rozas, J. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1080/09644016.2021.1892981 | https://www.tandfonline.com/doi/full/10.1080/09644016.2021.1892981 | 1174-1195 | Vol: 30 Issue: 7 | 0964-4016, 1743-8934 | Thomson Reuters ISI (SSCI) | English | The production and export of avocados in Chile have experienced explosive growth since the 1990s, severely threatening local communities’ human right to water. Despite contentious activities and protest, there has been scant reaction from public authorities and policy continues to strongly support avocado exports. We explain this by analyzing the role that business plays in water politics and the different means it has to counter the search for political influence by aggrieved communities. We argue that the outcome is a product of the multilevel deployment of business power. Based on quantitative and qualitative data, we use process tracing methods to unveil business power mechanisms at the local, national and international levels and their connections. We contribute to the cross-fertilization of business power analyses in comparative political economy and environmental politics, and to the understanding of the under-researched multilevel dynamics of business power and the related politics of scale shift. | |
| Conflicto, territorio y extractivismo en Chile. Aportes y límites de la producción académica reciente | Revista de geografía Norte Grande | Maillet, A.; Allain, M.; Delamaza, G.; Irarrazabal, F.; Rivas, R.; Stamm, C.; Viveros, K.; Maillet, A.; Allain, M.; Delamaza, G.; Irarrazabal, F.; Rivas, R.; Stamm, C.; Viveros, K. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.4067/S0718-34022021000300059 | http://www.scielo.cl/scielo.php?script=sci_abstract&pid=S0718-34022021000300059&lng=es&nrm=iso&tlng=es | 59-80 | Vol: 2021 Issue: 80 | 0718-3402 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | Spanish | Resumen:El presente artículo analiza la producción académica que aborda la problemática articu lada por los conceptos de conflicto, territorio y extractivismo en Chile. El análisis de 32 artículos publicados en revistas indexadas entre 2015 y 2020 da cuenta de una preocupa ción importante por el fenómeno. Caracterizamos esta etapa de la literatura en relación al tratamiento de los distintos conceptos, así como de los métodos utilizados, los actores estudiados y las escalas consideradas. Esta producción académica aparece marcada por una rutinización, tanto en su despliegue conceptual, como en la predominancia de los estudios de caso. Para mantener el dinamismo de este campo de investigación, invita mos a complejizar la conceptualización de esta triada, diversificar los métodos y ampliar los actuales objetos de investigación.Palabras clave: conflictos; territorio; extractivismo; escalas; Chile |
| Global resilience models and territories of the South. A critical review | International Journal of Disaster Risk Reduction | Marin, J. | 2021 | Ciudades Resilientes | 10.1016/j.ijdrr.2021.102541 | https://linkinghub.elsevier.com/retrieve/pii/S2212420921005021 | 102541 | Vol: 66 | 22124209 | Thomson Reuters ISI (SCIE) | English | The resilience of cities, regions and other territorial scales is defined by various conceptual frameworks and has since the 2000s constituted a growing scientific and technical field. Although literature points out the difficulty of implementing such a vague and ambiguous concept, a range of metrics, methodological frameworks and principles have emerged, using tools like composite indicators, qualitative assessment or stochastic modelling. Among these models some have been applied globally over the last ten years, for e.g. the City Resilience Framework developed for the 100 Resilient Cities network. This article proposes a discussion of these global resilience models in order to contribute to our understanding of how they are constructed, how they function, and their potential to transform territories. By using literature review and qualitative content analysis, four axes of inquiry are developed: translations and adaptations of the notion of resilience within hegemonic networks; socio-technical markers of resilience models; resilience as a device of neoliberal governmentality; the position of Latin America within the production of knowledge concerning resilience. This manuscript main contribution is to put into question some gaps or biases in our scientific outputs and models that we might be reproducing or legitimating, and that are worth cross-examine. Three key findings are: Evidenced biases in disciplinary associations of resilience; Evidenced gaps in using closed-form of modelling resilience that invisibilize important assumptions of territories and despolitize the concept; The North-South divide resilience knowledge production is not only quantitative but also expressed in the core of models and tools. | |
| Territorialization of the REDD + strategy in the Bribri indigenous people, Talamanca, Costa Rica | Ambiente & Sociedade | Marín-Herrera, M.; Correa-Correa, H.; Blanco-Wells, G. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1590/1809-4422asoc20180231r2vu2021l1ao | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1414-753X2021000100307&tlng=en | e02312 | Vol: 24 | 1809-4422, 1414-753X | SciELO | Abstract This article explores how the attempt of implementing REDD+ affects the livelihoods and nature valuation of the Bribri indigenous people in Talamanca, Costa Rica. The analysis is done using a case study, discourse analysis and collective hermeneutics in documents and interviews produced by international, national, and local social actors. Controversies in the REDD+ strategy have been manifested in the initiative’s de/re/territorialization processes. These processes are legitimized by technocratic discursive strategies associated with climate change mitigation, produced in multilateral negotiations, and adapted by national institutions for purposes not aligned with the interests of the communities. It is concluded that the implementation of REDD + in indigenous territories in Costa Rica gives way to i) the commoditization of nature, participation and traditional forms of governance; ii) the consolidation of a climate eco-governmentality based on the fragmentation of nature; iii) building representations of vulnerable and impoverished indigenous people, and thus justifying intervention in their territories. , Resumo Neste artigo, são explorados os efeitos nos meios de vida e a avaliação da natureza do povo bribri em Talamanca, Costa Rica, contra a tentativa de implementar REDD + nos seus territórios. Por meio de estudo de caso, análise de discurso e hermenêutica coletiva sobre documentos e entrevistas produzidos por atores sociais internacionais, nacionais e locais, controvérsias manifestas são identificadas através de processos de des/re/territorialização da iniciativa. Esses processos são legitimados por estratégias discursivas tecnocráticas associadas à mitigação das mudanças climáticas, produzidas em espaços multilaterais de negociação e adaptadas pelas instituições nacionais para fins não alinhados aos interesses das comunidades. Conclui-se que a implementação de REDD + em terras indígenas na Costa Rica permite: i) mercantilizar a natureza, a participação e as formas tradicionais de governança; ii) consolidar eco-governabilidade climática centrada fragmentação da natureza; iii) construir representações indígenas vulneráveis e empobrecidas, para justificar a intervenção nos seus territórios. , Resumen Se exploran los efectos en los modos de vida y valoración de la naturaleza del pueblo indígena bribri en Talamanca, Costa Rica, ante el intento de implementar REDD+ en sus territorios. Mediante estudio de caso, análisis de discurso y hermenéutica colectiva sobre documentos y entrevistas producidos por actores sociales internacionales, nacionales y locales, se identifican controversias manifiestas a través de procesos de des/re/territorialización de la iniciativa. Estos procesos son legitimados por estrategias discursivas tecnocráticas asociadas a la mitigación del cambio climático, producidos en espacios de negociación multilateral, y adaptados por instituciones nacionales a propósitos no alineados con intereses de las comunidades. Se concluye que la implementación de REDD+ en Costa Rica posibilita i) mercantilizar la naturaleza, la participación y las formas de gobernanza tradicionales; ii) consolidar una eco-gubernamentalidad climática centrada en la fragmentación de la naturaleza; iii) construir representaciones sobre indígenas vulnerados y empobrecidos, para justificar la intervención en sus territorios. |
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| Tree growth decline as a response to projected climate change in the 21st century in Mediterranean mountain forests of Chile | Global and Planetary Change | Matskovsky, V.; Venegas-González, A.; Garreaud, R.; Roig, F.; Gutiérrez, A.; Muñoz, A.; Le Quesne, C.; Klock, K.; Canales, C. | 2021 | Agua y Extremos | 10.1016/j.gloplacha.2020.103406 | https://www.sciencedirect.com/science/article/abs/pii/S0921818120302976 | 13 | Vol: 198 | 0921-8181 | Thomson Reuters ISI (SCIE) | English | Global Climate Models project that observed climate trends are likely to be preserved and the number of extreme events will be increasing during the rest of the 21st century, which may have a detrimental impact on forest ecosystems. These impacts may include forest decline and widespread dieback of the most vulnerable biomes, such as the Mediterranean Forest of Central Chile (MFCC). Nothofagus macrocarpa and Austrocedrus chilensis are two canopy-dominant, endangered tree species in the mountains of MFCC. Here, we project tree growth of these species based on tree-ring width chronologies, a simplified version of a process-based model, and climate change projections. We used the tree ring information derived from ~400 trees from 12 sites distributed across MFCC in combination with the simplified version of process-based Vaganov-Shashkin tree-growth model (VS-Lite) to forecast changes in tree growth for the next four decades. Tree growth projections were made on the basis of monthly values of temperature and precipitation from the output of 35 climate models based on two ensembles of CO2 emission scenarios of the IPCC AR5 (RCP 8.5: higher-emission scenario, and RCP 2.6: lower-emission scenario). For the MFCC region these scenarios result in temperature rise ranging between 0.5 ◦C and 2.0 ◦C, and a precipitation decrease between 5% and 20% by the year 2065, as related to historical conditions. Our results showed that the VS-Lite model is capable of reproducing tree growth decline during the recent extreme dry period, i.e. 2010–2018, which supports its use for tree growth projections in the MFCC region. According to the modeling results, we find that tree growth in both N. macrocarpa and A. chilensis forests distributed in the MFCC region will be adversely affected by future climate changes, mainly starting from the year 2035, under both scenarios. Our work provides evidence of the degree of vulnerability of Mediterranean mountain forests in central Chile according to current climate change projections. The projected decline in tree growth indicates serious risks in the dynamics and survival of these forests relatively soon, so alerts are given about this situation which may require to counteract the deleterious effects of global change on vegetation in this region. | |
| How well do gridded precipitation and actual evapotranspiration products represent the key water balance components in the Nile Basin? | Journal of Hydrology: Regional Studies | McNamara, I.; Baez-Villanueva, O.; Zomorodian, A.; Ayyad, S.; Zambrano-Bigiarini, M.; Zaroug, M.; Mersha, A.; Nauditt, A.; Mbuliro, M.; Wamala, S.; Ribbe, L. | 2021 | Agua y Extremos | 10.1016/j.ejrh.2021.100884 | https://linkinghub.elsevier.com/retrieve/pii/S2214581821001130 | 100884 | Vol: 37 | 22145818 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Study region: Nile Basin, Africa. Study focus: The accurate representation of precipitation (P) and actual evapotranspiration (ETa) patterns is crucial for water resources management, yet there remains a high spatial and temporal variability among gridded products, particularly over data-scarce regions. We evaluated the performance of eleven state-of-the-art P products and seven ETa products over the Nile Basin using a four-step procedure: (i) P products were evaluated at the monthly scale through a point-to-pixel approach; (ii) streamflow was modelled using the Random Forest machine learning technique, and simulated for well-performing catchments for 2009–2018 (to correspond with ETa product availability); (iii) ETa products were evaluated at the multiannual scale using the water balance method; and (iv) the ability of the best-performing P and ETa products to represent monthly variations in terrestrial water storage (ΔTWS) was assessed through a comparison with GRACE Level-3 data. New hydrological insights for the region: CHIRPSv2 was the best-performing P product (median monthly KGE’ of 0.80) and PMLv2 and WaPORv2.1 the best-performing ETa products over the majority of the evaluated catchments. The application of the water balance using these best-performing products captures the seasonality of ΔTWS well over the White Nile Basin, but overestimates seasonality over the Blue Nile Basin. Our study demonstrates how gridded P and ETa products can be evaluated over extremely data-scarce conditions using an easily transferable methodology. |
| Broad-Scale Surface and Atmospheric Conditions during Large Fires in South-Central Chile | Fire | McWethy, D.; Garreaud, R.; Holz, A.; Pederson, G. | 2021 | Agua y Extremos | 10.3390/fire4020028 | https://www.mdpi.com/2571-6255/4/2/28 | 28 | Vol: 4 Issue: 2 | 2571-6255 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The unprecedented size of the 2017 wildfires that burned nearly 600,000 hectares of central Chile highlight a need to better understand the climatic conditions under which large fires develop. Here we evaluate synoptic atmospheric conditions at the surface and free troposphere associated with anomalously high (active) versus low (inactive) months of area burned in south-central Chile (ca. 32–41° S) from the Chilean Forest Service (CONAF) record of area burned from 1984–2018. Active fire months are correlated with warm surface temperatures, dry conditions, and the presence of a circumpolar assemblage of high-pressure systems located ca. 40°–60° S. Additionally, warm surface temperatures associated with active fire months are linked to reduced strength of cool, onshore westerly winds and an increase in warm, downslope Andean Cordillera easterly winds. Episodic warm downslope winds and easterly wind anomalies superimposed on long-term warming and drying trends will continue to create conditions that promote large fires in south-central Chile. Identifying the mechanisms responsible for easterly wind anomalies and determining whether this trend is strengthening due to synoptic-scale climatic changes such as the poleward shift in Southern Hemisphere westerly winds will be critical for anticipating future large fire activity in south-central Chile. |
| Forecasting PM2.5 levels in Santiago de Chile using deep learning neural networks | Urban Climate | Menares, C.; Perez, P.; Parraguez, S.; Fleming, Z. | 2021 | Ciudades Resilientes | 10.1016/j.uclim.2021.100906 | https://linkinghub.elsevier.com/retrieve/pii/S221209552100136X | 100906 | Vol: 38 | 22120955 | Thomson Reuters ISI (SCIE) | English | Air pollution has been shown to have a direct effect on human health. In particular, PM2.5 has been proven to be related to cardiovascular and respiratory problems. Therefore, it is important to have accurate models to predict high pollution events for this and other pollutants. We present different models that forecast PM2.5 maximum concentrations using a Long Short-Term Memory (LSTM) based neural network and a Deep Feedforward Neural Network (DFFNN). Ten years of air pollution and meteorological measurements from the network of monitoring stations in the city of Santiago, Chile were used, focusing on the behaviour of three zones of the city. All missing values were rebuilt using a method based on discrete cosine transforms and photochemical predictors selected through unsupervised clustering. Deep learning techniques provide significant improvements compared to a traditional multi-layer neural networks, particularly the LSTM model configured with a 7-day memory window (synoptic scale of pollution patterns) can capture critical pollution events at sites with both primary and secondary air pollution problems. Furthermore, the LSTM model consistently outperform deterministic models currently used in Santiago, Chile. | |
| How Much Can We See from a UAV-Mounted Regular Camera? Remote Sensing-Based Estimation of Forest Attributes in South American Native Forests | Remote Sensing | Miranda, A.; Catalán, G.; Altamirano, A.; Zamorano-Elgueta, C.; Cavieres, M.; Guerra, J.; Mola-Yudego, B. | 2021 | Cambio de Uso de Suelo | 10.3390/rs13112151 | https://www.mdpi.com/2072-4292/13/11/2151 | 2151 | Vol: 13 Issue: 11 | 2072-4292 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Data collection from large areas of native forests poses a challenge. The present study aims at assessing the use of UAV for forest inventory on native forests in Southern Chile, and seeks to retrieve both stand and tree level attributes from forest canopy data. Data were collected from 14 plots (45 × 45 m) established at four locations representing unmanaged Chilean temperate forests: seven plots on secondary forests and seven plots on old-growth forests, including a total of 17 different native species. The imagery was captured using a fixed-wing airframe equipped with a regular RGB camera. We used the structure from motion and digital aerial photogrammetry techniques for data processing and combined machine learning methods based on boosted regression trees and mixed models. In total, 2136 trees were measured on the ground, from which 858 trees were visualized from the UAV imagery of the canopy, ranging from 26% to 88% of the measured trees in the field (mean = 45.7%, SD = 17.3), which represented between 70.6% and 96% of the total basal area of the plots (mean = 80.28%, SD = 7.7). Individual-tree diameter models based on remote sensing data were constructed with R2 = 0.85 and R2 = 0.66 based on BRT and mixed models, respectively. We found a strong relationship between canopy and ground data; however, we suggest that the best alternative was combining the use of both field-based and remotely sensed methods to achieve high accuracy estimations, particularly in complex structure forests (e.g., old-growth forests). Field inventories and UAV surveys provide accurate information at local scales and allow validation of large-scale applications of satellite imagery. Finally, in the future, increasing the accuracy of aerial surveys and monitoring is necessary to advance the development of local and regional allometric crown and DBH equations at the species level. |
| Sentencia de la Corte Suprema dictada en causa “Gallardo con Anglo American Sur S.A.”, Rol N°72.198-2020, de 18 de enero de 2021: Reconocimiento del Derecho Humano al Agua. | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Cornejo, C. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/en/jurisprudencia-al-dia-chile-derecho-humano-al-agua/ | 1989-5666 | Thomson Reuters ISI (ESCI) | ||||||
| Sentencia de la Corte Suprema dictada en causa “Jara Alarcón, Luis con Servicio de Evaluación Ambiental”, Rol N°8573-2019, de 13 de enero de 2021 | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Cornejo, C. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/en/jurisprudencia-al-dia-chile-participacion-evaluacion-ambiental/ | 1989-5666 | Thomson Reuters ISI (ESCI) | ||||||
| Principio precautorio, sustentabilidad y mejor información técnica disponible como criterios de actuación legítima. Comentario a la sentencia de la Corte Suprema en causa “Guarache Gómez con Subsecretaría de Pesca y Acuicultura”, Rol N°71.883-2020, de 1 de abril de 2021 | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Cornejo, C. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/en/jurisprudencia-al-dia-chile-principio-de-precaucion-pesca-desarrollo-sostenible/ | 1989-5666 | Thomson Reuters ISI (ESCI) | ||||||
| Transición justa en la mitigación al Cambio Climático. Comentario a la sentencia de la Corte Suprema en recurso de protección rol N°25.530-2021, de 9 de agosto de 2021 | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Cornejo, C. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/en/jurisprudencia-al-dia-chile-transicion-energetica-cambio-climatico/ | 1989-5666 | Thomson Reuters ISI (ESCI) | ||||||
| Estado ambiental de derecho y naturaleza constitucional de los principios preventivo, precautorio, responsabilidad y justicia ambiental. Comentario a la sentencia de inaplicabilidad por inconstitucional rol N°9418-2020, de 15 de junio de 2021, del Tribunal Constitucional chileno | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Cornejo, C. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/en/jurisprudencia-al-dia-chile-residuos-salud/ | 1989-5666 | Thomson Reuters ISI (ESCI) | ||||||
| Sentencia del Segundo Tribunal Ambiental dictada en causa “Oceana INC. / Ministerio de Economía, Fomento y Turismo (Res. Exenta N°11 de fecha 12 de febrero de 2020)”, Rol N°237-2020, de 13 de mayo de 2021: Deja sin efecto aumento de cuota de sobrepesca de merluza austral | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Illanes, J. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/en/jurisprudencia-al-dia-chile-pesca/ | 1989-5666 | Thomson Reuters ISI (ESCI) | ||||||
| Sentencia de la Corte Suprema dictada en causa “Instituto Nacional de Derechos Humanos/ Gobernación Provincial de Petorca”, Rol N°131.140-2020, de 23 de marzo de 2021: Reconocimiento del Derecho Humano al Agua | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Illanes, J. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/en/jurisprudencia-al-dia-chile-derecho-humano-al-agua-2/ | 1989-5666 | Thomson Reuters ISI (ESCI) | ||||||
| Sentencia Rol 210-2019 del Segundo Tribunal Ambiental, caratulado “Alonso Raggio, Katta Beatriz y otros en contra del Ministerio del Medio Ambiente” | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer, K. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/en/jurisprudencia-al-dia-chile-descontaminacion-atmosferica-principio-quien-contamina-paga/ | 1989-5666 | Thomson Reuters ISI (ESCI) | ||||||
| Encuesta sobre percepciones de la ciudadanía de Punta Arenas sobre cambio climático, gobernanza climática y aspectos constitucionales. | Moraga, P.; Sapiain, R.; Aldunce, P.; Urquiza, A.; Rojas, M.; Medina, L.; Valenzuela, C.; Cornejo, C. | 2021 | Agua y Extremos; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://bit.ly/3pxYatd | Entre agosto 202 y septiembre 2021, un equipo interdisciplinario de la Universidad de Chile, del Centro de Ciencia del Clima y la Resiliencia (CR)2 y con el apoyo del Centro de Investigación GAIA Antártica (CIGA) de la Universidad de Magallanes, desarrolló el proyecto "Laboratorio social para la cosntrucción comunitaria de bases constitucionales para una sociedad resiliente al cambio climático, una perspectiva desde la Patagonia". | ||||||||
| La ciudad del mañana en la nueva constitución: Una mirada desde la Patagonia | Moraga, P.; Sapiains A., R.; Rojas, M.; Medina, L.; Valenzuela, C.; Cornejo, C.; Pulgar, A.; Aldunce, P.; Urquiza, A.; Azócar, G.; Sepúlveda, B. | 2021 | Agua y Extremos; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://www.cr2.cl/la-ciudad-del-manana-en-la-nueva-constitucion-una-mirada-desde-la-patagonia/ | Entre agosto 202 y septiembre 2021, un equipo interdisciplinario de la Universidad de Chile, del Centro de Ciencia del Clima y la Resiliencia (CR)2 y con el apoyo del Centro de Investigación GAIA Antártica (CIGA) de la Universidad de Magallanes, desarrolló el proyecto "Laboratorio social para la cosntrucción comunitaria de bases constitucionales para una sociedad resiliente al cambio climático, una perspectiva desde la Patagonia". | ||||||||
| Handbook of Interdisciplinarity | Morales, B.; Muñoz, C. | 2021 | Gobernanza e Interfaz Ciencia y Política; Transversal | https://bit.ly/3scg8U0 | The current ways that science is structured, and its results evaluated are intersected by the complexity of the challenges facing our society. Complex or ‘wicked’ problems, such as those generally known as ‘development issues’ (such as inequity, overextraction of natural resources and the impacts of climate change), have prompted the scientific community to revisit and transform the boundaries of their disciplines and move towards questions, methodologies and approaches that are increasingly integrated and based upon the society’s needs (Hessels & Van Lente, 2008). The complexity of present-day problems thus presents new scientific challenges and demands changes in the process of knowledge construction. This translates into new scientific approaches that, among other challenges, seek to go beyond conventional disciplinary and institutional structures of knowledge generation (Stanley et al., 1988; Allmendinger, 2015; Urquiza et al., 2018). |
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| Manual de Interdisciplina | Morales, B.; Muñoz, C. | 2021 | Gobernanza e Interfaz Ciencia y Política; Transversal | https://bit.ly/3scg8U0 | Las formas en que está estructurada la ciencia y se evalúan sus resultados hoy en día están cruzadas por la complejidad de los desafíos y necesidades que enfrenta la sociedad actual. Problemas complejos como los globalmente catalogados “problemas de desarrollo” (tales como la inequidad, la explotación de recursos naturales o los impactos del cambio climático), han obligado a la comunidad científica a revisitar y transformar sus límites disciplinares, y avanzar hacia preguntas, metodologías y enfoques cada vez más integrados (Hessels y Van Lente, 2008), que permitan generar una evidencia científica robusta. La complejidad de los problemas actuales impone así nuevos desafíos científicos y demanda cambios en el proceso de construcción del conocimiento. Lo anterior se traduce en nuevos abordajes científicos que, entre otros desafíos, proponen sobrepasar las estructuras disciplinares e institucionales convencionales de generación de conocimiento (Frank et al., 1988; Allmendinger, 2015; Urquiza et al., 2018). |
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| The state of science on severe air pollution episodes: Quantitative and qualitative analysis | Environment International | Morawska, L.; Zhu, T.; Liu, N.; Amouei Torkmahalleh, M.; de Fatima Andrade, M.; Barratt, B.; Broomandi, P.; Buonanno, G.; Carlos Belalcazar Ceron, L.; Chen, J.; Cheng, Y.; Evans, G.; Gavidia, M.; Guo, H.; Hanigan, I.; Hu, M.; Jeong, C.; Kelly, F.; Gallardo, L.; Kumar, P.; Lyu, X.; Mullins, B.; Nords... | 2021 | Ciudades Resilientes | 10.1016/j.envint.2021.106732 | https://linkinghub.elsevier.com/retrieve/pii/S0160412021003573 | 106732 | Vol: 156 | 01604120 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Severe episodic air pollution blankets entire cities and regions and have a profound impact on humans and their activities. We compiled daily fine particle (PM2.5) data from 100 cities in five continents, investigated the trends of number, frequency, and duration of pollution episodes, and compared these with the baseline trend in air pollution. We showed that the factors contributing to these events are complex; however, long-term measures to abate emissions from all anthropogenic sources at all times is also the most efficient way to reduce the occurrence of severe air pollution events. In the short term, accurate forecasting systems of such events based on the meteorological conditions favouring their occurrence, together with effective emergency mitigation of anthropogenic sources, may lessen their magnitude and/or duration. However, there is no clear way of preventing events caused by natural sources affected by climate change, such as wildfires and desert dust outbreaks. |
| An early Holocene westerly minimum in the southern mid-latitudes | Quaternary Science Reviews | Moreno, P.; Henríquez, W.; Pesce, O.; Henríquez, C.; Fletcher, M.; Garreaud, R.; Villa-Martínez, R. | 2021 | Agua y Extremos | 10.1016/j.quascirev.2020.106730 | https://linkinghub.elsevier.com/retrieve/pii/S0277379120306922 | 106730 | Vol: 251 Issue: 1 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | An important coupled ocean-atmospheric system in the mid- and high latitudes involves the Southern Westerly Winds (SWW) and the Southern Ocean (SO), which controls climate in the southernmost third of the world, deep water formation, and ventilation of CO2 from the deep ocean. Most studies have examined its role as a driver of atmospheric CO2 concentrations during glacial terminations, but very few have investigated its influence during the Holocene, i.e. the current interglacial. A fundamental problem, however, is resolving whether the SWW strength increased or declined during the early Holocene (∼11.5–7.5 ka, ka = 1000 cal yr BP) in sectors adjacent to the Drake Passage. Here we assess past changes in SWW influence over the last ∼17,000 years using terrestrial paleoclimate records from southwestern Patagonia (∼52°S). We detect a zonally symmetric Early Holocene Westerly Minimum which diminished wind stress and upwelling on the SO, contributing to a contemporary decline in atmospheric CO2 concentrations and enrichment in the stable carbon isotope ratio of atmospheric CO2 (δ13Catm). Our mid-latitude data also indicate a shift to strong SWW influence at ∼7.5 ka which correlates with a sustained increase in atmospheric CO2 and halt in the δ13Catm rise, suggesting enhancement of high-latitude ocean ventilation by an invigorated SWW-SO coupled system. | |
| Vegetation, disturbance, and climate history since the onset of ice-free conditions in the Lago Rosselot sector of Chiloé continental (44°S), northwestern Patagonia | Quaternary Science Reviews | Moreno, P.; Videla, J.; Kaffman, M.; Henríquez, C.; Sagredo, E.; Jara-Arancio, P.; Alloway, B. | 2021 | Agua y Extremos | 10.1016/j.quascirev.2021.106924 | https://linkinghub.elsevier.com/retrieve/pii/S0277379121001311 | 106924 | Vol: 260 | 02773791 | Thomson Reuters ISI (SCIE) | English | We present results from Lago Negro, a small closed-basin lake adjacent to Lago Rosselot, to examine the vegetation and environmental history of an insufficiently studied sector of Chiloé Continental (41°30′-44°S) in northwestern Patagonia. Lake sediment cores from Lago Negro reveal 27 tephra deposited since ∼12.7 ka, including two prominent rhyodacite tephra marker beds erupted from Volcán Melimoyu, and a stratified basal clastic unit we attribute to meltwater discharge from an ice tongue that originated from Monte Queulat and covered Lago Rosselot during its expanded position, presumably Antarctic Cold Reversal in age. The pollen record shows closed-canopy North Patagonian rainforests since ∼12.7 ka, with variations in species composition and structure that suggest dynamic responses of the vegetation to past environmental changes. Vegetation responses to climate in the Lago Negro record were modulated, sometimes interrupted, by high magnitude and frequent disturbance regimes, most notably during maxima in explosive volcanic activity (∼9.5–7.2 ka and ∼3.6–1.6 ka) and heightened fire activity. Since Lago Negro is the southernmost palynological site so far investigated in the region and is located within a volcanically active sector, it provides a valuable perspective for assessing past vegetation responses along environmental gradients since the last glaciation. When compared with other sites throughout northwestern Patagonia, our record reveals a distinct north-to-south gradient in temperature and precipitation, with peak temperature and rainfall seasonality in the north, and a west-to-east gradient in disturbance regimes, with maximum frequency and magnitude of explosive volcanic events in the east. These gradients have modulated the response of rainforest vegetation to climate forcing at regional scale since ∼12.7 ka. We identify negligible differences in timing for the majority of key vegetation signals during the initial phase of the Lago Negro record, and propose that plant colonization and expansion along the ∼360 km long corridor through the Pacific slope of the northwestern Patagonian Andes was a rapid process during the Last Glacial Termination. |
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| Local and global environmental drivers of growth chronologies in a demersal fish in the south-eastern Pacific Ocean | Ecological Indicators | Moyano, G.; Plaza, G.; Cerna, F.; Muñoz, A. | 2021 | Agua y Extremos | 10.1016/j.ecolind.2021.108151 | https://linkinghub.elsevier.com/retrieve/pii/S1470160X21008165 | 108151 | Vol: 131 | 1470-160X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Upwelling and the El Niño “Southern Oscillation” (ENSO) are recurrent climatic phenomena in the southeastern Pacific Ocean that severely affect the reproduction and growth of pelagic fish populations. However, there are not long-term growth data from demersal fish populations to test these interconections in a long-term analysis. For this reason, a first extensive growth chronology was reconstructed from the annual growth of sagittal otoliths as a proxy for somatic growth for the cardinalfish (Epigonus crassicaudus). Adult fish ranging from 35 to 40 cm in fork length and from 39 to 63 years in age were collected off Chilean waters. The master chronologies were estimated for the period from 1974 to 2014, using the regional curve standardization approach (RCS) and linear mixed models (LMMs). Growth indexes derived from both approaches followed a similar trend and were positively correlated with the Humboldt Current Index (HCI) and negatively with ENSO, Pacific Decadal Oscillation and sea surface temperature. LMMs showed that a 75% of growth variability was explained by the age of increment formation and HCI was the environmental index that most significantly affected the annual growth of cardinalfish followed by the sea surface temperature in spring. A reduced growth phase from 1974 to 1996 contrasted with a higher growth period from 1997, matching the 1997/1998 climatic regime shift, demonstrating that the enhanced growth for cardinalfish was associated with upwelling of nutrient rich water to the surface, triggering an increase of the primary and secondary productivity during the prevalence of a cold regime period in the Humboldt Current System. The consistence between RCS and LMM methods was indicative that both approaches are promising to evaluate the influence of environmental drivers on the growth condition of a demersal fish population in a highly productive marine ecosystem. © 2021 The Author(s) |
| Reduced Complexity Model Intercomparison Project Phase 2: Synthesizing Earth System Knowledge for Probabilistic Climate Projections | Earth's Future | Nicholls, Z.; Meinshausen, M.; Lewis, J.; Corradi, M.; Dorheim, K.; Gasser, T.; Gieseke, R.; Hope, A.; Leach, N.; McBride, L.; Quilcaille, Y.; Rogelj, J.; Salawitch, R.; Samset, B.; Sandstad, M.; Shiklomanov, A.; Skeie, R.; Smith, C.; Smith, S.; Su, X.; Tsutsui, J.; Vega-Westhoff, B.; Woodard, D. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1029/2020EF001900 | https://doi.org/10.1029/2020EF001900 | art: e2020EF001900 | Vol: 9 Issue: 6 | 2328-4277 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Over the last decades, climate science has evolved rapidly across multiple expert domains. Our best tools to capture state-of-the-art knowledge in an internally self-consistent modeling framework are the increasingly complex fully coupled Earth System Models (ESMs). However, computational limitations and the structural rigidity of ESMs mean that the full range of uncertainties across multiple domains are difficult to capture with ESMs alone. The tools of choice are instead more computationally efficient reduced complexity models (RCMs), which are structurally flexible and can span the response dynamics across a range of domain-specific models and ESM experiments. Here we present Phase 2 of the Reduced Complexity Model Intercomparison Project (RCMIP Phase 2), the first comprehensive intercomparison of RCMs that are probabilistically calibrated with key benchmark ranges from specialized research communities. Unsurprisingly, but crucially, we find that models which have been constrained to reflect the key benchmarks better reflect the key benchmarks. Under the low-emissions SSP1-1.9 scenario, across the RCMs, median peak warming projections range from 1.3 to 1.7°C (relative to 1850–1900, using an observationally based historical warming estimate of 0.8°C between 1850–1900 and 1995–2014). Further developing methodologies to constrain these projection uncertainties seems paramount given the international community's goal to contain warming to below 1.5°C above preindustrial in the long-term. Our findings suggest that users of RCMs should carefully evaluate their RCM, specifically its skill against key benchmarks and consider the need to include projections benchmarks either from ESM results or other assessments to reduce divergence in future projections. © 2021. The Authors. Earth's Future published by Wiley Periodicals LLC on behalf of American Geophysical Union. |
| La construcción social de los mercados de agua en Chile: Un enfoque desde la geografía legal | Revista de geografía Norte Grande | Nicolas-Artero, C. | 2021 | Agua y Extremos | 10.4067/S0718-34022021000200163 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-34022021000200163&lng=en&nrm=iso&tlng=en | 163-182 | Vol: 2021 Issue: 79 | 0718-3402 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access; Green Open Access | English | The article proposes an approach from the legal geography to understand the social construction of water markets in the semi-arid basin of the Elqui river, from the second half of the 20th century. Using qualitative methodologies (ethnography, interviews, archives), it reveals the jointly spatial and legal dimension of the formation of water markets. The technical water objects installed since the second half of the 20th century attract new investors and transform the political economy of the valley. Since then, the users have used technical water objects and have instrumentalized or produced law locally to buy, sell or rent water rights, forming five water markets. |
| Questionner la relation société – environnement en Amérique latine : extractivisme, violences et résistances: | L'Information géographique | Nicolas-Artero, C. | 2021 | 10.3917/lig.854.0093 | https://www.cairn.info/revue-l-information-geographique-2021-4-page-93.htm?ref=doi | 93-111 | Vol: Vol. 85 Issue: 4 | 0020-0093 | Thomson Reuters ISI (ESCI) | ||||
| Apropiación del agua y producción del espacio. La dimensión espacial del derecho de aguas en el Valle del Elqui (Chile) | Quid16. Revista del Área de Estudios Urbanos. | Nicolas-Artero, C. | 2021 | https://publicaciones.sociales.uba.ar/index.php/quid16/article/view/7141 | 264-267 | Vol: 16 | 2250-4060 | Erih, Latindex | Desde la geografía ambiental y jurídica, esta tesis de doctorado da cuenta de las relaciones entre la apropiación del agua y la producción del espacio. Este enfoque permite analizar la dimensión espacial del derecho de aguas. El aporte conceptual de la tesis reside en proponer la noción de sistema geolegal fluvial para estudiar, desde una perspectiva multiescalar y diacrónica, las relaciones de poder que se dan en la definición de las normas jurídicas de reparto, distribución y administración del agua. La investigación emplea una metodología cualitativa (etnografía, entrevistas semi-estructuradas, consulta de archivos) y el uso de datos cuantitativos. Las entrevistas se realizaron a múltiples actores: representantes de autoridades e instituciones estatales, empresarios y asociaciones gremiales, organizaciones de regantes y habitantes. | ||||
| Introducción. Disputada, apropiada y desposeída: la naturaleza en las ciudades latinoamericanas | Cahiers des Amériques latines | Nicolas-Artero, C.; Fuster-Farfán, X.; Velut, S. | 2021 | Agua y Extremos | 10.4000/cal.13089 | http://journals.openedition.org/cal/13089 | 1-13 | Issue: 97 | 1141-7161, 2268-4247 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | Spanish | |
| Introduction. Contestée, appropriée et dépossédée : la place de la nature dans les villes latino-américaines | Cahiers des Amériques latines | Nicolas-Artero, C.; Fuster-Farfán, X.; Velut, S. | 2021 | Agua y Extremos | 10.4000/cal.13080 | http://journals.openedition.org/cal/13080 | 23-35 | Issue: 97 | 1141-7161, 2268-4247 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | French | |
| Effective targeting and additionality. Evaluating the D.L. 701 reforms for afforesting erodible land in Southern Chile | Land Economics | Niklitschek, M.; Labbé, R.; Alzamora, R.; Vásquez, F. | 2021 | Cambio de Uso de Suelo | 10.3368/le.97.4.011520-0003R2 | http://le.uwpress.org/lookup/doi/10.3368/le.97.4.011520-0003R2 | 745-767 | Vol: 97 Issue: 4 | 0023-7639, 1543-8325 | Thomson Reuters ISI (SSCI) | English | We analyze the targeting and additionality of the Chilean afforestation program reforms implemented in the mid-1990s. Propensity score matching (PSM) estimates are obtained by potential erosion categories using random area sample data. The additional afforestation percentage is estimated to be larger for none or low and very severe categories of potential erosion parcels. Even though the program helped maintain forest cover to highly erodible land, afforested parcels with high opportunity cost and possible negative amenity benefits are also attributed to the program. To improve the cost-effectiveness and to avoid misallocation of land and water resources, more effective targeting is required. | |
| Validation of 4D Flow based relative pressure maps in aortic flows | Medical Image Analysis | Nolte, D.; Urbina, J.; Sotelo, J.; Sok, L.; Montalba, C.; Valverde, I.; Osses, A.; Uribe, S.; Bertoglio, C. | 2021 | Ciudades Resilientes | 10.1016/j.media.2021.102195 | https://linkinghub.elsevier.com/retrieve/pii/S1361841521002401 | 102195 | Vol: 74 | 13618415 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | While the clinical gold standard for pressure difference measurements is invasive catheterization, 4D Flow MRI is a promising tool for enabling a non-invasive quantification, by linking highly spatially resolved velocity measurements with pressure differences via the incompressible Navier–Stokes equations. In this work we provide a validation and comparison with phantom and clinical patient data of pressure difference maps estimators. We compare the classical Pressure Poisson Estimator (PPE) and the new Stokes Estimator (STE) against catheter pressure measurements under a variety of stenosis severities and flow intensities. Specifically, we use several 4D Flow data sets of realistic aortic phantoms with different anatomic and hemodynamic severities and two patients with aortic coarctation. The phantom data sets are enriched by subsampling to lower resolutions, modification of the segmentation and addition of synthetic noise, in order to study the sensitivity of the pressure difference estimators to these factors. Overall, the STE method yields more accurate results than the PPE method compared to catheterization data. The superiority of the STE becomes more evident at increasing Reynolds numbers with a better capacity of capturing pressure gradients in strongly convective flow regimes. The results indicate an improved robustness of the STE method with respect to variation in lumen segmentation. However, with heuristic removal of the wall-voxels, the PPE can reach a comparable accuracy for lower Reynolds’ numbers. |
| Deep fire topology: Understanding the role of landscape spatial patterns in wildfire occurrence using artificial intelligence | Environmental Modelling & Software | Pais, C.; Miranda, A.; Carrasco, J.; Shen, Z. | 2021 | Cambio de Uso de Suelo | 10.1016/j.envsoft.2021.105122 | https://linkinghub.elsevier.com/retrieve/pii/S1364815221001651 | 105122 | Vol: 143 | 13648152 | Thomson Reuters ISI (SCIE) | English | Increasing wildfire activity globally has become an urgent issue with enormous ecological and social impacts. In this work, we focus on analyzing and quantifying the influence of landscape topology, understood as the spatial structure and interaction of multiple land-covers in an area, on fire ignition. We propose a deep learning framework, Deep Fire Topology, to estimate and predict wildfire ignition risk. We focus on understanding the impact of these topological attributes and the rationale behind the results to provide interpretable knowledge for territorial planning considering wildfire ignition uncertainty. We demonstrate the high performance and interpretability of the framework in a case study, accurately detecting risky areas by exploiting spatial patterns. This work reveals the strong potential of landscape topology in wildfire occurrence prediction and its implications to develop robust landscape management plans. We discuss potential extensions and applications of the proposed method, available as an open-source software. | |
| Comité Científico de Cambio Climático: The Chilean Potential for Exporting Renewable Energy (Mitigation and Energy Working Group Report) | Palma-Behnke, R.; Rojas, M.; Abarca del Río, R.; Amaya, J. | 2021 | Gobernanza e Interfaz Ciencia y Política | https://comitecientifico.minciencia.gob.cl/wp-content/uploads/2021/11/The_Chilean_Potential_for_Exporting_Renewable_Energy_web.pdf | |||||||||
| Biotic and abiotic drivers of carbon, nitrogen and phosphorus stocks in a temperate rainforest | Forest Ecology and Management | Perez-Quezada, J.; Pérez, C.; Brito, C.; Fuentes, J.; Gaxiola, A.; Aguilera-Riquelme, D.; Lopatin, J. | 2021 | Cambio de Uso de Suelo | 10.1016/j.foreco.2021.119341 | https://linkinghub.elsevier.com/retrieve/pii/S0378112721004291 | 119341 | Vol: 494 | 03781127 | Thomson Reuters ISI (SCIE) | English | Forest ecosystems are recognized for their large capacity to store carbon (C) in their aboveground and belowground biomass and soil pools. While the distribution of C among ecosystem pools has been extensively studied, less is known about nitrogen (N) and phosphorus (P) pools and how these stocks relate to each other. There is also a need to understand how biotic and abiotic ecosystem properties drive the magnitude and distribution of C-N-P stocks. We studied a temperate rainforest in southern South America to answer the following questions: 1) how are C-N-P total stocks distributed among the different ecosystem pools?, 2) how do C:N, C:P and N:P ratios vary among ecosystem pools?, and 3) which are the main biotic and abiotic drivers of C-N-P stocks? We established 33 circular plots to estimate C, N, and P stocks in different pools (i.e. trees, epiphytes, understory, necromass, leaf litter, and soil) and a set of biotic (e.g., tree density and richness) and abiotic variables (e.g., air temperature, humidity and soil depth). We used structural equation modeling to identify the relative importance of environmental drivers on C-N-P stocks. We found that total ecosystem stocks (mean ± SE) were 1062 ± 58 Mg C ha−1, 28.8 ± 1.5 Mg N ha−1, and 347 ± 12.5 kg P ha−1. The soil was the largest ecosystem pool, containing 68%, 92%, and 73% of the total C, N, and P stocks, respectively. Compared to representative temperate forests, the soil of this forest contains the largest concentrations and stocks of C and N. The low P stock and wide soil C:P and N:P ratios suggest that P may be limiting forest productivity. The ecosystem C-N-P stocks were mainly driven by abiotic properties measured in the study area, however for N stocks, variables such as plant diversity and canopy openness were also relevant. Our results provide evidence about the importance not only of understanding the differences in C, N, and P stocks but also of the factors that drive such differences. This is key to inform conservation policies related to preserving old-growth forests in southern South America, which indeed are facing a rapid land-use change process. | |
| Contaminant emissions as indicators of chemical elements in the snow along a latitudinal gradient in southern Andes | Scientific Reports | Pizarro, J.; Vergara, P.; Cerda, S.; Cordero, R.; Castillo, X.; Rowe, P.; Casassa, G.; Carrasco, J.; Damiani, A.; Llanillo, P.; Lambert, F.; Rondanelli, R.; Huneeus, N.; Fernandoy, F.; Alfonso, J.; Neshyba, S. | 2021 | Zonas Costeras | 10.1038/s41598-021-93895-1 | http://www.nature.com/articles/s41598-021-93895-1 | 14530 | Vol: 11 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The chemical composition of snow provides insights on atmospheric transport of anthropogenic contaminants at different spatial scales. In this study, we assess how human activities influence the concentration of elements in the Andean mountain snow along a latitudinal transect throughout Chile. The concentration of seven elements (Al, Cu, Fe, Li, Mg, Mn and Zn) was associated to gaseous and particulate contaminants emitted at different spatial scales. Our results indicate carbon monoxide (CO) averaged at 20 km and nitrogen oxide (NOx) at 40 km as the main indicators of the chemical elements analyzed. CO was found to be a significant predictor of most element concentrations while concentrations of Cu, Mn, Mg and Zn were positively associated to emissions of NOx. Emission of 2.5 μm and 10 μm particulate matter averaged at different spatial scales was positively associated to concentration of Li. Finally, the concentration of Zn was positively associated to volatile organic compounds (VOC) averaged at 40 km around sampling sites. The association between air contaminants and chemical composition of snow suggests that regions with intensive anthropogenic pollution face reduced quality of freshwater originated from glacier and snow melting. |
| Nexus Thinking at River Basin Scale: Food, Water and Welfare | Water | Ponce Oliva, R.; Fernández, F.; Vasquez-Lavín, F.; Arias Montevechio, E.; Julio, N.; Stehr, A. | 2021 | Cambio de Uso de Suelo | 10.3390/w13071000 | https://www.mdpi.com/2073-4441/13/7/1000 | 1000 | Vol: 13 Issue: 7 | 2073-4441 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Water resources face an unparalleled confluence of pressures, with agriculture and urban growth as the most relevant human-related stressors. In this context, methodologies using a Nexus framework seem to be suitable to address these challenges. However, the urban sector has been commonly ignored in the Nexus literature. We propose a Nexus framework approach, considering the economic dimensions of the interdependencies and interconnections among agriculture (food production) and the urban sector as water users within a common basin. Then, we assess the responses of both sectors to climatic and demographic stressors. In this setting, the urban sector is represented through an economic water demand at the household level, from which economic welfare is derived. Our results show that the Nexus components here considered (food, water, and welfare) will be negatively affected under the simulated scenarios. However, when these components are decomposed to their particular elements, we found that the less water-intensive sector—the urban sector—will be better off since food production will leave significant amounts of water available. Moreover, when addressing uncertainty related to climate-induced shocks, we could identify the basin resilience threshold. Our approach shows the compatibilities and divergences between food production and the urban sector under the Nexus framework. |
| Water Use and Climate Stressors in a Multiuser River Basin Setting: Who Benefits from Adaptation? | Water Resources Management | Ponce Oliva, R.; Montevechio, E.; Jorquera, F.; Vásquez-Lavin, F.; Stehr, A. | 2021 | Cambio de Uso de Suelo | 10.1007/s11269-020-02753-8 | http://link.springer.com/10.1007/s11269-020-02753-8 | 897-915 | Vol: 35 Issue: 3 | 0920-4741, 1573-1650 | Thomson Reuters ISI (SCIE) | English | Adapting to new climate conditions will require an intricate mix of knowledge, planning, coordination, and foresight. There is increasing sectoral evidence on the implementation of successful adaptation actions. However, the success of these actions when we consider the interdependencies among sectors remains debatable. This paper aims to assess who benefits from implementing adaptation options in a multiuser river basin to both climate-induced and demographic stress on water use. Our analysis relies on a hydro-economic model that considers two sets of water users: agriculture and urban households. We innovate in our modelling approach by analyzing and explicitly integrating the household-level economic behavior through its water demand. We assess the cross-user consequences of autonomous and planned adaptation actions. We provide insights into the different trade-offs at the basin level, demonstrating the compatibilities and divergences between agriculture and household-level water demand. We found different consequences of implementing either autonomous or planned adaptation measures. For instance, a decentralized scheme would drive negative implications for the entire basin, although the less water-intensive sector will be better off. On the other hand, different policy interventions would drive positive consequences for the entire basin, with the most water-intensive sector benefiting the most. These results highlight the distributional consequences across users of different adaptation measures. | |
| Reconciling livestock production and wild herbivore conservation: challenges and opportunities | Trends in Ecology and Evolution | Pozo, R.; Cusack, J.; Acebes, P.; Malo, J.; Traba, J.; Iranzo, E.; Morris-Trainor, Z.; Minderman, J.; Bunnefeld, N.; Radic-Schilling, S.; Moraga, C.; Arriagada, R.; Corti, P. | 2021 | Cambio de Uso de Suelo | 10.1016/j.tree.2021.05.002 | https://doi.org/10.1016/j.tree.2021.05.002 | 750-761 | Vol: 36 Issue: 8 | 0169-5347 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Increasing food security and preventing further loss of biodiversity are two of humanity's most pressing challenges. Yet, efforts to address these challenges often lead to situations of conflict between the interests of agricultural production and those of biodiversity conservation. Here, we focus on conflicts between livestock production and the conservation of wild herbivores, which have received little attention in the scientific literature. We identify four key socio-ecological challenges underlying such conflicts, which we illustrate using a range of case studies. We argue that addressing these challenges will require the implementation of co-management approaches that promote the participation of relevant stakeholders in processes of ecological monitoring, impact assessment, decision-making, and active knowledge sharing. © 2021 The Authors |
| A multispecies assessment of wildlife impacts on local community livelihoods | Conservation Biology | Pozo, R.; LeFlore, E.; Duthie, A.; Bunnefeld, N.; Jones, I.; Minderman, J.; Rakotonarivo, O.; Cusack, J. | 2021 | Cambio de Uso de Suelo | 10.1111/cobi.13565 | https://onlinelibrary.wiley.com/doi/10.1111/cobi.13565 | 297-306 | Vol: 35 Issue: 1 | 0888-8892, 1523-1739 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access; Hybrid Gold Open Access | English | Conflicts between the interests of agriculture and wildlife conservation are a major threat to biodiversity and human well-being globally. Addressing such conflicts requires a thorough understanding of the impacts associated with living alongside protected wildlife. Despite this, most studies reporting on human–wildlife impacts and the strategies used to mitigate them focus on a single species, thus oversimplifying often complex systems of human–wildlife interactions. We sought to characterize the spatiotemporal patterns of impacts by multiple co-occurring species on agricultural livelihoods in the eastern Okavango Delta Panhandle in northern Botswana through the use of a database of 3264 wildlife-incident reports recorded from 2009 to 2015 by the Department of Wildlife and National Parks. Eight species (African elephants [Loxodonta africana], hippopotamuses [Hippopotamus amphibious], lions [Panthera leo], cheetah [Acinonyx jubatus], African wild dogs [Lycaon pictus], hyenas [Crocuta crocuta], leopards [Panthera pardus], and crocodiles [Crocodylus niloticus]) appeared on incident reports, of which 56.5% were attributed to elephants. Most species were associated with only 1 type of damage (i.e., either crop damage or livestock loss). Carnivores were primarily implicated in incident reports related to livestock loss, particularly toward the end of the dry season (May–October). In contrast, herbivores were associated with crop-loss incidents during the wet season (November–April). Our results illustrate how local communities can face distinct livelihood challenges from different species at different times of the year. Such a multispecies assessment has important implications for the design of conservation interventions aimed at addressing the costs of living with wildlife and thereby mitigation of the underlying conservation conflict. Our spatiotemporal, multispecies approach is widely applicable to other regions where sustainable and long-term solutions to conservation conflicts are needed for local communities and biodiversity. |
| Oceanography time series reveals annual asynchrony input between oceanic and estuarine waters in Patagonian fjords | Science of The Total Environment | Pérez-Santos, I.; Díaz, P.; Silva, N.; Garreaud, R.; Montero, P.; Henríquez-Castillo, C.; Barrera, F.; Linford, P.; Amaya, C.; Contreras, S.; Aracena, C.; Pinilla, E.; Altamirano, R.; Vallejos, L.; Pavez, J.; Maulen, J. | 2021 | Agua y Extremos | 10.1016/j.scitotenv.2021.149241 | https://linkinghub.elsevier.com/retrieve/pii/S004896972104314X | 149241 | Vol: 798 | 00489697 | Thomson Reuters ISI (SCIE) | English | The postglacial Patagonian fjord system along the west coast of southern South America is one of the largest stretches of the southern hemisphere (SH) fjord belt, influenced by the SH westerly wind belt and continental freshwater input. This study reports a 3-year monthly time series (2017–2020) of physical and biogeochemical parameters obtained from the Reloncaví Marine Observatory (OMARE, Spanish acronym) at the northernmost embayment and fjord system of Patagonia. The main objective of this work was to understand the land–atmosphere–ocean interactions and to identify the mechanisms that modulate the density of phytoplankton. A key finding of this study was the seasonally varying asynchronous input of oceanic and estuarine water. Surface lower salinity and warmer estuarine water arrived in late winter to summer, contributing to water column stability, followed by subsurface higher salinity and less warmer oceanic water during fall–winter. In late winter 2019, an interannual change above the picnocline due to the record-high polarity of the Indian Ocean Dipole inhibited water column stability. The biogeochemical parameters (NO3−, NO2−, PO43−, Si(OH)4, pH, and dissolved oxygen) responded to the surface annual salinity variations, and oceanic water mass contributed greatly to the subsurface inorganic nutrient input. The water column N/P ratio indicated that no eutrophication occurred, even under intense aquaculture activity, likely because of the high ventilation dynamics of the Reloncaví Sound. Finally, a shift in phytoplankton composition, characterized by surface chlorophyll-a maxima in late winter and deepening of spring–summer blooms related to the physicochemical conditions of the water column, was observed. Our results support the ecosystem services provided by local oceanography processes in the north Patagonian fjords. Here, the anthropogenic impact caused by economic activities could be, in part, chemically reduced by the annual ventilation cycle mediated by the exchange of oceanic water masses into Patagonian fjords. | |
| Urban Heat Islands and Vulnerable Populations in a Mid-Size Coastal City in an Arid Environment | Atmosphere | Quintana-Talvac, C.; Corvacho-Ganahin, O.; Smith, P.; Sarricolea, P.; Prieto, M.; Meseguer-Ruiz, O. | 2021 | Ciudades Resilientes | 10.3390/atmos12070917 | https://www.mdpi.com/2073-4433/12/7/917 | 917 | Vol: 12 Issue: 7 | 2073-4433 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Arica is a coastal city located in northern Chile, in the Atacama Desert. The behavior of surface temperatures in the city between 1985 and 2019 was studied using Landsat satellite images, leading to the identification of surface urban heat islands (SUHI), surface urban cold islands (SUCI), and average temperature zones. The higher intensities of the SUHI reach values of almost 45 °C and the SUCI lower values are below 13 °C. From the socioeconomic characterisation of the population based on indicators retrieved from the 2012 and 2017 population censuses, we identified that during the study period there was a lower presence of SUHI, but these were linked to spaces of lower socioeconomic level and, for the most part, would form new urban spaces within the city. On the other hand, SUCI had a greater spatial presence in the study area and in the urban morphology, being found mostly in areas of high socioeconomic level and in consolidated spaces with few possibilities of generating new constructions. |
| Tree-Holes as Alternative Reproductive Sites of Batrachyla antartandica Barrio, 1967 (Anura: Batrachylidae) | South American Journal of Herpetology | Rabanal, F.; Úbeda, C.; Tejo, C.; Lavilla, E. | 2021 | Cambio de Uso de Suelo | 10.2994/SAJH-D-18-00064.1 | https://bioone.org/journals/south-american-journal-of-herpetology/volume-20/issue-1/SAJH-D-18-00064.1/Tree-Holes-as-Alternative-Reproductive-Sites-of-Batrachyla-antartandica-Barrio/10.2994/SAJH-D-18-00064.1.full | 24-32 | Vol: 20 Issue: 1 | 1808-9798 | Thomson Reuters ISI (SCIE) | English | Although the original description of Batrachyla antartandica categorically states that the species should not be considered as arboreal, our field observations show that it has excellent climbing abilities. Associated with this fact, B. antartandica shows an alternative mode of reproduction that involves the use of tree-trunk cavities filled with water as a site for calling, reproduction, development, and metamorphosis. As far as we know, B. antartandica is the only anuran species in the Valdivian temperate rainforests of Chile and Argentina with a completely arboreal life cycle. | |
| Different climate sensitivity for radial growth, but uniform for tree-ring stable isotopes along an aridity gradient in Polylepis tarapacana , the world’s highest elevation tree species | Tree Physiology | Rodriguez-Caton, M.; Andreu-Hayles, L.; Morales, M.; Daux, V.; Christie, D.; Coopman, R.; Alvarez, C.; Rao, M.; Aliste, D.; Flores, F.; Villalba, R. | 2021 | Agua y Extremos | 10.1093/treephys/tpab021 | https://academic.oup.com/treephys/article/41/8/1353/6144557 | 1353-1371 | Vol: 41 Issue: 8 | 1758-4469 | Thomson Reuters ISI (SCIE) | English | Abstract Tree growth is generally considered to be temperature limited at upper elevation treelines, yet climate factors controlling tree growth at semiarid treelines are poorly understood. We explored the influence of climate on stem growth and stable isotopes for Polylepis tarapacana Philipi, the world’s highest elevation tree species, which is found only in the South American Altiplano. We developed tree-ring width index (RWI), oxygen (δ18O) and carbon (δ13C) chronologies for the last 60 years at four P. tarapacana stands located above 4400 m in elevation, along a 500 km latitude aridity gradient. Total annual precipitation decreased from 300 to 200 mm from the northern to the southern sites. We used RWI as a proxy of wood formation (carbon sink) and isotopic tree-ring signatures as proxies of leaf-level gas exchange processes (carbon source). We found distinct climatic conditions regulating carbon sink processes along the gradient. Current growing-season temperature regulated RWI at northern-wetter sites, while prior growing-season precipitation determined RWI at arid southern sites. This suggests that the relative importance of temperature to precipitation in regulating tree growth is driven by site water availability. By contrast, warm and dry growing seasons resulted in enriched tree-ring δ13C and δ18O at all study sites, suggesting that similar climate conditions control carbon-source processes along the gradient. Site-level δ13C and δ18O chronologies were significantly and positively related at all sites, with the strongest relationships among the southern drier stands. This indicates an overall regulation of intercellular carbon dioxide via stomatal conductance for the entire P. tarapacana network, with greater stomatal control when aridity increases. This manuscript also highlights a coupling (decoupling) between physiological processes at leaf level and wood formation as a function of similarities (differences) in their climatic sensitivity. This study contributes to a better understanding and prediction of the response of high-elevation Polylepis woodlands to rapid climate changes and projected drying in the Altiplano. |
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| Drivers of dinoflagellate benthic cyst assemblages in the NW Patagonian Fjords System and its adjacent oceanic shelf, with a focus on harmful species | Science of The Total Environment | Rodríguez-Villegas, C.; Lee, M.; Salgado, P.; Figueroa, R.; Baldrich, Á.; Pérez-Santos, I.; Tomasetti, S.; Niklitschek, E.; Díaz, M.; Álvarez, G.; Marín, S.; Seguel, M.; Farías, L.; Díaz, P. | 2021 | Zonas Costeras | 10.1016/j.scitotenv.2021.147378 | https://linkinghub.elsevier.com/retrieve/pii/S0048969721024499 | 147378 | Vol: 785 | 0048-9697 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | In recent decades, the alteration of coastal food webs (via aquaculture, fishing, and leisure activities), nutrient loading, and an expansion of monitoring programs have prompted an apparent worldwide rise in Harmful Algae Blooms (HABs). Over this time, a parallel increase in HABs has also been observed in the Chilean southern austral region (Patagonia fjords). HAB species like Alexandrium catenella—responsible for Paralytic Shellfish Poisoning (PSP)—are of great public concern due to their negative socioeconomic impacts and significant northward geographical range expansion. Many toxic dinoflagellate species (like A. catenella) produce benthic resting cysts, yet a holistic understanding of the physical-chemical and biological conditions influencing the distributions of cysts in this region is lacking. In this study, we measured a combination of hydrographic (temperature, salinity, and dissolved oxygen) and sediment physical-chemical properties (temperature, pH and redox potential), in addition to meiofaunal abundances –as sediment bioturbators and potential cyst predators– to determine the factors influencing dinoflagellate cyst distribution, with emphasis on A. catenella in and around a “hotspot” area of southern Chile. An analysis of similarities (ANOSIM) test revealed significant differences (p < 0.011) in cyst assemblages between the fjords and oceanic environments. Permutational Analysis of Variance (PERMANOVA) showed significant effects of sediment temperature and silt proportion in explaining differences in the cyst assemblages. A generalized linear model (GLM) indicated that sediment temperature, silt/sand, anoxic conditions, and low abundances of Harpacticoida —a meiofauna herbivore group and potential bioturbator— are associated with the higher resting cyst abundances of the harmful species A. catenella. The implications for A. catenella resting cysts dynamics are discussed, highlighting physical-chemical and biological interactions and their potential for PSP outbreak initiation. |
| Comité Científico de Cambio Climático: Informe previo de la Estrategia Climática de Largo Plazo | Rojas, M.; Farías, L.; González, H.; Marquet, P.; Muñoz, J.; Palma, R.; Stehr, A.; Vicuña, S. | 2021 | Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://comitecientifico.minciencia.gob.cl/wp-content/uploads/2021/11/Informe_Previo_ECLP_07.pdf | |||||||||
| Chile: elect a president to strengthen climate action, not weaken it | Nature | Rojas, M.; Muñoz, J.; Palma-Behnke, R.; Marquet, P.; Stehr, A.; González, H. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1038/d41586-021-03662-5 | https://www.nature.com/articles/d41586-021-03662-5 | 386-386 | Vol: 600 Issue: 7889 | 0028-0836 | Thomson Reuters ISI (SCIE) | English | ||
| Assessment of GPM IMERG satellite precipitation estimation and its dependence on microphysical rain regimes over the mountains of south-central Chile | Atmospheric Research | Rojas, Y.; Minder, J.; Campbell, L.; Massmann, A.; Garreaud, R. | 2021 | Agua y Extremos | 10.1016/j.atmosres.2021.105454 | https://linkinghub.elsevier.com/retrieve/pii/S0169809521000065 | 105454 | Vol: 253 | 0169-8095 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Satellite data provide crucial information for those places lacking precipitation observations from ground-based sensors, especially over oceans, mountain regions, or developing countries. This is the case over much of South America, including Chile, a country with complex topography that has limited long-term precipitation records and high-elevation data, and no operational weather radars. This study focuses on investigating the skill of the Global Precipitation Measurement (GPM) Integrated Multi-Satellite Retrieval for GPM (IMERG: version 6) quantitative precipitation estimation (QPE). IMERG is assessed against ground-based observations from two field campaigns that took place near 36°S: The Chilean Coastal Orographic Precipitation Experiment (CCOPE; winter 2015), which collected data over the coastal mountain range, and The Chilean Orographic and Mesoscale Precipitation Study (ChOMPS; winter 2016), which collected observations in a transect from the coast to the Andes. To characterize how IMERG performance depends on microphysical regime, we used data from profiling radars and rain gauge measurements to classify rainfall into regimes including “ice-initiated rain” and “warm rain”, characterized by the presence or absence of a well-defined melting layer respectively. Rain gauge data was used to evaluate performance of IMERG QPE overall and for these two regimes. IMERG depicts the general spatial pattern of observed orographic enhancement but highly underestimates the magnitude of this enhancement. At higher elevations during CCOPE, IMERG underestimated the total amount of rainfall by 50%, while during ChOMPS the underestimation was by 16%. For CCOPE, at higher elevation sites, IMERG underestimated ice-initiated rain by 30% and underestimated warm rain by 70%. For ChOMPS, the underestimation at the Andes site was 33% for ice-initiated rain and 50% for warm rain. IMERG QPE for both field campaigns showed larger underestimations for warm rain periods and at higher elevations than for ice-initiated rain periods. Documenting how IMERG performance varies with terrain and microphysical regime may help guide improvements to satellite-based QPE. |
| Centennial-scale eruptive diversity at Volcán Calbuco (41.3°S; Northwest Patagonia) deduced from historic tephra cover-bed and dendrochronologic archives | Journal of Volcanology and Geothermal Research | Romero, J.; Alloway, B.; Gutiérrez, R.; Bertín, D.; Castruccio, A.; Villarosa, G.; Schipper, C.; Guevara, A.; Bustillos, J.; Pisello, A.; Daga, R.; Montiel, M.; Gleeman, E.; González, M.; Morgavi, D.; Ribeiro Guevara, S.; Mella, M. | 2021 | Cambio de Uso de Suelo | 10.1016/j.jvolgeores.2021.107281 | https://linkinghub.elsevier.com/retrieve/pii/S0377027321001104 | 107281 | Vol: 417 | 0377-0273 | Thomson Reuters ISI (SCIE) | English | Since the late-18th Century, eye-witness accounts have documented a wide-spectrum of eruptive activity sourced from Volcán Calbuco located in northwest Patagonia. Despite these observations there is very little known about the eruptive products themselves that can account for this eruptive diversity. In this study, we examine the tephrostratigraphic record post-dating the interval 1578–1702 cal. yr BP, with emphasis on historical eruptions (i.e. <130 years, including the 2015 eruption) at proximal to medial distances (<16 km from source) to characterize the composition, distribution, volume and style of these units. At least 11 discrete tephra units are recognized which are in accord with documented eruptive activity between ~1760 CE and 2015. Juvenile pyroclasts from these units span a narrow compositional range from basaltic-andesite to andesite (55–60 wt% SiO2), and contain plagioclase (71–73%), pyroxene (~21%), cristobalite (3–5%) and scarce olivine and Ti-magnetite (1–2%). The largest documented historic eruption occurred in 1893–95, and produced a thick mantle of coarse-grained tephra fallout (0.32–0.50 km3 non-DRE) accompanied by intense ballistic bomb barrage closer to source. The 1893–95 eruption is comparable to the 1961 and 2015 eruptions both in terms of magnitude and explosivity, despite pyroclastic density currents (PDCs) not being documented in 1893–95. Both the 1929 and 1961 eruptions generated lava-flows, tephra fallout and PDCs, from which the 1961 volume totalled ~0.17 km3 non-DRE, affecting valleys northeast, up to a distance of 6 km from the crater. In contrast, the 2015 eruption only produced PDCs, tephra fallout and ballistics (0.26–0.36 km3 non-DRE). Results obtained from dendrochronological analysis of Nothofagus dombeyi trees within the study area reveals growth suppression indicated by structural damage during the 1893, 1929 and 1961 eruptions, probably related to thicker overall accumulations of tephra. Collectively, the componentry, architecture and volume of historic (AD 1893, 1961 and 2015) Calbuco tephra indicate sub-Plinian parental events derived from more mafic products with disequilibrium textures, than smaller eruptions characterized by c. 60% wt. SiO2 probably triggered by crystal fractionation, providing a centennial time scale eruptive heterogeneity. This data is meaningful in terms of better understanding eruptive diversity at basaltic-andesite centers elsewhere that have high eruption frequencies (e.g. centennial time-scales). © 2021 Elsevier B.V. | |
| Assessment of landscape transformation in protected areas | Environmental Impact Assessment Review | Ruiz Pereira, S.; Fernández, J.; Herrera, J.; Olea, J. | 2021 | Ciudades Resilientes | 10.1016/j.eiar.2020.106472 | https://linkinghub.elsevier.com/retrieve/pii/S0195925520301347 | 106472 | Vol: 86 | 01959255 | Thomson Reuters ISI (SSCI) | English | Mountain protected landscapes continuously endure conflicts of appropriation that bear inherent transformations. One type of direct intervention is by Commercial Concessions within these areas, affecting their landscape value. The aim is to determine conceptual gaps in Environmental Impact Studies regarding landscape assessment and propose a way to improve them in this sense. Shortcomings regarding landscape are checked in different normative frameworks and tensions are analyzed through the case of a Commercial Concession grant within a Mountain Protected area in the South-Central Andes of Chile (38°22′S;71°35′W). Weak or absent definitions of landscape are found in normative frames and Environmental Impact guidelines. A reductionism of landscape as mere viewshed units avoids a proper differentiation for several types of economic transformations and conservation management purposes therein. Hence, transformations affecting the inherent value of landscape are latent under monitoring and legislation abiding practices. Tensions between protected areas and commercial concessions depend on landscape management strategies which are associated to capital gain uncertainties by risking the nonuse-value of landscape. This uncertainty as a natural insurance value can be integrated to conceptual analyses assessing landscape transformations and report their depreciation. These transformations of landscape value are deemed necessary to be implemented in Environmental Impact Assessment without having to discretize bipartite purposes in protected areas by assessing landscape value through conceptual and economic analyses. |
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| Permafrost evolution in a mountain catchment near Santiago de Chile | Journal of South American Earth Sciences | Ruiz Pereira, S.; Marquardt, C.; Beriain, E.; Lambert, F. | 2021 | Ciudades Resilientes | 10.1016/j.jsames.2021.103293 | https://linkinghub.elsevier.com/retrieve/pii/S0895981121001401 | 103293 | Vol: 109 | 08959811 | Thomson Reuters ISI (SCIE) | English | The Chilean Central Andes near Santiago are a semi-arid region with substantial frozen water reserves in their high altitude cryosphere. Millions of people depend on the Andean cryosphere for freshwater supply. Over the last sixty years, global warming has altered the mountains’ water balance, as the temperature rose, precipitation decreased, and deglacierization exposed hundreds of square kilometers. The distribution of solid water stored in soil permafrost and the potential effects of climate change on it are unknown. Here, we map favorable spots for permafrost occurrence at the “Monos de Agua” catchment, Aconcagua basin at 33°S, between 3600 and 5100 m a.s.l.. We identify these “cold spots” based on ground surface temperature and incoming solar radiation between 2017 and 2019. We suggest that these locations currently present permafrost and frozen water might actually be there. We confirmed a body of frozen water at one of these cold spots using an electrical resistivity survey. Our mapping suggests that at least 15 ± 7% of the catchment's surface is underlain by permafrost. Permafrost occurrence begins around 3600 m a.s.l. with low probability and only at locations with favorable conditions of low exposure and isolation. Permafrost occurrence probability increases with altitude, with the largest fraction present above 4200 m a.s.l. Our results suggest that the permafrost area in this region will decrease between 13 and 87% by the end of the century under the future global warming RCP scenarios. This event represents new challenges for the hydrological memory and water security planning in the Chilean Central Andes. |
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| Marco teórico de Transformación: Cómo nos transformamos para responder a los crecientes impactos del cambio climático | Salgado, M.; Aldunce, P. | 2021 | Agua y Extremos | https://bit.ly/3ISdjNz | 23 | El cambio climático es uno de los mayores desafíos que la ha tenido que enfrentar, requiriendo que la sociedad deba responder de manera urgente y colaborativa, con el objetivo de disminuir los crecientes impactos que este fenómeno produce, los que han ido en aumentando tanto en severidad, como en magnitud (IPCC, 2018). | |||||||
| Chileans, climate change and the natural environment: An audience segmentation study | Convergencia | Sapiains, R.; Azócar, G.; Ugarte, A.; Romero, J. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.29101/crcs.v28i0.15794 | https://convergencia.uaemex.mx/article/view/15794 | 1 | Vol: 28 | 2448-5799 | Thomson Reuters ISI (SSCI) | All Open Access; Gold Open Access | English | Hasta la fecha, en América Latina, las investigaciones sobre las dimensiones humanas del cambio climático son aún escasas. Para aportar a este campo, se realizó un estudio de segmentación de audiencia en Chile, que buscó explorar distintas perspectivas sobre este tema, utilizando datos de una Encuesta Nacional (n = 2170). Los resultados mostraron que la mayoría de los chilenos expresan altos niveles de preocupación y están de acuerdo en que el cambio climático está sucediendo y es causado principalmente por acciones humanas. Por otro lado, se encontraron diferencias en cosmovisiones, comportamientos, y percepciones de control, entre otros factores, permitiendo la identificación de tres grupos: pragmáticos, neoliberales y ambientalistas. Estos resultados pueden contribuir a diseñar estrategias de comunicación más efectivas para aumentar la concienciación y la acción climática. |
| Exploring the contours of climate governance: An interdisciplinary systematic literature review from a southern perspective | Environmental Policy and Governance | Sapiains, R.; Ibarra, C.; Jiménez, G.; O'Ryan, R.; Blanco, G.; Moraga, P.; Rojas, M. | 2021 | Gobernanza e Interfaz Ciencia y Política | 10.1002/eet.1912 | https://onlinelibrary.wiley.com/doi/full/10.1002/eet.1912 | 46-59 | Vol: 31 Issue: 1 | 1756-932X | Thomson Reuters ISI (SSCI) | English | Dealing with climate change is one of this century's most difficult challenges demanding new strategies to steer societies towards common transformational goals. A growing literature involving “climate governance” is evolving and should advance the discussion on transformations and the involvement of different actors in climate action. However, it is unclear that the Global South's particularities are being integrated. This study has a three-fold goal: (a) identify the different approaches to climate governance found in the mainstream literature, (b) explore the degree of integration of the Global South in those approaches, and (c) contribute to the ongoing discussion on this issue from a southern perspective. A systematic literature review on “climate governance” was conducted, distinguishing different approaches and their significance for the Global South. Results clustered in six groups use the characterizations: multi-level, global, adaptive, transnational, polycentric, and experimental/transformative. These terms account for different levels of decision-making, emerging values, and the importance of non-State and sub-national actors. Approaches vary, in relation to change and participation, from an incremental improvement focus to a more transformative perspective and from the promotion of community influence to processes based on traditional institutions. In the Global South, multi-level, multi-actor climate governance occurs in a context of deep inequality and asymmetric power relations, rising environmental conflicts, and a lack of adequate mechanisms for community participation. Addressing climate change here will require, acknowledging the State alone cannot solve the issue, that different views must be considered and that contextualized perspectives from the Global South must be integrated. |
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| The 21st-century fate of the Mocho-Choshuenco ice cap in southern Chile | The Cryosphere | Scheiter, M.; Schaefer, M.; Flández, E.; Bozkurt, D.; Greve, R. | 2021 | Agua y Extremos; Zonas Costeras | 10.5194/tc-15-3637-2021 | https://tc.copernicus.org/articles/15/3637/2021/ | 3637-3654 | Vol: 15 Issue: 8 | 1994-0424 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Glaciers and ice caps are thinning and retreating along the entire Andes ridge, and drivers of this mass loss vary between the different climate zones. The southern part of the Andes (Wet Andes) has the highest abundance of glaciers in number and size, and a proper understanding of ice dynamics is important to assess their evolution. In this contribution, we apply the ice-sheet model SICOPOLIS (SImulation COde for POLythermal Ice Sheets) to the Mocho-Choshuenco ice cap in the Chilean Lake District (40∘ S, 72∘ W; Wet Andes) to reproduce its current state and to project its evolution until the end of the 21st century under different global warming scenarios. First, we create a model spin-up using observed surface mass balance data on the south-eastern catchment, extrapolating them to the whole ice cap using an aspect-dependent parameterization. This spin-up is able to reproduce the most important present-day glacier features. Based on the spin-up, we then run the model 80 years into the future, forced by projected surface temperature anomalies from different global climate models under different radiative pathway scenarios to obtain estimates of the ice cap's state by the end of the 21st century. The mean projected ice volume losses are 56±16 % (RCP2.6), 81±6 % (RCP4.5), and 97±2 % (RCP8.5) with respect to the ice volume estimated by radio-echo sounding data from 2013. We estimate the uncertainty of our projections based on the spread of the results when forcing with different global climate models and on the uncertainty associated with the variation of the equilibrium line altitude with temperature change. Considering our results, we project a considerable deglaciation of the Chilean Lake District by the end of the 21st century. |
| Study of the urban microclimate using thermal UAV. The case of the mid-sized cities of Arica (arid) and Curicó (Mediterranean), Chile | Building and Environment | Smith, P.; Sarricolea, P.; Peralta, O.; Aguila, J.; Thomas, F. | 2021 | Ciudades Resilientes | 10.1016/j.buildenv.2021.108372 | https://linkinghub.elsevier.com/retrieve/pii/S0360132321007691 | 108372 | Vol: 206 | 03601323 | Thomson Reuters ISI (SCIE) | English | The study of the urban microclimate requires detailed information that is not available in most cities. The monitoring of climate parameters is reduced to a limited number of stations that are useful for urban climate studies at local or zonal scales. Detailed information is generally obtained through field work and fixed sensors. There are some climate parameters that can be obtained from remote sensors, such as the surface emission temperature, however, this information is only available in medium or low-resolution images from satellite images. Currently, it is possible to generate detailed information with Unmanned Aerial Vehicles (UAV). There are not many UAVs that can capture information on the surface emission temperature and those that can are, in general, prohibitively expensive. Only a few years ago a low-cost drone became available, the Mavic 2 dual, equipped with a thermal sensor, which qualitatively captures information from the thermal field. This article proposes the study of the urban microclimate of two mid-size Chilean cities using thermal images captured with the Mavic 2 dual drone, for which it was first necessary to process the images and convert their values to degrees Celsius. The values obtained are compared with those derived from Modis and Landsat satellite images, evaluating the correlation of the information. | |
| A global observational analysis to understand changes in air quality during exceptionally low anthropogenic emission conditions | Environment International | Sokhi, R.; Singh, V.; Querol, X.; Finardi, S.; Targino, A.; Andrade, M.; Pavlovic, R.; Garland, R.; Massagué, J.; Kong, S.; Baklanov, A.; Ren, L.; Tarasova, O.; Carmichael, G.; Peuch, V.; Anand, V.; Arbilla, G.; Badali, K.; Beig, G.; Belalcazar, L.; Bolignano, A.; Brimblecombe, P.; Camacho, P.; Casa... | 2021 | Ciudades Resilientes | 10.1016/j.envint.2021.106818 | https://linkinghub.elsevier.com/retrieve/pii/S0160412021004438 | 106818 | Vol: 157 | 01604120 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | This global study, which has been coordinated by the World Meteorological Organization Global Atmospheric Watch (WMO/GAW) programme, aims to understand the behaviour of key air pollutant species during the COVID-19 pandemic period of exceptionally low emissions across the globe. We investigated the effects of the differences in both emissions and regional and local meteorology in 2020 compared with the period 2015–2019. By adopting a globally consistent approach, this comprehensive observational analysis focuses on changes in air quality in and around cities across the globe for the following air pollutants PM2.5, PM10, PMC (coarse fraction of PM), NO2, SO2, NOx, CO, O3 and the total gaseous oxidant (OX = NO2 + O3) during the pre-lockdown, partial lockdown, full lockdown and two relaxation periods spanning from January to September 2020. The analysis is based on in situ ground-based air quality observations at over 540 traffic, background and rural stations, from 63 cities and covering 25 countries over seven geographical regions of the world. Anomalies in the air pollutant concentrations (increases or decreases during 2020 periods compared to equivalent 2015–2019 periods) were calculated and the possible effects of meteorological conditions were analysed by computing anomalies from ERA5 reanalyses and local observations for these periods. We observed a positive correlation between the reductions in NO2 and NOx concentrations and peoples’ mobility for most cities. A correlation between PMC and mobility changes was also seen for some Asian and South American cities. A clear signal was not observed for other pollutants, suggesting that sources besides vehicular emissions also substantially contributed to the change in air quality. As a global and regional overview of the changes in ambient concentrations of key air quality species, we observed decreases of up to about 70% in mean NO2 and between 30% and 40% in mean PM2.5 concentrations over 2020 full lockdown compared to the same period in 2015–2019. However, PM2.5 exhibited complex signals, even within the same region, with increases in some Spanish cities, attributed mainly to the long-range transport of African dust and/or biomass burning (corroborated with the analysis of NO2/CO ratio). Some Chinese cities showed similar increases in PM2.5 during the lockdown periods, but in this case, it was likely due to secondary PM formation. Changes in O3 concentrations were highly heterogeneous, with no overall change or small increases (as in the case of Europe), and positive anomalies of 25% and 30% in East Asia and South America, respectively, with Colombia showing the largest positive anomaly of ~70%. The SO2 anomalies were negative for 2020 compared to 2015–2019 (between ~25 to 60%) for all regions. For CO, negative anomalies were observed for all regions with the largest decrease for South America of up to ~40%. The NO2/CO ratio indicated that specific sites (such as those in Spanish cities) were affected by biomass burning plumes, which outweighed the NO2 decrease due to the general reduction in mobility (ratio of ~60%). Analysis of the total oxidant (OX = NO2 + O3) showed that primary NO2 emissions at urban locations were greater than the O3 production, whereas at background sites, OX was mostly driven by the regional contributions rather than local NO2 and O3 concentrations. The present study clearly highlights the importance of meteorology and episodic contributions (e.g., from dust, domestic, agricultural biomass burning and crop fertilizing) when analysing air quality in and around cities even during large emissions reductions. There is still the need to better understand how the chemical responses of secondary pollutants to emission change under complex meteorological conditions, along with climate change and socio-economic drivers may affect future air quality. The implications for regional and global policies are also significant, as our study clearly indicates that PM2.5 concentrations would not likely meet the World Health Organization guidelines in many parts of the world, despite the drastic reductions in mobility. Consequently, revisions of air quality regulation (e.g., the Gothenburg Protocol) with more ambitious targets that are specific to the different regions of the world may well be required. |
| High competitive ability of Centaurea melitensis L. (Asteraceae) does not increase in the invaded range | Biological Invasions | Sotes, G.; Cavieres, L.; Gómez-González, S. | 2021 | Cambio de Uso de Suelo | 10.1007/s10530-020-02396-1 | http://link.springer.com/10.1007/s10530-020-02396-1 | 693–703 | Vol: 23 | 1387-3547, 1573-1464 | Thomson Reuters ISI (SCIE) | English | Understanding why alien species become dominant in recipient communities requires a biogeographical perspective comparing the ecology of native and introduced populations. The genus Centaurea (Asteraceae) is well-known in invasion ecology because several aggressive invaders, including Centaurea melitensis L., belong to this genus. We compared the competitive ability of C. melitensis individuals from Spain (native range) and Chile (invaded range) when competing against Helenium aromaticum (Hook.) L.H. Bailey, a native relative from Chile. We performed germination bioassays and common garden competition experiments to compare: (1) the germination capacities of C. melitensis (Spain and Chile) and H. aromaticum (2) the potential allelopathic effect of leaf lixiviates of C. melitensis (Spain and Chile) on the seed germination of H. aromaticum, (3) the ability of C. melitensis from both origins to reduce the growth of H. aromaticum. No significant differences in the capacity of seed germination were found among C. melitensis from Chile and Spain and the native H. aromaticum. However, the seed germination of H. aromaticum was inhibited by the presence of C. melitensis leaves from Chile and Spain. Also, the biomass of H. aromaticum was reduced in the presence of C. melitensis, regardless of their origin. Our results demonstrate the competitive superiority of the invasive C. melitensis over H. aromaticum, but we found no evidence of an evolutionary increase in the competitive ability of the invader populations. Therefore, at least part of the invasive potential of C. melitensis seems to be acquired by selective processes in their original range. | |
| Precipitation declines influence the understory patterns in Nothofagus pumilio old-growth forests in northwestern Patagonia | Forest Ecology and Management | Soto, D.; Donoso, P.; Zamorano-Elgueta, C.; Ríos, A.; Promis, Á. | 2021 | Cambio de Uso de Suelo | 10.1016/j.foreco.2021.119169 | https://linkinghub.elsevier.com/retrieve/pii/S0378112721002577 | 119169 | Vol: 491 | 03781127 | Thomson Reuters ISI (SCIE) | English | Forest understories are essential to plant diversity and ecosystem functioning. However, studies about changes in understory patterns as affected by varying precipitation are scarce. Pure Nothofagus pumilio (common name: lenga) forests dominate the eastern side of the Andes mountains in Patagonia across an ample range of precipitation (~1500–500 mm). By studying the same forest type, in the same developmental stage (old-growth), we aimed to isolate the effects of precipitation upon these N. pumilio ecosystems, particularly for the understory. Three sites were selected with annual average precipitations of ~1000 mm (humid), ~800 mm (mesic), and 600 mm (dry), with a distance of 30 km between the humid and the dry sites, and only 18 km between the mesic and the dry sites. In each site, we established three 40 × 40 m plots in 4 blocks, and 30 1 m2 regeneration subplots within each plot. In each subplot we measured vascular plant cover, richness and diversity (alpha and beta), litter cover and coarse woody debris, plus several abiotic variables. We analyzed the data with mixed analysis of variance, differences of understory plant communities through blocked distance-based multivariate analysis of variance, and visualized the groups (sites) with non-metric multidimensional scaling. Indicator species at each site were identified through blocked species indicator analysis. The dry site differed significantly compared to the humid and mesic sites, with the lowest understory cover (4 vs. 82–78%), plant richness (15 vs. 25–26 species), and Simpson diversity index (0.05 vs. 0.66–0.64). Beta turnover diversity was higher between the dry site with either the humid and the mesic sites (βt = 0.613 and 0.561, respectively), which in turn had more species in common (βt = 0.115). An increase in exposed mineral soil, soil water content, and leaf area index occurred from dry to humid sites, and vice versa for transmitted radiation and litter cover. All sites had different indicator species, but with indicator values increasing from dry to humid sites. The dramatic impoverishment of the plant community once precipitation drops within the range of 800 and 600 mm per year in Northern Patagonia sets a warning to the potential effects of climate change upon N. pumilio-dominated forest ecosystems and their plant diversity. Some forest management and potential adaptation strategies are proposed. | |
| Scientific warnings could help to reduce farmed salmon mortality due to harmful algal blooms | Marine Policy | Soto, D.; León-Muñoz, J.; Garreaud, R.; Quiñones, R.; Morey, F. | 2021 | Agua y Extremos | 10.1016/j.marpol.2021.104705 | https://linkinghub.elsevier.com/retrieve/pii/S0308597X2100316X | 104705 | Vol: 132 | 0308597X | Thomson Reuters ISI (SSCI) | English | The increasing occurrence of harmful algal blooms (HABs) affecting mariculture has been related to climatic factors but also to increasing eutrophication of coastal zones, to which aquaculture may also contribute. The role of climate change on HABs may be increasingly relevant but scientific efforts to separate this from other causal factors are to date inconclusive. HABs have been a permanent threat to the aquaculture industry in southern Chile, yet government and farmers may have not paid enough attention to scientific information and advice, even when risk-based predictions and warnings have been provided. Here we describe eutrophication risk assessments for water bodies hosting salmon farms and climate change risk maps for the salmon industry in Chilean Patagonia, including the increase of HABs as a main threat. Assessments and maps were delivered in 2020 both to producers and to government. We show that such risk information and mapping could have lessened recent salmon mortality due to HABs (March-April 2021) if government and farmers had followed explicit recommendations to reduce salmon farming production in water bodies with higher risk. This measure would reduce Exposure and Sensitivity under the climate change risk framework used. We provide policy recommendations, including reviewing maximum salmon production in relevant water bodies such as fjords according to eutrophication risks, while paying attention to additional stress from climate change variability and trends. | |
| Trace elements in Antarctic penguins and the potential role of guano as source of recycled metals in the Southern Ocean | Chemosphere | Sparaventi, E.; Rodríguez-Romero, A.; Barbosa, A.; Ramajo, L.; Tovar-Sánchez, A. | 2021 | Zonas Costeras | 10.1016/j.chemosphere.2021.131423 | https://linkinghub.elsevier.com/retrieve/pii/S0045653521018956 | 131423 | Vol: 285 | 00456535 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Penguins dominate the Antarctic avifauna. As key animals in the Antarctic ecosystem, they are monitored to evaluate the ecological status of this pristine and remote region and specifically, they have been used as effective bioindicators suitable for long-term monitoring of metals in the Antarctic environment. However, studies about the role of this emblematic organism could play in the recycling of trace metals (TMs) in the Antarctic ecosystem are very limited. In this study we evaluate, using the peer review research articles already published and our own findings, the distribution of metals (i.e., Ca, Fe, Al, Na, Zn, Mg, Cu, K, Cd, Mn, Sr, Cr, Ni, Pb, Hg, V, Ba, Co, La, Ag, Rb, Hf, Sc, Au and Cs) and metalloids (As and Sb), measured in different biotic matrices, with emphasis on guano, of the Chinstrap (Pygoscelis antarcticus), Adélie (Pygoscelis adeliae) and Gentoo (Pygoscelis papua) penguins. Regarding bioactive metals, the high concentrations (μg g−1 dry weight) of Cu (2.0 ± 1.4) x 102, Fe (4.1 ± 2.9) x 102, Mn (30 ± 34) and Zn (210 ± 90) reported in the guano from all the penguin species studied including our data, are of the same order of magnitude as those reported for whale feces (μg g−1 dry weight): Cu (2.9 ± 2.4) x 102, Fe (1.5 ± 1.4) x 102, Mn (28 ± 17) and Zn (6.2 ± 4.3) x 102, and one order of magnitude higher than the metal contents in krill (μg g−1 dry weight) of Cu (10.2 ± 5.5), Fe (24 ± 29) and Zn (13.5 ± 1.7). This suggest that penguin's excretion products could be an important source of these essential elements in the surface water, with an estimated annual release on a breeding season for Cu, Fe, Mn, Zn respectively of 28, 56, 4 and 29 tons, for the Chinstrap, Adélie and Gentoo penguins. The results provide evidence on the potential influence of penguins recycling TMs in the surface layer of the water column. © 2021 The Authors |
| Antarctica and the Southern Ocean (2021) | Bulletin of the American Meteorological Society | Stammerjohn, S.; Scambos, T.; Adusumilli, S.; Barreira, S.; Bernhard, G.; Bozkurt, D.; Bushinsky, S.; Clem, K.; Colwell, S.; Coy, L.; De Laat, J.; Du Plessis, M.; Fogt, R.; Foppert, A.; Fricker, H.; Gardner, A.; Gille, S.; Gorte, T.; Johnson, B.; Keenan, E.; Kennett, D.; Keller, L.; Kramarova, N.; L... | 2021 | Zonas Costeras | 10.1175/BAMS-D-21-0081.1 | https://journals.ametsoc.org/view/journals/bams/102/8/BAMS-D-21-0081.1.xml | S317-S356 | Vol: 102 Issue: 8 | 0003-0007, 1520-0477 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | |
| Influence of Estuarine Water on the Microbial Community Structure of Patagonian Fjords | Frontiers in Marine Science | Tamayo-Leiva, J.; Cifuentes-Anticevic, J.; Aparicio-Rizzo, P.; Arroyo, J.; Masotti, I.; Díez, B. | 2021 | Zonas Costeras | 10.3389/fmars.2021.611981 | https://www.frontiersin.org/articles/10.3389/fmars.2021.611981/full | 611981 | Vol: 8 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Fjords are sensitive areas affected by climate change and can act as a natural laboratory to study microbial ecological processes. The Chilean Patagonian fjords (41–56°S), belonging to the Subantarctic ecosystem (46–60°S), make up one of the world’s largest fjord systems. In this region, Estuarine Water (EW) strongly influences oceanographic conditions, generating sharp gradients of oxygen, salinity and nutrients, the effects of which on the microbial community structure are poorly understood. During the spring of 2017 we studied the ecological patterns (dispersal and oceanographic factors) underlying the microbial community distribution in a linear span of 450 km along the estuarine-influenced Chilean Patagonian fjords. Our results show that widespread microbial dispersion existed along the fjords where bacterioplankton exhibited dependence on the eukaryotic phytoplankton community composition. This dependence was particularly observed under the low chlorophyll- a conditions of the Baker Channel area, in which a significant relationship was revealed between SAR11 Clade III and the eukaryotic families Pyrenomonadaceae (Cryptophyte) and Coccomyxaceae (Chlorophyta). Furthermore, dissolved oxygen and salinity were revealed as the main drivers influencing the surface marine microbial communities in these fjords. A strong salinity gradient resulted in the segregation of the Baker Channel prokaryotic communities from the rest of the Patagonian fjords. Likewise, Microbacteriaceae, Burkholderiaceae and SAR11 Clade III, commonly found in freshwater, were strongly associated with EW conditions in these fjords. The direct effect of EW on the microbial community structure and diversity of the fjords exemplifies the significance that climate change and, in particular, deglaciation have on this marine region and its productivity. |
| Comité Científico de Cambio Climático: La importancia de la ventilación | Tolvett, S.; Rondanelli, R.; Brevis, W.; Valdes, M.; Rojas, M. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://comitecientifico.minciencia.gob.cl/wp-content/uploads/2021/06/Tolvett-ventilacion_11.pdf | |||||||||
| Air pollution and COVID-19 lockdown in a large South American city: Santiago Metropolitan Area, Chile | Urban Climate | Toro A., R.; Catalán, F.; Urdanivia, F.; Rojas, J.; Manzano, C.; Seguel, R.; Gallardo, L.; Osses, M.; Pantoja, N.; Leiva-Guzman, M. | 2021 | Ciudades Resilientes | 10.1016/j.uclim.2021.100803 | https://linkinghub.elsevier.com/retrieve/pii/S221209552100033X | 100803 | Vol: 36 | 22120955 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The implementation of confinement and physical distancing measures to restrict people's activities and transit in the midst of the COVID-19 pandemic allowed us to study how these measures affect the air quality in urban areas with high pollution rates, such as Santiago, Chile. A comparative study between the concentrations of PM10, PM2.5, NOx, CO, and O3 during the months of March to May 2020 and the corresponding concentrations during the same period in 2017–2019 is presented. A combination of surface measurements from the air quality monitoring network of the city, remote satellite measurements, and simulations of traffic activity and road transport emissions allowed us to quantify the change in the average concentrations of each pollutant. Average relative changes of traffic emissions (between 61% and 68%) implied statistically significant concentrations reductions of 54%, 13%, and 11% for NOx, CO, and PM2.5, respectively, during the pandemic period compared to historical period. In contrast, the average concentration of O3 increased by 63% during 2020 compared to 2017–2019. The nonlinear response observed in the pollution levels can be attributed to the changes in the vehicular emission patterns during the pandemic and to the role of other sources such as residential emissions or secondary PM. © 2021 Elsevier B.V. |
| 13,000 years of sociocultural plant use in the Atacama Desert of northern Chile | Vegetation History and Archaeobotany | Ugalde, P.; McRostie, V.; Gayo, E.; García, M.; Latorre, C.; Santoro, C. | 2021 | Ciudades Resilientes | 10.1007/s00334-020-00783-1 | http://link.springer.com/10.1007/s00334-020-00783-1 | 213-230 | Vol: 30 Issue: 2 | 0939-6314, 1617-6278 | Thomson Reuters ISI (SCIE) | English | Throughout Earth’s most extreme environments, such as the Kalahari Desert or the Arctic, hunter–gatherers found ingenious ways to obtain proteins and sugars provided by plants for dietary requirements. In the hyperarid Atacama Desert, wild plant resources are scarce and unevenly distributed due to limited water availability. This study brings together all available archaeobotanical evidence gathered in the Atacama Desert from the Late Pleistocene (ca. 13,000 cal bp) until the Inka epoch (ca. 450 cal bp) to help us comprehend when these populations acquired and managed useful plants from the coastal zone, Intermediate Depression, High Andes, as well as tropical and subtropical ecosystems. Widespread introduction of farming crops, water control techniques and cultivation of diverse plants by 3,000 cal bp ended not only a chronic food shortage, but also led to the establishment of a set of staple foods for the Atacama Desert dwellers, a legacy that remains visible today. By contrasting these trends with major sociocultural changes, together with palaeodemographic and climatic fuctuations, we note that humans adapted to, and transformed this hyperarid landscape and oscillating climate, with plants being a key factor in their success. This long-term process, which we term the “Green Revolution”, coincided with an exponential increase in the number of social groups inhabiting the Atacama Desert during the Late Holocene. |
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| An Integrated Framework to Streamline Resilience in the Context of Urban Climate Risk Assessment | Earth's Future | Urquiza, A.; Amigo, C.; Billi, M.; Calvo, R.; Gallardo, L.; Neira, C.; Rojas, M. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1029/2020EF001508 | https://onlinelibrary.wiley.com/doi/10.1029/2020EF001508 | art: e2020EF001508 | Vol: 9 Issue: 9 | 2328-4277, 2328-4277 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Cities are increasingly acknowledged as crucial when facing climate change—and the environmental crisis more in general—, offering challenges and opportunities in terms of both mitigation and adaptation. Climate change-sensitive urban governance requires proactive, integrated, and contextualized approaches, making room for the complex, multilayered, multiscalar, and dynamic processes constituting a city. The notion of “resilience” has been acquiring growing recognition as a flexible and powerful concept to respond to these challenges. Resilience itself, however, is also a polysemic notion, often treated as little more than a catchword or a wishful aim or superimposed with other climate-related terms, such as risk, vulnerability, or adaptation. To promote a stronger integration among different problem-settings and epistemic communities, this paper advances six analytical distinctions aiming to provide structure and articulation to existing definitions of the concept of “resilience.” Likewise, it offers an integrated analytical framework and methodological pipeline to streamline resilience analysis in the context of urban climate risk assessment. The framework is specially defined to link up with the definition of climate risk provided by the Intergovernmental Panel on Climate Change (IPCC) latest Assessment Reports and is illustrated through examples derived from the recent experience of the Chilean Climate Risk Atlas. |
| Climate response and drought resilience of Nothofagus obliqua secondary forests across a latitudinal gradient in south-central Chile | Forest Ecology and Management | Urrutia-Jalabert, R.; Barichivich, J.; Rozas, V.; Lara, A.; Rojas, Y.; Bahamondez, C.; Rojas-Badilla, M.; Gipoulou-Zuñiga, T.; Cuq, E. | 2021 | Cambio de Uso de Suelo | 10.1016/j.foreco.2021.118962 | https://linkinghub.elsevier.com/retrieve/pii/S0378112721000517 | 118962 | Vol: 485 | 0378-1127 | Thomson Reuters ISI (SCIE) | English | The climate response and resilience of tree growth to drought events have been widely reported for forests from the Northern Hemisphere. However, studies are much scarcer in the extra-tropical forests of southern South America. Mediterranean and Temperate forests of Chile are suffering from a moderate warming and a sustained precipitation decrease, occurring on top of an unprecedented megadrought since 2010. This study evaluated tree-growth patterns, the climate response and drought resilience of nine secondary Nothofagus obliqua forests across a latitudinal gradient from Mediterranean to Temperate climate in the Andes of Chile (35.7° to 40.3° S). Moreover, to improve the understanding of the spatial variation in productivity patterns, this research assessed trends in the maximum Normalized Difference Vegetation Index (peak in the NDVI) across the gradient for 2001–2018. Tree-growth patterns were highly influenced by stand dynamics, with steep decreasing trends in most of the stands related to a gradual canopy closure. Productivity trends had a flat pattern north of 38oS, but positive trends south of this latitude, which were mostly attributed to stand development. Tree growth was positively related to precipitation in all the sites, with annual and summer rainfall being more important in the north (Mediterranean climate) and south (Temperate climate), respectively. Conversely, maximum temperature had a negative effect on growth in most of the studied forests. This implies that projected warmer and drier conditions may have a detrimental effect on N. obliqua growth during coming decades. The two northern stands, located at the species dry range edge, were among the most resilient to drought and have not been strongly affected by the current megadrought in the area. Overall climate conditions, however, do not define the tolerance of stands to droughts, likely because local environmental and forests conditions play a key role. Although droughts have not strongly impacted the growth of N. obliqua across its distribution so far, future studies should assess the effects of the current long-term megadrought on growth resilience, and physiological studies should address the impacts of droughts and heat waves on forest function beyond what growth can unveil. © 2021 Elsevier B.V. | |
| Long-Term Exposure to Fine and Coarse Particulate Matter and COVID-19 Incidence and Mortality Rate in Chile during 2020 | International Journal of Environmental Research and Public Health | Valdés Salgado, M.; Smith, P.; Opazo, M.; Huneeus, N. | 2021 | Ciudades Resilientes | 10.3390/ijerph18147409 | https://www.mdpi.com/1660-4601/18/14/7409 | 7409 | Vol: 18 Issue: 14 | 1660-4601 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access; Green Open Access | English | Background: Several countries have documented the relationship between long-term exposure to air pollutants and epidemiological indicators of the COVID-19 pandemic, such as incidence and mortality. This study aims to explore the association between air pollutants, such as PM2.5 and PM10, and the incidence and mortality rates of COVID-19 during 2020. Methods: The incidence and mortality rates were estimated using the COVID-19 cases and deaths from the Chilean Ministry of Science, and the population size was obtained from the Chilean Institute of Statistics. A chemistry transport model was used to estimate the annual mean surface concentration of PM2.5 and PM10 in a period before the current pandemic. Negative binomial regressions were used to associate the epidemiological information with pollutant concentrations while considering demographic and social confounders. Results: For each microgram per cubic meter, the incidence rate increased by 1.3% regarding PM2.5 and 0.9% regarding PM10. There was no statistically significant relationship between the COVID-19 mortality rate and PM2.5 or PM10. Conclusions: The adjusted regression models showed that the COVID-19 incidence rate was significantly associated with chronic exposure to PM2.5 and PM10, even after adjusting for other variables. |
| Overcoming energy poverty through micro-grids: An integrated framework for resilient, participatory sociotechnical transitions | Energy Research & Social Science | Valencia, F.; Billi, M.; Urquiza, A. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1016/j.erss.2021.102030 | https://linkinghub.elsevier.com/retrieve/pii/S2214629621001237 | 102030 | Vol: 75 | 22146296 | Thomson Reuters ISI (SSCI) | English | Nowadays, the sustainability of micro-grids has received much attention in the research community since micro-grids are becoming an appealing alternative to provide clean energy access to rural communities, and by this token, contribute to overcome energy poverty. The aim of this paper was to investigate the sustainability of micro-grids through the analysis of their resilience. In this regard, an integrated framework was developed combining socio-technical transitions with socio-ecological resilience concepts. This allows to pay attention at once to two dimensions of micro-grid sustainability: (i) the ability of the micro-grid to effectively transform the relationship between community, energy, and territory to make it more sustainable in economic, social and environmental terms; (ii) the sustainability of the micro-grid itself, namely, its ability to endure, adapt to and recover from changes in contextual factors which may limit its operativity over time. Methodological guidelines are offered for the participatory co-construction and monitoring of the micro-grid and its monitoring, supporting both dimensions. To illustrate our proposal, the micro-grid installed in Huatacondo, north of Chile, was used as test-bed. | |
| A source of isotopically light organic carbon in a low-pH anoxic marine zone | Nature Communications | Vargas, C.; Cantarero, S.; Sepúlveda, J.; Galán, A.; De Pol-Holz, R.; Walker, B.; Schneider, W.; Farías, L.; D’Ottone, M.; Walker, J.; Xu, X.; Salisbury, J. | 2021 | Zonas Costeras | 10.1038/s41467-021-21871-4 | http://www.nature.com/articles/s41467-021-21871-4 | 1604 | Vol: 12 Issue: 1 | 2041-1723 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Geochemical and stable isotope measurements in the anoxic marine zone (AMZ) off northern Chile during periods of contrasting oceanographic conditions indicate that microbial processes mediating sulfur and nitrogen cycling exert a significant control on the carbonate chemistry (pH, A T , DIC and p CO 2 ) of this region. Here we show that in 2015, a large isotopic fractionation between DIC and POC, a DIC and N deficit in AMZ waters indicate the predominance of in situ dark carbon fixation by sulfur-driven autotrophic denitrification in addition to anammox. In 2018, however, the fractionation between DIC and POC was significantly lower, while the total alkalinity increased in the low-pH AMZ core, suggesting a predominance of heterotrophic processes. An isotope mass-balance model demonstrates that variations in the rates of sulfur- and nitrogen-mediated carbon fixation in AMZ waters contribute ~7–35% of the POC exported to deeper waters. Thus, dark carbon fixation should be included in assessments of future changes in carbon cycling and carbonate chemistry due to AMZ expansion. |
| Informe de resultados Workshop "Oportunidades de investigación interdisciplinaria en el bosque esclerófilo frente al Cambio Global" | Vargas, S.; Pohl, N.; Delpiano, C.; Miranda, A.; Ovalle, J. | 2021 | Cambio de Uso de Suelo | https://bit.ly/3pk7iBN | El 26 de mayo del 2021, se realizó el Workshop “Oportunidades de investigación transdisciplinaria en el bosque esclerófilo frente al cambio global”, organizado por la iniciativa intercentros Cambios socio-ecológicos en ecosistemas en transición por cambio global. Este workshop tuvo como objetivo “generar oportunidades de investigación para mejorar la comprensión de las forzantes, impactos y adaptación del bosque esclerófilo afectado por el cambio global desde una perspectiva socioecológica”. |
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| The Chilean Tornado Outbreak of May 2019: Synoptic, mesoscale, and historical contexts | Bulletin of the American Meteorological Society | Vicencio, J.; Rondanelli, R.; Campos, D.; Valenzuela, R.; Garreaud, R.; Reyes, A.; Padilla, R.; Abarca, R.; Barahona, C.; Delgado, R.; Nicora, G. | 2021 | Agua y Extremos; Zonas Costeras | 10.1175/BAMS-D-19-0218.1 | https://journals.ametsoc.org/view/journals/bams/aop/BAMS-D-19-0218.1/BAMS-D-19-0218.1.xml | E611-E634 | Vol: 102 Issue: 3 | 0003-0007, 1520-0477 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | In late May 2019, at least seven tornadoes were reported within a 24-h period in southern Chile (western South America, 36°–38°S), including EF1 and EF2 events causing substantial damage to infrastructure, dozens of injuries, and one fatality. Despite anecdotal evidence and chronicles of similar historical events, the threat from tornadoes in Chile was regarded with skepticism until the 2019 outbreak. Herein, we describe the synoptic-scale features instrumental in the development of these tornadic storms, including an extended southwest–northeast trough along the South Pacific, with a large postfrontal instability area. Tornadic storms appear to be embedded in a modestly unstable environment (positive convective available potential energy but less than 1,000 J kg−1) and strong low- and midlevel wind shear, with high near-surface storm-relative helicity values (close to −200 m2 s−2), clearly differing from the Great Plains tornadoes in North America (with highly unstable environments) but resembling cold-season tornadoes previously observed in the midlatitudes of North America, Australia, and Europe. Reanalyzing rainfall and lightning data from the last 10 years, we found that tornadic storms in our region occur associated with locally extreme values of both CAPE and low-level wind shear, where a combination of the two in a low-level vorticity generation parameter appears as a simple first-order discriminant between tornadic and nontornadic environments. Future research should thoroughly examine historical events worldwide to assemble a database of high-shear, low-CAPE midlatitude storms and help improve our understanding of these storms’ underlying physics. |
| Development and resilience of deciduous Nothofagus forests since the Last Glacial Termination and deglaciation of the central Patagonian Andes | Palaeogeography, Palaeoclimatology, Palaeoecology | Villa-Martínez, R.; Moreno, P. | 2021 | Agua y Extremos | 10.1016/j.palaeo.2021.110459 | https://linkinghub.elsevier.com/retrieve/pii/S0031018221002443 | 110459 | Vol: 574 | 00310182 | Thomson Reuters ISI (SCIE) | English | Resolving the history of vegetation, fire, and glaciation on the eastern slope of the central Patagonian Andes (44°-49°S) since the Last Glacial Termination (T1) has proved difficult. This is due to the steep environmental gradients, vegetation heterogeneity, and scarcity of dated glacial deposits and geomorphic features. Unsurprisingly, published records show important heterogeneities which limit our understanding of the timing and magnitude of climate and vegetation changes, and their driving mechanisms since T1. In this paper, we describe sediment cores from small closed-basin lakes located in the deciduous Nothofagus forest zone near Coyhaique, Chile. Our results indicate that the Coyhaique glacier lobe abandoned its final Last Glacial Maximum position just before ~17.9 cal kyr BP and underwent a step-wise recession that included a halt/readvance that culminated at ~16.8 cal kyr BP, contemporaneous with the formation of an ice-dammed proglacial lake in the Coyhaique/Balmaceda sector. This glacial lake stood at its highest level between ~17.9–17.2 cal kyr BP (<726 and > 650 m.a.s.l.), lowered between ~17.2–16.2 cal kyr BP (<650 and > 570 m.a.s.l.), and disappeared thereafter. Herbs and shrubs, currently dominant in high Andean and Patagonian steppe environments, colonized the ice-free terrains distal to the glacier margins and proglacial lakes under cold and dry conditions. This was followed by a steady increase in Nothofagus between ~16.6–14.8 cal kyr BP that led to the establishment of forests starting at ~14.8 cal kyr BP. The Holocene started with a sudden increase in Nothofagus and disappearance of conifers in the context of increase fire activity between ~11.7–9.4 cal kyr BP. Closed-canopy Nothofagus forests persisted virtually unaltered from ~9.4 cal kyr BP to the present day, despite frequent explosive volcanism and millennial-scale variations in fire regimes, attesting to their extraordinary postglacial resilience which contrasts with their behavior during T1. Recent large-scale deforestation by fire, livestock grazing, and the spread of non-native invasive plant species drove the fastest and largest-magnitude shifts seen during the last ~16,500 years. | |
| Informe ¿Sequía o Aridización? ¿Qué haremos para enfrentar esta nueva normalidad? | Villanueva, L.; Ormazábal, B.; Garreaud, R. | 2021 | Agua y Extremos | https://bit.ly/3Ewl2O3 | La Sección de Emergencias y Gestión de Riesgos Agrícolas, en su propósito de generar conciencia y buscar soluciones para abordar los riesgos que afectan recurrentemente a la agricultura y sus agricultores, busca desarrollar espacios de integración, conversación y colaboración. Una de estas instancias es el Outlook Estacional, El encuentro realizado el 12 de mayo, titulado “¿Sequía o aridización? Outlook Estacional otoño-invierno 2021, reunió a representantes de los distintos sectores del agro, de las instituciones que otorgan servicios en meteorológica e hidrología, expertos de la academia y público en general. Su objetivo fue conocer y analizar la situación climática con el fin de proponer/acordar medidas de adaptación. El presente documento ha sido elaborado con el fin de dejar un testimonio del desarrollo del encuentro en su contenido técnico, académico e institucional, incluyendo las opiniones y aportes de los participantes. Así también, busca relevar la importancia de este tipo de encuentros para el público de interés, quienes requieren más información, herramientas, nueva tecnología, integración de los organismos público-privado e instancias participativas para, en conjunto, buscar/implementar soluciones y así minimizar los impactos de la sequía que se vienen presentando ya hace una década. |
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| Estimating discount rates for environmental goods: Are People’s responses inadequate to frequency of payments? | Journal of Environmental Economics and Management | Vásquez-Lavín, F.; Carrasco, M.; Barrientos, M.; Gelcich, S.; Ponce Oliva, R. | 2021 | Cambio de Uso de Suelo | 10.1016/j.jeem.2021.102446 | https://linkinghub.elsevier.com/retrieve/pii/S0095069621000292 | 102446 | Vol: 107 | 00950696 | Thomson Reuters ISI (SSCI) | English | Most stated preference studies estimate discount rates using a split-sample approach. Each sample faces a different payment frequency (for instance, 1, 5, 10) together with a randomly assigned bid vector; both the frequency of payments and the bid are fixed for a specific individual. This paper evaluates whether allowing respondents to choose their preferred payment frequency affects the estimated discount rate. We use data from a contingent valuation survey of a network of marine reserves and estimate discount rates using both an exogenous and endogenous approach. The former calculates the mean of the willingness to pay (WTP) for each sample and then finds the discount rate that makes the present value of each payment frequency equivalent. The latter estimates the WTP and the discount rate jointly. Results show that allowing people to choose the payment schedule significantly reduces the implicit discount rate. We observed the highest reductions in discount rates when we used all the information available from the valuation questions to bound the WTP distribution. Our analysis suggests that the exogenous approach would not be recommended for testing the adequacy of people's responses to the frequency of payments. | |
| Anthropogenic Perturbations to the Atmospheric Molybdenum Cycle | Global Biogeochemical Cycles | Wong, M.; Rathod, S.; Marino, R.; Li, L.; Howarth, R.; Alastuey, A.; Alaimo, M.; Barraza, F.; Carneiro, M.; Chellam, S.; Chen, Y.; Cohen, D.; Connelly, D.; Dongarra, G.; Gómez, D.; Hand, J.; Harrison, R.; Hopke, P.; Hueglin, C.; Kuang, Y.; Lambert, F.; Liang, J.; Losno, R.; Maenhaut, W.; Milando, C.... | 2021 | Ciudades Resilientes | 10.1029/2020GB006787 | https://onlinelibrary.wiley.com/doi/10.1029/2020GB006787 | art: e2020GB006787 | Vol: 35 Issue: 2 | 0886-6236, 1944-9224 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Molybdenum (Mo) is a key cofactor in enzymes used for nitrogen (N) fixation and nitrate reduction, and the low availability of Mo can constrain N inputs, affecting ecosystem productivity. Natural atmospheric Mo aerosolization and deposition from sources such as desert dust, sea-salt spray, and volcanoes can affect ecosystem function across long timescales, but anthropogenic activities such as combustion, motor vehicles, and agricultural dust have accelerated the natural Mo cycle. Here we combined a synthesis of global atmospheric concentration observations and modeling to identify and estimate anthropogenic sources of atmospheric Mo. To project the impact of atmospheric Mo on terrestrial ecosystems, we synthesized soil Mo data and estimated the global distribution of soil Mo using two approaches to calculate turnover times. We estimated global emissions of atmospheric Mo in aerosols (<10 μm in diameter) to be 23 Gg Mo yr−1, with 40%–75% from anthropogenic sources. We approximated that for the top meter of soil, Mo turnover times range between 1,000 and 1,000,000 years. In some industrialized regions, anthropogenic inputs have enhanced Mo deposition 100-fold, lowering the soil Mo turnover time considerably. Our synthesis of global observational data, modeling, and a mass balance comparison with riverine Mo exports suggest that anthropogenic activity has greatly accelerated the Mo cycle, with potential to influence N-limited ecosystems. |
| Dominant role of vertical air flows in the unprecedented warming on the Antarctic Peninsula in February 2020 | Communications Earth & Environment | Xu, M.; Yu, L.; Liang, K.; Vihma, T.; Bozkurt, D.; Hu, X.; Yang, Q. | 2021 | Zonas Costeras | 10.1038/s43247-021-00203-w | https://www.nature.com/articles/s43247-021-00203-w | 133 | Vol: 2 Issue: 1 | 2662-4435 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract Near-surface air temperature at the Argentinian research base Esperanza on the northern tip of the Antarctic Peninsula reached 18.3 °C on 6 February 2020, which is the highest temperature ever recorded on the entire Antarctic continent. Here we use weather observations since 1973 together with the ERA5 reanalysis to investigate the circulation that shaped the 2020 event, and its context over the past decades. We find that, during the 2020 event, a high-pressure ridge over the 40°-100°W sector and a blocking high on the Drake Passage led to an anticyclonic circulation that brought warm and moist air from the Pacific Ocean to the Antarctic Peninsula. Vertical air flows in a foehn warming event dominated by sensible heat and radiation made the largest contribution to the abrupt warming. A further analysis with 196 extreme warm events in austral summer between 1973 and 2020 suggests that the mechanisms behind the 2020 event form one of the two most common clusters of the events, exhibiting that most of the extreme warm events at Esperanza station are linked to air masses originating over the Pacific Ocean. |
| Spatial distribution and interannual variability of coastal fog and low clouds cover in the hyperarid Atacama Desert and implications for past and present Tillandsia landbeckii ecosystems | Plant Systematics and Evolution | del Río, C.; Lobos-Roco, F.; Latorre, C.; Koch, M.; García, J.; Osses, P.; Lambert, F.; Alfaro, F.; Siegmund, A. | 2021 | Ciudades Resilientes | 10.1007/s00606-021-01782-z | https://link.springer.com/10.1007/s00606-021-01782-z | 58 | Vol: 307 Issue: 5 | 0378-2697, 1615-6110 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The hyperarid Atacama Desert coast receives scarce moisture inputs mainly from the Pacific Ocean in the form of marine advective fog. The collected moisture supports highly specialized ecosystems, where the bromeliad Tillandsia landbeckii is the dominant species. The fog and low clouds (FLCs) on which these ecosystems depend are affected in their interannual variability and spatial distribution by global phenomena, such as ENSO. Yet, there is a lack of understanding of how ENSO influences recent FLCs spatial changes and their interconnections and how these variations can affect existing Tillandsia stands. In this study, we analyze FLCs occurrence, its trends and the influence of ENSO on the interannual variations of FLCs presence by processing GOES satellite images (1995–2017). Our results show that ENSO exerts a significant influence over FLCs interannual variability in the Atacama at ~ 20°S. Linear regression analyses reveal a relation between ENSO3.4 anomalies and FLCs with opposite seasonal effects depending on the ENSO phase. During summer (winter), the ENSO warm phase is associated with an increase (decrease) of the FLCs occurrence, whereas the opposite occurs during ENSO cool phases. In addition, the ONI Index explains up to ~ 50 and ~ 60% variance of the interannual FLCs presence in the T. landbeckii site during summer and winter, respectively. Finally, weak negative (positive) trends of FLCs presence are observed above (below) 1000 m a. s. l. These results have direct implications for understanding the present and past distribution of Tillandsia ecosystems under the extreme conditions characterizing our study area. |
| INEMA: High resolution inventory of atmospheric emissions from transport, industrial, energy, mining and residential sectors of Chile | Álamos, N.; Hunneus, N.; Osses, M.; Opazo, M.; Puja, S.; Pantoja, N. | 2021 | Ciudades Resilientes | 10.5281/zenodo.4784286 | https://zenodo.org/record/4784286 | Zenodo | English | Brief description This study presents the first high-resolution national inventory of anthropogenic emission for Chile (INEMA from spanish Inventario Nacional de EMisiones Antropogénicas). Emissions for vehicular, industrial, energy, mining and residential sectors are estimated for the period 2015-2017 and spatially distributed onto a high resolution grid (1 x 1 km approximately). The pollutants included are CO2, NOx, SO2, CO, VOCs, NH3, and particulate matter (PM10 and PM2.5) for all sectors. CH4 and Black Carbon are included for transport and residential sources, while Arsenic, Benzene, Mercury, Lead, Toluene, and Polychlorinated dibenzo-p-dioxins and Furan (PCDD / F) are estimated for energy, mining and industrial sources. This work compiles new activity data and emissions factors and distributes them geographically based on census and Chile´s road network information. This inventory should contribute to the design of policies that seek to mitigate climate change and improve air quality by providing policy makers, stakeholders and scientists with qualified scientific spatial explicit emission information. Metadata Each .tar file contain netcdf (.nc) files for each pollutant of the sector and year of the .tar file. Netcdf contains annual total emissions for the pollutant and year indicated per grid cell The emission grid consists of Chilean territory in WGS84 projection (lon-lat) with a spatial resolution of 0.01 * 0.01 degrees (lon x lat). The extension boundaries of the grid are: [(-76-56.3), (-66,-17)] The unit in the .nc files is Kilotonne/Km2/Year The dataset is described in Álamos, N., Hunneus, N., Opazo, M., Osses, M., Puja, S., Pantoja, N., Calvo, R., Denier Van Der Gon, H.A.C., Schueftan, A., Reyes, R., High resolution inventory of atmospheric emissions from transport, industrial, energy, mining and residential sectors of Chile, ESSD, in preparation, 2021 | |||||
| Vulnerabilidad hídrica territorial: Marco analítico y aplicaciones | Documento de trabajo NEST`-r3 N°3 | Álamos, N.; Monsalve, T.; Billi, M.; Lefort, I.; Allendes, A.; Navea, J.; Calvo, R.; Urquiza, A. | 2021 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.17605/OSF.IO/AGJ6P | https://bit.ly/3qhuD6n | La crisis hídrica evidenciada en los últimos años a nivel global ha puesto de relieve la necesidad de establecer metas unificadas para el logro del acceso universal al agua potable y saneamiento (Objetivo de Desarrollo Sostenible ODS 6), en el contexto de cambio climático que posiciona a la sequía como una de las amenazas más graves, presente en distintas regiones del mundo. Según las proyecciones del Grupo Intergubernamental de Expertos sobre el Cambio Climático (IPCC, 2014b), se espera una reducción de recursos renovables de aguas superficiales y subterráneas, un aumento de la frecuencia e intensidad de sequías a finales del siglo XXI (con arreglo al escenario RCP8,5), e incluso, disminuciones en la calidad del agua potable, debido a una mayor concentración de contaminantes durante la sequía (IPCC, 2014b). Además, la importancia de la seguridad hídrica se ve incrementada en la crisis sanitaria provocada por la propagación del COVID-19 (Staddon et al., 2020), ya que no sólo tensiona el funcionamiento de los servicios fundamentales para la salud y el desarrollo humano, sino que también tensiona los servicios hídricos donde el acceso ya está limitado para muchas personas en el mundo, restringiendo la posibilidad de un correcto lavado de manos (medida de higiene básica para combatir la propagación del virus) según la Organización Mundial de la Salud (WHO, 2020a). |
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| The role of climate variability in convergence of residential water consumption across Chilean localities | Environmental Economics and Policy Studies | Acuña, G.; Echeverría, C.; Godoy, A.; Vásquez, F. | 2020 | Cambio de Uso de Suelo | 10.1007/s10018-019-00249-3 | http://link.springer.com/10.1007/s10018-019-00249-3 | 89-108 | Vol: 22 Issue: 1 | 1432-847X, 1867-383X | Thomson Reuters ISI (ESCI) | English | This paper analyses the existence of convergence in residential water consumption across geographical regions using econometric methods taken from the economic growth literature and a panel of water consumption of 348 Chilean localities from 2010 to 2015. Convergence was found, and the main causes were factors related to economic and climate variables. | |
| Large-sample hydrology: recent progress, guidelines for new datasets and grand challenges | Hydrological Sciences Journal | Addor, N.; Do, H.; Alvarez-Garreton, C.; Coxon, G.; Fowler, K.; Mendoza, P. | 2020 | Agua y Extremos | 10.1080/02626667.2019.1683182 | https://www.tandfonline.com/doi/full/10.1080/02626667.2019.1683182 | 712-725 | Vol: 65 Issue: 5 | 0262-6667, 2150-3435 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Large-sample hydrology (LSH) relies on data from large sets (tens to thousands) of catchments to go beyond individual case studies and derive robust conclusions on hydrological processes and models. Numerous LSH datasets have recently been released, covering a wide range of regions and relying on increasingly diverse data sources to characterize catchment behaviour. These datasets offer novel opportunities, yet they are also limited by their lack of comparability, uncertainty estimates and characterization of human impacts. This article (i) underscores the key role of LSH datasets in hydrological studies, (ii) provides a review of currently available LSH datasets, (iii) highlights current limitations of LSH datasets and (iv) proposes guidelines and coordinated actions to overcome these limitations. These guidelines and actions aim to standardize and automatize the creation of LSH datasets worldwide, and to enhance the reproducibility and comparability of hydrological studies. |
| A Network for Advancing Dendrochronology, Dendrochemistry and Dendrohydrology in South America | Tree-Ring Research | Aguilera-Betti, I.; Lucas, C.; Ferrero, M.; Muñoz, A. | 2020 | Agua y Extremos | 10.3959/TRR2019-12 | https://bioone.org/journals/tree-ring-research/volume-76/issue-2/TRR2019-12/A-Network-for-Advancing-Dendrochronology-Dendrochemistry-and-Dendrohydrology-in-South/10.3959/TRR2019-12.full | 94 | Vol: 76 Issue: 2 | 1536-1098 | Thomson Reuters ISI (SCIE) | English | Tree-ring research (TRR) in South America (SA) continues to make important contributions in multiple sub-disciplines, including dendrochemistry and dendrohydrology. 1 2 communicate recent advances in TRR within a network of laboratories in Argentina, Brazil, Chile, Peru, and Uruguay. Novel methodologies and results in dendrochemistry and wood anatomy were also presented by collaborating researchers from German institutions. The report describes some of the research within the subdisciplines of tree-ring science, including dendrochemistry, anatomy and dendrohydrology, and their application to understanding spatio-temporal variability in heavy metal contamination, climate, hydrology, fire regimes and other critical components of South American forest and woodland ecosystems. The meeting demonstrated a broadening and diversification in the research and applications of TRR in SA, whereby collaboration across research centers has been critical for the advances made in broad-scale comparative studies as well as multi-proxy approaches and the study of global and hemisphere-scale climate phenomena. | |
| Low-Cost Ka-Band Cloud Radar System for Distributed Measurements within the Atmospheric Boundary Layer | Remote Sensing | Aguirre, R.; Toledo, F.; Rodríguez, R.; Rondanelli, R.; Reyes, N.; Díaz, M. | 2020 | Zonas Costeras | 10.3390/rs12233965 | https://www.mdpi.com/2072-4292/12/23/3965 | 3965 | Vol: 12 Issue: 23 | 2072-4292 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Radars are used to retrieve physical parameters related to clouds and fog. With these measurements, models can be developed for several application fields such as climate, agriculture, aviation, energy, and astronomy. In Chile, coastal fog and low marine stratus intersect the coastal topography, forming a thick fog essential to sustain coastal ecosystems. This phenomenon motivates the development of cloud radars to boost scientific research. In this article, we present the design of a Ka-band cloud radar and the experiments that prove its operation. The radar uses a frequency-modulated continuous-wave with a carrier frequency of 38 GHz. By using a drone and a commercial Lidar, we were able to verify that the radar can measure reflectivities in the order of −60 dBZ at 500 m of distance, with a range resolution of 20 m. The lower needed range coverage imposed by our case of study enabled a significant reduction of the instrument cost compared to existent alternatives. The portability and low-cost of the designed instrument enable its implementation in a distributed manner along the coastal mountain range, as well as its use in medium-size aerial vehicles or balloons to study higher layers. The main features, limitations, and possible improvements to the current instrument are discussed. |
| Taxonomic Novelty and Distinctive Genomic Features of Hot Spring Cyanobacteria | Frontiers in Genetics | Alcorta, J.; Alarcón-Schumacher, T.; Salgado, O.; Díez, B. | 2020 | Zonas Costeras | 10.3389/fgene.2020.568223 | https://www.frontiersin.org/articles/10.3389/fgene.2020.568223/full | 568223 | Vol: 11 | 1664-8021 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Several cyanobacterial species are dominant primary producers in hot spring microbial mats. To date, hot spring cyanobacterial taxonomy, as well as the evolution of their genomic adaptations to high temperatures, are poorly understood, with genomic information currently available for only a few dominant genera, including Fischerella and Synechococcus. To address this knowledge gap, the present study expands the genomic landscape of hot spring cyanobacteria and traces the phylum-wide genomic consequences of evolution in high temperature environments. From 21 globally distributed hot spring metagenomes, with temperatures between 32 and 75°C, 57 medium- and high-quality cyanobacterial metagenome-assembled genomes were recovered, representing taxonomic novelty for 1 order, 3 families, 15 genera and 36 species. Comparative genomics of 93 hot spring genomes (including the 57 metagenome-assembled genomes) and 66 non-thermal genomes, showed that the former have smaller genomes and a higher GC content, as well as shorter proteins that are more hydrophilic and basic, when compared to the non-thermal genomes. Additionally, the core accessory orthogroups from the hot spring genomes of some genera had a greater abundance of functional categories, such as inorganic ion metabolism, translation and post-translational modifications. Moreover, hot spring genomes showed increased abundances of inorganic ion transport and amino acid metabolism, as well as less replication and transcription functions in the protein coding sequences. Furthermore, they showed a higher dependence on the CRISPR-Cas defense system against exogenous nucleic acids, and a reduction in secondary metabolism biosynthetic gene clusters. This suggests differences in the cyanobacterial response to environment-specific microbial communities. This phylum-wide study provides new insights into cyanobacterial genomic adaptations to a specific niche where they are dominant, which could be essential to trace bacterial evolution pathways in a warmer world, such as the current global warming scenario. |
| Informe de devolución Valle del Aconcagua: Percepción y prácticas de adaptación. Segunda Parte: cambio climático, lluvias extremas y aumento de la temperatura (segunda edición) | Aldunce, P.; Sapiains, R.; Fuentes, C.; Marchant, G.; Moreau, A.; Velden, F.; Ugarte, A. | 2020 | Agua y Extremos | https://www.cr2.cl/wp-content/uploads/2020/10/Aconcagua_2020.pdf | 1-16 | El cambio climático es uno de los mayores desafíos que enfrenta la sociedad actual. El Valle de Aconcagua, ubicado en la Región de Valparaíso, no es ajeno a esta situación y donde se presentan desafíos que necesitan de un trabajo permanente, comprometido e informado por parte de todos los actores del territorio, para asegurar el bienestar presente y futuro. El presente documento resume los resultados del trabajo realizado con distintos actores sociales del Valle de Aconcagua, entre los años 2015 a 2018, respecto de lo que significa el cambio climático para ellos, los impactos que han experimentado, y las estrategias y prácticas que han desarrollado para enfrentarlo. Lo aquí presentado contribuye a la reflexión sobre qué podemos hacer para fortalecer las prácticas de adaptación y aumentar las capacidades para anticiparse, resistir y recuperarse de los efectos del cambio climático de manera oportuna y eficaz. |
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| Landscape Disturbance Gradients: The Importance of the Type of Scene When Evaluating Landscape Preferences and Perceptions | Land | Altamirano, A.; Gonzalez-Suhr, C.; Marien, C.; Catalán, G.; Miranda, A.; Prado, M.; Tits, L.; Vieli, L.; Meli, P. | 2020 | Cambio de Uso de Suelo | 10.3390/land9090306 | https://www.mdpi.com/2073-445X/9/9/306 | 306 | Vol: 9 Issue: 9 | 2073-445X | Thomson Reuters ISI (SSCI) | All Open Access; Gold Open Access | English | Understanding of people’s landscape preferences is important for decision-making about land planning, particularly in the disturbance patterns that usually occur in rural-urban gradients. However, the use of different types of images concerning the same landscape may influence social preferences and thus perceptions of landscape management and planning decisions. We evaluated landscape preferences and perceptions in four landscapes of southern Chile. We specifically: (1) compared people’s perceptions related to living in, visiting, the scenic beauty, well-being, risks, and level of landscape disturbance; and (2) evaluated the influence of the type of scene (i.e., eye-level or aerial images) in these preferences and perceptions. Preferences and perceptions resulted to be better when using eye-level (4.0 ± 1.1) than aerial (3.7 ± 0.6) images. In general, we observed a negative association between preferences and perceptions and the landscape disturbance; however, it was consistent when using aerial images but was masked when valuing landscape through eye-level images. Implications of these results are relevant because by far, most landscape preference studies use traditional eye-level images. Different types of scenes should be considered in order to embrace the landscape preferences and perceptions of all those involved and help decision-making in landscape planning. |
| Natural forests loss and tree plantations: large-scale tree cover loss differentiation in a threatened biodiversity hotspot | Environmental Research Letters | Altamirano, A.; Miranda, A.; Aplin, P.; Carrasco, J.; Catalán, G.; Cayuela, L.; Fuentes-Castillo, T.; Hernández, A.; Martínez-Harms, M.; Peluso, F.; Prado, M.; Reyes-Riveros, R.; Van Holt, T.; Vergara, C.; Zamorano-Elgueta, C.; Di Bella, C. | 2020 | Cambio de Uso de Suelo | 10.1088/1748-9326/abca64 | https://iopscience.iop.org/article/10.1088/1748-9326/abca64 | 124055 | Vol: 15 Issue: 12 | 1748-9326 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Distinguishing between natural forests from exotic tree plantations is essential to get an accurate picture of the world’s state of forests. Most exotic tree plantations support lower levels of biodiversity and have less potential for ecosystem services supply than natural forests, and differencing them is still a challenge using standard tools. We use a novel approach in south-central of Chile to differentiate tree cover dynamics among natural forests and exotic tree plantations. Chile has one of the world’s most competitive forestry industry and the region is a global biodiversity hotspot. Our collaborative visual interpretation method combined a global database of tree cover change, remote sensing from high-resolution satellite images and expert knowledge. By distinguishing exotic tree plantation and natural forest loss, we fit spatially explicit models to estimate tree-cover loss across 40 millions of ha between 2000 and 2016. We were able to distinguish natural forests from exotic tree plantations with an overall accuracy of 99% and predicted forest loss. Total tree cover loss was continuous over time, and the disaggregation revealed that 1 549 909 ha of tree plantations were lost (mean = 96 869 ha year−1 ), while 206 142 ha corresponded to natural forest loss (mean = 12 884 ha year−1 ). Mostly of tree plantations lost returned to be plantation (51%). Natural forests were converted mainly (75%) to transitional land covers (e.g. shrubland, bare land, grassland), and an important proportion of these may finish as tree plantation. This replacement may undermine objectives of increased carbon storage and biodiversity. Tree planting as a solution has gained increased attention in recen years with ambitious commitments to mitigate the effects of climate change. However, negative outcomes for the environment could result if strategies incentivize the replacement of natural forests into other land covers. Initiatives to reduce carbon emissions should encourage differentiating natural forests from exotic tree plantations and pay more attention on protecting and managing sustainably the former. |
| Policy Note: Policy Responses to Ensure Access to Water and Sanitation Services during COVID-19: Snapshots from the Environment for Development (EfD) Network | Water Economics and Policy | Amaechina, E.; Amoah, A.; Amuakwa-Mensah, F.; Amuakwa-Mensah, S.; Bbaale, E.; Bonilla, J.; Brühl, J.; Cook, J.; Chukwuone, N.; Fuente, D.; Madrigal-Ballestero, R.; Marín, R.; Nam, P.; Otieno, J.; Ponce, R.; Saldarriaga, C.; Lavin, F.; Viguera, B.; Visser, M. | 2020 | Cambio de Uso de Suelo | 10.1142/S2382624X20710022 | https://doi.org/10.1142/S2382624X20710022 | art: 2071002 | Vol: 6 Issue: 4 | 2382-624X | Thomson Reuters ISI (SCIE; SSCI) | English | This policy note provides a snapshot of water and sanitation measures implemented by governments in response to the COVID-19 pandemic in 14 countries in the Global South: Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Chile, Colombia, Ghana, Kenya, Nigeria, Panama, South Africa, Uganda and Vietnam. We find that many countries have taken action to stop utility disconnections due to non-payment. With the exception of Ghana and Vietnam, few countries are instituting new water subsidy programs, and are instead choosing to defer customers' bills for future payment, presumably when the pandemic recedes and households will be able to pay their bills. It is easier for the utilities' COVID-relief policies to target customers with piped connections who regularly receive bills. However, the situation for unconnected households appears more dire. Some countries (e.g., Ghana, Kenya, South Africa and Uganda) are attempting to provide unconnected households temporary access to water, but these households remain the most vulnerable. This health crisis has accentuated the importance of strong governance structures and resilient water service providers for dealing with external health, environmental and economic shocks. © 2020 World Scientific Publishing Company. | |
| ARCLIM Anexo: Piloto Riesgo integrado de Asentamientos Huanos. Conurbación Valparaíso - Viña del Mar | Amigo, C.; Alamos, N.; Arrieta, D.; Billi, M.; Contreras, M.; Larragubel, C.; Muñoz, A.; Smith, P.; Urquiza, A.; Vargas, M.; Videla, J.; Winckler, P. | 2020 | Agua y Extremos; Ciudades Resilientes | ||||||||||
| Hidden welfare effects of tree plantations | Environment and Development Economics | Anriquez, G.; Toledo, G.; Arriagada, R. | 2020 | Cambio de Uso de Suelo | 10.1017/S1355770X20000303 | https://www.cambridge.org/core/journals/environment-and-development-economics/article/abs/hidden-welfare-effects-of-tree-plantations/4DB425A678F2953DDD70811368899CE4#authors-details | 151-168 | Vol: 26 Issue: 2 | 1355-770X, 1469-4395 | Thomson Reuters ISI (SSCI) | English | Subsidies to promote tree plantations have been questioned because of negative impacts of the forestry industry. Quantitative evidence on the socioeconomic impacts of afforestation subsidies or of tree plantations is elusive, mainly due to data scarcity. We assess the overall impact of a tree plantation subsidy in Chile, using our original 20-year panel dataset that includes small area estimates of poverty and the subsidy assignment at the census-district scale. We show that forestry subsidies – on average – in fact, do increase poverty. More specifically, using difference in difference with matching techniques, and instrumental variables approaches, we show that there is an increase of about 2 per cent in the poverty rate of treated localities. We identify employment as a causal mechanism explaining this finding, since we found a negative effect of tree plantations on employment, and therefore, on poverty. We suggest reassessment of the distributional effects of the forest subsidy and forestry industry. | |
| Influence of coastal upwelling on micro-phytoplankton variability at Valparaíso Bay (~33ºS), Central Chile | Revista de Biología Marina y Oceanografía | Aparicio-Rizzo, P.; Masotti, I.; Landaeta, M. | 2020 | Zonas Costeras | 10.22370/rbmo.2020.55.1.2353 | https://revistas.uv.cl/index.php/rbmo/article/view/2353 | 11 | Vol: 55 Issue: 1 | 0718-1957, 0717-3326 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | In this work 10 years of data (1986-1996) from a fixed station located in the northern part of Valparaíso Bay (33º00’S; 71º35’W) were analysed to study the influence of coastal upwelling activity on the temporal variation of micro-phytoplankton (20-200 μm) and their relationship with oceanographic conditions. The upwelling activity at the bay was associated to semi-annual wind regime with an intensification of upwelling-favourable S-SW winds from September to March followed by a decrease and the occurrence of downwelling events from April to August. Oceanographic conditions showed the ascent of cold, nutrient-rich salty water in spring (September-November). However, during summertime under highest upwelling index, thermal stratification conditions were registered. This stratification might be associated to either the solar radiation or the presence of an upwelling shadow area in the bay. The upwelling period had the highest micro-phytoplankton abundance mainly dominated by diatoms. This period was associated with an increase in biomass and richness in the bay. Meanwhile during non-upwelling period —under homogenous conditions of temperature, salinity and nutrients— an increase in diversity (but low abundance and richness) associated to dinoflagellates and silicoflagellates was noted. Therefore, the results suggest the presence of a bi-modal regime of micro-phytoplankton in the bay in response to changes in oceanographic conditions related to local wind forcing and mixing/stratification. |
| Extreme Drought Affects Visitation and Seed Set in a Plant Species in the Central Chilean Andes Heavily Dependent on Hummingbird Pollination | Plants | Arroyo, M.; Robles, V.; Tamburrino, Í.; Martínez-Harms, J.; Garreaud, R.; Jara-Arancio, P.; Pliscoff, P.; Copier, A.; Arenas, J.; Keymer, J.; Castro, K. | 2020 | Agua y Extremos | 10.3390/plants9111553 | https://www.mdpi.com/2223-7747/9/11/1553 | 1553 | Vol: 9 Issue: 11 | 2223-7747 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Rising temperatures and increasing drought in Mediterranean-type climate areas are expected to affect plant–pollinator interactions, especially in plant species with specialised pollination. Central Chile experienced a mega drought between 2010 and 2020 which reached an extreme in the austral summer of 2019–2020. Based on intensive pollinator sampling and floral studies we show that the subalpine form of Mutisia subulata (Asteraceae) is a specialised hummingbird-pollinated species. In a two-year study which included the severest drought year, we quantified visitation frequency, flower-head density, flower-head visitation rates, two measures of floral longevity, nectar characteristics and seed set and monitored climatic variables to detect direct and indirect climate-related effects on pollinator visitation. Flower-head density, nectar standing crop and seed set were significantly reduced in the severest drought year while nectar concentration increased. The best model to explain visitation frequency included flower-head density, relative humidity, temperature, and nectar standing crop with highly significant effects of the first three variables. Results for flower-head density suggest hummingbirds were able to associate visual signals with reduced resource availability and/or were less abundant. The negative effect of lower relative humidity suggests the birds were able to perceive differences in nectar concentration. Reduced seed set per flower-head together with the availability of far fewer ovules in the 2019–2020 austral summer would have resulted in a major reduction in seed set. Longer and more intense droughts in this century could threaten local population persistence in M. subulata. |
| RF-MEP: A novel Random Forest method for merging gridded precipitation products and ground-based measurements | Remote Sensing of Environment | Baez-Villanueva, O.; Zambrano-Bigiarini, M.; Beck, H.; McNamara, I.; Ribbe, L.; Nauditt, A.; Birkel, C.; Verbist, K.; Giraldo-Osorio, J.; Xuan Thinh, N. | 2020 | Agua y Extremos | 10.1016/j.rse.2019.111606 | https://linkinghub.elsevier.com/retrieve/pii/S0034425719306261 | 111606 | Vol: 239 | 00344257 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The accurate representation of spatio-temporal patterns of precipitation is an essential input for numerous environmental applications. However, the estimation of precipitation patterns derived solely from rain gauges is subject to large uncertainties. We present the Random Forest based MErging Procedure (RF-MEP), which combines information from ground-based measurements, state-of-the-art precipitation products, and topography-related features to improve the representation of the spatio-temporal distribution of precipitation, especially in data-scarce regions. RF-MEP is applied over Chile for 2000—2016, using daily measurements from 258 rain gauges for model training and 111 stations for validation. Two merged datasets were computed: RF-MEP3P (based on PERSIANN-CDR, ERA-Interim, and CHIRPSv2) and RF-MEP5P (which additionally includes CMORPHv1 and TRMM 3B42v7). The performances of the two merged products and those used in their computation were compared against MSWEPv2.2, which is a state-of-the-art global merged product. A validation using ground-based measurements was applied at different temporal scales using both continuous and categorical indices of performance. RF-MEP3P and RF-MEP5P outperformed all the precipitation datasets used in their computation, the products derived using other merging techniques, and generally outperformed MSWEPv2.2. The merged P products showed improvements in the linear correlation, bias, and variability of precipitation at different temporal scales, as well as in the probability of detection, the false alarm ratio, the frequency bias, and the critical success index for different precipitation intensities. RF-MEP performed well even when the training dataset was reduced to 10% of the available rain gauges. Our results suggest that RF-MEP could be successfully applied to any other region and to correct other climatological variables, assuming that ground-based data are available. An R package to implement RF-MEP is freely available online at https://github.com/hzambran/RFmerge. |
| Sobrenaturaleza mapuche: extractivismo, seres no humanos y miedo en el Centro Sur de Chile | Revista Austral de Ciencias Sociales | Bahamonde, P.; Mellado, M.; Blanco-Wells, G. | 2020 | 10.4206/rev.austral.cienc.soc.2020n38-01 | http://revistas.uach.cl/index.php/racs/article/view/6139 | 7-30 | Vol: 2020 Issue: 38 | 0718-1795 | Not indexed | Spanish | This work focuses on understanding the effects produced in Mapuche territories with the arrival of extractive projects in the field of energy production. From a political ontology perspective, and through an ethnographic methodology, we analyze the case of the Neltume Hydroelectric Project located in the Panguipulli commune (Region of Los Ríos, south of Chile). Rethinking critically the approaches of the Brazilian anthropologist Eduardo Viveiros de Castro, in the light of our field findings, we argue that the territories intervened -from certain transgressive actions- are comprised of “supernatural” contexts. This entails a change in the relationship between a set of non-human entities regarding to humans, characterized by the belligerence and anger of the former against the lack of protection and the fear of the latter. | ||
| A multiscale analysis of the tornadoes of 30–31 May 2019 in south-central Chile | Atmospheric Research | Barrett, B.; Marin, J.; Jacques-Coper, M. | 2020 | Zonas Costeras | 10.1016/j.atmosres.2019.104811 | https://linkinghub.elsevier.com/retrieve/pii/S0169809519310683 | 104811 | Vol: 236 | 01698095 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | On 30 and 31 May 2019, tornadoes occurred in the cities of Los Angeles and Talcahuano/Concepción in south-central Chile, in a region where tornado activity is not common. The main goal of this study was to analyze these tornadoes across multiple scales: synoptic, mesoscale, and subseasonal. On the synoptic scale, the tornadoes were associated with an anomalous 500-hPa trough and associated surface cyclone to the west of Chile. A strong (20+ m s−1) low-level jet accompanied this trough, potentially enhanced by flow blocking by the Andes. A relatively warm and saturated surface layer combined with cold upper-level temperatures in the trough to yield 200–500 J kg−1 of CAPE on both days. This CAPE was accompanied by high levels of both deep-layer and low-level shear. Storm motions inferred by lightning swaths and GOES-IR imagery, along with estimates of storm motion and updraft helicity from a high-resolution WRF simulation, suggested this CAPE-shear combination was sufficient for the tornadic thunderstorms to be supercells. Finally, anomalies of sea level pressure, 500-hPa height, and surface dew point temperature from 27 to 31 May 2019 resembled long-term composite anomalies for MJO phases 1 and 2, suggesting a subseasonal link between the extreme event in Chile and convection in the tropics. |
| Late Quaternary climatic variability in northern Patagonia, Argentina, based on δ18O of modern and fossil shells of Amiantis purpurata (Bivalvia, Veneridae) | Palaeogeography, Palaeoclimatology, Palaeoecology | Bayer, S.; Beierlein, L.; Morán, G.; Doldán, M.; Morsan, E.; Brey, T.; Mackensen, A.; Farías, L.; García, G.; Gordillo, S. | 2020 | Zonas Costeras | 10.1016/j.palaeo.2020.110012 | https://linkinghub.elsevier.com/retrieve/pii/S0031018220304570 | 110012 | Vol: 560 | 00310182 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Amiantis purpurata is a common warm-temperate water bivalve species distributed from southern Brazil to northern Patagonia, Argentina, which has a rich and well preserved fossil record in the San Matías Gulf (SMG) dating back to the late Quaternary. This study aims to establish A. purpurata shells as a new palaeoarchive of past marine conditions in South America. We compared the stable oxygen and carbon profiles (δ18Oshell; δ13Cshell) of eleven specimens of A. purpurata from different geological times (modern, Late Holocene and interglacial Late Pleistocene), and additionally present in situ oxygen isotope values of seawater within SMG (δ18Owater). Using both sets of information, we calculated and reconstructed palaeowater temperatures for the Late Holocene and compared them to modern water temperatures. Our findings indicate that A. purpurata records past environmental parameters such as water temperatures on a seasonal scale and can therefore be considered a suitable candidate for future palaeoenvironmental reconstructions in Northern Patagonia. This study is the first step towards further stable isotope analyses on fossil A. purpurata shells, which will show whether and if so, to what extent, important global climate events such as the Neoglacial (Early Holocene), the Hypsithermal (Middle Holocene) and the Little Ice Age (Late Holocene) occurred in South America. |
| Bias correction of global high-resolution precipitation climatologies using streamflow observations from 9372 catchments | Journal of Climate | Beck, H.; Wood, E.; McVicar, T.; Zambrano-Bigiarini, M.; Alvarez-Garreton, C.; Baez-Villanueva, O.; Sheffield, J.; Karger, D. | 2020 | Agua y Extremos | 10.1175/JCLI-D-19-0332.1 | http://journals.ametsoc.org/doi/10.1175/JCLI-D-19-0332.1 | 1299-1315 | Vol: 33 Issue: 4 | 0894-8755 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | We introduce a set of global high-resolution (0.05 ◦ ) precipitation ( P) climatologies corrected for bias using streamflow ( Q) observations from 9372 stations worldwide. For each station, we inferred the “true” long-term P using a Budyko curve, an empirical equation relating long-term P, Q, and potential evaporation. We subsequently calculated long-term bias correction factors for three state-of-the-art P climatologies (WorldClim V2, CHELSA V1.2, and CHPclim V1), after which we used random forest regression to produce global gap-free bias correction maps for the climatologies. Monthly climatological bias correction factors were calculated by disaggregating the long-term bias correction factors based on gauge catch efficiencies. We found that all three climatologies systematically underestimate P over parts of all major mountain ranges globally, despite the explicit consideration of orography in the production of each climatology. Additionally, all climatologies underestimate P at latitudes > 60 ◦ N, likely due to gauge under-catch. Exceptionally high long-term correction factors ( > 1 .5) were obtained for all three climatologies in Alaska, High Mountain Asia, and Chile — regions characterized by marked elevation gradients, sparse gauge networks, and significant snowfall. Using the bias-corrected WorldClim V2, we demonstrated that other widely used P datasets (GPCC V2015, GPCP V2.3, and MERRA-2) severely underestimate P over Chile, the Himalayas, and along the Pacific coast of North America. Mean P for the global land surface based on the bias-corrected WorldClim V2 is 862 mm yr −1 (a 9.4 % increase over the original WorldClim V2). The annual and monthly bias-corrected P climatologies have been released as the Precipitation Bias CORrection (PBCOR) dataset — downloadable via www.gloh2o.org/pbcor . |
| Gobernanza policéntrica para la resiliencia al cambio climático: análisis legislativo comparado y Ley Marco de Cambio en Chile | Estudios Públicos | Billi, M.; Delgado, V.; Jiménez, G.; Morales, B.; Neira, C.; Silva, M.; Urquiza, A. | 2020 | 10.38178/07183089/1028191015 | https://www.estudiospublicos.cl/index.php/cep/article/view/1937 | 7-53 | Issue: 160 | 0718-3089, 0716-1115 | Erih, Latindex | Una gobernanza capaz de dar respuestas eficaces, proactivas y adaptativas frente al cambio climático requiere hacer frente al menos a tres órdenes de desafíos: (1) deberá prestar atención a las particularidades de los contextos locales, sin perder de vista interdependencias globales; (2) deberá coordinar de manera coherente una multiplicidad de perspectivas y actores autónomos; y (3) deberá fomentar la innovación y el aprendizaje mientras mantiene un grado mínimo de estabilidad necesaria para realizar predicciones y tomar decisiones. El artículo argumenta que el enfoque de gobernanza policéntrica, especialmente en su interpretación sistémica, ofrece respuestas efectivas para estos tres desafíos, y emplea dicho enfoque para evaluar las actuales normativas de cambio climático, por medio de un análisis comparado de legislaciones internacionales, y de un estudio de caso del Proyecto de Ley Marco de Cambio Climático de Chile. Se finaliza identificando oportunidades y retos, así como proponiendo recomendaciones de política pública. | |||
| Hydrological Processes Special Issue “Hydrological processes across climatic and geomorphological gradients of Latin America” | Hydrological Processes | Birkel, C.; Moore, G.; Zambrano‐Bigiarini, M. | 2020 | Agua y Extremos | 10.1002/hyp.13648 | https://onlinelibrary.wiley.com/doi/abs/10.1002/hyp.13648 | 156-158 | Vol: 34 Issue: 2 | 0885-6087, 1099-1085 | Thomson Reuters ISI (SCIE) | English | In this special issue of Hydrological Processes, we showcase the variety of ongoing research in catchments of the hydrometeorological, geomorphological, and biogeographical megadiverse region of Latin America and the Caribbean (LAC). The papers of this special issue address hydrological processes that regulate storage, mixing, and fluxes of water and solutes from the driest Atacama Desert in Chile (annual precipitation lower than 10 mm in some places) to the wettest mountainous areas of Central America (annual rainfall up to 8,000 mm), including the richest biodiversity on Earth present in the Amazon. Not only are tropical rainforest ecosystems poorly represented in hydrologic research, the LAC contains a myriad of unique lowland to montane ecosystems across the climate gradient that also includes snow and ice processes. Opportunities to advance understanding of how vegetation and landforms redistribute moisture abound in the remote reaches of Latin America. Such modulation of the hydrological cycle by vegetation and large‐scale connecting driving forces of rainfall generating moisture transport is the topic of the contributions briefly introduced in the following section. There are three major transcending themes covered in this special issue: 1) hydrological processes across climate gradients, 2) unique ecosystems with limited hydrological research, 3) effects of land use change on hydrology. |
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| Agencias veladas y apertura ontológica: desafíos posthumanistas de la teoría social contemporánea. / Veiled agencies and ontological opening: post-humanist challenges of contemporary social theory. | Utopía y Praxis Latinoamericana | Blanco, G.; Iriarte, P.; Bravo, J. | 2020 | Ciudades Resilientes | 10.5281/zenodo.4110851 | https://produccioncientificaluz.org/index.php/utopia/article/view/34230 | 28-41 | Vol: 25 Issue: 9 | 2477-9555 | Not indexed | Spanish | Considerando el debate abierto por el posthumanismo, proponemos la noción de agencias veladas para dar cuenta de la operación a partir de la cual la teoría social de corte humanista ha silenciado y ocultado la capacidad de agencia tanto de entidades no-humanas como también de grupos humanos específicos. ¿Cómo desmarcarse de este proceso de ocultamiento para devolver la acción y el sentido a los materiales, los cuerpos y sus relaciones? El artículo aboga por una praxis investigativa que, profundizando los aportes del posthumanismo, genere una apertura ontológica con consecuencias éticas y científicas relevantes. | |
| Recent Near-surface Temperature Trends in the Antarctic Peninsula from Observed, Reanalysis and Regional Climate Model Data | Advances in Atmospheric Sciences | Bozkurt, D.; Bromwich, D.; Carrasco, J.; Hines, K.; Maureira, J.; Rondanelli, R. | 2020 | Agua y Extremos; Zonas Costeras | 10.1007/s00376-020-9183-x | http://link.springer.com/10.1007/s00376-020-9183-x | 477-493 | Vol: 37 Issue: 5 | 0256-1530, 1861-9533 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | This study investigates the recent near-surface temperature trends over the Antarctic Peninsula. We make use of available surface observations, ECMWF’s ERA5 and its predecessor ERA-Interim, as well as numerical simulations, allowing us to contrast different data sources. We use hindcast simulations performed with Polar-WRF over the Antarctic Peninsula on a nested domain configuration at 45 km (PWRF-45) and 15 km (PWRF-15) spatial resolutions for the period 1991-2015. In addition, we include hindcast simulations of KNMI-RACMO21P obtained from the CORDEX-Antarctica domain (~50 km) for further comparisons. Results show that there is a marked windward warming trend except during summer. This windward warming trend is particularly notable in the autumn season and likely to be associated with the recent deepening of the Amundsen/Bellingshausen Sea low and warm advection towards the Antarctic Peninsula. On the other hand, an overall summer cooling is characterized by the strengthening of the Weddell Sea low as well as an anticyclonic trend over the Amundsen Sea accompanied by northward winds. The persistent cooling trend observed at the Larsen Ice Shelf station is not captured by ERA-Interim, whereas hindcast simulations indicate that there is a clear pattern of windward warming and leeward cooling. Furthermore, larger temporal correlations and lower differences exhibited by PWRF-15 illustrate the existence of the added value in the higher spatial resolution simulation. |
| Anaerobic oxidation of methane and associated microbiome in anoxic water of Northwestern Siberian lakes | Science of The Total Environment | Cabrol, L.; Thalasso, F.; Gandois, L.; Sepulveda-Jauregui, A.; Martinez-Cruz, K.; Teisserenc, R.; Tananaev, N.; Tveit, A.; Svenning, M.; Barret, M. | 2020 | Cambio de Uso de Suelo | 10.1016/j.scitotenv.2020.139588 | https://linkinghub.elsevier.com/retrieve/pii/S0048969720331053 | 139588 | Vol: 736 | 00489697 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Arctic lakes emit methane (CH4) to the atmosphere. The magnitude of this flux could increase with permafrost thaw but might also be mitigated by microbial CH4 oxidation. Methane oxidation in oxic water has been extensively studied, while the contribution of anaerobic oxidation of methane (AOM) to CH4 mitigation is not fully understood. We have investigated four Northern Siberian stratified lakes in an area of discontinuous permafrost nearby Igarka, Russia. Analyses of CH4 concentrations in the water column demonstrated that 60 to 100% of upward diffusing CH4 was oxidized in the anoxic layers of the four lakes. A combination of pmoA and mcrA gene qPCR and 16S rRNA gene metabarcoding showed that the same taxa, all within Methylomonadaceae and including the predominant genus Methylobacter as well as Crenothrix, could be the major methane-oxidizing bacteria (MOB) in the anoxic water of the four lakes. Correlation between Methylomonadaceae and OTUs within Methylotenera, Geothrix and Geobacter genera indicated that AOM might occur in an interaction between MOB, denitrifiers and iron-cycling partners. We conclude that MOB within Methylomonadaceae could have a crucial impact on CH4 cycling in these Siberian Arctic lakes by mitigating the majority of produced CH4 before it leaves the anoxic zone. This finding emphasizes the importance of AOM by Methylomonadaceae and extends our knowledge about CH4 cycle in lakes, a crucial component of the global CH4 cycle. |
| Climate impacts of the El Niño–Southern Oscillation on South America | Nature Reviews Earth & Environment | Cai, W.; McPhaden, M.; Grimm, A.; Rodrigues, R.; Taschetto, A.; Garreaud, R.; Dewitte, B.; Poveda, G.; Ham, Y.; Santoso, A.; Ng, B.; Anderson, W.; Wang, G.; Geng, T.; Jo, H.; Marengo, J.; Alves, L.; Osman, M.; Li, S.; Wu, L.; Karamperidou, C.; Takahashi, K.; Vera, C. | 2020 | Agua y Extremos | 10.1038/s43017-020-0040-3 | http://www.nature.com/articles/s43017-020-0040-3 | 215-231 | Vol: 1 Issue: 4 | 2662-138X | Thomson Reuters ISI (SCIE) | English | The climate of South America (SA) has long held an intimate connection with El Niño, historically describing anomalously warm sea-surface temperatures off the coastline of Peru. Indeed, throughout SA, precipitation and temperature exhibit a substantial, yet regionally diverse, relationship with the El Niño–Southern Oscillation (ENSO). For example, El Niño is typically accompanied by drought in the Amazon and north-eastern SA, but flooding in the tropical west coast and south-eastern SA, with marked socio-economic effects. In this Review, we synthesize the understanding of ENSO teleconnections to SA. Recent efforts have sought improved understanding of ocean–atmosphere processes that govern the impact, inter-event and decadal variability, and responses to anthropogenic warming. ENSO’s impacts have been found to vary markedly, affected not only by ENSO diversity, but also by modes of variability within and outside of the Pacific. However, while the understanding of ENSO–SA relationships has improved, with implications for prediction and projection, uncertainty remains in regards to the robustness of the impacts, inter-basin climate interactions and interplay with greenhouse warming. A coordinated international effort is, therefore, needed to close the observational, theoretical and modelling gaps currently limiting progress, with specific efforts in extending palaeoclimate proxies further back in time, reducing systematic model errors and improving simulations of ENSO diversity and teleconnections. © 2020, Springer Nature Limited. | |
| RedPE (2020). Vulnerabilidad Energética Territorial: Desigualdad más allá del hogar | Calvo, R.; Amigo, C.; Billi, M.; Fleischmann, M.; Urquiza, A. | 2020 | Ciudades Resilientes | http://redesvid.uchile.cl/pobreza-energetica/wp-content/uploads/2020/11/VF_Informe-VET.pdf | La energía es uno de los recursos fundamentales para el desarrollo económico y humano de las personas y de las sociedades contemporáneas. Por un lado, el acceso a una energía de calidad tiene consecuencias en el acceso a educación, empleabilidad, alimentación e incluso en la salud de las personas (Liddell & Morris, 2010; Nadimi & Tokimatsu, 2018; Robić & Ančić, 2018; Thomson, Snell & Bouzarovski, 2017). Por otro lado, un sistema energético estable y de calidad habilita el desarrollo económico al permitir la implementación de tecnologías modernas de producción, ampliar el uso de tecnologías de información y comunicación, entre otros (Bhatia & Angelou, 2015; Naciones Unidas, 2018; Practical Action, 2017). En la actualidad, los sistemas energéticos se encuentran tensionados por dos fenómenos paralelos y relacionados entre sí, sobre todo en los países en vías al desarrollo: el cambio climático y la necesidad de una transición energética. En primer lugar, el cambio climático ha puesto en evidencia los efectos negativos de una matriz energética basada mayoritariamente en combustibles fósiles, debido a los efectos de sus altas emisiones de Gases de Efecto Invernadero (GEI). A nivel global, la generación de energía contribuye con un 30% de las emisiones totales de GEI, mientras que el sector energético contribuye un 73% de las emisiones totales (incluyendo transporte, electricidad y calefacción, edificios, manufacturas y construcción, emisiones fugitivas y combustión de otros combustibles)1 . Por lo tanto, la matriz de generación de energía debiese transitar hacia la descarbonización en las siguientes décadas si se desea mantener el calentamiento global por bajo los 1.5ºC y adaptarse a los límites planetarios (Falk et al., 2019; IPCC, 2019a; Rockström et al., 2009). Esta radical transformación debiese ser capaz, al mismo tiempo, de asegurar un suministro energético adecuado al desarrollo económico y humano, adaptándose a las nuevas condiciones climáticas y tecnológicas, necesarias para la transición a una matriz energética renovable. |
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| ARCLIM Anexo: Piloto Riesgo integrado. Cuenca del río Cachapoal- Región de O’Higgins en ARClim – Atlas de Riesgo Climático | Calvo, R.; Navea, J.; Fleishmann, M.; Barrera, V.; Peña, D.; Billi, M.; Urquiza, A. | 2020 | Ciudades Resilientes | ||||||||||
| Transformation of social capital during and after a disaster event: the cases Chañaral and Diego de Almagro, Atacama Region, Chile | Natural Hazards | Castro-Correa, C.; Aldunce Ide, P.; Wyndham Vásquez, K.; Mena Maldonado, D.; Pérez Tello, S. | 2020 | Agua y Extremos | 10.1007/s11069-020-04091-9 | http://link.springer.com/10.1007/s11069-020-04091-9 | 2427-2440 | Vol: 103 Issue: 2 | 0921-030X, 1573-0840 | Thomson Reuters ISI (SCIE) | English | This article analyzes the impact of socio-natural disasters on social capital at a local level, studying the cases of the communities of Chañaral and Diego de Almagro after the flooding and mudflow disasters of 2015. Specifically, we explore different dynamics of social capital in the response to the emergency, recovery and reconstruction stages, exploring its role in strengthening adaptation and resilience capacities for disaster risk reduction. Through the qualitative analysis of semi-structured interviews with survivors of the disaster, we explore the nature and role of social trust and its influence on the formation and consolidation of bonding, bridging and linking social capital in the context of disaster is analyzed. The results unpack the role of social capital in the response, recovery and reconstruction processes after a disaster event, which directly influences the development and consolidation of capacities for community adaptation, highlighting the role of trust for the strengthening of resilience. Likewise, the article provides details about the role of institutions and authorities in the consolidation of bridging and linking social capital, which requires the generation of formal and fluid communication channels that allow for the creation of trust, not only among the members of the community, but between the community and the institutions and authorities. | |
| First snow, glacier and groundwater contribution quantification in the upper Mendoza River basin using stable water isotopes | Isotopes in Environmental and Health Studies | Crespo, S.; Fernandoy, F.; Cara, L.; Klarian, S.; Lavergne, C. | 2020 | Agua y Extremos | 10.1080/10256016.2020.1797713 | https://www.tandfonline.com/doi/full/10.1080/10256016.2020.1797713 | 566-585 | Vol: 56 Issue: 5-6 | 1025-6016, 1477-2639 | Thomson Reuters ISI (SCIE) | English | The Mendoza River streamflow, South America (∼32 °S), derives almost exclusively from winter snow precipitation falling in the Andes. Almost 70% of the water feeding the river originates in the Cordillera Principal geological province. In addition to the snow that precipitates in this area, there are 951 cryoforms providing meltwater to the upper catchment. Given the high inter-annual variability of snowfall and the megadrought affecting the region since 2010, it is crucial to quantify the contribution from different water sources buffering the Mendoza River runoff. Combining instrumental records of streamflow from glaciers and rivers, meteorological data, remote sensing of snow-covered areas and ionic and stable isotope analysis of different water sources, this study attempts to understand the hydrological contribution of different water sources to the basin. We demonstrated for the first time the relevance of different water sources in addition to snow in a dry period. During the melting season, 65% of the streamwaters originated from the glaciers (i.e. 50 and 15% from glaciers and rock glaciers, respectively), representing a higher proportion compared to snowmelt (17%). Groundwater input showed relatively large contributions, averaging 18%. This work offers information to develop adaptation strategies for future climate change scenarios in the region. | |
| Where Does the Chilean Aconcagua River Come from? Use of Natural Tracers for Water Genesis Characterization in Glacial and Periglacial Environments | Water | Crespo, S.; Lavergne, C.; Fernandoy, F.; Muñoz, A.; Cara, L.; Olfos-Vargas, S. | 2020 | Agua y Extremos | 10.3390/w12092630 | https://www.mdpi.com/2073-4441/12/9/2630 | 2630 | Vol: 12 Issue: 9 | 2073-4441 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Aconcagua river basin (Chile, 32 °S) has suffered the effects of the megadrought over the last decade. The severe snowfall deficiency drastically modified the water supply to the catchment headwaters. Despite the recognized snowmelt contribution to the basin, an unknown streamflow buffering effect is produced by glacial, periglacial and groundwater inputs, especially in dry periods. Hence, each type of water source was characterized and quantified for each season, through the combination of stable isotope and ionic analyses as natural water tracers. The δ18O and electric conductivity were identified as the key parameters for the differentiation of each water source. The use of these parameters in the stable isotope mixing “simmr” model revealed that snowmelt input accounted 52% in spring and only 22–36% during the rest of the year in the headwaters. While glacial supply contributed up to 34%, both groundwater and periglacial exhibited a remarkable contribution around 20% with some seasonal variations. Downstream, glacial contribution averaged 15–20%, groundwater seasonally increased up to 46%, and periglacial input was surprisingly high (i.e., 14–21%). The different water sources contribution quantification over time for the Aconcagua River reported in this work provides key information for water security in this territory. |
| Mathematical Modeling for 2D Light--Sheet Fluorescence Microscopy image reconstruction | Inverse Problems | Cueva, E.; Courdurier, M.; Osses, A.; Castañeda, V.; Palacios, B.; Härtel, S. | 2020 | Ciudades Resilientes | 10.1088/1361-6420/ab80d8 | https://iopscience.iop.org/article/10.1088/1361-6420/ab80d8 | 075005 | Vol: 36 Issue: 7 | 0266-5611, 1361-6420 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | We study an inverse problem for light sheet fluorescence microscopy (LSFM), where the density of fluorescent molecules needs to be reconstructed. Our first step is to present a mathematical model to describe the measurements obtained by an optic camera during an LSFM experiment. Two meaningful stages are considered: excitation and fluorescence. We propose a paraxial model to describe the excitation process which is directly related with the Fermi pencil-beam equation. For the fluorescence stage, we use the transport equation to describe the transport of photons towards the detection camera. For the mathematical inverse problem that we obtain after the modeling, we present a uniqueness result, recasting the problem as the recovery of the initial condition for the heat equation in $\mathbb{R}{\times}\left(0,\infty \right)$ from measurements in a space–time curve. Additionally, we present numerical experiments to recover the density of the fluorescent molecules by discretizing the proposed model and facing this problem as the solution of a large and sparse linear system. Some iterative and regularized methods are used to achieve this objective. The results show that solving the inverse problem achieves better reconstructions than the direct acquisition method that is currently used. |
| Integrating conflict, lobbying, and compliance to predict the sustainability of natural resource use | Ecology and Society | Cusack, J.; Duthie, A.; Minderman, J.; Jones, I.; Pozo, R.; Rakotonarivo, O.; Redpath, S.; Bunnefeld, N. | 2020 | Cambio de Uso de Suelo | 10.5751/ES-11552-250213 | https://www.ecologyandsociety.org/vol25/iss2/art13/ | art13 | Vol: 25 Issue: 2 | 1708-3087 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Predictive models are sorely needed to guide the management of harvested natural resources worldwide, yet existing frameworks fail to integrate the dynamic and interacting governance processes driving unsustainable use. We developed a new framework in which the conflicting interests of three key stakeholders are modeled: managers seeking sustainability, users seeking increases in harvest quota, and conservationists seeking harvest restrictions. Our model allows stakeholder groups to influence management decisions and illegal harvest through flexible functions that reflect widespread lobbying and noncompliance processes. Decision making is modeled through the use of a genetic algorithm, which allows stakeholders to respond to a dynamic social-ecological environment to satisfy their goals. To provide the critical link between conceptual and empirical approaches, we compare predictions from our model against data on 206 harvested terrestrial species from the IUCN Red List. We show that, although lobbying for a ban on resource use can offset low levels of noncompliance, such bias leads to an increased risk of extinction when noncompliance (and therefore illegal harvesting) is high. Management decisions unaffected by lobbying, combined with high rule compliance, resulted in more sustainable resource use. Model predictions were strongly reflected in our analysis of harvested IUCN species, with 81% of those classified under regulated harvest and high compliance showing stable or increasing population trends. Our results highlight the fine balance between maintaining compliance and biasing decisions in the face of lobbying. They also emphasize the urgent need to quantify lobbying and compliance processes across a range of natural resources. Overall, our work provides a holistic and versatile approach to addressing complex social processes underlying the mismanagement of natural resources. © 2020 by the author(s). |
| Connection between Antarctic Ozone and Climate: Interannual Precipitation Changes in the Southern Hemisphere | Atmosphere | Damiani, A.; Cordero, R.; Llanillo, P.; Feron, S.; Boisier, J.; Garreaud, R.; Rondanelli, R.; Irie, H.; Watanabe, S. | 2020 | Agua y Extremos; Zonas Costeras | 10.3390/atmos11060579 | https://www.mdpi.com/2073-4433/11/6/579 | 579 | Vol: 11 Issue: 6 | 2073-4433 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | In this study, we explored the connection between anomalies in springtime Antarctic ozone and all-year precipitation in the Southern Hemisphere by using observations from 1960–2018 and coupled simulations for 1960–2050. The observations showed that this correlation was enhanced during the last several decades, when a simultaneously increased coupling between ozone and Southern Annular Mode (SAM) anomalies became broader, covering most of the following summer and part of the previous winter. For eastern Australia, the ozone–precipitation connection shows a greater persistence toward the following summer than for other regions. On the other hand, for South America, the ozone–precipitation correlation seems more robust, especially in the early summer. There, the correlation also covers part of the previous winter, suggesting that winter planetary waves could affect both parameters. Further, we estimated the sensitivity of precipitation to changes in Antarctic ozone. In both observations and simulations, we found comparable sensitivity values during the spring–summer period. Overall, our results indicate that ozone anomalies can be understood as a tracer of stratospheric circulation. However, simulations indicate that stratospheric ozone chemistry still contributes to strengthening the interannual relationship between ozone and surface climate. Because simulations reproduced most of the observed connections, we suggest that including ozone variability in seasonal forecasting systems can potentially improve predictions. |
| Holocene dust dynamics: Introduction to the special issue | The Holocene | De Vleeschouwer, F.; Stuut, J.; Lambert, F. | 2020 | Ciudades Resilientes | 10.1177/0959683619892670 | http://journals.sagepub.com/doi/10.1177/0959683619892670 | 489-491 | Vol: 30 Issue: 4 | 0959-6836, 1477-0911 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | This article is a brief introduction to the Special Issue on Holocene Dust Dynamics, which brings together recent research on a key aspect of the Earth’s changing climate through its effects on radiative balance, cloud cover and biogeochemical cycles. The aim of the Special Issue is to contribute to a better understanding of the role of dust aerosols by analysing the evolution and climatic impact of atmospheric dust over long and short timescales within the Holocene. Here, we introduce the rationale behind the Special Issue and the eight research papers, which include long-term records of dust deposition from different types of natural archive (e.g. peatlands, ice, loess and lake sediments) as well as present-day multi-annual dust trap records and process studies from various climatic regimes that have global implications. |
| Significant decrease of photovoltaic power production by aerosols. The case of Santiago de Chile | Renewable Energy | Del Hoyo, M.; Rondanelli, R.; Escobar, R. | 2020 | Zonas Costeras | 10.1016/j.renene.2019.10.005 | https://linkinghub.elsevier.com/retrieve/pii/S096014811931496X | 1137-1149 | Vol: 148 | 0960-1481 | Thomson Reuters ISI (SCIE) | English | Santiago de Chile frequently suffers from atmospheric pollution that contributes to the decrease of solarirradiance on the surface, leading to losses in the energy output of photovoltaic systems. In this study, asimple model is used to estimate the effect of aerosols on the solar irradiance over the city throughoutthe year, using as input AERONET sunphotometer data and other in-situ measurements. The results showreductions of 3.5% and 14.1% for global horizontal and direct normal irradiance respectively and an in-crease of 35.4% for diffuse horizontal irradiance between the actual condition in Santiago and a hypo-thetical atmosphere free of aerosols. These effects translate approximately to an annual difference in theenergy output of 7.2% and 8.7% for monocrystalline and amorphous silicon PV technologies respec-tively, and an annual difference of 16.4% for a CPV technology, showing that aerosols can have a sig-nificant effect on the photovoltaic energy production. | |
| Trends and emissions of six perfluorocarbons in the Northern Hemisphere and Southern Hemisphere | Atmospheric Chemistry and Physics | Droste, E.; Adcock, K.; Ashfold, M.; Chou, C.; Fleming, Z.; Fraser, P.; Gooch, L.; Hind, A.; Langenfelds, R.; Leedham Elvidge, E.; Mohd Hanif, N.; O'Doherty, S.; Oram, D.; Ou-Yang, C.; Panagi, M.; Reeves, C.; Sturges, W.; Laube, J. | 2020 | Ciudades Resilientes | 10.5194/acp-20-4787-2020 | https://www.atmos-chem-phys.net/20/4787/2020/ | 4787-4807 | Vol: 20 Issue: 8 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Perfluorocarbons (PFCs) are potent greenhouse gases with global warming potentials up to several thousand times greater than CO2 on a 100-year time horizon. The lack of any significant sinks for PFCs means that they have long atmospheric lifetimes of the order of thousands of years. Anthropogenic production is thought to be the only source for most PFCs. Here we report an update on the global atmospheric abundances of the following PFCs, most of which have for the first time been analytically separated according to their isomers: c-octafluorobutane (c-C4F8), n-decafluorobutane (n-C4F10), n-dodecafluoropentane (n-C5F12), n-tetradecafluorohexane (n-C6F14), and n-hexadecafluoroheptane (n-C7F16). Additionally, we report the first data set on the atmospheric mixing ratios of perfluoro-2-methylpentane (i-C6F14). The existence and significance of PFC isomers have not been reported before, due to the analytical challenges of separating them. The time series spans a period from 1978 to the present. Several data sets are used to investigate temporal and spatial trends of these PFCs: time series of air samples collected at Cape Grim, Australia, from 1978 to the start of 2018; a time series of air samples collected between July 2015 and April 2017 at Tacolneston, UK; and intensive campaign-based sampling collections from Taiwan. Although the remote “background” Southern Hemispheric Cape Grim time series indicates that recent growth rates of most of these PFCs are lower than in the 1990s, we continue to see significantly increasing mixing ratios that are between 6 % and 27 % higher by the end of 2017 compared to abundances measured in 2010. Air samples from Tacolneston show a positive offset in PFC mixing ratios compared to the Southern Hemisphere baseline. The highest mixing ratios and variability are seen in air samples from Taiwan, which is therefore likely situated much closer to PFC sources, confirming predominantly Northern Hemispheric emissions for most PFCs. Even though these PFCs occur in the atmosphere at levels of parts per trillion molar or less, their total cumulative global emissions translate into 833 million metric tonnes of CO2 equivalent by the end of 2017, 23 % of which has been emitted since 2010. Almost two-thirds of the CO2 equivalent emissions within the last decade are attributable to c-C4F8, which currently also has the highest emission rates that continue to grow. Sources of all PFCs covered in this work remain poorly constrained and reported emissions in global databases do not account for the abundances found in the atmosphere. |
| Surface indicators are correlated with soil multifunctionality in global drylands | Journal of Applied Ecology | Eldridge, D.; Delgado‐Baquerizo, M.; Quero, J.; Ochoa, V.; Gozalo, B.; García‐Palacios, P.; Escolar, C.; García‐Gómez, M.; Prina, A.; Bowker, M.; Bran, D.; Castro, I.; Cea, A.; Derak, M.; Espinosa, C.; Florentino, A.; Gaitán, J.; Gatica, G.; Gómez‐González, S.; Ghiloufi, W.; Gutierrez, J.; Guzman, E... | 2020 | Cambio de Uso de Suelo | 10.1111/1365-2664.13540 | https://onlinelibrary.wiley.com/doi/abs/10.1111/1365-2664.13540 | 424-435 | Vol: 57 Issue: 2 | 0021-8901, 1365-2664 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Multiple ecosystem functions need to be considered simultaneously to manage and protect the many ecosystem services that are essential to people and their environments. Despite this, cost effective, tangible, relatively simple, and globally‐relevant methodologies to monitor in situ soil multifunctionality, i.e. the provision of multiple ecosystem functions by soils, have not been tested at the global scale. We combined correlation analysis and structural equation modelling to explore whether we could find easily measured, field‐based indicators of soil multifunctionality (measured using functions linked to the cycling and storage of soil carbon, nitrogen, and phosphorus). To do this, we gathered soil data from 120 dryland ecosystems from five continents. Two soil surface attributes measured in situ (litter incorporation and surface aggregate stability) were the most strongly associated with soil multifunctionality, even after accounting for geographic location and other drivers such as climate, woody cover, soil pH and soil electric conductivity. The positive relationships between surface stability and litter incorporation on soil multifunctionality was greater beneath the canopy of perennial vegetation than in adjacent, open areas devoid of vascular plants. The positive associations between surface aggregate stability and soil functions increased with increasing mean annual temperature. Synthesis and applications. Our findings demonstrate that a reduced suite of easily measured in situ soil surface attributes can be used as potential indicators of soil multifunctionality in drylands worldwide. These attributes, which relate to plant litter (origin, incorporation, cover), and surface stability, are relatively cheap and easy to assess with minimal training, allowing operators to sample many sites across widely varying climatic areas and soil types. The correlations of these variables are comparable to the influence of climate or soil, and would allow cost‐effective monitoring of soil multifunctionality under changing land use and environmental conditions. This would provide important information for evaluating the ecological impacts of land degradation, desertification and climate change in drylands worldwide. |
| Hydroclimate of the Andes Part I: Main Climatic Features | Frontiers in Earth Science | Espinoza, J.; Garreaud, R.; Poveda, G.; Arias, P.; Molina-Carpio, J.; Masiokas, M.; Viale, M.; Scaff, L. | 2020 | Agua y Extremos | 10.3389/feart.2020.00064 | https://www.frontiersin.org/article/10.3389/feart.2020.00064/full | 64 | Vol: 8 | 2296-6463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Andes is the longest cordillera in the world and extends from northern South America to the southern extreme of the continent (from 11°N to 53°S). The Andes runs through seven countries and is characterized by a wide variety of ecosystems strongly related to the contrasting climate over its eastern and western sides, as well as along its latitudinal extension. This region faces very high potential impacts of climate change, which could affect food and water security for about 90 million people. In addition, climate change represents an important threat on biodiversity, particularly in the tropical Andes, which is the most biodiverse region on Earth. From a scientific and societal view, the Andes exhibits specific challenges because of its unique landscape and the fragile equilibrium between the growing population and its environment. In this manuscript, we provide an updated review of the most relevant scientific literature regarding the hydroclimate of the Andes with an integrated view of the entire Andes range. This review paper is presented in two parts. Part I is dedicated to summarize the scientific knowledge about the main climatic features of the Andes, with emphasis on mean large-scale atmospheric circulation, the Andes-Amazon hydroclimate interconnections and the most distinctive diurnal and annual cycles of precipitation. Part II, which is also included in the research topic “Connecting Mountain Hydroclimate Through the American Cordilleras,” focuses on the hydroclimate variability of the Andes at the sub-continental scale, including the effects of El Niño-Southern Oscillation. © Copyright © 2020 Espinoza, Garreaud, Poveda, Arias, Molina-Carpio, Masiokas, Viale and Scaff. |
| Nitrous oxide distribution in the continental shelf off Central Chile (2005-2009) | Farías, L.; Faúndez, J. | 2020 | Zonas Costeras | 10.1594/PANGAEA.916020 | https://doi.pangaea.de/10.1594/PANGAEA.916020 | Pangaea | English | Continental shelves tend to have high standing stocks of organic carbon and high rates of primary production relative to the open ocean and serve as important link between land and the ocean interior and between the sediment and the water column, playing a key role in the N and C balance, and accounting for up to 50% of the total N loss. One of the widest continental shelves in the eastern South Pacific (ESP) is present off central Chile (36°S). This is an important geographic feature in terms of physical and biological interactions owing to the large area available for coupling between the benthic and pelagic systems. In addition, this area is subjected to a strong coastal upwelling during austral spring and summer; when winds shift to a predominantly northward direction, stressing the sea surface layer and producing an intense cross-shelf transport and uplift of Equatorial Subsurface waters (ESSW) over the shelf. The ESSW, characterized by high NO3- and low O2 content, promotes surface fertilization and, subsequently, intense organic matter respiration and remineralization at depth, along with an efflux of subsurface-accumulated N2O (Farías et al. 2009, Cornejo & Farías, 2012). Thus, periods of maximum productivity and intense suboxia, or even anoxia, when diverse electron donors (e.g., organic matter, NH4+, NO2-, H2S) are present, represent a potential hotspot for fixed N removal processes.We present a data set that has been obtained during different FIP cruises (Fondo de Investigaciones Pesqueras) (2005-2009) which consisted of several transects perpendicular to the coast between 35° and 40°S and from the coast to 77.8° W (central Chile). Data collected include classical oceanographic variables including N2O and important greenhouse gas. | |||||
| Vertical profiles of nitrous oxide, methane and nutrients in coastal water of eastern South Pacific | Farías, L.; Faúndez, J. | 2020 | Zonas Costeras | 10.1594/PANGAEA.922967 | https://doi.pangaea.de/10.1594/PANGAEA.922967 | Pangaea | English | Between February 8th and March 4th 2007 an oceanographic cruise (Galathea 3 expedition) on board of Research Vessel Vædderen (Denmark) was performed Legs 13 and 14 of that expedition were devoted to the study of the oxygen minimum zone off northern Chile and Peru The cruise track covered the area between Valparaiso-Chile (32°S) and northern Peru (7.5°S) from total amount of 18 stations visited, we present 21 station with relatively high vertical resolution of Nitrous oxide and other variables. The main objective of the cruise was to study of low oxygen conditions over microbial communities and metabolic pathways related to the N and C cycles. In this region, an emblematic Oxygen Minimum Zone (OMZ), mainly defined by the presence of Subsurface Equatorial Waters (ESSW) between 50 and 400 m depth. These waters determine an important role of the eastern South Pacific in global climate related to the production of green house gases such as CO2, CH4 and N2O. During the cruise researcher was focused on several mechanisms of N and C transformation in the OMZ such as Fixation of molecular nitrogen (N2) and nitrous oxide (N2O) in surface waters and the core of the oxygen minimum zone and production and consumption of N2O by denitrificion and even nitrification.Continuously sampled variables:Temperature, salinity and disolved oxygen were obtained unsing a CTD-O probe (SeaBird)Discretely sampled variables:Water samples were collected using Niskin bottles attached to rosette sampler, in order to obtain discrete measurementsof dissolver oxygen (O2) and nutrients (NO3, NO2, SiO4 and PO43). Discrete samples of DO (in triplicate) were analyzed using the AULOX measurement system, an automatic Winkler method. Samples for NO2, NO3 and PO4 (15 mL in triplicate) were filtered (using a 0.45 μm GF/F glass filter) and stored (frozen) until analysis, using standard colorimetric techniques (Grasshoff, 1983). Measurements of NH4 (40 mL, in triplicate) were carried out using the fluorometric method proposed by Holmes et al. (1999). N2O and CH4 samples were taken in triplicate in 20 mL vials and carefully sealed to avoid air bubbles. They were then preserved with 50 μL of saturated HgCl2 and stored in darkness until analysis. N2O and CH4 was analyzed by creating a 5 mL headspace of ultrapure Helium and then equilibrated to 40◦C. Mesurements were carried out through gas chromatography using an electron capture detector (Varian 3380) and Flame Ionization detector (Shimadzu 17A), respectively. The calibration curves used 0.1, 0.5, and 1 ppm of N2O standards and 1, 2.5, 5 and 10 ppm of CH4 standards, both curves used pure He as 0 value. The analytical error for N2O measurements was ~3% and ~5% for CH4. CH4 was manually analyzed through a capillary column GS-Q (J&W, 0.53 mm×30 m) and 30°C oven temperature The uncertainty of the measurements was calculated from the standard deviation of the triplicate measurements by depth. Samples with a variation coefficient above 10% were not considered. | |||||
| Temporal dynamics of dissolved inorganic nitrogen (DIN) in the aphotic layer of a coastal upwelling system with variable dissolved oxygen | Journal of Marine Systems | Farías, L.; Faúndez, J.; Sanhueza-Guevara, S. | 2020 | Zonas Costeras | 10.1016/j.jmarsys.2018.06.001 | https://linkinghub.elsevier.com/retrieve/pii/S0924796317302075 | 103087 | Vol: 209 | 0924-7963 | Thomson Reuters ISI (SCIE) | English | Dissolved O2 (DO) concentration is critical to determining ecosystem functions such as organic matter respiration, which can favor fixed nitrogen loss and the accumulation of compounds such as NH4+. This dynamic is observed in central Chile's coastal upwelling system (36 °S), which presents seasonally O2 deficient waters and high biological productivity. Temporal dynamics for dissolved inorganic nitrogen (DIN: NO3−, NO2− and NH4+) are analyzed based on a ten year time series of monthly measurements of DO and DIN and a three year record of absolute DIN uptake rates (ρDIN), respective turnover rates (νDIN), and O2 utilization rates (OUR). Observed O2 deficit gradually increases from hypoxia to near anoxia as the system becomes more productive, favoring the accumulation of NO2− and NH4+. Three temporal phases within the aphotic layer were distinguished: (I) DO > 62 μmol L−1 (May to August), (II) 5 < DO < 62 μmol L−1 (September to December) and (III) DO < 5 μmol L−1 (January to April). From phase I to III, DO and NO3− inventories decreased by eight and two times, respectively, while NH4+ and NO2 inventories increased two- and five-fold, respectively. Uptake rates for NH4+ varied from 0.23 to 450 nmol N L−1 d−1 and from 1.42 to 184 nmol N L−1 d−1 for NO3−. Notably, integrated ρNH4+ increased during phase III, generating a NH4+ turnover time of 12–29 days; whereas integrated ρNO3− peaked during phase II, and removed the NO3− pool over an extended turnover time (>820 days). Integrated OUR gradually increased from phase I to III (from 225 to 422 mmol m−2 d−1), with DO pools replenished over 2.3 to 26 days. NH4+ regeneration rates ranged from 34 to 62 mmol m−2 d−1 and NH4+ pools were replenished within a few days. Variation in DO, which regulates N cycling, may explain the accumulation of N-species within the aphotic layer. Observed trends could be extrapolated to scenarios of upwelling-favorable winds, eutrophication and hypoxia. | |
| Transforming knowledge systems for life on Earth: Visions of future systems and how to get there | Energy Research & Social Science | Fazey, I.; Schäpke, N.; Caniglia, G.; Hodgson, A.; Kendrick, I.; Lyon, C.; Page, G.; Patterson, J.; Riedy, C.; Strasser, T.; Verveen, S.; Adams, D.; Goldstein, B.; Klaes, M.; Leicester, G.; Linyard, A.; McCurdy, A.; Ryan, P.; Sharpe, B.; Silvestri, G.; Abdurrahim, A.; Abson, D.; Adetunji, O.; Aldunc... | 2020 | Agua y Extremos | 10.1016/j.erss.2020.101724 | https://linkinghub.elsevier.com/retrieve/pii/S2214629620302991 | 101724 | Vol: 70 | 22146296 | Thomson Reuters ISI (SSCI) | All Open Access; Hybrid Gold Open Access | English | Formalised knowledge systems, including universities and research institutes, are important for contemporary societies. They are, however, also arguably failing humanity when their impact is measured against the level of progress being made in stimulating the societal changes needed to address challenges like climate change. In this research we used a novel futures-oriented and participatory approach that asked what future envisioned knowledge systems might need to look like and how we might get there. Findings suggest that envisioned future systems will need to be much more collaborative, open, diverse, egalitarian, and able to work with values and systemic issues. They will also need to go beyond producing knowledge about our world to generating wisdom about how to act within it. To get to envisioned systems we will need to rapidly scale methodological innovations, connect innovators, and creatively accelerate learning about working with intractable challenges. We will also need to create new funding schemes, a global knowledge commons, and challenge deeply held assumptions. To genuinely be a creative force in supporting longevity of human and non-human life on our planet, the shift in knowledge systems will probably need to be at the scale of the enlightenment and speed of the scientific and technological revolution accompanying the second World War. This will require bold and strategic action from governments, scientists, civic society and sustained transformational intent. |
| South Pacific Subtropical High from the late Holocene to the end of the 21st century: insights from climate proxies and general circulation models | Climate of the Past | Flores-Aqueveque, V.; Rojas, M.; Aguirre, C.; Arias, P.; González, C. | 2020 | Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | 10.5194/cp-16-79-2020 | https://cp.copernicus.org/articles/16/79/2020/ | 79-99 | Vol: 16 Issue: 1 | 1814-9332 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The South Pacific Subtropical High (SPSH) is a predominant feature of the South American climate. The variability of this high-pressure center induces changes in the intensity of coastal alongshore winds and precipitation, among others, over southwestern South America. In recent decades, strengthening and expansion of the SPSH have been observed and attributed to the current global warming. These changes have led to an intensification of the southerly winds along the coast of northern to central Chile and a decrease in precipitation from central to southern Chile. Motivated by improving our understanding about the regional impacts of climate change in this part of the Southern Hemisphere, we analyzed SPSH changes during the two most extreme climate events of the last millennium, the Little Ice Age (LIA) and the Current Warm Period (CWP: 1970–2000), based on paleoclimate records and CMIP5/PMIP3 model simulations. In order to assess the level of agreement of general circulation models, we also compare them with ERA-Interim reanalysis data for the 1979–2009 period as a complementary analysis. Finally, with the aim of evaluating future SPSH behavior, we include 21st century projections under a Representative Concentration Pathway (RCP8.5) scenario in our analyses. Our results indicate that during the relative warm (cold) period, the SPSH expands (contracts). Together with this change, alongshore winds intensify (weaken) south (north) of ∼35∘ S; also, southern westerly winds become stronger (weaker) and shift southward (northward). Model results generally underestimate reanalysis data. These changes are in good agreement with paleoclimate records, which suggest that these variations could be related to tropical climate dynamics but also to extratropical phenomena. However, although models adequately represent most of the South American climate changes, they fail to represent the Intertropical Convergence Zone–Hadley cell system dynamics, emphasizing the importance of improving tropical system dynamics in simulations for a better understanding of its effects on South America. Climate model projections indicate that changes recently observed will continue during the next decades, highlighting the need to establish effective mitigation and adaptation strategies against their environmental and socioeconomic impacts. |
| Initial response of understorey vegetation and tree regeneration to a mixed‐severity fire in old‐growth Araucaria–Nothofagus forests | Applied Vegetation Science | Fuentes‐Ramirez, A.; Salas‐Eljatib, C.; González, M.; Urrutia‐Estrada, J.; Arroyo‐Vargas, P.; Santibañez, P. | 2020 | Cambio de Uso de Suelo | 10.1111/avsc.12479 | https://onlinelibrary.wiley.com/doi/abs/10.1111/avsc.12479 | 210-222 | Vol: 23 Issue: 2 | 1402-2001, 1654-109X | Thomson Reuters ISI (SCIE) | English | Questions: Fire is a key factor influencing Araucaria araucana forests, but the impact of fire severity on the understorey vegetation is not well understood. In this study we seek to answer the following questions: (a) how do initial plant diversity, composition and spatial distribution of the understorey vegetation change in response to different levels of fire severity; and (b) does the abundance of dominant tree species exhibit different patterns across a fire severity gradient shortly after fire?. Location: Old-growth Araucaria araucana–Nothofagus pumilio forests in the Andes of south-central Chile (38° S, 71° W) burned in 2015. Methods: We evaluated the post-fire plant regeneration across a fire severity gradient ranging from unburned forests to areas of high fire severity. One year after fire (in February 2016), we measured woody and herbaceous species richness, abundance, height, origin (native vs exotic species), life forms and the spatial pattern of plant recovery. Results: Plant species richness and abundance were significantly higher within the unburned forest and low fire severity areas one year after fire, compared to areas of high and moderate fire severity. Overall, nearly 50% of the species present in the unburned forest were not found in areas of high severity, including the tree Nothofagus pumilio. Rapid vegetative resprouting of pioneer species such as Chusquea culeou resulted in an aggregated spatial distribution of plants after fire. Conclusions: Plant diversity and the abundance of Araucaria araucana and Nothofagus pumilio were reduced in areas of high fire severity one year after fire. Exotic species were more abundant within areas of low severity, being likely mediated by cattle browsing. Our research makes clear the potential changes in forest composition and structure if dominant tree species are not capable of recovering after fire. We recommend the exclusion of cattle within fire-affected areas and planting Nothofagus pumilio in areas of high fire severity. © 2020 International Association for Vegetation Science | |
| Mitigación de carbono negro en la actualización de la Contribución Nacionalmente Determinada de Chile: Informe extendido y anexos. | Gallardo, L.; Basoa, K.; Tolvett, S.; Osses, M.; Huneeus, N.; Bustos, S.; Barraza, J.; Ogaz, G. | 2020 | Ciudades Resilientes | https://www.cr2.cl/carbononegro/ | 116 | En el contexto del Acuerdo de París, Chile está revisando su Contribución Nacionalmente Determinada (NDC, por sus siglas en inglés). Bajo ese marco, el Centro de Ciencia del Clima y la Resiliencia (CR2, https://www.cr2.cl/), de la Facultad de Ciencias Físicas y Matemáticas de la Universidad de Chile, está apoyando a la Oficina de Cambio Climático del Ministerio del Medio Ambiente (MMA) en el diseño, evaluación y justificación –mediante la implementación de un enfoque metodológico— de una meta de reducción cuantificada de carbono negro (BC, por sus siglas en inglés), integrable y consistente con la meta de reducción de gases de efecto invernadero (GEI). Para ejecutar este apoyo se ha suscrito un acuerdo entre las partes a través del Programa de las Naciones Unidas para el Medio Ambiente (PNUMA). El mismo está en el marco de la implementación de iniciativas de acción y planificación nacional (Supporting National Action and Planning on Short-Lived Climate Pollutants, SNAP) que promueve la Coalición de Aire Limpio y Clima (CCAC, https://www.ccacoalition.org/). Aquí se presenta un informe extendido y anexos que complementan el resumen para tomadores de decisiones. |
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| Mitigación de carbono negro en la actualización de la Contribución Nacionalmente Determinada de Chile: Resumen para tomadores de decisión | Gallardo, L.; Basoa, K.; Tolvett, S.; Osses, M.; Huneeus, N.; Bustos, S.; Barraza, J.; Ogaz, G. | 2020 | Ciudades Resilientes | https://www.cr2.cl/carbononegro/ | 32 | En el contexto del Acuerdo de París, Chile está revisando su Contribución Nacionalmente Determinada (NDC, por sus siglas en inglés). Bajo ese marco, el Centro de Ciencia del Clima y la Resiliencia (CR2, www.cr2.cl/), de la Facultad de Ciencias Físicas y Matemáticas de la Universidad de Chile, está apoyando a la Oficina de Cambio Climático del Ministerio del Medio Ambiente (MMA) en el diseño, evaluación y justificación –mediante la implementación de un enfoque metodológico— de una meta de reducción cuantificada de carbono negro (BC, por sus siglas en inglés), integrable y consistente con la meta de reducción de gases de efecto invernadero (GEI). Para ejecutar este apoyo, se ha suscrito un acuerdo entre las partes a través del Programa de las Naciones Unidas para el Medio Ambiente (PNUMA). El mismo está en el marco de la implementación de iniciativas de acción y planificación nacional (Supporting National Action and Planning on Short-Lived Climate Pollutants, SNAP) que promueve la Coalición de Aire Limpio y Clima (CCAC, www.ccacoalition.org/). Aquí se presenta un resumen para tomadores de decisión, resaltando los aspectos metodológicos y los resultados más importantes del estudio. Este resumen se complementa con un informe extendido y anexos que detallan la información y relevan la interacción entre el grupo ejecutor y el mandante. |
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| Comité Científico de Cambio Climático: Los peligros de la mala calidad de aire | Gallardo, L.; Boso, A.; Barton, J.; Huneeus, N.; Jiménez, J.; Jorquera, H.; Seguel, R.; Schueftan, A.; Urquiza, A. | 2020 | Ciudades Resilientes | https://comitecientifico.minciencia.gob.cl/wp-content/uploads/2021/06/Valdes-aire_10.pdf | |||||||||
| The Central Chile Mega Drought (2010–2018): A climate dynamics perspective | International Journal of Climatology | Garreaud, R.; Boisier, J.; Rondanelli, R.; Montecinos, A.; Sepúlveda, H.; Veloso‐Aguila, D. | 2020 | Agua y Extremos; Zonas Costeras | 10.1002/joc.6219 | https://onlinelibrary.wiley.com/doi/abs/10.1002/joc.6219 | 421-439 | Vol: 40 Issue: 1 | 0899-8418 | Thomson Reuters ISI (SCIE) | English | Central Chile, home to more than 10 million inhabitants, has experienced an uninterrupted sequence of dry years since 2010 with mean rainfall deficits of 20–40%. The so‐called Mega Drought (MD) is the longest event on record and with few analogues in the last millennia. It encompasses a broad area, with detrimental effects on water availability, vegetation and forest fires that have scaled into social and economical impacts. Observations and reanalysis data reveal that the exceptional length of the MD results from the prevalence of a circulation dipole‐hindering the passage of extratropical storms over central Chile—characterized by deep tropospheric anticyclonic anomalies over the subtropical Pacific and cyclonic anomalies over the Amundsen–Bellingshausen Sea. El Niño Southern Oscillation (ENSO) is a major modulator of such dipole, but the MD has occurred mostly under ENSO‐neutral conditions, except for the winters of 2010 (La Niña) and 2015 (strong El Niño). Climate model simulations driven both with historical forcing (natural and anthropogenic) and observed global SST replicate the south Pacific dipole and capture part of the rainfall anomalies. Idealized numerical experiments suggest that most of the atmospheric anomalies emanate from the subtropical southwest Pacific, a region that has experienced a marked surface warming over the last decade. Such warming may excite atmospheric Rossby waves whose propagation intensifies the circulation pattern leading to dry conditions in central Chile. On the other hand, anthropogenic forcing (greenhouse gases concentration increase and stratospheric ozone depletion) and the associated positive trend of the Southern Annular Mode also contribute to the strength of the south Pacific dipole and hence to the intensity and longevity of the MD. Given the concomitance of the seemingly natural (ocean sourced) and anthropogenic forcing, we anticipate only a partial recovery of central Chile precipitation in the decades to come. | |
| Fire history in Andean Araucaria–Nothofagus forests: coupled influences of past human land-use and climate on fire regimes in north-west Patagonia | International Journal of Wildland Fire | González, M.; Muñoz, A.; González-Reyes, A.; Christie, D.; Sibold, J. | 2020 | Agua y Extremos; Cambio de Uso de Suelo | 10.1071/WF19174 | http://www.publish.csiro.au/?paper=WF19174 | 649 | Vol: 29 Issue: 8 | 1049-8001 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Historical fire regimes are critical for understanding the potential effects of changing climate and human land-use on forest landscapes. Fire is a major disturbance process affecting the Andean Araucaria forest landscape in north-west Patagonia. The main goals of this study were to reconstruct the fire history of the Andean Araucaria–Nothofagus forests and to evaluate the coupled influences of climate and humans on fire regimes. Reconstructions of past fires indicated that the Araucaria forest landscape has been shaped by widespread, stand-replacing fires favoured by regional interannual climate variability related to major tropical and extratropical climate drivers in the southern hemisphere. Summer precipitation and streamflow reconstructions tended to be below average during fire years. Fire events were significantly related to positive phases of the Southern Annular Mode and to warm and dry summers following El Niño events. Although Euro-Chilean settlement (1883–1960) resulted in widespread burning, cattle ranching by Pehuenche Native Americans during the 18th and 19th centuries also appears to have changed the fire regime. In the context of climate change, two recent widespread wildfires (2002 and 2015) affecting Araucaria forests appear to be novel and an early indication of a climate change driven shift in fire regimes in north-west Patagonia. |
| Informe a las naciones: Incendios en Chile: causas, impactos y resiliencia. | González, M.; Sapiains A., R.; Gómez-González, S.; Garreaud, R.; Miranda, A.; Galleguillos, M.; Jacques-Coper, M.; Pauchard, A.; Hoyos-Santillan, J.; Cordero, L.; Vasquez-Lavin, F.; Lara, A.; Aldunce, P.; Delgado, V.; Arriagada, R.; Ugarte, A.; Sepulveda-Jauregui, A.; Farías, L.; Garcia, R.; Rondane... | 2020 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2020/01/Informe-CR2-IncendiosforestalesenChile.pdf | 84 | Spanish | Los resultados presentados en este informe son parte del trabajo interdisciplinario que realiza el Centro de Ciencia del Clima y la Resiliencia (CR)2. El (CR)2 es un centro de excelencia financiado por el programa FONDAP de CONICYT (Proyecto 15110009) en el cual participan cerca de 60 científicos asociados a la Universidad de Chile, la Universidad de Concepción y la Universidad Austral de Chile. La versión electrónica de este documento está disponible en el sitio web www.cr2.cl/incendios |
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| Metagenomic Insights into the Sewage RNA Virosphere of a Large City | Viruses | Guajardo-Leiva, S.; Chnaiderman, J.; Gaggero, A.; Díez, B. | 2020 | Zonas Costeras | 10.3390/v12091050 | https://www.mdpi.com/1999-4915/12/9/1050 | 1050 | Vol: 12 Issue: 9 | 1999-4915 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Sewage-associated viruses can cause several human and animal diseases, such as gastroenteritis, hepatitis, and respiratory infections. Therefore, their detection in wastewater can reflect current infections within the source population. To date, no viral study has been performed using the sewage of any large South American city. In this study, we used viral metagenomics to obtain a single sample snapshot of the RNA virosphere in the wastewater from Santiago de Chile, the seventh largest city in the Americas. Despite the overrepresentation of dsRNA viruses, our results show that Santiago’s sewage RNA virosphere was composed mostly of unknown sequences (88%), while known viral sequences were dominated by viruses that infect bacteria (60%), invertebrates (37%) and humans (2.4%). Interestingly, we discovered three novel genogroups within the Picobirnaviridae family that can fill major gaps in this taxa’s evolutionary history. We also demonstrated the dominance of emerging Rotavirus genotypes, such as G8 and G6, that have displaced other classical genotypes, which is consistent with recent clinical reports. This study supports the usefulness of sewage viral metagenomics for public health surveillance. Moreover, it demonstrates the need to monitor the viral component during the wastewater treatment and recycling process, where this virome can constitute a reservoir of human pathogens. |
| Assessment of ECMWF SEAS5 seasonal forecast performance over South America | Weather and Forecasting | Gubler, S.; Sedlmeier, K.; Bhend, J.; Avalos, G.; Coelho, C.; Escajadillo, Y.; Jacques-Coper, M.; Martinez, R.; Schwierz, C.; de Skansi, M.; Spirig, C. | 2020 | Zonas Costeras | 10.1175/WAF-D-19-0106.1 | http://journals.ametsoc.org/doi/10.1175/WAF-D-19-0106.1 | 561-584 | Vol: 35 Issue: 2 | 0882-8156, 1520-0434 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | Seasonal predictions have a great socio-economic potential if they are reliable and skillful. In this study, we assess the prediction performance of SEAS5, version 5 of the seasonal prediction system of the European Centre for Medium-Range Weather Forecasts (ECMWF), over South America against homogenized station data. For temperature, we find highest prediction performances in the tropics during austral summer, where the probability that the predictions correctly discriminate different observed outcomes is 70%. In regions lying to the east of the Andes, the predictions of maximum and minimum temperature still exhibit considerable performance, while further to the south in Chile and Argentina the temperature prediction performance is low. Generally, the prediction performance of minimum temperature is slightly lower than for maximum temperature. The prediction performance of precipitation is generally lower and spatially and temporally more variable than for temperature. The highest prediction performance is observed at the coast and over the highlands of Colombia and Ecuador, over north-eastern part of Brazil, and over an isolated region to the north of Uruguay during DJF. In general, Nino3.4 has a strong influence on both air temperature and precipitation in the regions where ECMWF SEAS5 shows high performance, in some regions through teleconnections (e.g., to the north of Uruguay). However, we show that SEAS5 outperforms a simple empirical prediction based on Nino3.4 in most regions where the prediction performance of the dynamical model is high, thereby supporting the potential benefit of using a dynamical model instead of statistical relationships for predictions at the seasonal scale. |
| Thermo- and physicochemical properties of native and exotic forest species of Valparaíso, Chile, as essential information for fire risk management | International Journal of Wildland Fire | Guerrero, F.; Toledo, M.; Ripoll, N.; Espinoza, L.; Morales, R.; Muñoz, A.; Taborga, L.; Carrasco, Y. | 2020 | Agua y Extremos | 10.1071/WF19086 | http://www.publish.csiro.au/?paper=WF19086 | 675 | Vol: 29 Issue: 8 | 1049-8001 | Thomson Reuters ISI (SCIE) | English | Wildfires in the Valparaı́so region (Chile) account for one of the main threats to local biodiversity, ecosystem services and infrastructure. This study focused on producing an initial record of thermo- and physicochemical properties of local forest species. For this purpose, leaf samples of species found in the Peñuelas Lake National Reserve, namely Pinus radiata, Eucalyptus globulus, Acacia dealbata, Quillaja saponaria and Cryptocarya alba, were collected and analysed. Higher and lower heating value, flash point, density and moisture content tests were performed for each sample. Overall results showed that lower heating values measured for both native and exotic species could indicate a high energy release source in wildfires. However, differences in the flash point between species indicated that C. alba and E. globulus had a lower ignition resistance than other species tested, possibly due to a lower flash point. In contrast, Q. saponaria and A. dealbata had the highest flash point for native and exotic species respectively. Finally, all presented data and procedures were aimed at establishing a foundation for a national database of critical forest species properties to be used in wildfire simulation tools. This database will enhance forest fire management effectiveness in Chile. |
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| Afforestation falls short as a biodiversity strategy | Science | Gómez-González, S.; Ochoa-Hueso, R.; Pausas, J. | 2020 | Cambio de Uso de Suelo | 10.1126/science.abd3064 | https://www.sciencemag.org/lookup/doi/10.1126/science.abd3064 | 1439-1439 | Vol: 368 Issue: 6498 | 0036-8075, 1095-9203 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The recent EU Biodiversity Strategy for 2030 (1) recognizes the importance of biodiversity for increasing our resilience to natural disasters and pandemics and, thus, for human well-being. Although it proposes ambitious measures such as reversing pollinator decline and controlling invasive species, it also introduces the ill-advised idea of planting 3 billion trees. Massive tree plantation programs (2, 3) have been strongly criticized by the scientific community for their negative ecological and economic impacts and their limited role in climate change and CO2 mitigation (4–8). The specific number of trees proposed in the EU Strategy suggests a lack of a serious, science-based ecological assessment of actual restoration needs. Meeting such a target could threaten biodiverse treeless ecosystems (4, 6, 7, 9) and would waste an opportunity to implement ecologically sound management practices to restore fully functionally integrated mosaics of natural, seminatural, and sustainable agricultural ecosystems. Massive tree planting could also substantially change the fire regime, especially given the increasing frequency of heat waves and droughts in an area with high population density (10). The probability of large intense fires that threaten biodiversity and human assets is largely influenced by the type, amount, and continuity of biomass. Therefore, determining how many trees should be planted is less important than figuring out the most safe and effective conservation strategy. We need to move toward optimizing our landscapes. A diverse mosaic of nature-based production systems should be interspersed with protected natural areas to maximize biodiversity, resilience, and ecosystem services. Trees are not synonymous with biodiversity. Policy-makers and society need to internalize this message to make proper decisions in the context of environmental and health crises. |
| Mediterranean Heathland as a Key Habitat for Fire Adaptations: Evidence from an Experimental Approach | Forests | Gómez-González, S.; Paniw, M.; Durán, M.; Picó, S.; Martín-Rodríguez, I.; Ojeda, F. | 2020 | Cambio de Uso de Suelo | 10.3390/f11070748 | https://www.mdpi.com/1999-4907/11/7/748 | 748 | Vol: 11 Issue: 7 | 1999-4907 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Some fire ecology studies that have focused on garrigue-like vegetation suggest a weak selective pressure of fire in the Mediterranean Basin compared to other Mediterranean-type regions. However, fire-prone Mediterranean heathland from the western end of the Mediterranean Basin has been frequently ignored in the fire ecology literature despite its high proportion of pyrogenic species. Here, we explore the evolutionary ecology of seed traits in the generalist rockrose Cistus salviifolius L. (Cistaceae) aiming to ascertain the role of the Mediterranean heathland for fire adaptations in the Mediterranean Region. We performed a germination experiment to compare the relationship of seed size to (i) heat-stimulated germination, (ii) dormancy strength, and (iii) heat survival in plants from ‘high-fire’ heathland vs. ‘low-fire’ coastal shrubland. Germination after heat-shock treatment was higher in large seeds of both ‘high-fire’ and ‘low-fire’ habitats. However, dormancy was weaker in small seeds from ‘low-fire’ habitats. Finally, seed survival to heat shock was positively related to seed size. Our results support that seed size is an adaptive trait to fire in C. salviifolius, since larger seeds had stronger dormancy, higher heat-stimulated germination and were more resistant to heat shock. This seed size–fire relationship was tighter in ‘high-fire’ Mediterranean heathland than ‘low-fire’ coastal shrubland, indicating the existence of differential fire pressures and evolutionary trends at the landscape scale. These findings highlight the Mediterranean heathland as a relevant habitat for fire-driven evolution, thus contributing to better understand the role of fire in plant evolution within the Mediterranean region. |
| Observed Emergence of the Climate Change Signal: From the Familiar to the Unknown | Geophysical Research Letters | Hawkins, E.; Frame, D.; Harrington, L.; Joshi, M.; King, A.; Rojas, M.; Sutton, R. | 2020 | Gobernanza e Interfaz Ciencia y Política | 10.1029/2019GL086259 | https://onlinelibrary.wiley.com/doi/abs/10.1029/2019GL086259 | art: e2019GL086259 | Vol: 47 Issue: 6 | 0094-8276, 1944-8007 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Changes in climate are usually considered in terms of trends or differences over time. However, for many impacts requiring adaptation, it is the amplitude of the change relative to the local amplitude of climate variability which is more relevant. Here, we develop the concept of “signal‐to‐noise” in observations of local temperature, highlighting that many regions are already experiencing a climate which would be “unknown” by late 19th century standards. The emergence of observed temperature changes over both land and ocean is clearest in tropical regions, in contrast to the regions of largest change which are in the northern extratropics—broadly consistent with climate model simulations. Significant increases and decreases in rainfall have also already emerged in different regions with the United Kingdom experiencing a shift toward more extreme rainfall events, a signal which is emerging more clearly in some places than the changes in mean rainfall. |
| MMP-8, TRAP-5, and OPG Levels in GCF Diagnostic Potential to Discriminate between Healthy Patients’, Mild and Severe Periodontitis Sites | Biomolecules | Hernández, M.; Baeza, M.; Contreras, J.; Sorsa, T.; Tervahartiala, T.; Valdés, M.; Chaparro, A.; Hernández-Ríos, P. | 2020 | Ciudades Resilientes | 10.3390/biom10111500 | https://www.mdpi.com/2218-273X/10/11/1500 | 1500 | Vol: 10 Issue: 11 | 2218-273X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Biomarkers represent promising aids in periodontitis, host-mediate diseases of the tooth-supporting tissues. We assessed the diagnostic potential of matrix metalloproteinase-8 (MMP-8), tartrate-resistant acid phosphatase-5 (TRAP-5), and osteoprotegerin (OPG) to discriminate between healthy patients’, mild and severe periodontitis sites. Thirty-one otherwise healthy volunteers with and without periodontal disease were enrolled at the Faculty of Dentistry, University of Chile. Periodontal parameters were examined and gingival crevicular fluid was sampled from mild periodontitis sites (M; n = 42), severe periodontitis sites (S; n = 59), and healthy volunteer sites (H; n = 30). TRAP-5 and OPG were determined by commercial multiplex assay and MMP-8 by the immunofluorometric (IFMA) method. STATA software was used. All biomarkers showed a good discrimination performance. MMP-8 had the overall best performance in regression models and Receiver Operating Characteristic (ROC) curves, with high discrimination of healthy from periodontitis sites (area under the curve (AUC) = 0.901). OPG showed a very high diagnostic precision (AUC ≥ 0.95) to identify severe periodontitis sites (S versus H + M), while TRAP-5 identified both healthy and severe sites. As conclusions, MMP-8, TRAP-5, and OPG present a high precision potential in the identification of periodontal disease destruction, with MMP-8 as the most accurate diagnostic biomarker. |
| Two Centuries of Hydroclimatic Variability Reconstructed From Tree‐Ring Records Over the Amazonian Andes of Peru | Journal of Geophysical Research: Atmospheres | Humanes‐Fuente, V.; Ferrero, M.; Muñoz, A.; González‐Reyes, Á.; Requena‐Rojas, E.; Barichivich, J.; Inga, J.; Layme‐Huaman, E. | 2020 | Agua y Extremos | 10.1029/2020JD032565 | https://onlinelibrary.wiley.com/doi/10.1029/2020JD032565 | art: e2020JD032565 | Vol: 125 Issue: 18 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Almost half of the tributaries of the Amazon River originate in the tropical Andes and support large populations in mountain regions and downstream areas. However, it is difficult to assess hydroclimatic conditions or to evaluate future scenarios due to the scarcity of long, high‐quality instrumental records. Data from the Global Precipitation Climatology Project (GPCP) provide a complete record since 1979 and offer a good representation of rainfall over the tropical Andes. Longer records are needed to improve our understanding of rainfall variability and summer monsoon behavior at various scales. We developed the first annually resolved precipitation reconstruction for the tropical Andes in Peru, based on tree‐ring chronologies of Cedrela and Juglans species. The annual (November–October) reconstruction extends the short instrumental records back to 1817, explaining 68% of the total variance of precipitation over the 1979–2007 calibration period. The reconstruction reveals the well‐documented influence of El Niño‐Southern Oscillation (ENSO) on Amazon Rainfall at interannual scales (~19% of total variance) and significant multidecadal variability with alternating periods of about 40 years (~13% of rainfall variability) related to the Atlantic Multidecadal Oscillation (AMO). Both oscillatory modes can explain dry and humid periods observed within the reconstruction and are likely associated with the negative trends of rainfall in the short instrumental records and the increased drought recurrence in recent decades. Our results show that montane tropical tree rings can be used to reconstruct precipitation with exceptionally high fidelity, characterize the interannual to multidecadal variability, and identify remote forcings in the hydroclimate over the Andean Amazon Basin of Peru. |
| Evaluation of anthropogenic air pollutant emission inventories for South America at national and city scale | Atmospheric Environment | Huneeus, N.; Gon, H.; Castesana, P.; Menares, C.; Granier, C.; Granier, L.; Alonso, M.; de Fatima Andrade, M.; Dawidowski, L.; Gallardo, L.; Gomez, D.; Klimont, Z.; Janssens-Maenhout, G.; Osses, M.; Puliafito, S.; Rojas, N.; Ccoyllo, O.; Tolvett, S.; Ynoue, R. | 2020 | Ciudades Resilientes | 10.1016/j.atmosenv.2020.117606 | https://linkinghub.elsevier.com/retrieve/pii/S135223102030340X | 117606 | Vol: 235 | 13522310 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The changing composition of the atmosphere, driven by anthropogenic emissions, is the cause of anthropogenic climate change as well as deteriorating air quality. Emission inventories are essential to understand the contribution of various human activities, model and predict the changing atmospheric composition, and design cost-effective mitigation measures. At present, national emission inventories in South America (SA) focus on Greenhouse Gases (GHG) as part of their obligation to the United Nations Framework Convention for Climate Change (UNFCC) within the framework of their national communications. Emission inventories other than GHG in SA focus mainly on growing urban areas and megacities. Therefore, studies examining air quality at national, regional or continental scales in SA depend on (down-scaled) global emission inventories. This paper examines the emission estimates of air pollutants from various global inventories for five SA countries, namely Argentina, Brazil, Chile, Colombia and Peru. A more detailed analysis is conducted for the EDGAR and ECLIPSE emission inventories, in particular comparing local city-scale inventories of a major city in each country. Although total emissions between down-scaled global inventories and local city inventories are often comparable, large discrepancies exist between the sectoral contributions. This is critical, as the mitigation of poor air quality will depend on addressing the right sources. Potential sources of discrepancies between global and local inventories include the spatial distribution proxies, difference in emission factors used and/or the use of generic statistical country data when estimating emissions. This highlights the importance of using local information when generating national emission inventories, especially for air quality modeling and development of effective mitigation measures. This study represents the first step towards an increased understanding of the strengths and weaknesses of emissions information in SA. |
| Informe a las naciones: El aire que respiramos: pasado, presente y futuro – Contaminación atmosférica por MP2,5 en el centro y sur de Chile | Huneeus, N.; Urquiza, A.; Gayo, E.; Osses, M.; Arriagada, R.; Valdés, M.; Álamos, N.; Amigo, C.; Arrieta, D.; Basoa, K.; Billi, M.; Blanco, G.; Boisier, J.; Calvo, R.; Casielles, I.; Castro, M.; Chahúan, J.; Christie, D.; Cordero, L.; Correa, V.; Cortés, J.; Fleming, Z.; Gajardo, N.; Gallardo, L.; G... | 2020 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2020/09/Informe_Contaminacion_Espanol_2020.pdf | 102 | cr2.cl | Spanish | Los resultados presentados en este informe son parte del trabajo interdisciplinario que realiza el Centro de Ciencia del Clima y la Resiliencia (CR)2. El (CR)2 es un centro de excelencia financiado por el programa FONDAP de CONICYT (Proyecto 15110009) en el cual participan cerca de 60 científicos asociados a la Universidad de Chile, la Universidad de Concepción y la Universidad Austral de Chile. La versión electrónica de este documento está disponible en el sitio web www.cr2.cl/incendios |
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| Production of vaccines in Chile, the importance of local supply | Revista chilena de infectología | Ibarra, C.; Parada, M. | 2020 | Gobernanza e Interfaz Ciencia y Política | 10.4067/S0716-10182020000400413 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-10182020000400413&lng=en&nrm=iso&tlng=en | 413-421 | Vol: 37 Issue: 4 | 0716-1018 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | In Chile, vaccines were produced from the late 19th century to the early 21st century without interruption. The production was carried out in State institutes, from where the health service was supplied for the vaccination programs. In addition to manufacturing, packaging and distributing vaccines, the State institutes, in particular the Instituto Bacteriológico (IB), exported vaccines to Latin America and carried out research and development, standing out in this area with the Fuenzalida-Palacios vaccine for the control of human and canine rabies. The present study provides a list of vaccines produced in Chile at State institutes between the end of the 19th century and 2005, and a discussion on the visions of the State role that justified the actions regarding the production of vaccines in Chile. The developmental State of the mid-twentieth century gave way to the neoliberal State that was institutionalized with the 1980 constitution, which defines the subsidiary role of the State that has guided the discussion on local vaccine production in the last decades. |
| Daily and seasonal variation of the surface temperature lapse rate and 0°C isotherm height in the western subtropical Andes | International Journal of Climatology | Ibañez, M.; Gironás, J.; Oberli, C.; Chadwick, C.; Garreaud, R. | 2020 | Agua y Extremos | 10.1002/joc.6743 | https://onlinelibrary.wiley.com/doi/abs/10.1002/joc.6743 | joc.6743 | Vol: 41 Issue: S1 | 0899-8418, 1097-0088 | Thomson Reuters ISI (SCIE) | English | The spatial distribution of surface air temperatures is essential for understanding and modelling high-relief environments. Good estimations of the surface temperature lapse rate (STLR) and the 0°C isotherm height (H0) are fundamental for hydrological modelling in mountainous basins. Although STLR changes in space and time, it is typically assumed to be constant leading to errors in the estimation of direct-runoff volumes and flash-floods risk assessment. This paper characterizes daily and seasonal temporal variations of the in-situ STLR and H0 over the western slope of the subtropical Andes (central Chile). We use temperature data collected during 2 years every 10 min by a 16 sensors network in a small catchment with elevations ranging between 700 and 3,250 m. The catchment drains directly into Santiago, the Chilean capital with more than seven million inhabitants. Resulting values are compared against those obtained using off-site, operational data sets. Significant intra- and inter-day variations of the in-situ STLR were found, likely reflecting changes in the low-level temperature inversion during dry conditions. The annual average in-situ STLR is −5.9°C/km during wet-weather conditions. Furthermore, STLR and H0 estimations using off-site gauges are extremely sensitive to the existence of gauging stations at high elevations. | |
| Soccer games and record-breaking PM2.5 pollution events in Santiago, Chile | Atmospheric Chemistry and Physics | Lapere, R.; Menut, L.; Mailler, S.; Huneeus, N. | 2020 | Ciudades Resilientes | 10.5194/acp-20-4681-2020 | https://www.atmos-chem-phys.net/20/4681/2020/ | 4681-4694 | Vol: 20 Issue: 8 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In wintertime, high concentrations of atmospheric fine particulate matter (PM2.5) are commonly observed in the metropolitan area of Santiago, Chile. Hourly peaks can be very strong, up to 10 times above average levels, but have barely been studied so far. Based on atmospheric composition measurements and chemistry-transport modeling (WRF-CHIMERE), the chemical signature of sporadic skyrocketing wintertime PM2.5 peaks is analyzed. This signature and the timing of such extreme events trace their origin back to massive barbecue cooking by Santiago's inhabitants during international soccer games. The peaks end up evacuated outside Santiago after a few hours but trigger emergency plans for the next day. Decontamination plans in Santiago focus on decreasing emissions from traffic, industry, and residential heating. Thanks to the air quality network of Santiago, this study shows that cultural habits such as barbecue cooking also need to be taken into account. For short-term forecast and emergency management, cultural events such as soccer games seem a good proxy to prognose possible PM2.5 peak events. Not only can this result have an informative value for the Chilean authorities but also a similar methodology could be reproduced for other cases throughout the world in order to estimate the burden on air quality of cultural habits. |
| +A 5680-year tree-ring temperature record for southern South America | Quaternary Science Reviews | Lara, A.; Villalba, R.; Urrutia-Jalabert, R.; González-Reyes, A.; Aravena, J.; Luckman, B.; Cuq, E.; Rodríguez, C.; Wolodarsky-Franke, A. | 2020 | Agua y Extremos; Cambio de Uso de Suelo | 10.1016/j.quascirev.2019.106087 | https://linkinghub.elsevier.com/retrieve/pii/S0277379119306924 | 106087 | Vol: 228 | 0277-3791 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | It is widely documented that the Earth’s surface temperatures have increased in recent decades. However, temperature increment patterns are not uniform around the globe, showing different or even contrasting trends. Here we present a mean maximum summer temperature record, based on tree-ring widths, over the past 5682 years (3672BC – 2009AD) for southern South America (SSA), covering from mid-Holocene to the present. This is the longest such record for the Southern Hemisphere (SH), and expands available annual proxy climate records for this region in more than 2060 years. Our record explains 49% of the temperature variation, and documents two major warm periods between 3140–2800BC and 70BC – 150AD, which coincide with the lack of evidence of glacier advances in SSA. Recent decades in the reconstruction (1959–2009) show a warming trend that is not exceptional in the context of the last five millennia. The long-term relationship between our temperature reconstruction and a reconstructed total solar irradiance record, with coinciding cycles at 293, 372, 432–434, 512 and 746 years, indicate a persistent influence of solar forcing on centennial climate variability in SSA. At interannual to interdecadal scales, reconstructed temperature is mainly related to the internal climate variability of the Pacific Ocean, including El Niño Southern Oscillation (ENSO) and longer oscillations. Our study reveals the need to characterize regional-scale climate variability and its drivers, which in the context of global-scale processes such as anthropogenic warming, interact to modulate local climate affecting humans and ecosystems. |
| Ecology of the collapse of Rapa Nui society | Proceedings of the Royal Society B: Biological Sciences | Lima, M.; Gayo, E.; Latorre, C.; Santoro, C.; Estay, S.; Cañellas-Boltà, N.; Margalef, O.; Giralt, S.; Sáez, A.; Pla-Rabes, S.; Chr. Stenseth, N. | 2020 | Ciudades Resilientes | 10.1098/rspb.2020.0662 | https://royalsocietypublishing.org/doi/10.1098/rspb.2020.0662 | 20200662 | Vol: 287 Issue: 1929 | 0962-8452, 1471-2954 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Collapses of food producer societies are recurrent events in prehistory and have triggered a growing concern for identifying the underlying causes of convergences/divergences across cultures around the world. One of the most studied and used as a paradigmatic case is the population collapse of the Rapa Nui society. Here, we test different hypotheses about it by developing explicit population dynamic models that integrate feedbacks between climatic, demographic and ecological factors that underpinned the socio-cultural trajectory of these people. We evaluate our model outputs against a reconstruction of past population size based on archaeological radiocarbon dates from the island. The resulting estimated demographic declines of the Rapa Nui people are linked to the long-term effects of climate change on the island's carrying capacity and, in turn, on the ‘per-capita food supply’. |
| Future Changes in the Free Tropospheric Freezing Level and Rain–Snow Limit: The Case of Central Chile | Atmosphere | Mardones, P.; Garreaud, R. | 2020 | Agua y Extremos | 10.3390/atmos11111259 | https://www.mdpi.com/2073-4433/11/11/1259 | 1259 | Vol: 11 Issue: 11 | 2073-4433 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The freezing level in the free troposphere often intercepts the terrain of the world’s major mountain ranges, creating a rain–snow limit. In this work, we use the free tropospheric height of the 0 °C isotherm (H0) as a proxy of both levels and study its distribution along the western slope of the subtropical Andes (30°–38° S) in present climate and during the rest of the 21st century. This portion of the Andes corresponds to central Chile, a highly populated region where warm winter storms have produced devastating landslides and widespread flooding in the recent past. Our analysis is based on the frequency distribution of H0 derived from radiosonde and surface observations, atmospheric reanalysis and climate simulations. The future projections primarily employ a scenario of heavy greenhouse gasses emissions (RCP8.5), but we also examine the more benign RCP4.5 scenario. The current H0 distribution along the central Chile coast shows a gradual decrease southward, with mean heights close to 2600 m ASL (above sea level) at 30 °C S to 2000 m ASL at 38° S for days with precipitation, about 800 m lower than during dry days. The mean value under wet conditions toward the end of the century (under RCP8.5) is close to, or higher than, the upper quartile of the H0 distribution in the current climate. More worrisome, H0 values that currently occur only 5% of the time will be exceeded in about a quarter of the rainy days by the end of the century. Under RCP8.5, even moderate daily precipitation can increase river flow to levels that are considered hazardous for central Chile. |
| A Twitter-Lived Red Tide Crisis on Chiloé Island, Chile: What Can Be Obtained for Social-Ecological Research through Social Media Analysis? | Sustainability | Mascareño, A.; Henríquez, P.; Billi, M.; Ruz, G. | 2020 | Gobernanza e Interfaz Ciencia y Política | 10.3390/su12208506 | https://www.mdpi.com/2071-1050/12/20/8506 | 8506 | Vol: 12 Issue: 20 | 2071-1050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Considering traditional research on social-ecological crises, new social media analysis, particularly Twitter data, contributes with supplementary exploration techniques. In this article, we argue that a social media approach to social-ecological crises can offer an actor-centered meaningful perspective on social facts, a depiction of the general dynamics of meaning making that takes place among actors, and a systemic view of actors’ communication before, during and after the crisis. On the basis of a multi-technique approach to Twitter data (TF-IDF, hierarchical clustering, egocentric networks and principal component analysis) applied to a red tide crisis on Chiloé Island, Chile, in 2016, the most significant red tide in South America ever, we offer a view on the boundaries and dynamics of meaning making in a social-ecological crisis. We conclude that this dynamics shows a permanent reflexive work on elucidating the causes and effects of the crisis that develops according to actors’ commitments, the sequence of events, and political conveniences. In this vein, social media analysis does not replace good qualitative research, it rather opens up supplementary possibilities for capturing meanings from the past that cannot be retrieved otherwise. This is particularly relevant for studying social-ecological crises and supporting collective learning processes that point towards increased resilience capacities and more sustainable trajectories in affected communities. |
| Predicting spatial variability of selected soil properties using digital soil mapping in a rainfed vineyard of central Chile | Geoderma Regional | Mashalaba, L.; Galleguillos, M.; Seguel, O.; Poblete-Olivares, J. | 2020 | Cambio de Uso de Suelo | 10.1016/j.geodrs.2020.e00289 | https://linkinghub.elsevier.com/retrieve/pii/S2352009420300389 | e00289 | Vol: 22 | 23520094 | Thomson Reuters ISI (SCIE) | English | Soil physical properties influence vineyard behavior, therefore the knowledge of their spatial variability is essential for making vineyard management decisions. This study aimed to model and map selected soil properties by means of knowledge-based digital soil mapping approach. We used a Random Forest (RF) algorithm to link environmental covariates derived from a LiDAR flight and satellite spectral information, describing soil forming factors and ten selected soil properties (particle size distribution, bulk density, dispersion ratio, Ksat, field capacity, permanent wilting point, fast drainage pores and slow drainage pores) at three depth intervals, namely 0–20, 20–40, and 40–60 cm at a systematic grid (60 × 60 m2). The descriptive statistics showed low to very high variability within the field. RF model of particle size distribution, and bulk density performed well, although the models could not reliably predict saturated hydraulic conductivity. There was a better prediction performance (based on 34% model validation) in the upper depth intervals than the lower depth intervals (e.g., R2 of 0.66; nRMSE of 27.5% for clay content at 0–20 cm and R2 of 0.51; nRMSE of 16% at 40–60 cm). There was a better prediction performance in the lower depth intervals than the upper depth intervals (e.g., R2 of 0.49; nRMSE of 23% for dispersion ratio at 0–20 cm and R2 of 0.81; nRMSE of 30% at 40–60 cm). RF model overestimated areas with low values and underestimated areas with high values. Further analysis suggested that Topographic position Index, Topographic Wetness Index, aspect, slope length factor, modified catchment area, catchment slope, and longitudinal curvature were the dominant environmental covariates influencing prediction of soil properties. | |
| Increasing trends (2001–2018) in photochemical activity and secondary aerosols in Santiago, Chile | Tellus B: Chemical and Physical Meteorology | Menares, C.; Gallardo, L.; Kanakidou, M.; Seguel, R.; Huneeus, N. | 2020 | Ciudades Resilientes | 10.1080/16000889.2020.1821512 | https://www.tandfonline.com/doi/full/10.1080/16000889.2020.1821512 | 1-18 | Vol: 72 Issue: 1 | 1600-0889 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Despite the decline in partially (PM10) and fully (PM2.5) inhalable particles observed in recent decades, Santiago in Chile shows high levels of particle and ozone pollution. Attainment plans have emphasized measures aimed at curbing primary and, to some extent, secondary particles, but little attention has been paid to photochemical pollution. Nevertheless, ozone hourly mixing ratios in Eastern Santiago regularly exceed 110 ppbv in summer, and in winter maximum mixing ratios often reach 90 ppbv. Moreover, the sum of ozone and nitrogen dioxide shows an increasing trend of more than 3.5 ppbv per decade at 5 out of 8 stations. This trend is driven by increasing NO2, possibly associated with increasing motorization but also with changes in photochemistry. To estimate the fraction of secondary particles in PM2.5 and due to the lack of long-term speciation data for particles, we use carbon monoxide as a proxy of primary particles and ozone daily maxima as a proxy for secondary particle formation. We find a growing fraction of secondary particles due to an increase in the oxidizing capacity of Santiago’s atmosphere. This stresses the need for new curbing measures to tackle photochemical pollution. This is particularly needed in the context of a changing climate. |
| Informe Proyecto ARClim: Bosques Nativos y Plantaciones Forestales. | Miranda, A.; Carrasco, J.; Gonzalez, M.; Mentler, R.; Moletto, I.; Altamirano, A.; Lara, A. | 2020 | Cambio de Uso de Suelo | ||||||||||
| Evidence-based mapping of the wildland-urban interface to better identify human communities threatened by wildfires | Environmental Research Letters | Miranda, A.; Carrasco, J.; González, M.; Pais, C.; Lara, A.; Altamirano, A.; Weintraub, A.; Syphard, A. | 2020 | Cambio de Uso de Suelo | 10.1088/1748-9326/ab9be5 | https://iopscience.iop.org/article/10.1088/1748-9326/ab9be5 | 094069 | Vol: 15 Issue: 9 | 1748-9326 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The wildland-urban interface (WUI) is the spatial manifestation of human communities coupled with vegetated ecosystems. Spatial delineation of the WUI is important for wildfire policy and management, but is typically defined according to spatial relationships between housing development and wildland vegetation without explicit consideration of fire risk. A fire risk-based definition of WUI can enable a better distribution of management investment so as to maximize social return. We present a novel methodological approach to delineate the WUI based on a fire risk assessment. The approach establishes a geographical framework to model fire risk via machine learning and generate multi-scale, variable-specific spatial thresholds for translating fire probabilities into mapped output. To determine whether fire-based WUI mapping better captures the spatial congruence of houses and wildfires than conventional methods, we compared national and subnational fire-based WUI maps for Chile to WUI maps generated only with housing and vegetation thresholds. The two mapping approaches exhibited broadly similar spatial patterns, the WUI definitions covering almost the same area and containing similar proportions of the housing units in the area under study (17.1% vs. 17.9%), but the fire-based WUI accounted for 13.8% more spatial congruence of fires and people (47.1% vs. 33.2% of ignitions). Substantial regional variability was found in fire risk drivers and the corresponding spatial mapping thresholds, suggesting there are benefits to developing different WUI maps for different scales of application. We conclude that a dynamic, multi-scale, fire-based WUI mapping approach should provide more targeted and effective support for decision making than conventional approaches. |
| Forest browning trends in response to drought in a highly threatened mediterranean landscape of South America | Ecological Indicators | Miranda, A.; Lara, A.; Altamirano, A.; Di Bella, C.; González, M.; Julio Camarero, J. | 2020 | Cambio de Uso de Suelo | 10.1016/j.ecolind.2020.106401 | https://linkinghub.elsevier.com/retrieve/pii/S1470160X20303381 | 106401 | Vol: 115 | 1470160X | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Deforestation is widely studied throughout the world. However, a less evident issue is the effect of climate change and drought on remnants of native forests. The objective of this work was to understand the geographic variations in resistance to drought of the Mediterranean sclerophyllous forests of central Chile. These forests have been historically reduced and fragmented and in recent years were subjected to the most prolonged drought occurred between 2010 and 2017. Using data from the MODIS satellite sensor, temporal trends in the NDVI (Normalized Difference Vegetation Index) were quantified. We related these trends with different environmental variables to understand the effects of geographical variation and forest type as indicators of resistance to drought. We observed a significant direct effect of drought, attributable to the reduced precipitation in central Chile, and a significantly reduced NDVI in near one-third of the region forests (browning). However, NDVI and therefore forest productivity were more stable in some mesic sites such as ravine bottoms, but not on south-facing slopes. This suggests that under a regime of reduced precipitations, a greater available soil humidity would be a more important factor than the fact of receiving less solar radiation. Finally, the highest degree of browning was observed in semi-arid sclerophyllous forest dominated by species tolerant to drought. Our findings emphasize the need to consider topographic site conditions to adequately assess forest productivity and vulnerability where local wet conditions could provide drought refuges. This recent drought may be analogous to forecasted warmer and drier climate conditions with more frequent and severe droughts, so our results may serve as a general framework for climate-smart decisions in highly threatened forest restoration and conservation. |
| Enhanced Chlorinated very Short-Lived Substances in South East Asia: Potential Source Regions and Source Types | IOP Conference Series: Earth and Environmental Science | Mohd Hanif, N.; Reeves, C.; Oram, D.; Ashfold, M.; Panagi, M.; Fleming, Z.; Gooch, L.; Laube, J.; Abu Samah, A.; Amin Abdullah, A.; Sturges, W. | 2020 | Ciudades Resilientes | 10.1088/1755-1315/616/1/012011 | https://iopscience.iop.org/article/10.1088/1755-1315/616/1/012011 | 012011 | Vol: 616 | 1755-1315 | Not indexed | All Open Access; Gold Open Access; Green Open Access | English | Enhancements of the mixing ratios of short-lived halogenated gases were observed in air samples collected at Bachok Marine Research Station (BMRS), Peninsular Malaysia during Northern Hemisphere winters in 2013/2014 and 2015/2016. This study investigates the potential source regions and source types that influenced the variability in chlorinated very short-lived substances (Cl-VSLS) [dichloromethane, 1,2-dichloroethane, trichloromethane, tetrachloroethene] and methyl halides [methyl chloride and methyl bromide]. The UK Met Office's Numerical Atmospheric Modelling Environment (NAME) dispersion model, was used for tracking the origin of air masses arriving at BMRS. For the purpose of identifying possible sources of these compounds, carbon monoxide (CO) emission data taken from the Representative Concentration Pathway 8.5 were used along with NAME footprints to calculate modelled CO mixing ratios. A correlation analysis between the mixing ratios of measured compounds and the modelled CO from various emission sectors was perform to assess the extent to which emission sectors might be related to the mixing ratios of halogenated gases. The results show that the events of higher mixing ratios were associated with air masses, especially from East China. During the 2013/2014 campaign, the modelled CO from industrial, solvents and agriculture (waste burning on fields) were significantly correlated with the mixing ratios of Cl-VSLS (R > 0.7) and methyl halides (R > 0.40). During the 2015/2016 campaign, the strength of these correlations reduced for Cl-VSLS (R > 0.5) and with no significant correlations for methyl halides. Instead, mixing ratios of methyl halides were correlated (R=0.4) with modelled CO from forest burning. This work provides evidence that East and South East Asia act as important sources of halogenated gases. This is of significant given the proximity of these regions to prevalent deep convection which can rapidly transport these halogencontaining gases into the stratosphere and impact the ozone layer. |
| Sentencia del Tribunal Constitucional: Ley de Presupuesto y Sistema de Evaluación Ambiental “Requerimiento de Inconstitucionalidad presentado por un Grupo de H. Diputados que representan más de la Cuarta Parte de los Miembros en Ejercicio Respecto de las Modificaciones introducidas por el Senado al Capítulo 06, Programa 01, Subtítulo 33, Ítem 02, Asignación 005, Partida 13 del Ministerio de Agricultura, que incorpora una nueva glosa al proyecto de ley de Presupuestos del Sector Público para el año 2020, cor | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-chile-evaluacion-de-impacto-ambiental/ | 1989-5666 | ESCI | Sentencia del Tribunal Constitucional: Ley de Presupuesto y Sistema de Evaluación Ambiental “Requerimiento de Inconstitucionalidad presentado por un Grupo de H. Diputados que representan más de la Cuarta Parte de los Miembros en Ejercicio Respecto de las Modificaciones introducidas por el Senado al Capítulo 06, Programa 01, Subtítulo 33, Ítem 02, Asignación 005, Partida 13 del Ministerio de Agricultura, que incorpora una nueva glosa al proyecto de ley de Presupuestos del Sector Público para el año 2020, correspondiente al boletín N° 12.953-05” (Rol N° 7896-2019- CPT de fecha 26 de diciembre de 2019) | |||||
| Sentencia del Tribunal Constitucional de Chile de 14 de mayo de 2019 sobre Acceso a la Información Pública | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-chile-ley-de-transparencia/ | 1989-5666 | ESCI | ||||||
| Sentencia Corte Suprema “Farías Piña, Belisario Antonio en contra de la Directora Regional del Servicio de Evaluación Ambiental (Res. Ex. N° 584/2016)” (Rol N° 23.085-2018 de fecha 9 de marzo de 2020) | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-chile-invalidacion-justicia-ambiental/ | 1989-5666 | ESCI | ||||||
| Comentario Sentencia 3° Tribunal Ambiental de Valdivia “Gervana del Carmen Velásquez Moraga y Otros con Superintendencia del Medio Ambiente” | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-chile-evaluacion-de-impacto-ambiental-2/ | 1989-5666 | ESCI | ||||||
| Sentencia Corte de Apelaciones de Antofagasta Rol N°3106-2019 y Corte Suprema “Sandón/Guajardo” Rol N°36416 – 2019, Consulta de Pertinencia y Consulta Indígena | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-chile-evaluacion-de-impacto-ambiental-mineria/ | 1989-5666 | ESCI | ||||||
| Sentencia de la Corte Suprema Rol N°36.413-2019 “Compañía Minera Nueva Unión SpA, Servicio de Evaluación Ambiental, la Junta de Vigilancia del Río Huasco y del Director General de Aguas de Atacama” | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-chile-mineria-salud-recurso-de-proteccion/ | 1989-5666 | ESCI | ||||||
| Comentario Dictamen N°E39766N20 de la Contraloría General de la República | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-chile-ares-bajo-proteccion-oficial-permisos-de-edificacion/ | 1989-5666 | ESCI | ||||||
| Sentencia del Primer Tribunal Ambiental “Jenny Patricia Montaño Olivares y otro con Servicio de Evaluación Ambiental” (Rol: R-23-2019 de fecha 25 de noviembre de 2019) | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-principio-de-precaucion/ | 1989-5666 | ESCI | ||||||
| LE DOMMAGE ÉCOLOGIQUE FACE AU JUGE ENVIRONNEMENTAL AU CHILI | Revue juridique de l’environnement | Moraga, P. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.cairn.info/revue-revue-juridique-de-l-environnement-2020-3-page-455.html | 455 - 464 | Vol: 45 | French | Environmental courts were created in Chile in 2012, by law 20.600. This reform contributed to the development of the environmental liability elements, through a wide jurisprudential interpretation. This concerns the new understanding of the standing, the application of the presumption of responsibility and ambiguous concepts, such as "the significant damage". The environmental jurisprudence analysis shows that the specialized justice can contribute to improve the access to justice and the environmental standards effectiveness. | ||||
| Informe Final Identificación de Reformas Legales para alcanzar la meta de carbono neutralidad en Chile al 2050 | Moraga, P.; Hervé, D.; Delgado, V.; Morales, B.; Silva, M.; Jiménez, G. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.cr2.cl/informe-identificacion-de-reformas-legales-para-alcanzar-la-meta-de-carbono-neutralidad-en-chile-al-2050/ | El Acuerdo de París (AP) establece como objetivo que el aumento de la temperatura global del planeta no sobrepase los 2°C, comprometiendo a los países firmantes a esforzarse para limitarla a 1.5°C (CMNUCC, 2015). En la misma línea, el Informe especial sobre el Calentamiento Global del 1.5° (2018) del Grupo Intergubernamental de Expertos sobre el Cambio Climático (IPCC, por sus siglas en inglés), destaca una serie de impactos que podrían evitarse limitando el calentamiento global a 1.5°C en lugar de 2°C, o más. Para no sobrepasar el umbral recomendado, es fundamental mitigar los forzantes climáticos de vida media corta (SLCF, por sus siglas en inglés), particularmente metano (CH4) y carbono negro (BC), al mismo tiempo que conseguir emisiones globales netas nulas de dióxido de carbono (CO2), o neutralidad carbónica, hacia 2050 (IPCC, 2018a). |
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| Six hundred years of South American tree rings reveal an increase in severe hydroclimatic events since mid-20th century | Proceedings of the National Academy of Sciences | Morales, M.; Cook, E.; Barichivich, J.; Christie, D.; Villalba, R.; LeQuesne, C.; Srur, A.; Ferrero, M.; González-Reyes, Á.; Couvreux, F.; Matskovsky, V.; Aravena, J.; Lara, A.; Mundo, I.; Rojas, F.; Prieto, M.; Smerdon, J.; Bianchi, L.; Masiokas, M.; Urrutia-Jalabert, R.; Rodriguez-Catón, M.; Muñoz... | 2020 | Agua y Extremos; Cambio de Uso de Suelo | 10.1073/pnas.2002411117 | http://www.pnas.org/lookup/doi/10.1073/pnas.2002411117 | 16816-16823 | Vol: 117 Issue: 29 | 0027-8424, 1091-6490 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | South American (SA) societies are highly vulnerable to droughts and pluvials, but lack of long-term climate observations severely limits our understanding of the global processes driving climatic variability in the region. The number and quality of SA climate-sensitive tree ring chronologies have significantly increased in recent decades, now providing a robust network of 286 records for characterizing hydroclimate variability since 1400 CE. We combine this network with a self-calibrated Palmer Drought Severity Index (scPDSI) dataset to derive the South American Drought Atlas (SADA) over the continent south of 12°S. The gridded annual reconstruction of austral summer scPDSI is the most spatially complete estimate of SA hydroclimate to date, and well matches past historical dry/wet events. Relating the SADA to the Australia–New Zealand Drought Atlas, sea surface temperatures and atmospheric pressure fields, we determine that the El Niño–Southern Oscillation (ENSO) and the Southern Annular Mode (SAM) are strongly associated with spatially extended droughts and pluvials over the SADA domain during the past several centuries. SADA also exhibits more extended severe droughts and extreme pluvials since the mid-20th century. Extensive droughts are consistent with the observed 20th-century trend toward positive SAM anomalies concomitant with the weakening of midlatitude Westerlies, while low-level moisture transport intensified by global warming has favored extreme rainfall across the subtropics. The SADA thus provides a long-term context for observed hydroclimatic changes and for 21st-century Intergovernmental Panel on Climate Change (IPCC) projections that suggest SA will experience more frequent/severe droughts and rainfall events as a consequence of increasing greenhouse gas emissions. |
| Sedimentation rate of settleable particulate matter in Santiago city, Chile | Environmental Quality Management | Morales‐Casa, V.; Barraza, F.; Collante, E.; Ginocchio, R.; Jorquera, H.; Lambert, F.; Ospina, E.; Sáez‐Navarrete, C.; Varas, J. | 2020 | Ciudades Resilientes | 10.1002/tqem.21672 | https://onlinelibrary.wiley.com/doi/10.1002/tqem.21672 | 17-25 | Vol: 29 Issue: 3 | 1088-1913, 1520-6483 | Thomson Reuters ISI (ESCI) | English | Settleable particulate matter (SPM) is an atmospheric pollutant harmful to human health and the environment in high concentrations. Despite this fact, no up‐to‐date information on SPM levels exists for the capital of Chile, Santiago (7 million inhabitants). To address this knowledge gap, SPM sedimentation rates, including soluble and insoluble components, were measured at three different urban sites from July to November of 2016. We compare the measurements with ambient and meteorological information, as well as urban typology settings. Our results indicate SPM deposition rates between 2.5 and 3.9 g/(m2·30 days). Only one site exceeded the national limit of 4.5 g/(m2·30 days), but we found an increasing trend in all three sites. SPM and its insoluble sedimentation rates increased during warm and dry months and presented significant correlations with meteorological parameters. The highest sedimentation rates were measured at the location with the least permeable surfaces and the lowest green spaces, while the lowest sedimentation rates were found in the sites with abundant green spaces and permeable soil. No significant differences were detected in the soluble components. Our results suggest that SPM levels in Santiago are close to the national limit and may increase with climate change and urban expansion. |
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| Wildfire management in Mediterranean-type regions: paradigm change needed | Environmental Research Letters | Moreira, F.; Ascoli, D.; Safford, H.; Adams, M.; Moreno, J.; Pereira, J.; Catry, F.; Armesto, J.; Bond, W.; Gonzalez, M.; Curt, T.; Koutsias, N.; McCaw, L.; Price, O.; Pausas, J.; Rigolot, E.; Stephens, S.; Tavsanoglu, C.; Vallejo, R.; Van Wilgen, B.; Xanthopoulos, G.; Fernandes, P. | 2020 | Cambio de Uso de Suelo | 10.1088/1748-9326/ab541e | http://iopscience.iop.org/article/10.1088/1748-9326/ab541e | 011001 | Vol: 15 Issue: 1 | 1748-9326 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | During the last decades, climate and land use changes led to an increased prevalence of megafires in Mediterranean-type climate regions (MCRs). Here, we argue that current wildfire management policies in MCRs are destined to fail. Focused on fire suppression, these policies largely ignore ongoing climate warming and landscape-scale buildup of fuels. The result is a "firefighting trap" that contributes to ongoing fuel accumulation precluding suppression under extreme fire weather, and resulting in more severe and larger fires. We believe that a "business as usual" approach to wildfire in MCRs will not solve the fire problem, and recommend that policy and expenditures be rebalanced between suppression and mitigation of the negative impacts of fire. This requires a paradigm shift: policy effectiveness should not be primarily measured as a function of area burned (as it usually is), but rather as a function of avoided socio-ecological damage and loss. |
| Timing and structure of vegetation, fire, and climate changes on the Pacific slope of northwestern Patagonia since the last glacial termination | Quaternary Science Reviews | Moreno, P. | 2020 | Agua y Extremos | 10.1016/j.quascirev.2020.106328 | https://linkinghub.elsevier.com/retrieve/pii/S0277379120302900 | 106328 | Vol: 238 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | By virtue of its location in the southern mid-latitudes, northwestern Patagonia (40°-44°S) offers the opportunity to unravel the mechanisms involved in the initiation and propagation of paleoclimate signals of hemispheric and global significance. Of particular importance is deciphering the evolution of the Southern Westerly Winds (SWW) considering their influence at continental, zonal, hemispheric, and global scale. Here I present a multi-decadal record from Lago Proschle, a small closed-basin lake located on the Pacific slope of northwestern Patagonia, to examine the timing and structure of vegetation, fire, and climate change along a continuum since the onset of the Last Glacial Termination (T1). The record shows rapid glacier recession during T1, reaching the western Andean foothills in ∼400 years or less. Nothofagus-dominated forests established between ∼17.4–17 ka, followed by closed-canopy North Patagonian Rain Forests (NPRF) with shade-tolerant thermophilous trees between ∼16.3–15.4 ka. These changes suggest an abrupt warming trend and an increase in precipitation at ∼16.3 ka, associated with a northward shift of the SWW. Subsequent increases in cold-tolerant hygrophilous trees between ∼15.4–12.8 ka imply a shift to cold, more humid conditions during the Antarctic Cold Reversal, suggesting stronger SWW influence. This was followed by stand-replacing fires brought by a sudden decline in summer precipitation at ∼12.8 ka, associated with a millennial-scale southward shift of the SWW which was contemporaneous with the onset of the Younger Dryas. Dominance of thermophilous, summer-drought tolerant Valdivian rainforest trees and high fire activity ensued between ∼10.3–7.8 ka, suggesting peak warmth and overall decline in annual precipitation associated with weakening of the SWW during the early Holocene. A multi-millennial cooling and wetting trend started at ∼7.8 ka, brought by stronger SWW influence, followed by recurrent, centennial-scale variations in temperature and precipitation starting at ∼6.4 ka. Deforestation, fire, and spread of non-native herbs by Chilean/European settlers began during the late 18th century. Abrupt vegetation changes in the Lago Proschle record were driven by rapid climate changes over the last 17,400 years amplified, in some instances, by fire disturbance. © 2020 Elsevier Ltd | |
| Water Crisis in Petorca Basin, Chile: The Combined Effects of a Mega-Drought and Water Management | Water | Muñoz A.; Klock-Barría, K.; Alvarez-Garreton, C.; Aguilera-Betti, I.; González-Reyes, Á.; Lastra, J.; Chávez, R.; Barría, P.; Christie, D.; Rojas-Badilla, M.; Quesne, C. | 2020 | Agua y Extremos | 10.3390/w12030648 | https://www.mdpi.com/2073-4441/12/3/648 | 648 | Vol: 12 Issue: 3 | 2073-4441 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Since 2010, Chile has experienced one of the most severe droughts over the last century, the so-called mega-drought (MD). The MD conditions, combined with intensive agricultural activities and the current water management system, have led to water scarcity problems in Mediterranean and Semi-arid regions of Chile. An emblematic case is the Petorca basin, where a water crisis is undergone. To characterize this crisis, we analyzed water provision by using tree-ring records, remote sensing, instrumental data, and allocated water rights within the basin. Results indicate that the MD is the most severe dry period over the last 700-years of streamflow reconstruction. During the MD, streamflow and water bodies of the upper parts of the basin have been less affected than mid and low areas of this valley, where consumptive withdrawals reach up to 18% of the mean annual precipitation. This extracted volume is similar to the MD mean annual precipitation deficits. The impacts of the current drought, along with the drier climate projections for Central Chile, emphasize the urgency for faster policy changes related to water provision. Climate change adaptation plans and policies should enhance the current monitoring network and the public control of water use to secure the water access for inhabitants and productive activities. |
| Raco Wind at the Exit of the Maipo Canyon in Central Chile: Climatology, Special Observations, and Possible Mechanisms | Journal of Applied Meteorology and Climatology | Muñoz R.; Armi, L.; Rutllant, J.; Falvey, M.; Whiteman, C.; Garreaud, R.; Arriagada, A.; Flores, F.; Donoso, N. | 2020 | Agua y Extremos | 10.1175/JAMC-D-19-0188.1 | http://journals.ametsoc.org/doi/10.1175/JAMC-D-19-0188.1 | 725-749 | Vol: 59 Issue: 4 | 1558-8424, 1558-8432 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Raco is the local name given to a strong (gusts up to 17 m s −1 ), warm, and dry down-valley wind observed at the exit of the Maipo River Canyon in central Chile. Its climatology is documented based on eight years of surface measurements near the canyon exit together with a more complete characterization of its structure during an intensive observational period (IOP) carried out in July 2018. Raco winds occur in the cold season under well-defined synoptic conditions, beginning abruptly at any time during the night, reaching maximum hourly averages around 10 m s −1 , and terminating around noon with the onset of afternoon westerly up-valley winds. About 25% of the days in May–August have more than six raco hours between 0100 and 1200 LT, and raco episodes last typically 1–2 days. The sudden appearance of raco winds at the surface can be accompanied by conspicuous warming (up to 10°C) and drying (up to 3 g kg −1 ). Raco winds are associated with a strong along-canyon pressure gradient, a regional pressure fall, and clear skies. During the IOP, radiosondes launched from both extremes of the canyon exit corridor showed a nocturnal easterly jet at 700 m AGL that occasionally descended rapidly to the surface, producing the raco. Transects along the canyon performed with a mobile ceilometer revealed a sharp frontlike feature between the cold pool over the Santiago Valley and the raco-affected conditions in the Maipo Canyon. Possible factors producing the easterly jet aloft and its occasional descent toward the surface are discussed, and a gap-wind mechanism is postulated to be at work. |
| Decarbonization Tradeoffs: A Dynamic General Equilibrium Modeling Analysis for the Chilean Power Sector | Sustainability | Nasirov, S.; O’Ryan, R.; Osorio, H. | 2020 | Gobernanza e Interfaz Ciencia y Política | 10.3390/su12198248 | https://www.mdpi.com/2071-1050/12/19/8248 | 8248 | Vol: 12 Issue: 19 | 2071-1050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Medium size developing countries like Chile that commit to decarbonization goals need to carefully assess the trade-offs associated to their intensity and timing, since most of the technologies required will be absorbed, not produced, by these countries. A rapid expansion of renewables in the Chilean energy matrix, mostly thanks to exceptional solar and wind resources, combined with a rapid decrease in the cost of renewable energy technologies, intensified current policy debates to reduce the role of coal, which is the largest source of CO2 emissions in the generation mix. Recently, the main generation companies in Chile made a voluntary commitment to not invest in new coal projects that do not include carbon capture and storage systems. In addition, the Chilean government announced its plans to phase out coal plants completely by 2040. In this context, the aim of this research is to study the economy-wide and emission reduction impacts of different decarbonization paths in the Chilean power sector. For this purpose, we consider dynamic simulations using a new energy-oriented version of the Computable General Equilibrium Model (CGE)- General Equilibrium Model for the Chilean Economy (ECOGEM)-Chile which is soft linked to the bottom-up engineering energy model. The results show the major impacts under both the business as usual (BAU) scenario and the coal phase-out scenario. Additionally, the study discusses to what extent the ambitious decarbonization goals of the Chilean government are coherent with the current technological limitations. |
| ARCLIM Anexo: Exploración de un Índice de Resiliencia Genérica en ARClim – Atlas de Riesgo Climático | Neira, C.; Rauld, J.; Alamos, N.; Billi, M.; Urquiza, A. | 2020 | Ciudades Resilientes | ||||||||||
| Comité Científico de Cambio Climático: Oportunidades para una reactivación resiliente | O Ryan, R.; Rojas, M.; Villavicencio, A. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://comitecientifico.minciencia.gob.cl/wp-content/uploads/2021/06/Oryan-reactivacion_10.pdf | |||||||||
| El cambio antropogénico del uso del suelo y el régimen de incendios forestales | Chile forestal | Ortega, M.; Gómez-González, S.; Paula, S. | 2020 | Cambio de Uso de Suelo | https://www.conaf.cl/cms/editorweb/chifo/396/files/assets/common/downloads/Revista%20Chile%20Forestal%20N.pdf?uni=089ddeb702ff71a34a438b06922c503e | 11-13 | 2452-5057 | La ecología del fuego permitirá enfrentar el desafío que presenta hoy el cambio climático, donde el incremento de las temperaturas y de la sequía favorece la frecuencia y severidad de los incendios forestales, y donde por lo mismo se hace necesario que el país rediseñe su paisaje forestal. | |||||
| The deglaciation of the Americas during the Last Glacial Termination | Earth-Science Reviews | Palacios, D.; Stokes, C.; Phillips, F.; Clague, J.; Alcalá-Reygosa, J.; Andrés, N.; Angel, I.; Blard, P.; Briner, J.; Hall, B.; Dahms, D.; Hein, A.; Jomelli, V.; Mark, B.; Martini, M.; Moreno, P.; Riedel, J.; Sagredo, E.; Stansell, N.; Vázquez-Selem, L.; Vuille, M.; Ward, D. | 2020 | Agua y Extremos | 10.1016/j.earscirev.2020.103113 | https://linkinghub.elsevier.com/retrieve/pii/S001282521930652X | 103113 | Vol: 203 | 0012-8252 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | This paper reviews current understanding of deglaciation in North, Central and South America from the Last Glacial Maximum to the beginning of the Holocene. Together with paleoclimatic and paleoceanographic data, we compare and contrast the pace of deglaciation and the response of glaciers to major climate events. During the Global Last Glacial Maximum (GLGM, 26.5-19 ka), average temperatures decreased 4° to 8°C in the Americas, but precipitation varied strongly throughout this large region. Many glaciers in North and Central America achieved their maximum extent during the GLGM, whereas others advanced even farther during the subsequent Heinrich Stadial 1 (HS-1). Glaciers in the Andes also expanded during the GLGM, but that advance was not the largest, except on Tierra del Fuego. HS-1 (17.5-14.6 ka) was a time of general glacier thickening and advance throughout most of North and Central America, and in the tropical Andes; however, glaciers in the temperate and subpolar Andes thinned and retreated during this period. During the Bølling-Allerød interstadial (B-A, 14.6-12.9 ka), glaciers retreated throughout North and Central America and, in some cases, completely disappeared. Many glaciers advanced during the Antarctic Cold Reversal (ACR, 14.6-12.9 ka) in the tropical Andes and Patagonia. There were small advances of glaciers in North America, Central America and in northern South America (Venezuela) during the Younger Dryas (12.9-11.7 ka), but glaciers in central and southern South America retreated during this period, except on the Altiplano where advances were driven by an increase in precipitation. Taken together, we suggest that there was a climate compensation effect, or ‘seesaw’, between the hemispheres, which affected not only marine currents and atmospheric circulation, but also the behavior of glaciers. This seesaw is consistent with the opposing behavior of many glaciers in the Northern and Southern Hemispheres. |
| Investigating the regional contributions to air pollution in Beijing: a dispersion modelling study using CO as a tracer | Atmospheric Chemistry and Physics | Panagi, M.; Fleming, Z.; Monks, P.; Ashfold, M.; Wild, O.; Hollaway, M.; Zhang, Q.; Squires, F.; Vande Hey, J. | 2020 | Ciudades Resilientes | 10.5194/acp-20-2825-2020 | https://www.atmos-chem-phys.net/20/2825/2020/ | 2825-2838 | Vol: 20 Issue: 5 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | The rapid urbanization and industrialization of northern China in recent decades has resulted in poor air quality in major cities like Beijing. Transport of air pollution plays a key role in determining the relative influence of local emissions and regional contributions to observed air pollution. In this paper, dispersion modelling (Numerical Atmospheric Modelling Environment, NAME model) is used with emission inventories and in situ ground measurement data to track the pathways of air masses arriving in Beijing. The percentage of time the air masses spent over specific regions during their travel to Beijing is used to assess the effects of regional meteorology on carbon monoxide (CO), a good tracer of anthropogenic emissions. The NAME model is used with the MEIC (Multi-resolution Emission Inventory for China) emission inventories to determine the amount of pollution that is transported to Beijing from the immediate surrounding areas and regions further away. This approach captures the magnitude and variability of CO over Beijing and reveals that CO is strongly driven by transport processes. This study provides a more detailed understanding of relative contributions to air pollution in Beijing under different regional airflow conditions. Approximately 45 % over a 4-year average (2013–2016) of the total CO pollution that affects Beijing is transported from other regions, and about half of this contribution comes from beyond the Hebei and Tianjin regions that immediately surround Beijing. The industrial sector is the dominant emission source from the surrounding regions and contributes over 20 % of the total CO in Beijing. Finally, using PM2.5 to determine high-pollution days, three pollution classification types of pollution were identified and used to analyse the APHH winter campaign and the 4-year period. The results can inform targeted control measures to be implemented by Beijing and the surrounding provinces to tackle air quality problems that affect Beijing and China. |
| Fabricación de vacunas en Chile una historia de producción local poco (re)conocida | Revista del Instituto de Salud Pública de Chile | Parada, M.; Ibarra, C. | 2020 | Gobernanza e Interfaz Ciencia y Política | 10.34052/rispch.v4i1.97 | https://revista.ispch.gob.cl/index.php/RISP/article/view/97 | Vol: 4 Issue: 1 | 0719-9317 | En un momento en que todo el mundo está esperando una vacuna contra el virus SARS-CoV-2, se cuenta una versión sintetizada de la historia de la producción de vacunas en Chile, siguiendo la huella que algunas han dejado a lo largo del tiempo. Este documento tiene como objetivo contribuir a la reflexión de cómo un país es capaz de producir sus medicamentos con voluntad y recursos propios, y comprender el desarrollo que hay detrás. | ||||
| Association between coal and firewood combustion and hospital admissions and mortality in Chile 2015 – An ecological approach | Annals of Agricultural and Environmental Medicine | Paredes, M.; Muñoz, M.; Valdés Salgado, M.; Maldonado, A. | 2020 | Ciudades Resilientes | 10.26444/aaem/125010 | http://www.journalssystem.com/aaem/Association-between-coal-and-firewood-combustion-and-hospital-admission-and-mortality,125010,0,2.html | 418–426 | Vol: 27 Issue: 3 | 1232-1966, 1898-2263 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Introduction and objective: Burning coal and firewood generates toxic emissions that are associated with respiratory illness, cardiovascular disease, and even death. The aim of the study is to evaluate the association between county-level prevalence of household coal and firewood use and health outcomes, including total, respiratory, and cardiovascular mortality, as well as total and respiratory hospitalization rates. Material and methods: The ecological study included data on the use of household coal and firewood in 139 counties obtained from the 2015 Chilean National Socio-economic Characterization Survey. Total, respiratory, and cardiovascular mortality, as well as total and respiratory hospitalization rates, were obtained from the Department of Health Statistics. Poisson models with robust error variance, Pearson linear correlation coefficients, and scatterplots were used to explore associations between household coal and firewood use and morbidity-mortality, stratifying by geographic zone. Results: Total, respiratory, and cardiovascular mortality and total and respiratory hospitalization rates were 5.7 per 1,000, 552 per 100,000, 157 per 100,000, 92.5 per 1000, and 8.8 per 1000 inhabitants, respectively. The median prevalence of coal use for residential cooking, heating, or water heating was 3.64%, while the median prevalence of firewood combustion was 12%. In southern counties, age- and gender-adjusted respiratory mortality increased 2.02 (95% CI: 1.17–3.50), 1.5 (95% CI: 1.11–1.89), and 1.76-fold (95% CI: 1.19–2.60) for each percentage increase in household coal and firewood use for heating, cooking and heating water, respectively. Conclusions: The prevalence of household coal and firewood used for heating and cooking was positively correlated with respiratory mortality and hospitalization in southern zone counties. |
| PM2.5 forecasting in Coyhaique, the most polluted city in the Americas | Urban Climate | Perez, P.; Menares, C.; Ramírez, C. | 2020 | Ciudades Resilientes | 10.1016/j.uclim.2020.100608 | https://doi.org/10.1016/j.uclim.2020.100608 | art: 100608 | Vol: 32 | 2212-0955 | Thomson Reuters ISI (SCIE) | English | Coyhaique is a southern Chilean city with a population of approximately 64,000 habitants. In spite of its small size, Coyhaique has been identified as the city with highest annual PM2.5 concentrations of the Americas (including south America, central America and north America). Episodes of high pollution are concentrated on the fall- winter season when meteorological conditions do not favor atmospheric particle dispersion and extended use of wood stoves is responsible for more than 99% of the emissions. In Chile, the 24 h average of PM2.5 concentration is classified in four ranges: fair, bad, very bad and critical. We have developed a neural network model and a linear model aimed to forecast the maximum of the 24 h moving average one day in advance. Input variables for the models are hourly values of PM2.5 at 18 h and 19 h of the present day, measured and forecasted temperature, wind speed and precipitation and measured values of NO2, CO and O3 concentrations. The neural network model is slightly more accurate than the linear model. We are able to anticipate the observed range in 75% of the cases, and critical days in 84% of the cases. © 2020 Elsevier B.V. | |
| Informe Proyecto ARClim: Atlas de Riegos Climáticos para Chile | Pica-Téllez, A.; Garreaud, R.; Meza, F.; Bustos, S.; Falvey, M.; Ibarra, M.; Silva, M.; Duarte, K.; Ormazábal, R.; Dittborn, R. | 2020 | Agua y Extremos | https://www.cr2.cl/informe-proyecto-arclim-atlas-de-riesgos-climaticos-para-chile/ | 193 | Spanish | Este documento, tiene por finalidad describir el proceso de desarrollo de la Plataforma ARClim, principal producto del proyecto “Atlas de Riesgo climático para Chile”, proyecto Apoyado por el Programa Mundial de Evaluación y Gestión de Riesgos para la Adaptación al Cambio Climático (Pérdidas y Daños)” por encargo del Ministerio Federal de Cooperación Económica y Desarrollo (BMZ) a través de la Agencia para la Cooperación Técnica GIZ (Deutsche Gesellschaft für Internationale Zusammenarbeit), con el objetivo de colaborar con el Ministerio de Medio Ambiente del Gobierno de Chile, aportando al fortalecimiento de las capacidades nacionales en el marco de los desafíos del Cambio Climático; generando Mapas de Riesgos de distintos sectores frente al Cambio Climático en el país. Para llevar a cabo este desafío, participaron 96 investigadores y 24 instituciones especializadas en distintas áreas del cambio climático, las que fueron liderados por el Centro de Ciencia del Clima y la Resiliencia (CR2 ) y el Centro de Cambio Global UC. | ||||||
| High Impact Weather Events in the Andes | Frontiers in Earth Science | Poveda, G.; Espinoza, J.; Zuluaga, M.; Solman, S.; Garreaud, R.; van Oevelen, P. | 2020 | Agua y Extremos | 10.3389/feart.2020.00162 | https://www.frontiersin.org/article/10.3389/feart.2020.00162/full | 162 | Vol: 8 | 2296-6463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Owing to the extraordinary latitudinal extent, a strong orographic variability with very high mountain tops, and the presence of deep valleys and steep slopes, the Andes and the population of the region are highly prone and vulnerable to the impacts of a large suite of extreme weather events. Here we provide a review of the most salient events in terms of losses of human and animal lives, economic and monetary losses in costs and damages, and social disruption, namely: (1) extreme precipitation events and related processes (Mesoscale Convective Systems, lightning), (2) cold spells, frosts, and high winds, (3) the impacts of ENSO on extreme hydro-meteorological events, (4) floods, (5) landslides, mudslides, avalanches, and (6) droughts, heat waves and fires. For our purposes, we focus this review on three distinctive regions along the Andes: Northern tropical (north of 8°S), Southern tropical (8°S-27°S) and Extratropical Andes (south of 27°S). Research gaps are also identified and discussed at the end of this review. It is very likely that climate change will increase the vulnerability of the millions of inhabitants of the Andes, impacting their livelihoods and the sustainable development of the region into the twenty first century amidst urbanization, deforestation, air, soil and water pollution, and land use changes. |
| Soil microbial community responses to labile organic carbon fractions in relation to soil type and land use along a climate gradient | Soil Biology and Biochemistry | Ramírez, P.; Fuentes-Alburquenque, S.; Díez, B.; Vargas, I.; Bonilla, C. | 2020 | Zonas Costeras | 10.1016/j.soilbio.2019.107692 | https://linkinghub.elsevier.com/retrieve/pii/S0038071719303566 | 107692 | Vol: 141 | 00380717 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | There has been a growing interest in studying the labile C pool in order to promote the sequestration and stabilization of soil organic carbon (SOC). Although labile SOC fractions have emerged as standardized indicators because of their potential to detect early SOC trends over time, the relationships between microbial attributes and labile SOC remains poorly understood. In this study, we explored the influence of labile SOC fractions on the topsoil bacteria-archaea community across 28 sites with different land use, climate aridity, and soil types across a wide range of SOC content (0.6–12%) in central Chile. We applied Illumina sequencing to the 16S rRNA to examine shifts in the diversity and composition of these soil microbial communities. Additionally, labile SOC fractions such as the permanganate oxidizable carbon (POXC) and light fraction organic matter (LFOM), along with the soil physicochemical properties were analyzed. The results demonstrated that among all of the environmental factors tested, the pH, POXC/SOC ratio and LFOM were key drivers of microbial community structure (β-diversity). The α-diversity metrics exhibited a decreasing trend when aridity increased, and community structure was found to vary, with high POXC/SOC in sites associated with drier conditions. In addition, POXC/SOC ratios and LFOM were clearly related to shifts in the relative abundances of specific taxonomic groups at genera level. When there was high POXC/SOC and low LFOM content, members of Bacteroidetes (Adhaeribacter, Flavisolibacter, and Niastella), Proteobacteria (Skermanella, Ramlibacter, and Sphingomonas), and Archaea (Thaumarchaeota) were found to be the most dominant groups; however, the microbial taxa responded differently to both labile C fraction types. These results have implications for understanding how labile C content can potentially be used to predict shifts in the microbial community, thus facilitating the development of predictive ecosystem models, as well as early warning indicators for soil degradation. |
| IPCC: The concept of risk in the IPCC Sixth Assessment Report: a summary of cross- Working Group discussions - Guidance for IPCC authors | Reisinger, A.; Garschagen, M.; Mach, K.; Pathak, M.; Poloczanska, E.; van Aalst, M.; Ruane, A.; Howden, M.; Hurlbert, M.; Mintenbeck, K.; Pedace, R.; Rojas, M.; Viner, D.; Vera, C.; Kreibiehl, S.; O'Neill, B.; Portner, H.; Sillmann, J.; Jones, R.; Ranasinghe, R. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.ipcc.ch/site/assets/uploads/2021/01/The-concept-of-risk-in-the-IPCC-Sixth-Assessment-Report.pdf | |||||||||
| Landscape restoration in a mixed agricultural-forest catchment: Planning a buffer strip and hedgerow network in a Chilean biodiversity hotspot | Ambio | Rey Benayas, J.; Altamirano, A.; Miranda, A.; Catalán, G.; Prado, M.; Lisón, F.; Bullock, J. | 2020 | Cambio de Uso de Suelo | 10.1007/s13280-019-01149-2 | http://link.springer.com/10.1007/s13280-019-01149-2 | 310-323 | Vol: 49 Issue: 1 | 0044-7447 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Guidance for large-scale restoration of natural or semi-natural linear vegetation elements that takes into account the need to maintain human livelihoods such as farming is often lacking. Focusing on a Chilean biodiversity hotspot, we assessed the landscape in terms of existing woody vegetation elements and proposed a buffer strip and hedgerow network. We used spatial analysis based on Google Earth imagery and QGIS, field surveys, seven guidelines linked to prioritization criteria and seedling availability in the region's nurseries, and estimated the budget for implementing the proposed network. The target landscapes require restoring 0.89 ha km-2 of woody buffer strips to meet Chilean law; 1.4 ha km-2 of new hedgerows is also proposed. The cost of restoration in this landscape is estimated in ca. USD 6900 per planted ha of buffer strips and hedgerows. Financial incentives, education, and professional training of farmers are identified as key issues to implement the suggested restoration actions. |
| Educación sobre el cambio climático en América Latina - El conocimiento genera justicia | Rojas, M. | 2020 | Gobernanza e Interfaz Ciencia y Política | https://www.siemens-stiftung.org/wp-content/uploads/medien/publikationen/publicacion-educacionsobreelcambioclimaticoenamericalatina-siemensstiftung.pdf | El cambio climático intensifica las crisis políticas y sociales Cada vez es más evidente que la brecha entre ricos y pobres se profundizará en las próximas décadas. Millones de personas vivirán bajo la línea de pobreza. En este contexto, uno de los mayores desafíos, también en América Latina, es el cambio climático que avanza más rápido de lo esperado. Probablemente, en los próximos diez años la temperatura aumentará más allá del 1,5 grados acordado provocando conse- cuencias imposibles de dimensionar. Debido a las sequías, las inundaciones y otros efectos del cambio climático muchos abandonarán sus hogares. Aumentará la migración, especialmente del campo hacia las ciudades, pero también más allá de las fronteras. Los riesgos de conflictos sociales son enormes. |
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| Results Report International Survey on Climate Change 2019 | Sapiains, R.; Ruette, J.; Urquiza, A.; Ugarte, A.; Rudnick, A.; Inostroza-Lazo, V.; García, M.; Bravo, M.; Sánchez, G.; Acevedo, J. | 2020 | https://www.statknows.com/sk-and-cr2-cclatam-resultsreport | 30 | The International Survey on Climate Change 2019 was a joint effort between StatKnows and the Center for Climate and Resilience Research, (CR)2. The study is statistically representative of the population over the age of 18 in Latin America as of November 2019, The survey included perceptions on the following topics: priority issues for each country; environmental issues that most affect personally; relationship between climate change and aspects of social justice; causes of climate change; predominant emotions associated with the concept of climate change; levels of concern about climate change; advocacy capacity; responsibility for its causes and solution; level of preparation of each country to deal with climate change; and information sources. |
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| Informe de resultados Encuesta Internacional de Cambio Climático 2019 | Sapiains, R.; Ruette, J.; Urquiza, A.; Ugarte, A.; Rudnick, A.; Inostroza-Lazo, V.; García, M.; Bravo, M.; Sánchez, G.; Acevedo, J. | 2020 | https://www.statknows.com/sk-and-cr2-cclatam-resultsreport | 30 | La Encuesta Internacional de Cambio Climático 2019 fue un esfuerzo conjunto entre StatKnows y el Centro de Ciencia del Clima y la Resiliencia, (CR)2. El estudio es estadísticamente representativo de la población mayor de 18 años de América Latina a noviembre de 2019, La encuesta incluyó percepciones sobre los siguientes temas: temas prioritarios para cada país; problemas ambientales que más afectan personalmente; relación entre el cambio climático y aspectos de justicia social; causas del cambio climático; emociones predominantes asociadas al concepto de cambio climático; niveles de preocupación por el cambio climático; capacidad de incidencia; responsabilidad por sus causas y solución; nivel de preparación de cada país para hacer frente al cambio climático; y fuentes de información. |
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| Local Perceptions of Fires Risk and Policy Implications in the Hills of Valparaíso, Chile | Sustainability | Sapiains, R.; Ugarte, A.; Aldunce, P.; Marchant, G.; Romero, J.; González, M.; Inostroza-Lazo, V. | 2020 | Agua y Extremos; Cambio de Uso de Suelo; Gobernanza e Interfaz Ciencia y Política | 10.3390/su12104298 | https://www.mdpi.com/2071-1050/12/10/4298 | 4298 | Vol: 12 Issue: 10 | 2071-1050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Climate change is increasing the occurrence of natural disasters worldwide, and more frequent and intense fires represent one of the most destructive expressions of this trend. Chile is highly vulnerable to climate change, and fires are a recurrent phenomenon affecting many people each year. To reduce fire risk, the Intergovernmental Panel on Climate Change (IPCC) suggests reducing both exposure and vulnerability through multiple initiatives, which demand increased community engagement. In such a context, this study explores local perceptions of fire in a sample of inhabitants in a wildland-urban interface (WUI) in Valparaiso, a city that is affected by numerous fires each year. The ultimate goal was to identify psychological and community factors that should be taken into consideration to develop prevention plans and safer environments for people living in a context of poverty and social inequity. Using a qualitative approach, 28 interviews were conducted and analyzed following grounded theory principles. Results identified multiple causes, impacts, and characteristics of the problem perceived by people who permanently cohabit with fire risk, showing that for many of them, fire risk is not about the probability of occurrence of a disaster, but a question about when and how the next fire will happen. However, in such a complex scenario, psychological, community, and structural barriers deter people from implementing more effective actions. Conversely, in emergency situations, such barriers are irrelevant and cooperative actions prevail, suggesting the existence of resources and capacities within the community that could lessen exposure and vulnerability if activated on a day-to-day basis. Overall, reducing fire risk cannot be achieved by local communities alone nor without their support. To build, maintain, and consolidate fire prevention actions, it is critical to activate community strengths and cooperation and engage the resources and management capacity of local governments. |
| Recent wildfires in Central Chile: Detecting links between burned areas and population exposure in the wildland urban interface | Science of The Total Environment | Sarricolea, P.; Serrano-Notivoli, R.; Fuentealba, M.; Hernández-Mora, M.; de la Barrera, F.; Smith, P.; Meseguer-Ruiz, Ó. | 2020 | Ciudades Resilientes | 10.1016/j.scitotenv.2019.135894 | https://linkinghub.elsevier.com/retrieve/pii/S0048969719358899 | 135894 | Vol: 706 | 00489697 | Thomson Reuters ISI (SCIE) | English | Wildfires are gaining importance in the Mediterranean regions owing to climate change and landscape changes due to the increasing closeness between urban areas and forests prone to wildfires. We analysed the dry season wildfire occurrences in the Mediterranean region of Central Chile (32°S–39°30′ S) between 2000 and 2017, using satellite images to detect burned areas, their landscape metrics and the land use and covers (vegetal) pre-wildfire, in order to determine the population living in areas that may be affected by wildfires. The existing regulations in western Mediterranean countries (Portugal, Spain, France, and Italy) were used to identify and define the wildland-urban interface (WUI) areas, quantifying the people inhabiting them and estimating the population affected by burned areas from 2001 to 2017. We used the Google Earth Engine to process MODIS products and extract both burned areas and land covers. We detected that 25% of the urban population inhabits WUI areas (i.e. Biobío, Araucanía and Valparaíso regions) where the urban population exposed to burned areas exceeds 40%. Most of the land use and land covers affected by wildfires are anthropogenic land covers, classified as savannas, croplands, evergreen broadleaf forests and woody savannas, representing >70% of the burned areas. Urban areas show only 0.6% of the burned surface from 2001 to 2017. We estimate that 55,680 people are potentially affected by wildfires, and 50% of them are in just one administrative region. These results show the imperative need for public policies as a regulating force for establishing WUI areas with the purpose of identifying wildfire risk in urban areas, such as establishing prevention methods as firewalls and prescribed fires. | |
| Two decades of ozone standard exceedances in Santiago de Chile | Air Quality, Atmosphere & Health | Seguel, R.; Gallardo, L.; Fleming, Z.; Landeros, S. | 2020 | Ciudades Resilientes | 10.1007/s11869-020-00822-w | http://link.springer.com/10.1007/s11869-020-00822-w | 593-605 | Vol: 13 Issue: 5 | 1873-9318, 1873-9326 | Thomson Reuters ISI (SCIE) | English | A drastic decline of 2.4 ppbv decade−1 in the ozone mixing ratio has been measured in Santiago de Chile during the 2000s. Subsequently, in the 2010s, ozone trends stabilized in downtown and showed upward trends in eastern Santiago. The number of days with an 8-h average ozone mixing ratio above 61 ppbv, deemed harmful to health according to Chilean legislation, has declined significantly both in western and central Santiago. However, in eastern Santiago, one finds a 2010–2018 decade average of 43 days per year above recommended levels. Also, at a Receptor Site located ~ 70 km downwind from Santiago, this number rose to up to 3 months per year. A common denominator for the last two decades has been a steady increase in both gasoline and diesel-powered private cars. In the 2010s, the ozone weekend effect was frequently noted, providing evidence that the ozone formation regime in Santiago is VOC-limited. Nitrogen oxides and carbon monoxide (a proxy of anthropogenic VOCs) have increased steadily since 2014 in a relatively constant CO-to-NOx ratio. Therefore, we propose that primary emissions of NOX and VOCs from motor vehicle exhaust have remained as the main driver of the photochemical air pollution in Santiago as well as explaining the weekly variation. Santiago, like other megacities in the world, faces several challenges associated with increasing urbanization as well as the effects of climate change. An increasing population, growth in private car use, and urban sprawl have contributed to maintain high levels of ozone. New threats such as increasing temperatures observed in the central valleys of Chile, along with more frequent occurrences of heat waves, whose number has doubled in the last decade, will require a different approach to manage ozone pollution during the next decade. Santiago will not meet its own goals in the upcoming years without implementing robust, scientifically sound, and cost-effective strategies designed specifically to tackle photochemical pollution. | |
| Recent changes in the precipitation-driving processes over the southern tropical Andes/western Amazon | Climate Dynamics | Segura, H.; Espinoza, J.; Junquas, C.; Lebel, T.; Vuille, M.; Garreaud, R. | 2020 | Agua y Extremos | 10.1007/s00382-020-05132-6 | http://link.springer.com/10.1007/s00382-020-05132-6 | 2613-2631 | Vol: 54 | 0930-7575, 1432-0894 | Thomson Reuters ISI (SCIE) | English | Analyzing December–February (DJF) precipitation in the southern tropical Andes—STA (12∘S–20∘S; > 3000 m.a.s.l) allows revisiting regional atmospheric circulation features accounting for its interannual variability over the past 35 years (1982–2018). In a region where in-situ rainfall stations are sparse, the CHIRPS precipitation product is used to identify the first mode of interannual DJF precipitation variability (PC1-Andes). A network of 98 rain-gauge stations further allows verifying that PC1-Andes properly represents the spatio-temporal rainfall distribution over the region; in particular a significant increase in DJF precipitation over the period of study is evident in both in-situ data and PC1-Andes. Using the ERA-Interim data set, we found that aside from the well-known relationship between precipitation and upper-level easterlies over the STA, PC1-Andes is also associated with upward motion over the western Amazon (WA), a link that has not been reported before. The ascent over the WA is a component of the meridional circulation between the tropical North Atlantic and western tropical South America—WTSA (80∘W–60∘W; 35∘S–10∘N). Indeed, the precipitation increase over the last 2 decades is concomitant with the strengthening of this meridional circulation. An intensified upward motion over the WA has moistened the mid-troposphere over WTSA, and as a consequence, a decreased atmospheric stability between the mid- and the upper troposphere is observed over this region, including the STA. We further show that, over the last 15 years or so, the year-to-year variability of STA precipitation (periodicity < 8 years) has been significantly associated with upward motion over the WA, while upper-level easterlies are no longer significantly correlated with precipitation. These observations suggests that the STA have experienced a transition from a dry to a wet state in association with a change in the dominant mode of atmospheric circulation. In the former dominant state, zonal advection of momentum and moisture from the central Amazon, associated with upper-level easterlies, is necessary to develop convection over the STA. Since the beginning of the 21st century, DJF precipitation over the STA seems to respond directly and primarily to upward motion over the WA. Beyond improving our understanding of the factors influencing STA precipitation nowadays, these results point to the need of exploring their possible implications for the long-term evolution of precipitation in a context of global warming. | |
| Tree-growth at the rear edge of a Nothofagus pumilio Andean forest from Northern Patagonia show different patterns and a decline in the common signal during the last century | Forest Ecology and Management | Serrano-León, H.; Christie, D. | 2020 | Agua y Extremos | 10.1016/j.foreco.2020.118426 | https://linkinghub.elsevier.com/retrieve/pii/S0378112720311956 | 118426 | Vol: 475 | 03781127 | Thomson Reuters ISI (SCIE) | English | Nothofagus pumilio is the dominant tree species at high elevations in the southern Andes between 35° and 55° S. Despite the number of tree-growth studies on this tree species, there is scarce information about the growth patterns and its relation with climatic variability at its lower elevation margin of distribution in the windward side of the Andes. In this study we focus on the altitudinal rear edge of a N. pumilio forest growing on the Pacific side of the northern Patagonian Andes to determine the main temporal patterns of tree radial growth, identify its relations with regional and large-scale climate and to assess the temporal variation of common signal in tree growth at centennial time-scales. A Principal Component Analysis (PCA) between trees for their common period 1850–2010 indicates the existence of more than one pattern of tree growth within this lower altitudinal margin, which exhibit contrasting relations with climate. The tree ring chronology and the PC1 amplitude of tree growth shows negative correlation with maximum temperature during spring-summer while the PC2 shows the contrary. Maps and correlation functions indicate that the PC1 and PC2 patterns of N. pumilio growth are significantly related with high latitude climate variability induced by the Antarctic Oscillation (AAO) during spring-summer in an opposite manner, with the PC1 (PC2) negatively (positively) correlated with the poleward displacement of the storm tracks driven by the mid- and high-latitude dipole pressure in the Southern Hemisphere. The running PCA between the standardized tree ring-width series shows a decreasing trend in the percentage of variance explained by the first mode of tree growth, indicating a centennial scale loss in the common signal of growth within the population, especially since mid-20th century when the behavior of the AAO was unprecedented within the context of the last millennium. Given that the future climatic scenario for northern Patagonia as predicted by models would led to more arid conditions forced by the positive trend of the AAO, we expect that the main pattern of N. pumilio growth at the rear edge of Choshuenco volcano will be negatively affected. Despite the present knowledge about N. pumilio radial growth in treeline environments, specific research is needed to gain insights about the complexity of the climate-growth relationship at its low elevation margin, in order to evaluate anomalies in tree growth patterns in the habitat where N. pumilio grows and competes with other low elevation species more tolerant to warmer conditions. |
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| Fermentation and Anaerobic Oxidation of Organic Carbon in the Oxygen Minimum Zone of the Upwelling Ecosystem Off Concepción, in Central Chile | Frontiers in Marine Science | Srain, B.; Sobarzo, M.; Daneri, G.; González, H.; Testa, G.; Farías, L.; Schwarz, A.; Pérez, N.; Pantoja-Gutiérrez, S. | 2020 | Zonas Costeras | 10.3389/fmars.2020.00533 | https://www.frontiersin.org/article/10.3389/fmars.2020.00533/full | 533 | Vol: 7 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | We studied the dynamics of fermentation and anaerobic degradation of organic matter at a fixed station in the Oxygen Minimum Zone (OMZ) within the Humboldt Current System off Concepción, central Chile. Products of the main anaerobic microbial reactions fermentation, denitrification, and reduction of Fe(OH)3 and SO42– were analyzed during laboratory incubations of OMZ waters. Fermentation of glucose and amino acids resulted in the production of volatile fatty acids, mainly acetate; these compounds were detected year-round in in situ water samples and were associated with high primary production rates and presence of O2-deficient waters at the sampling site. In contrast, whilst ethanol was produced from glucose fermentation by OMZ water microorganisms under laboratory conditions, it was not detected in the water column during the annual cycle. Evidence of acetate oxidation (which is thermodynamically feasible), with Fe(OH)3 as an electron acceptor, suggests that microbial activity could reduce solid-phase Fe carried by rivers using fermented metabolites in oxygen-depleted water, thus releasing dissolved bioavailable Fe. Here we present evidence for productivity-driven seasonality of biogeochemical cycles in the Humboldt system, supported by fermentation and anaerobic consumption of fermentation products oxidized by a variety of electron acceptors including NO3–, Fe(OH)3, and SO42–. Our results suggest that products of fermentation in the OMZ may provide a source of labile organics for advection to oxygenated waters of subantarctic origin during austral winter. Fermentation, anaerobic oxidation and associated advection of fermentation products are likely to be enhanced during the twenty-first century due both to temperature increase and decrease in dissolved O2 in the water column. |
| Differences in the composition of organic aerosols between winter and summer in Beijing: a study by direct-infusion ultrahigh-resolution mass spectrometry | Atmospheric Chemistry and Physics | Steimer, S.; Patton, D.; Vu, T.; Panagi, M.; Monks, P.; Harrison, R.; Fleming, Z.; Shi, Z.; Kalberer, M. | 2020 | Ciudades Resilientes | 10.5194/acp-20-13303-2020 | https://acp.copernicus.org/articles/20/13303/2020/ | 13303-13318 | Vol: 20 Issue: 21 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | This study investigates the chemical composition of PM2.5 collected at a central location in Beijing, China, during winter 2016 and summer 2017. The samples were characterised using direct-infusion negative-nano-electrospray-ionisation ultrahigh-resolution mass spectrometry to elucidate the composition and the potential primary and secondary sources of the organic fraction. The samples from the two seasons were compared with those from a road-tunnel site and an urban background site in Birmingham, UK, analysed in the course of an earlier study using the same method. There were strong differences in aerosol particle composition between the seasons, particularly regarding (poly-)aromatic compounds, which were strongly enhanced in winter, likely due to increased fossil fuel and biomass burning for heating. In addition to the seasonal differences, compositional differences between high- and low-pollution conditions were observed, with the contribution of sulfur-containing organic compounds strongly enhanced under high-pollution conditions. There was a correlation of the number of sulfur-containing molecular formulae with the concentration of particulate sulfate, consistent with a particle-phase formation process. |
| New Record of Hilophyllus martinezi Paulsen and Mondaca, 2006 (Coleoptera: Lucanidae: Aesalinae) in Southern Chile | Coleopterists Bulletin | Tello, F. | 2020 | Cambio de Uso de Suelo | 10.1649/0010-065X-74.2.424 | https://doi.org/10.1649/0010-065X-74.2.424 | 424-426 | Vol: 74 Issue: 2 | 0010-065X | Thomson Reuters ISI (SCIE) | English | ||
| First Record of the Family Histeridae (Insecta: Coleoptera) in a Late Pleistocene Sequence from Chile | Ameghiniana | Tello, F.; Arriagada, G.; Pino, M. | 2020 | Cambio de Uso de Suelo | 10.5710/AMGH.06.12.2019.3260 | https://doi.org/10.5710/AMGH.06.12.2019.3260 | 63-67 | Vol: 57 Issue: 1 | 0002-7014 | Thomson Reuters ISI (SCIE) | English | ||
| Diversity loss and changes in saproxylic beetle assemblages following a high-severity fire in Araucaria–Nothofagus forests | Journal of Insect Conservation | Tello, F.; González, M.; Valdivia, N.; Torres, F.; Lara, A.; García-López, A. | 2020 | Cambio de Uso de Suelo | 10.1007/s10841-020-00223-5 | http://link.springer.com/10.1007/s10841-020-00223-5 | 585-601 | Vol: 24 Issue: 3 | 1366-638X, 1572-9753 | Thomson Reuters ISI (SCIE) | English | Forest fires have increased in frequency worldwide due to global warming, drought, and land-use change. These fire-regime changes have altered the dynamics of deadwood accumulation in forests, which can affect biological communities dependent on this resource. We analyzed the effect of high-severity fire events on saproxylic beetle assemblages, which specialize in using deadwood that accumulates after disturbances. We compared assemblages in sites severely burned in 2002 to those in unburned sites in Chilean Araucaria–Nothofagus forests. Insects were collected using window-interception traps from spring 2017 to summer 2018. Rarefaction–interpolation curves revealed a significant decrease in diversity as a result of fire. Permutational multivariate analysis of variance showed a significant effect of fire on insect community structure. In addition, we observed that species turnover contributing most, and nestedness to a lesser extent, to differences in ß-diversity between burned and unburned sites. Species replacement was associated with an increase in abundance of xylophagous (deadwood feeders) and a decrease in abundance of mycophagous (fungivorous) insects with fire. Therefore, our results suggest that fire causes a reduction in diversity while benefiting the abundance of xylophagous beetles in Araucaria–Nothofagus forests. We recommend the use of these insects as an evaluation tool in conservation planning, management practices, and ecological restoration efforts in burned forests in southern Chile. | |
| Sub-oxycline methane oxidation can fully uptake CH4 produced in sediments: case study of a lake in Siberia | Scientific Reports | Thalasso, F.; Sepulveda-Jauregui, A.; Gandois, L.; Martinez-Cruz, K.; Gerardo-Nieto, O.; Astorga-España, M.; Teisserenc, R.; Lavergne, C.; Tananaev, N.; Barret, M.; Cabrol, L. | 2020 | Cambio de Uso de Suelo | 10.1038/s41598-020-60394-8 | http://www.nature.com/articles/s41598-020-60394-8 | 3423 | Vol: 10 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | It is commonly assumed that methane (CH4) released by lakes into the atmosphere is mainly produced in anoxic sediment and transported by diffusion or ebullition through the water column to the surface of the lake. In contrast to that prevailing idea, it has been gradually established that the epilimnetic CH4 does not originate exclusively from sediments but is also locally produced or laterally transported from the littoral zone. Therefore, CH4 cycling in the epilimnion and the hypolimnion might not be as closely linked as previously thought. We utilized a high-resolution method used to determine dissolved CH4 concentration to analyze a Siberian lake in which epilimnetic and hypolimnetic CH4 cycles were fully segregated by a section of the water column where CH4 was not detected. This layer, with no detected CH4, was well below the oxycline and the photic zone and thus assumed to be anaerobic. However, on the basis of a diffusion-reaction model, molecular biology, and stable isotope analyses, we determined that this layer takes up all the CH4 produced in the sediments and the deepest section of the hypolimnion. We concluded that there was no CH4 exchange between the hypolimnion (dominated by methanotrophy and methanogenesis) and the epilimnion (dominated by methane lateral transport and/or oxic production), resulting in a vertically segregated lake internal CH4 cycle. |
| El Formativo en Tarapacá (3000-1000 aP): Arqueología, naturaleza y cultura en la Pampa del Tamarugal, Desierto de Atacama, norte de Chile | Latin American Antiquity | Uribe, M.; Angelo, D.; Capriles, J.; Castro, V.; de Porras, M.; García, M.; Gayo, E.; González, J.; Herrera, M.; Izaurieta, R.; Maldonado, A.; Mandakovic, V.; McRostie, V.; Razeto, J.; Santana, F.; Santoro, C.; Valenzuela, J.; Vidal, A. | 2020 | Ciudades Resilientes | 10.1017/laq.2019.92 | https://www.cambridge.org/core/product/identifier/S1045663519000920/type/journal_article | 81-102 | Vol: 31 Issue: 1 | 1045-6635, 2325-5080 | Thomson Reuters ISI (SSCI; AHCI) | Spanish | In this article, we illustrate the relationships that human societies established with their environment during the Formative period in the Pampa del Tamarugal (3000–1000 BP), Atacama Desert, Chile. We employed a theoretical-methodological perspective that emphasizes the explanatory potential of ecofacts. By mediating between humans and environment, this perspective provides a better understanding of how these societies constructed nature and culture. The purpose is to show that this process was part of a long history of rationalization of the desert, its resources, and the lived experience of the Formative communities that occupied that landscape. Therefore, we propose that this human intervention in Pampa del Tamarugal can be understood not only as an ecological and economic change but also a “cosmological” one. | |
| Water markets and social–ecological resilience to water stress in the context of climate change: an analysis of the Limarí Basin, Chile | Environment, Development and Sustainability | Urquiza, A.; Billi, M. | 2020 | Ciudades Resilientes | 10.1007/s10668-018-0271-3 | http://link.springer.com/10.1007/s10668-018-0271-3 | 1929–1951 | Vol: 22 | 1387-585X, 1573-2975 | Thomson Reuters ISI (SCIE) | English | The paper proposes an analysis of the social–ecological resilience of the Limarí Basin, an agriculture-intensive dryland in the north of Chile, featuring one of the most innovative market-based water managements and the most active water rights market in the country, but concurrently affected by an ongoing water stress situation. The Chilean water market, one of the main examples of the application of neoliberal policies in water management, has received mixed appraisals although, at present, few empirical studies evaluate the social and environmental conditions associated with their operation. This paper, on the contrary, maintains the necessity to assess the capacity of market-based models to face situations of water stress, particularly since mega-drought phenomena are projected to become a recurring and increasing problem during the following decades because of climate change. The study offers a mixed bottom-up and top-down qualitative empirical analysis of how the Chilean water market operates, providing relevant insights into four dimensions of the social–ecological resilience of the watershed: redundancy, diversity and flexibility; connectivity, collaboration and collective action; social–ecological memory and learning; self-organization and governance of system changes. The conclusion is that water scarcity is self-produced: despite the flexibility provided by market-based water management, the combined effect of strong deregulation, of the absence of territorial planning and integrated management of water resources, and of short-term attitudes and generalized mistrust, has led the system to the critical situation it is now facing. | |
| Seguridad hídrica y energética en América Latina y el Caribe: definición y aproximación territorial para el análisis de brechas y riesgos de la población | Urquiza, A.; Billi, M. | 2020 | Ciudades Resilientes | https://www.cepal.org/es/publicaciones/46408-seguridad-hidrica-energetica-america-latina-caribe-definicion-aproximacion | 133 | Spanish | La crisis sanitaria provocada por la propagación del COVID-19 se superpone a otros complejos desafíos ya existentes en América Latina y el Caribe, como poner fin a la pobreza en sus múltiples formas o la necesidad de adoptar medidas urgentes para combatir el cambio climático y sus efectos. En este contexto es crucial distinguir cómo estas problemáticas tensionan el funcionamiento de servicios fundamentales para la salud y el desarrollo humano, como lo son los servicios hídricos y energéticos en la región. Al respecto, en este informe se abordan al menos tres dimensiones del problema, tal como se explica a continuación. |
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| Informe Proyecto ARClim: Asentamientos Humanos. Centro de Ciencia del Clima y la Resiliencia , Red de Pobreza Energética, Iniciativa ENEAS: Energía, Agua y Sustentabilidad y Núcleo de Estudios Sistémicos Transdisciplinarios | Urquiza, A.; Billi, M.; Calvo, R.; Amigo, C.; Navea, J.; Monsalve, T.; Álamos, N.; Neira, C.; Rauld, J.; Allendes, Á.; Arrieta, D.; Barrera, V.; Basoalto, J.; Cárdenas, M.; Contreras, M.; Fleischmann, M.; Horta, D.; Labraña, J.; Larragubel, C.; Muñoz, A.; Oyarzún, T.; Palacios, G.; Peña, D.; Plass, ... | 2020 | Ciudades Resilientes | Spanish | |||||||||
| Low Growth Sensitivity and Fast Replenishment of Non-structural Carbohydrates in a Long-Lived Endangered Conifer After Drought | Frontiers in Plant Science | Urrutia-Jalabert, R.; Lara, A.; Barichivich, J.; Vergara, N.; Rodriguez, C.; Piper, F. | 2020 | Cambio de Uso de Suelo | 10.3389/fpls.2020.00905 | https://www.frontiersin.org/article/10.3389/fpls.2020.00905/full | 905 | Vol: 11 | 1664-462X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | There is an ongoing debate on whether a drought induced carbohydrate limitation (source limitation) or a direct effect of water shortage (sink limitation) limit growth under drought. In this study, we investigated the effects of the two driest summers recorded in southern Chile in the last seven decades, on the growth and non-structural carbohydrates (NSC) concentrations of the slow-growing conifer Fitzroya cupressoides. Specifically, we studied the seasonal variation of NSC in saplings and adults one and two years after the occurrence of a 2 year-summer drought at two sites of contrasting precipitation and productivity (mesic-productive vs. rainy-less productive). We also evaluated radial growth before, during and after the drought, and predicted that drought could have reduced growth. If drought caused C source limitation, we expected that NSCs will be lower during the first than the second year after drought. Conversely, similar NSC concentrations between years or higher NSC concentrations in the first year would be supportive of sink limitation. Also, due to the lower biomass of saplings compared with adults, we expected that saplings should experience stronger seasonal NSC remobilization than adults. We confirmed this last expectation. Moreover, we found no significant growth reduction during drought in the rainy site and a slightly significant growth reduction at the mesic site for both saplings and adults. Across organs and in both sites and age classes, NSC, starch, and sugar concentrations were generally higher in the first than in the second year following drought, while NSC seasonal remobilization was generally lower. Higher NSC concentrations along with lower seasonal NSC remobilization during the first post-drought year are supportive of sink limitation. However, as these results were found at both sites while growth decreased slightly and just at the mesic site, limited growth only is unlikely to have caused NSC accumulation. Rather, these results suggest that the post-drought dynamics of carbohydrate storage are partly decoupled from the growth dynamics, and that the rebuild of C reserves after drought may be a priority in this species. |
| Environmental costs of water transfers | Nature Sustainability | Vargas, C.; Garreaud, R.; Barra, R.; Vásquez-Lavin, F.; Saldías, G.; Parra, O. | 2020 | Agua y Extremos | 10.1038/s41893-020-0526-5 | http://www.nature.com/articles/s41893-020-0526-5 | 408-409 | Vol: 3 Issue: 6 | 2398-9629 | Thomson Reuters ISI (SCIE; SSCI) | English | Central Chile (30–37° S) is home to ∼10 million inhabitants and hosts intensive agriculture, mining, forestry and electricity generation. These activities are already constrained by limited freshwater availability in this semi-arid region that has been regularly affected by short-lived (<3 years) but intense (>50% rainfall deficit) droughts in the past. More recently, a large portion of this territory has experienced a megadrought, an uninterrupted sequence of dry years since 2010, partially driven by climate change1. Model-based climate projections for the rest of twenty-first century suggest a poleward expansion of the Hadley cell and the arid belt, thus causing further warming and drying across most of Mediterranean regions of the world, including central Chile, southern Africa and parts of western North America and Australia. Under a heavy carbon emission scenario, annual precipitation in central Chile would reduce by up to 30%, and mean temperature would increase up to 2.5 °C2. These trends would further decrease freshwater availability. The present and future acute shortages in freshwater access in different regions worldwide, such as in central Chile, have led some private initiatives to propose water diversion from the more humid south-central part of the country (Fig. 1). These ‘hydrological roads’ involve large-scale capture, storage and transfer of freshwater across 2,000 km. One argument to justify such proposals in different regions of the planet is that freshwater is wasted when it reaches the sea. However, many studies recognize that riverine influxes of organic matter and nutrients exported from rivers are extremely important for supporting coastal biological productivity and biogeochemical cycles3. For instance, the Maule, Rapel and Biobío rivers in Chile export hundreds of tons of nitrogen, and thousands of tons of silicon and carbon4 daily, which could contribute to a significant fraction of the high fish biomass typically recorded along Chilean coast. | |
| Geo-climatic hazards in the eastern subtropical Andes: distribution, climate drivers and trends | Natural Hazards and Earth System Sciences | Vergara, I.; Moreiras, S.; Araneo, D.; Garreaud, R. | 2020 | Agua y Extremos | 10.5194/nhess-20-1353-2020 | https://www.nat-hazards-earth-syst-sci.net/20/1353/2020/ | 1353-1367 | Vol: 20 Issue: 5 | 1684-9981 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Detecting and understanding historical changes in the frequency of geo-climatic hazards (G-CHs) is crucial for the quantification of current hazards and project them into the future. Here we focus in the eastern subtropical Andes (32–33∘ S), using meteorological data and a century-long inventory of 553 G-CHs triggered by rainfall or snowfall. We first analyse their spatio-temporal distributions and the role of climate variability in the year-to-year changes in the number of days per season with G-CHs. Precipitation is positively correlated with the number of G-CHs across the region and year-round; mean temperature is negatively correlated with snowfall-driven hazards in the western (higher) half of the study region during winter and with rainfall-driven hazards in the eastern zone during summer. The trends of the G-CH frequency since the mid-20th century were calculated, paying attention to their non-systematic monitoring. The G-CH series for the different triggers, zones and seasons were generally stationary. Nonetheless, there is a small positive trend in rainfall-driven G-CHs in the eastern zone during summer, congruent with a rainfall increase there. We also found a decrease in snowfall-driven G-CHs in the western zone from the late 1990s onwards, most likely due to a reduction in winter precipitation rather than to an increase in temperature. |
| The influence of early experiences and university environment for female students choosing geoscience programs: a case study at Universidad de Chile | Advances in Geosciences | Villaseñor, T.; Celis, S.; Queupil, J.; Pinto, L.; Rojas, M. | 2020 | 10.5194/adgeo-53-227-2020 | https://adgeo.copernicus.org/articles/53/227/2020/ | 227-244 | Vol: 53 | 1680-7359 | All Open Access; Gold Open Access | English | Abstract. This case study addresses the experiences of female undergraduate students in the geology and geophysics programs at Universidad de Chile. These majors are part of the Faculty of Physical Sciences and Mathematics (FCFM) and have a relatively large proportion of female representation compared to the other engineering and science majors at FCFM that are dominated by male students. We interviewed 12 female students in geoscience majors to understand (a) the reasons for choosing geoscience as a major and (b) their experiences both at FCFM and in geoscience in an institution with a strong masculine environment that aims to increase women's undergraduate enrollment. We found that the decision to pursue a geoscience career was made during high school, and they maintained this decision during the first years of college, which is heavily focused on mathematics and physics, with no geoscience-related courses. During this early period in college, known as the common core program, students perceived a hostile environment due to high academic demands and gender-based discrimination. Their experiences had a positive shift once they started the geoscience courses in their fifth or sixth semester. The relatively large proportion of female students in the geoscience majors at FCFM creates a positive environment in which the participants developed a sense of belonging in the geoscience community. Students also felt that the feminist movement during 2018 in Chile positively influenced their perspectives on their path at FCFM. These findings give insights for developing strategies to increase early interest, participation, and satisfaction of women in science, technology, engineering, and mathematics (STEM) disciplines at various educational levels. | ||
| Firewood certification programs: Key attributes and policy implications | Energy Policy | Vásquez-Lavin, F.; Barrientos, M.; Castillo, Á.; Herrera, I.; Ponce Oliva, R. | 2020 | Cambio de Uso de Suelo | 10.1016/j.enpol.2019.111160 | https://linkinghub.elsevier.com/retrieve/pii/S0301421519307463 | 111160 | Vol: 137 | 0301-4215 | Thomson Reuters ISI (SCIE; SSCI) | English | Evidence from south-central Chile shows that the concentration limits for PM10 and PM2.5, defined by both the World Health Organization and national standards, are systematically exceeded, affecting approximately 10 million people. Among the sources of this pollution, firewood use accounts for the largest share. This study assesses whether consumers value environmental, social, and legal attributes associated with the firewood certification programs. We used a discrete choice model based on a sample of 500 households. According to our results, the price premium for certified firewood is about 10% in the most likely scenario, with those attributes closely related to private benefits having a higher value, compared to those of social benefits. We identify significant heterogeneity among respondents belonging to two different consumer classes: 1) those who are less price sensitive and are willing to pay for attributes related to certification; 2) those who are sensitive to prices and are not willing to pay for attributes related to certification. Since the second class includes about 46% of the sample, the implementation of certification programs could be jeopardized. Therefore, knowing this information helps us determine whether a certification system can foster the firewood industry transition to a more sustainable model. | |
| Water demand in the Chilean manufacturing industry: Analysis of the economic value of water and demand elasticities | Water Resources and Economics | Vásquez-Lavín, F.; Vargas O, L.; Hernández, J.; Ponce Oliva, R. | 2020 | Cambio de Uso de Suelo | 10.1016/j.wre.2020.100159 | https://linkinghub.elsevier.com/retrieve/pii/S2212428420300049 | 100159 | Vol: 32 | 22124284 | Thomson Reuters ISI (SCIE; SSCI) | English | In this article, we estimate both the economic value of water and own-price and cross-price elasticities of water for the Chilean manufacturing industry using the production function approach. Estimating the production function allows us to estimate the marginal productivity of water which corresponds to its economic value. Our estimations are based on panel data obtained from the National Industrial Survey for the period 1995–2014, accounting for more than 10,000 industrial plants. We use a translog specification for the production function, considering water, capital, labor, energy, and intermediate material as explanatory variables. We find substitution patterns among most inputs, except for energy and water, which are found to be complements. Our results suggest that the manufacturing sector is characterized by an elastic water demand, with an average economic value of water of 8.071 [USD/m3]. Based on our findings, there is room to increase water prices in most sectors without affecting the competitiveness of firms. Knowing the economic value of water and its price elasticity could help policymakers to design water policies that promote more efficient use of this scarce resource. | |
| Ideas and perspectives: A strategic assessment of methane and nitrous oxide measurements in the marine environment | Biogeosciences | Wilson, S.; Al-Haj, A.; Bourbonnais, A.; Frey, C.; Fulweiler, R.; Kessler, J.; Marchant, H.; Milucka, J.; Ray, N.; Suntharalingham, P.; Thornton, B.; Upstill-Goddard, R.; Weber, T.; Arévalo-Martínez, D.; Bange, H.; Benway, H.; Bianchi, D.; Borges, A.; Chang, B.; Crill, P.; del Valle, D.; Farías, L.;... | 2020 | Zonas Costeras | 10.5194/bg-17-5809-2020 | https://bg.copernicus.org/articles/17/5809/2020/ | 5809-5828 | Vol: 17 Issue: 22 | 1726-4189 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Abstract. In the current era of rapid climate change, accurate characterization of climate-relevant gas dynamics – namely production, consumption, and net emissions – is required for all biomes, especially those ecosystems most susceptible to the impact of change. Marine environments include regions that act as net sources or sinks for numerous climate-active trace gases including methane (CH4) and nitrous oxide (N2O). The temporal and spatial distributions of CH4 and N2O are controlled by the interaction of complex biogeochemical and physical processes. To evaluate and quantify how these mechanisms affect marine CH4 and N2O cycling requires a combination of traditional scientific disciplines including oceanography, microbiology, and numerical modeling. Fundamental to these efforts is ensuring that the datasets produced by independent scientists are comparable and interoperable. Equally critical is transparent communication within the research community about the technical improvements required to increase our collective understanding of marine CH4 and N2O. A workshop sponsored by Ocean Carbon and Biogeochemistry (OCB) was organized to enhance dialogue and collaborations pertaining to marine CH4 and N2O. Here, we summarize the outcomes from the workshop to describe the challenges and opportunities for near-future CH4 and N2O research in the marine environment. |
| Evidence of climate-driven changes on atmospheric, hydrological, and oceanographic variables along the Chilean coastal zone | Climatic Change | Winckler-Grez, P.; Aguirre, C.; Farías, L.; Contreras-López, M.; Masotti, Í. | 2020 | Zonas Costeras | 10.1007/s10584-020-02805-3 | http://link.springer.com/10.1007/s10584-020-02805-3 | 633-652 | Vol: 163 Issue: 2 | 0165-0009, 1573-1480 | Thomson Reuters ISI (SCIE) | English | The Chilean coastal zone (CCZ) is subjected to a complex spectrum of anthropogenic, geophysical, biogeochemical, and climate-driven perturbations. Potentially affected variables including atmospheric sea level pressure ( Pa ), alongshore wind, sea surface temperature ( SST ), chlorophyll-a, rainfall, river discharge, relative mean sea level ( RMSL ), and wave climate are studied using in situ and satellite records, hindcasts, and reanalysis datasets. Linear temporal trends and correlations of anomalies are estimated between 18°S and 55°S along the CCZ. The comparison of some of the variables is achieved by means of a strict homogenization procedure on a monthly basis for 35 years. Our findings show that the poleward drift and strengthening of the Southeast Pacific Subtropical Anticyclone (SPSA) partially explains the increase in Pa and reduction in rainfall and river discharge. The enhancement of alongshore winds, also attributable to changes in the SPSA, increases coastal upwelling, which in turn could reduce SST and increase chlorophyll-a. Despite differential latitudinal responses, increasing wave heights and a southward rotation are evidenced. RMSL does not show significant variation as it is presumably affected by seafloor changes during the seismic cycle. Though some correlations are evidenced, the influence of climate variability at decadal scale (PDO, SAM) may be affecting the detected trends due to the short length of available data. Impacts on coastal communities, infrastructure, and ecosystems are discussed, aiming to highlight that coastal vulnerabilities and risk management should be based on the cumulative impacts of these variables. |
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| Landscape evolution and the environmental context of human occupation of the southern pampa del tamarugal, Atacama Desert, Chile | Quaternary Science Reviews | Workman, T.; Rech, J.; Gayó, E.; Santoro, C.; Ugalde, P.; De Pol-Holz, R.; Capriles, J.; Latorre, C. | 2020 | Ciudades Resilientes | 10.1016/j.quascirev.2020.106502 | https://linkinghub.elsevier.com/retrieve/pii/S0277379120304649 | 106502 | Vol: 243 | 02773791 | Thomson Reuters ISI (SCIE) | English | As with most living organisms, human populations respond to climatic, environmental, and population pressures by transforming their range and subsistence strategies over space and time. An understanding of human ecology can be gained when the archaeological record is placed within the context of dynamic landscape changes and alterations in natural resource availability. We reconstructed the landscape evolution of the Quebrada Maní fan complex, situated along the west-facing slope of the Central Andes in the hyperarid core of the Atacama Desert, an area that contains an archaeological record that spans almost 13,000 years. Surficial geologic mapping and dating of three 2–12 km2 study sites, in conjunction with archaeological records and analysis of remotely sensed data for the ∼400 km2 fan complex, was conducted to reconstruct the landscape evolution and the way of life of Paleoindian (ca. 12.8–11.5 ka) and early/late Formative (ca 2.5 to 0.7 ka) social groups. Just prior to any known human occupation, a large pluvial event in the high Andes, regionally referred to as CAPE I, impacted the Quebrada Maní fan complex from ca.18–16.5 ka. During CAPE I, the Maní fan complex was dominated by perennial stream systems that deposited well-sorted conglomerates in the upper reaches of the fan (Unit T2) and perennial wetlands (Unit B1). This pluvial period was followed by the onset of an extreme drought sometime after 15 ka, but before 13 ka, when wetlands desiccated and the distal reaches of the fan deflated. Sand sheets and sand dunes were deposited across broad reaches of the landscape and Quebrada Maní incised 3–5 m into its floodplain. This drought had profound implications for the distribution of natural resources during the subsequent pluvial event (CAPE II) that ensued from ca. 12.5–9.5 ka. Incision along the upper reaches of the fan caused a more restricted floodplain and allowed the deposition of extensive wetlands along the more distal central reaches of the fan where groundwater emerged. Paleoindian residential open-air camps were placed in these areas. Wetlands were replaced by a tree-covered floodplain during the latter portion of this pluvial event (ca. 10.5–9 ka). We found no archaeological evidence for human occupations between ∼8–2.5 ka, suggesting a lack of natural resources and/or very low hunter-gatherer population densities. During this time, Quebrada Maní incised up to 8 m into the floodplain. Mudflow deposition – typical of the present-day fan complex – initiated around 2.5 ka, likely responding to an increase in precipitation. This triggered a re-population of the fan surface by Formative agricultural groups that irrigated and extensively farmed these floodplains. By the end of the Formative, these socio-cultural groups became increasingly vulnerable to climatic changes as cut-and-fill cycles in the drainage necessitated major infrastructure adjustments, until the technologies and social-cultural convention of the epoch could not cope with environmental change and investments were abandoned by ∼0.8 ka. |
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| RedPE (2020). Caracterización del mercado de la leña en Chile y sus barreras para la transición energética | Álamos, N.; Amigo, C.; Calvo, R.; Chahúan, J.; Correa, V.; Cortés, J.; Labraña, J.; Urquiza, A. | 2020 | Ciudades Resilientes | http://redesvid.uchile.cl/pobreza-energetica/wp-content/uploads/2020/12/VF.07-dic.Mercado-de-la-len%CC%83a.pdf | En Chile más de la mitad de sus habitantes están expuestos a concentraciones de material particulado fino (MP2,5)1 por sobre los límites recomendados por la Organización Mundial de la Salud, llegando a la situación que nueve de las quince ciudades más contaminadas por MP2,5 de América Latina están en el centro y sur del país (IQ Air, 2018). Considerando este antecedente, el Estado ha actuado generando políticas públicas orientadas a proteger la salud de la población, fortaleciendo y revisando la normativa ambiental actual y vigilando la implementación y desarrollo de Planes de Prevención y Descontaminación Atmosférica (PPDA). En este contexto, se ha prestado atención a la principal fuente emisora causante de la contaminación atmosférica en la zona centro sur del país: el consumo de leña residencial |
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| The glass half-empty: climate change drives lower freshwater input in the coastal system of the Chilean Northern Patagonia | Climatic Change | Aguayo, R.; León-Muñoz, J.; Vargas-Baecheler, J.; Montecinos, A.; Garreaud, R.; Urbina, M.; Soto, D.; Iriarte, J. | 2019 | Agua y Extremos | 10.1007/s10584-019-02495-6 | http://link.springer.com/10.1007/s10584-019-02495-6 | 417-435 | Vol: 155 Issue: 3 | 0165-0009 | Thomson Reuters ISI (SCIE) | English | Oceanographic conditions in coastal Chilean northern Patagonia (41–46°S) are strongly influenced by freshwater inputs. Precipitation and streamflow records have shown a marked decrease in this area during the last decades. Given this hydro-climatic scenario, we evaluated the hydrological sensitivity driven by climate change in the Puelo River (average annual streamflow = 640 m³ s⁻¹), one of the most important sources of freshwater in the fjords and inland seas of Chile’s Northern Patagonia. A lumped hydrological model was developed to evaluate the potential impacts of climate change under the Representative Concentration Pathways (RCP) 2.6, 4.5, and 8.5 scenarios in the near future (2030–2060) using the delta change method based on 25 General Circulation Models. The model was fed by local hydro-meteorological data and remote sensors, simulating well the magnitude and seasonality of Puelo River streamflow. Considering the Refined Index of Agreement (RIA), the model achieved a high performance in the calibration (RIA = 0.79) and validation stages (RIA = 0.78). Under the RCP 8.5 scenario (multi-model mean), the projections suggest that the annual input of freshwater from the Puelo River to the Reloncaví Fjord would decrease by − 10% (1.6 km³ less freshwater); these decreases would mainly take place in summer (~ − 20%) and autumn (~ − 15%). The recurrence of extreme hydroclimatic events is also projected to increase in the future, with the probability of occurrence of droughts, such as the recent 2016 event with the lowest freshwater input in the last 70 years, doubling with respect to the historical records. | |
| Role of synoptic activity on projected changes in upwelling-favourable winds at the ocean’s eastern boundaries | npj Climate and Atmospheric Science | Aguirre, C.; Rojas, M.; Garreaud, R.; Rahn, D. | 2019 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | 10.1038/s41612-019-0101-9 | http://www.nature.com/articles/s41612-019-0101-9 | 44 | Vol: 2 Issue: 1 | 2397-3722 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The climate of the ocean’s eastern boundaries is strongly influenced by subtropical anticyclones, which drive a surface wind stress that promotes coastal upwelling of nutrient-rich subsurface water that supports high primary productivity and an abundance of food resources. Understanding the projected response of upwelling-favourable winds to climate change has broad implications for coastal biogeochemistry, ecology, and fisheries. Here we use a reanalysis, an ensemble of global climate simulations, and an objective algorithm to track anticyclones to investigate the projected changes in upwelling-favourable wind events at the California, Canary, Humboldt, and Benguela coastal upwelling systems. Except for the north Pacific, we find consistent poleward shifts of mean and upper percentile daily winds over the ocean basins. We propose that extratropical, synoptic-scale migratory anticyclones that force intense coastal upwelling events—which become more frequent at higher latitudes and less frequent at lower latitudes in the future—play an important role in the projected changes in upwelling-favourable wind events in these coastal upwelling systems. These changes complement large-scale processes such as the poleward shift of the subtropical ridge (STR) and stationary subtropical highs. Hence, both extratropical and tropical processes need to be considered to fully explain projected changes at the coastal upwelling systems under anthropogenic climate change. |
| Operationalizing the IUCN Red List of Ecosystems in public policy | Conservation Letters | Alaniz, A.; Pérez‐Quezada, J.; Galleguillos, M.; Vásquez, A.; Keith, D. | 2019 | Cambio de Uso de Suelo | 10.1111/conl.12665 | https://onlinelibrary.wiley.com/doi/abs/10.1111/conl.12665 | art: e12665 | Vol: 12 Issue: 5 | 1755-263X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Threats to ecosystems are closely linked to human development, whereas lack, insufficiency, and inefficiency of public policies are important drivers of environmental decline. Previous studies have discussed the contribution of IUCN's Red List of Ecosystems (RLE) in conservation issues; however, its applications in different policy fields and instruments for achieving biodiversity conservation have not been explored in detail. Here, we introduce a framework to operationalize the RLE in public policy, facilitating work of governments, practitioners, and decision makers. Our analysis identified 20 policy instruments that could reduce risks to ecosystems highlighted by different Red List criteria. We discuss how RLE could inform the policy process by analyzing different instruments that could be designed, implemented, and modified to achieve risk reduction. We also present practical examples from around the world showing how ecosystem conservation could be improved by operationalizing the RLE in policy instruments. The RLE criteria can inform the policy process by helping to shape objectives and identifying policy instruments that directly address the causes and severity of risks illuminated in Red List assessments. We conclude that RLE could be expanded into a broader holistic spectrum of policy instruments, which could be a key to achieving the ecosystem conservation. |
| Elucidating Viral Communities During a Phytoplankton Bloom on the West Antarctic Peninsula | Frontiers in Microbiology | Alarcón-Schumacher, T.; Guajardo-Leiva, S.; Antón, J.; Díez, B. | 2019 | Zonas Costeras | 10.3389/fmicb.2019.01014 | https://www.frontiersin.org/article/10.3389/fmicb.2019.01014/full | 1014 | Vol: 10 | 1664-302X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In Antarctic coastal waters where nutrient limitations are low, viruses are expected to play a major role in the regulation of bloom events. Despite this, research in viral identification and dynamics is scarce, with limited information available for the Southern Ocean (SO). This study presents an integrative-omics approach, comparing variation in the viral and microbial active communities on two contrasting sample conditions from a diatom-dominated phytoplankton bloom occurring in Chile Bay in the West Antarctic Peninsula (WAP) in the summer of 2014. The known viral community, initially dominated by Myoviridae family (∼82% of the total assigned reads), changed to become dominated by Phycodnaviridae (∼90%), while viral activity was predominantly driven by dsDNA members of the Phycodnaviridae (∼50%) and diatom infecting ssRNA viruses (∼38%), becoming more significant as chlorophyll a increased. A genomic and phylogenetic characterization allowed the identification of a new viral lineage within the Myoviridae family. This new lineage of viruses infects Pseudoalteromonas and was dominant in the phage community. In addition, a new Phycodnavirus (PaV) was described, which is predicted to infect Phaeocystis antarctica, the main blooming haptophyte in the SO. This work was able to identify the changes in the main viral players during a bloom development and suggests that the changes observed in the virioplankton could be used as a model to understand the development and decay of blooms that occur throughout the WAP. © 2019 Alarcón-Schumacher, Guajardo-Leiva, Antón and Díez. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. |
| Fischerella thermalis: a model organism to study thermophilic diazotrophy, photosynthesis and multicellularity in cyanobacteria | Extremophiles | Alcorta, J.; Vergara-Barros, P.; Antonaru, L.; Alcamán-Arias, M.; Nürnberg, D.; Díez, B. | 2019 | Zonas Costeras | 10.1007/s00792-019-01125-4 | http://link.springer.com/10.1007/s00792-019-01125-4 | 635-647 | Vol: 23 Issue: 6 | 1431-0651 | Thomson Reuters ISI (SCIE) | English | The true-branching cyanobacterium Fischerella thermalis (also known as Mastigocladus laminosus) is widely distributed in hot springs around the world. Morphologically, it has been described as early as 1837. However, its taxonomic placement remains controversial. F. thermalis belongs to the same genus as mesophilic Fischerella species but forms a monophyletic clade of thermophilic Fischerella strains and sequences from hot springs. Their recent divergence from freshwater or soil true-branching species and the ongoing process of specialization inside the thermal gradient make them an interesting evolutionary model to study. F. thermalis is one of the most complex prokaryotes. It forms a cellular network in which the main trichome and branches exchange metabolites and regulators via septal junctions. This species can adapt to a variety of environmental conditions, with its photosynthetic apparatus remaining active in a temperature range from 15 to 58 °C. Together with its nitrogen-fxing ability, this allows it to dominate in hot spring microbial mats and contribute signifcantly to the de novo carbon and nitrogen input. Here, we review the current knowledge on the taxonomy and distribution of F.thermalis, its morphological complexity, and its physiological adaptations to an extreme environment. |
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| TRANSFORMACIÓN: Grandes desafíos - Profundos cambios | Aldunce, P. | 2019 | Agua y Extremos | https://www.cr2.cl/transformacion-grandes-desafios-profundos-cambios/ | cr2.cl | El planeta está experimentando rápidos cambios, a una velocidad sin precedentes. En una sola generación, los humanos nos hemos convertido en una enorme fuerza global, somos parte de esta historia, hemos construido tanto el pasado, como el presente del planeta, somos responsables, pero esta responsabilidad no puede ser un motivo para la inacción, sino más bien un llamado a la acción, con esperanza de escribir un mejor futuro para el planeta. Para enfrentar el futuro, no es suficiente responder con cambios menores o incrementales, los cuales a pesar de que han sido necesarios, no son suficientes. Hay una necesidad, urgencia y oportunidad de explorar más allá, utilizando el enfoque de la Transformación, para realizar cambios a mayor escala y más profundos. Es importante considerar que los enfoques incrementales y los transformacionales son complementarios, no compiten. Los procesos transformacionales siempre han existido, ya que la transformación es un proceso inherente a la sociedad. Por otro lado, la ciencia ha logrado grandes avances en la aproximación de la transformación a lo largo de distintas disciplinas, sin embargo, en muchos casos, los conocimientos científico y práctico han evolucionado independientemente. El presente documento aborda la temática de la transformación, siendo un documento de resumen, que pueda ser de utilidad tanto para investigadores como otros actores sociales, que estén interesados en utilizar la perspectiva de la transformación, como un enfoque válido para responder a las crecientes demandas que emergen para enfrentar el cambio climático. |
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| Comité Científico COP25: Criósfera y Cambio Climático 50 preguntas y respuestas | Aldunce, P.; Andrade, C.; Anicama, J.; Arana, P.; Azócar, G.; Cabrol, L.; Carrasco, J.; Casanova-Katny, A.; Cavieres, L.; Cereceda-Balic, F.; Christie, D.; Cid-Agüero, P.; Cordero, R.; Crespo, S.; Damiani, A.; Dussaillant-Jones, A.; Fernández, A.; Fernández, C.; Fernandoy, F.; Frangopulos, M.; Fuent... | 2019 | Agua y Extremos; Ciudades Resilientes | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-criosfera-y-antartica/12.Criosfera-y-cambio-climatico.pdf | La criósfera comprende las partes de la Tierra donde encontramos agua en estado sólido: nieve, glaciares, hielo marino, mantos de hielo y suelos congelados (permafrost). El territorio chileno posee todos estos componentes, pero de ellos, los más relevantes son los glaciares, con alrededor de 24 000 km2 (3 % del área mundial). Sin embargo, los glaciares están en franco retroceso debido al cambio climático. Su distribución varía con la altitud y latitud, con un gradiente desde los Andes Norte y Centro (4.4 %), a la región centro-sur (6.2 %) hasta alcanzar su mayor extensión en la zona de la Patagonia y Tierra del Fuego (89.3 %). La pérdida de masa de hielo en la cordillera de los Andes ha sido de 23 gigatoneladas en los últimos veinte años. Preocupante aspecto, por ser el recurso agua uno de los que está más amenazado actualmente en la zona centro-norte del país. En el marco del cambio climático, la Antártica presenta procesos antagónicos y sinérgicos. Las aguas muy frías del océano tienen una gran capacidad para exportar carbono desde la atmósfera y ejercer un importante control sobre el clima regional y global. No obstante, el calentamiento global está derritiendo una parte de la cobertura de hielo, lo cual libera el hierro atrapado en su interior y potencia la productividad y exportación de carbono al fondo del océano (que estaba originalmente como CO2 en la atmósfera). Sin embargo, esta capacidad del océano de capturar CO2 se contrapone con el riesgo de incrementar su acidificación. | ||||||||
| Informe de Devolución: Preparados para La Gloria, Incendios Forestales | Aldunce, P.; Pérez, S.; Flores-Haverbeck, F.; Stark, V.; Fuentes, C.; Conte, E.; Marchant, G. | 2019 | https://www.cr2.cl/informe-de-devolucion-la-gloria-preparados-para-la-gloria-incendios-forestales/ | 16 | Spanish | Durante el verano del 2017 la zona centro-sur de nuestro país fue afectada por un devastador megaincendio forestal denominado la ?Tormenta de Fuego? que impactó profundamente la localidad de La Gloria. Luego del incendio forestal, distintas generaciones nos sentamos a hablar, pintar, dibujar, y escribir nuestra historia. Recordamos lugares, experiencias, y costumbres que nos mostraron lo que nos une. Así, transformamos lo que significa este lugar para nosotros. Hoy pensamos al bosque como un lugar de juego y encuentro. Sabemos que hacer en caso de tener que enfrentar un incendio en el futuro, estamos preparados para La Gloria. Lo que construimos juntos Construimos nuestra historia, juntándonos en 5 talleres, donde compartimos vivencias y aprendizajes sobre la experiencia del incendio. Nos sentamos a pensar en conjunto, y generamos soluciones para la comunidad. A lo largo de los talleres nos acompañó la construcción colectiva de un telar, y la creación colectiva de mapas en donde ubicábamos nuestros recuerdos, emociones y cómo nos vemos en el futuro |
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| Comité Científico COP25: Transformación: Un tema emergente en la adaptación al cambio climático en Chile. Informe de la mesa de Adaptación | Aldunce, P.; Vicuña, S. | 2019 | Agua y Extremos | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-adaptacion/5.Transformacion-Un-tema-emergente-en-la-adaptacion-al-cambio-climatico-en-Chile.pdf | La transformación es una de las temáticas que está emergiendo en el ámbito del cambio climático en Chile. Uno de los aspectos más relevantes es promover la alfabetización del enfoque transformacional, con especial énfasis en sus modos de implementación, ya que se reconoce cierta desinformación y confusión respecto de la transformación. En particular en el caso de organizaciones gubernamentales, se recomienda comenzar su inclusión de forma explícita en las discusiones, toma de decisiones e instrumentos de política pública. Se denota una urgencia asociada a la transformación debido a la necesidad de actuar y planificar hoy para: i) hacer frente a los impactos actuales, por ejemplo, aquellos producidos por eventos climáticos extremos; ii) obtener resultados en el futuro, reforzando la visión de largo plazo, como es el caso de la Estrategia de Largo Plazo para un Desarrollo Bajo en Emisiones (ELP) del Acuerdo de París; y iii) anticiparse a los impactos futuros, en especial si se cuenta con proyecciones climáticas, para lograr una mayor probabilidad de transformaciones positivas. | ||||||||
| Comité Científico COP25: Adaptación al cambio climático en Chile: Brechas y recomendaciones. Informe de las mesas Adaptación y Agua. | Aldunce, P.; Vicuña, S. | 2019 | Agua y Extremos | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-adaptacion/1.Adaptacion-Brechas-Aldunce.pdf | El presente informe se estructura en tres secciones. Primero, se presentan las necesidades de implementación de medidas de adaptación en un contexto global y a nivel nacional. Segundo, se hace una revisión crítica de la situación actual del uso de instrumentos públicos para la implementación de la adaptación al cambio climático en Chile. Tercero, en este análisis se entregan algunas brechas relevantes. Por último, se presenta una sección en la que se plantean una serie de desafíos y recomendaciones para mejorar la implementación de la adaptación en Chile. Sus principales mensajes son que existe consenso científico en que el cambio climático es un hecho y que en gran parte ha sido causado por la actividad antrópica. El cambio climático posee múltiples impactos en la actualidad y se espera que aumenten en el futuro. Como segundo mensaje, se concluye que Chile es un país altamente vulnerable al cambio climático. Uno de sus principales impactos es la disminución en la disponibilidad de recursos hídricos producto de la reducción en precipitación, aumento en temperatura y el derretimiento acelerado de la criósfera. Además, existen impactos asociados a otras amenazas de origen climático, como los aluviones, marejadas, incendios y olas de calor, entre otras. El cambio climático afecta de forma diferente a la población, la infraestructura y los sistemas naturales en función de una vulnerabilidad diferenciada. La adaptación emerge como una posibilidad real de aumentar la resiliencia y reducir la vulnerabilidad de estos sistemas. Nuestro país ha avanzado en el diseño e implementación de políticas públicas de adaptación. Sin embargo, existen reales posibilidades de mejoras a lo ya hecho en términos de diseño, implementación y seguimiento de Planes de Adaptación al Cambio Climático (PACC), así como también en la ambición de compromisos de las Contribuciones Determinadas a nivel Nacional (NDC). El mensaje final de este informe se basa en recomendaciones de mejoras en estos temas. | ||||||||
| Elemental and Mineralogical Composition of the Western Andean Snow (18°S–41°S) | Scientific Reports | Alfonso, J.; Cordero, R.; Rowe, P.; Neshyba, S.; Casassa, G.; Carrasco, J.; MacDonell, S.; Lambert, F.; Pizarro, J.; Fernandoy, F.; Feron, S.; Damiani, A.; Llanillo, P.; Sepulveda, E.; Jorquera, J.; Garcia, B.; Carrera, J.; Oyola, P.; Kang, C. | 2019 | Ciudades Resilientes | 10.1038/s41598-019-44516-5 | http://www.nature.com/articles/s41598-019-44516-5 | 8130 | Vol: 9 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The snowpack is an important source of water for many Andean communities. Because of its importance, elemental and mineralogical composition analysis of the Andean snow is a worthwhile effort. In this study, we conducted a chemical composition analysis (major and trace elements, mineralogy, and chemical enrichment) of surface snow sampled at 21 sites across a transect of about 2,500 km in the Chilean Andes (18–41°S). Our results enabled us to identify five depositional environments: (i) sites 1–3 (in the Atacama Desert, 18–26°S) with relatively high concentrations of metals, high abundance of quartz and low presence of arsenates, (ii) sites 4–8 (in northern Chile, 29–32°S) with relatively high abundance of quartz and low presence of metals and arsenates, (iii) sites 9–12 (in central Chile, 33–35°S) with anthropogenic enrichment of metals, relatively high values of quartz and low abundance of arsenates, (iv) sites 13–14 (also in central Chile, 35–37°S) with relatively high values of quartz and low presence of metals and arsenates, and v) sites 15–21 (in southern Chile, 37–41°S) with relatively high abundance of arsenates and low presence of metals and quartz. We found significant anthropogenic enrichment at sites close to Santiago (a major city of 6 million inhabitants) and in the Atacama Desert (that hosts several major copper mines). |
| Dietary diverstiy in the Atacama desert during the Late intermediate period of northern Chile | Quaternary Science Reviews | Alfonso-Durruty, M.; Gayo, E.; Standen, V.; Castro, V.; Latorre, C.; Santoro, C.; Valenzuela, D. | 2019 | Ciudades Resilientes | 10.1016/j.quascirev.2019.04.022 | https://linkinghub.elsevier.com/retrieve/pii/S0277379119300356 | 54-67 | Vol: 214 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | The Pacific Ocean that flanks the hyperarid Atacama Desert of Northern Chile is one of the richest biomass producers around the world. Thus, it is considered a key factor for the subsistence of prehistoric societies (including mixed-economy groups), that inhabited its coastal ecosystems as well as the neighboring inland areas. This study assesses the Arica Culture groups' diet (Late Intermediate Period; 1000–1530 CE), through stable isotope (on bone-collagen; δ 13 C and δ 15 N)and dental pathology data. Seventy-seven (n = 77)individuals from two inland (LLU54 and AZ8)and one coastal (CAM8)archaeological sites were studied. Results show an important, but lower than predicted by earlier studies, contribution of marine resources in the diet of all three groups. Dental pathologies and stable isotopes indicate that these groups' diet varied in correlation with their distance to the Pacific Ocean as well as group and individual preferences. The results challenge the idea that Arica Culture groups depended heavily on marine resources for their subsistence. In contrast, this study shows both that the Arica Culture groups’ diet was diverse, and that the terrestrial resources consumed were mostly contributed by C 3 /CAM plants instead of maize. | |
| Spatial congruence among indicators of recovery completeness in a Mediterranean forest landscape: Implications for planning large-scale restoration | Ecological Indicators | Altamirano, A.; Miranda, A.; Meli, P.; Dehennin, J.; Muys, B.; Prado, M.; Catalán, G.; Smith-Ramírez, C.; Bustamante-Sánchez, M.; Lisón, F.; María Rey-Benayas, J. | 2019 | Cambio de Uso de Suelo | 10.1016/j.ecolind.2019.03.046 | https://linkinghub.elsevier.com/retrieve/pii/S1470160X19302274 | 752-759 | Vol: 102 | 1470-160X | Thomson Reuters ISI (SCIE) | English | Natural regeneration has been proposed as a cost-effective forest restoration approach for both small and largescale initiatives. However, attributes for assessing the success of forest restoration through natural regeneration may vary among them in spatial patterns depending on the scale of analysis and on environmental gradients. Here we analysed the spatial patterns of recovery completeness (i.e. how similar attributes in restored forests are to the same attributes in reference forests) in response to environmental factors in a Mediterranean forest landscape of Central Chile. We evaluated (1) forest recovery completeness using basal area (BA), quadratic mean diameter (QMD), adult species density (ASD), adult species richness (ASR), and seedling species richness (SSR); (2) the spatial congruence of recovery completeness estimated by each of these indicators; and (3) the environmental factors potentially shaping these spatial patterns. We used field measurements and geospatial information sources to quantify and predict indicator responses by fitting boosted regression tree models. To assess the spatial congruence of predictions we overlaid high-level recovery completeness values for all indicators. Overall recovery completeness in the study area was 72.7%, suggesting positive prospects for attaining fully restored forests. Recovery completeness had a resulted higher for diversity (92.3%−99.6%) than structural forest attributes (33.5%−76.9%); however, spatial congruence among recovery indicators was low due to the uneven spatial responses of each indicator. The maximum potential spatial congruence was<10%, and was predicted only by two environmental variables (soil bulk density and slope). Our results suggest that low spatial congruence among forest recovery indicators may hinder the monitoring of restoration at large scales. The implications of such divergence in defining restoration success can be enormous given the current global challenge of forest restoration. Although our research was tested in a threatened region of global importance, our results may have wider significance for restoration planning providing cautionary notes and recommendations for the appropriate use of forest recovery indicators when monitoring large-scale restoration projects. | |
| The Impacts of Native Forests and Forest Plantation on Water Supply in Chile | Forests | Alvarez-Garreton, C.; Lara, A.; Boisier, J.; Galleguillos, M. | 2019 | Agua y Extremos; Cambio de Uso de Suelo | 10.3390/f10060473 | https://www.mdpi.com/1999-4907/10/6/473 | 473 | Vol: 10 Issue: 6 | 1999-4907 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Over the past 40 years, south-central Chile has experienced important land-use-induced land cover changes, with massive conversion from native forests (NF) to Pinus radiata D.Don and Eucalyptus spp. exotic forest plantations (FP). Several case studies have related this conversion to a reduction in water supply within small catchments (<100 ha). In this work, we explore the impacts of NF and FP on streamflow by using a large-sample catchment dataset recently developed for Chile. We select 25 large forested catchments (>20,000 ha) in south-central Chile (35° S–41° S), analyze their land cover and precipitation spatial distributions, and fit a regression model to quantify the influence of NF, FP, grassland (GRA) and shrubland (SHR) partitions on annual runoff. To assess potential effects of land cover changes on water supply, we use the fitted model (R2 = 0.84) in synthetic experiments where NF, GRA and SHR covers within the catchments are replaced by patches of FP. We show that annual runoff consistently decreases with increments of FP, although the magnitude of the change (ranging from 2.2% to 7.2% mean annual runoff decrease for 10,000 ha increment in FP) depends on several factors, including the initial land cover partition within the basin, the replaced land cover class, the area of the catchment, and the type of catchment (drier or humid). Finally, in the context of the mitigation strategies pledged in the Chilean NDC (Nationally Determined Contributions defined after the Paris Agreement), which include the afforestation of 100,000 ha (mainly native forest) by 2030, we quantify the impacts on water supply due to the afforestation of 100,000 ha with different combinations of NF and FP. We show that annual runoff is highly sensitive to the relative area of FP to NF: ratios of FP to NF areas of 10%, 50% and 90% would lead to 3%, −18% and −40% changes in mean annual runoff, respectively. Our results can be used in the discussion of public policies and decision-making involving forests and land cover changes, as they provide scientifically-based tools to quantify expected impacts on water resources. In particular, this knowledge is relevant for decision making regarding mitigation strategies pledged in the Chilean NDC. |
| Does energy poverty have a female face in Chile? | Tapuya: Latin American Science, Technology and Society | Amigo-Jorquera, C.; Guerrero-González, M.; Sannazzaro, J.; Urquiza-Gómez, A. | 2019 | Ciudades Resilientes | 10.1080/25729861.2019.1608038 | https://www.tandfonline.com/doi/full/10.1080/25729861.2019.1608038 | 1-13 | Vol: 2 | 2572-9861 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | The relationship between gender inequalities (GI) and energy poverty (EP) has not been discussed as a whole in worldwide recent debates, although feminist analyses have demonstrated that GI have had an impact on the everyday life of women, men, and their dependents. This research paper addresses the relationship between GI and EP through an analysis of relevant secondary sources on poverty and people’s use of time, in order to understand how GI affect women’s access to energy in Latin America, particularly in Chile. Moreover, it seems that there are reasons to believe that EP has a female face. Therefore, this study looks into strategic policies for ensuring safe and affordable energy for women. Likewise, this research paper presents how these efforts would contribute to deal with some other key issues, such as energy transition and a sustainable development process. To sum up, this investigation identifies the possible benefits that improving energy access would bring to women, as well as how those improvements would consistently help to meet the goals established by international treaties that aim to seek equality for women through ending poverty and by giving them access to energy. |
| Inter-annual variability of oceanographic conditions and phytoplankton in Valparaíso Bay (~33°S), central Chile | Revista de Biología Marina y Oceanografía | Aparicio-Rizzo, P.; Masotti, I. | 2019 | Zonas Costeras | 10.22370/rbmo.2019.54.1.1495 | https://revistas.uv.cl/index.php/rbmo/article/view/1495 | 70 | Vol: 54 Issue: 1 | 0717-3326 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The inter-annual variability of oceanographic conditions and phytoplankton abundance and biomass was studied using 10 years (1986-1996) of in situ observations at a fixed station in Valparaíso Bay (~33ºS). The time series analysis revealed that strong S-SW winds drive a quasi-permanent upwelling activity that maintain the nutrients availability in the water column to fuel the phytoplankton in the bay. The most important changes in bio-oceanographic conditions were observed during 1987 El Niño event, which was characterized by higher temperatures but lower values for salinity, nitrate, and phosphate concentrations, together with a decrease of phytoplankton biomass compared to 1988 La Niña event when colder, saltier, and nutrient-rich upwelled water were observed. High Aconcagua River discharges were observed during the El Niño conditions (1987-1988 and 1993), which led to a decrease in surface salinity and a high abundance of dinoflagellates. Two periods with differences in bio-oceanographic conditions were observed; 1988-1992 showed lower temperatures but higher nutrients (nitrate), phytoplankton biomass and abundance of diatoms than 1993-1996 period. Throughout the study period, positive trends in upwelling activity was registered accompanied by a fall in phytoplankton biomass and dinoflagellate abundance. This paper provides new evidences concerning the influence of El Niño Southern Oscillation (ENSO) in phytoplankton and oceanographic conditions in the coastal upwelling off central Chile. |
| A new method to evaluate the vulnerability of watersheds facing several stressors: A case study in mediterranean Chile | Science of The Total Environment | Arriagada, L.; Rojas, O.; Arumí, J.; Munizaga, J.; Rojas, C.; Farías, L.; Vega, C. | 2019 | Zonas Costeras | 10.1016/j.scitotenv.2018.09.237 | https://linkinghub.elsevier.com/retrieve/pii/S0048969718336817 | 1517-1533 | Vol: 651 | 0048-9697 | Thomson Reuters ISI (SCIE) | English | Freshwater systems are subjected to multiple anthropogenic stressors and natural disturbances that act as debilitating agents and modifiers of river systems, causing cumulative and synergistic effects that deteriorate their health and result in watershed vulnerability. This study proposes an easy-to-apply spatial method of watershed vulnerability evaluation using Geographic Information Systems (GIS) in the Andalién River watershed, located in the Chilean mediterranean. A watershed vulnerability index (WVI) based on three sub-indices – anthropogenic stressors, environmental fragility and natural disturbances – was developed. To determine the index grouping weights, expert surveys were carried out using the Delphi method. We subsequently normalized and integrated the factors of each sub-index with relative weights. The ranges of each thematic layer were re-classified to establish vulnerability scores. The watershed was divided into three sections: headwaters zone, transfer zone and depositional zone. The watershed vulnerability index showed that 41% of the watershed had very low vulnerability and 42% had medium vulnerability, while only 1% – in the depositional zone – had high vulnerability. A one-way ANOVA was carried out to analyze the vulnerability differences among the three sections of the watershed; it showed significant differences (F (2, 16) = 8.15: p < 0.05). The a posteriori test showed differences between the headwaters and depositional zones (Tukey test, p = 0.005) and between the transfer and depositional zones (Tukey test, p = 0.014). To validate the WVI, water quality was measured at 16 stations in the watershed; there was a significant correlation between vulnerability level and NO2 − levels (r = 0.8; p = 0.87; α = 0.05) and pH (r = 0.8; p = 0.80; α = 0.05). The WVI showed the cumulative effects of multiple stressors in the depositional zone of the watershed. This is the first study to evaluate and validate non-regulated watershed vulnerability with GIS using multiple anthropogenic and natural stressors. | |
| A Harmonized Nitrous Oxide (N2O) Ocean Observation Network for the 21st Century | Frontiers in Marine Science | Bange, H.; Arévalo-Martínez, D.; de la Paz, M.; Farías, L.; Kaiser, J.; Kock, A.; Law, C.; Rees, A.; Rehder, G.; Tortell, P.; Upstill-Goddard, R.; Wilson, S. | 2019 | Zonas Costeras | 10.3389/fmars.2019.00157 | https://www.frontiersin.org/article/10.3389/fmars.2019.00157/full | 157 | Vol: 6 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Nitrous oxide (N2O) is an important atmospheric trace gas involved in tropospheric warming and stratospheric ozone depletion. Estimates of the global ocean contribution to N2O emissions average 21% (range: 10 to 53%). Ongoing environmental changes such as warming, deoxygenation and acidification are affecting oceanic N2O cycling and emissions to the atmosphere. International activities over the last decades aimed at improving estimates of global N2O emissions, including (i) the MarinE MethanE and NiTrous Oxide database (MEMENTO) for archiving of quality-controlled data, and (ii) a recent large-scale inter-laboratory comparison by Working Group 143 of the Scientific Committee on Ocean Research (SCOR). To reduce uncertainties in oceanic N2O emission estimates and to characterize the spatial and temporal variability in N2O distributions in a changing ocean, we propose the establishment of a harmonized N2O Observation Network (N2O-ON) combining discrete and continuous data from various platforms. The network will integrate observations obtained by calibrated techniques, using time series measurements at fixed stations and repeated hydrographic sections on voluntary observing ships and research vessels. In addition to exploiting existing oceanographic infrastructure, we propose the establishment of central calibration facilities in selected international laboratories to improve accuracy, and ensure standardization and comparability of N2O measurements. Final data products will include a harmonized global N2O concentration and emission fields for use in model validation and projections of future oceanic N2O emissions, to inform the global research community and policy makers. |
| Anthropocene and streamflow: Long-term perspective of streamflow variability and water rights | Elementa: Science of the Anthropocene | Barria, P.; Rojas, M.; Moraga, P.; Muñoz, A.; Bozkurt, D.; Alvarez, C. | 2019 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.1525/elementa.340 | https://www.elementascience.org/article/10.1525/elementa.340/ | 2 | Vol: 7 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Since 1981, water allocation in Chile has been based on a water use rights (WURs) market, with limited regulatory and supervisory mechanisms. The volume to be granted as permanent and eventual WURs is calculated from streamflow records, if stream gauge data are available, or from hydrologic parameter transfer from gauged to ungauged catchments, usually with less than 50 years of record. To test the per- formance of this allocation system, while analyzing the long-term natural variability in water resources, we investigated a 400 year-long (1590–2015) tree-ring reconstruction of runoff and historical water rights for Perquilauquén at Quella catchment, a tributary to the Maule River in Central Chile (35°S–36°30S). Furthermore, we assess how the current legislation would perform under a projected climate scenario, based on historical climate simulations of runoff calibrated against observed data, and future projections. Our analyses indicate that the allocation methodology currently applied by the Water Authority in Chile is very sensitive to the time window of data used, which leads to an underestimation of variability and long-term trends. According to the WURs database provided by the Chilean Water Directorate, WURs at Perquilauquén at Quella are already over-allocated. Considering regional climate projections, this condition will be exacerbated in the future. Furthermore, serious problems regarding the access and quality of infor- mation on already-granted WURs and actual water usage have been diagnosed, which further encumber environmental strategies to deal with and adapt to climate change. We emphasize the urgent need for a review and revision of current water allocation methodologies and water law in Chile, which are not concordant with the dynamics and non-stationarity of hydrological processes. Water scarcity and water governance are two of the key issues to be faced by Chile in the Anthropocene. |
| The Anthropocene in Chile | Environmental Humanities | Bauer, C.; Correa, C.; Gallardo, L.; González, G.; Guridi, R.; Latorre, C.; Navarrete, S.; Pommier, E.; Riffo, S.; Saavedra, B.; Simonetti, C.; Tironi, M. | 2019 | Ciudades Resilientes | 10.1215/22011919-7754578 | https://read.dukeupress.edu/environmental-humanities/article/11/2/467/140786/The-Anthropocene-in-ChileToward-a-New-Pact-of | 467-476 | Vol: 11 Issue: 2 | 2201-1919, 2201-1919 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | English | We, academics, thinkers, activists and professionals, Chileans and foreigners, from the broad spectrum of natural and social sciences, the humanities, the arts and the spiritual world, make a call to rethink from its basis the way in which we inhabit “the human” and its place in the history of the Earth. Our call emerges in response to the Anthropocene, a notion proposed recently by the Subcommittee on Stratigraphy of the International Quaternary Union of Geological Sciences to refer to a geological epoch that would follow the Holocene. As its name reflects, the Anthropocene would be defined by the irreversible changes in the biophysical and geological conditions, at a planetary scale, as a consequence of human actions. In contrast to climate change, the notion of the Anthropocene refers to human influence at a planetary scale. That is, the Anthropocene signals a process that involves the Earth system as a whole and not only some of its components. Similarly, the Anthropocene refers to a process over a significant timescale in the history of Earth and, therefore, beyond specific ecosystemic transformations. Lastly, the Anthropocene indicates the potential extinction of the conditions of the biosphere that enable human life on Earth. Since the changes in the conditions of the biosphere are the result of colonialism, capitalism, and a consumption-oriented society, the Anthropocene has generated an intense debate not only in the field of earth sciences but also in the social sciences, humanities, and the arts. This debate has revolved around the need to rethink the relationship between nature and society; the cohabitation between human and biophysical processes; and the types of knowledge that are required to understand and confront planetary changes. As a concept, however, the Anthropocene risks falling into the anthropocentrism and biocentrism that is precisely at stake. Taking seriously the challenge of the Anthropocene and the need to generate a pact that would be genuinely radical, this manifesto views the Anthropocene as a space to debate and not as a closed scientific category to be accepted. The Anthropocene, as those who sign this manifesto attest, is a call to invent new possible futures. |
| The Role of Streamside Native Forests on Dissolved Organic Matter in Forested and Agricultural Watersheds in Northwestern Patagonia | Forests | Becerra-Rodas, C.; Little, C.; Lara, A.; Sandoval, J.; Osorio, S.; Nimptsch, J. | 2019 | Agua y Extremos; Cambio de Uso de Suelo | 10.3390/f10070595 | https://www.mdpi.com/1999-4907/10/7/595 | 595 | Vol: 10 Issue: 7 | 1999-4907 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Streamside native forests are known for their key role in water provision, commonly referred to as buffers that control the input or output of nutrients from terrestrial to aquatic ecosystems (i.e., nitrogen or carbon cycle). In order to assess the functional role of indigenous forests along streamside channels, we measured 10 parameters associated with DOM (Dissolved Organic Matter) at 42 points in 12 small catchments (15–200 ha) dominated by native forests (reference, WNF), forest plantations (WFP) and agricultural lands (WAL) in which the land cover portion was calculated in the entire watershed and along 30 and 60-m wide buffer strips. We found that watersheds WFP and WAL were statistically different than WNF, according to DIC concentrations (Dissolved Inorganic Carbon) and the intensity of the maximum fluorescence of DOM components. Using linear models, we related streamside native forest coverage in buffer strips with DOM parameters. The increase of streamside native forest coverage in 60 m wide buffer strips (0–100%) was related to lower DIC concentrations (0.89 to 0.28 mg C L−1). In watersheds WFP and WAL, the humic and fulvic-like components (0.42 to 1.42 R.U./mg C L−1) that predominated were related to an increase in streamside native forest coverage in the form of a 60 m wide buffer strip (0–75%). This is evidence that streamside native forests influence outputs of detritus and lowered in-stream processing with concomitant downstream transport, and functional integrity and water quality. We propose that DOM quantity and quality may be a potential tool for the identification of priority areas near streams for conservation and ecological restoration in terms of recovery of water quality as an important ecosystem service. The results of this study are useful to inform policy and regulations about the width of streamside native forests as well as their characteristics and restrictions. |
| A statistical physics approach to perform fast highly-resolved air quality simulations – A new step towards the meta-modelling of chemistry transport models | Environmental Modelling & Software | Bessagnet, B.; Couvidat, F.; Lemaire, V. | 2019 | Ciudades Resilientes | 10.1016/j.envsoft.2019.02.017 | https://linkinghub.elsevier.com/retrieve/pii/S136481521830896X | 100-109 | Vol: 116 | 13648152 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | A methodology rested on model-based machine learning using simple linear regressions and the parameterizations of the main physics and chemistry processes has been developed to perform highly-resolved air quality simulations. The training of the methodology is (i) completed over a 6-month period using the outputs of the chemical transport model CHIMERE, and (ii) then applied over the subsequent 6 months. Despite rough assumptions, this new methodology performs as well as the raw CHIMERE simulation for daily mean concentrations of the main criteria air pollutants (NO2, Ozone, PM10 and PM2.5) with correlations ranging from 0.75 to 0.83 for the particulate matter and up to 0.86 for the maximum ozone concentrations. Some improvements are investigated to expand this methodology to several other uses, but at this stage the method can be used for air quality forecasting, analysis of pollution episodes and mapping. This study also confirms that including a minimum set of selected physical parameterizations brings a high added value on machine learning processes. |
| What is the ‘Social’ in Climate Change Research? A Case Study on Scientific Representations from Chile | Minerva | Billi, M.; Blanco, G.; Urquiza, A. | 2019 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1007/s11024-019-09369-2 | http://link.springer.com/10.1007/s11024-019-09369-2 | 293-315 | Vol: 57 Issue: 3 | 0026-4695 | Thomson Reuters ISI (SSCI) | All Open Access; Hybrid Gold Open Access | English | Over the last few decades climate change has been gaining importance in international scientifc and political debates. However, the social sciences, especially in Latin America, have only lately become interested in the subject and their approach is still vague. Scientifc understanding of global environmental change and the process of designing public policies to face them are characterized by their complexity as well as by epistemic and normative uncertainties. This makes it necessary to problematize the way in which research eforts understand ‘the social’ of climate change. How do ‘the climate’ and ‘the social’ interpenetrate as scientifc objects? What does the resulting feld look like? Is the combination capable of promoting refexivity and collaboration on the issue, or does it merely become dispersed with difuse boundaries? Our paper seeks to answer these and other related questions using Chile as a case study and examining peer-reviewed scientifc research on the topic. By combining in-depth qualitative content analysis of each paper with a statistical meta-analysis, we were able to: characterize the key content and forms of such literature; identify divisions and patterns within it; and, discuss some factors and trends that may help explain these. We conclude that the literature displays two competing trends: while it is inclined to become fragmented beyond the scope of the ‘mitigation’ black box, it also tends to cluster along the lines of methodological distinctions traditionally contested within the social sciences. This, in turn, highlights the persistence of disciplinary divisions within an allegedly interdisciplinary feld. |
| On crises, ecologies, and transitions: reflections on latin american social theory regarding global environmental change | Revista Colombiana de Sociología | Blanco Wells, G.; Gunther, M. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.15446/rcs.v42n1.73190 | https://revistas.unal.edu.co/index.php/recs/article/view/73190 | 19-40 | Vol: 42 Issue: 1 | 0120-159X | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | Spanish | On the basis of the review of the main traditions of environmental thought that have been influential in Latin America since the 1970s, the article describes the relationships established between the notions of crisis and global environmental change. To this effect, it examines the distinctive features of the representation of the environmental field in the academic production of regional social scientists, the ethical constructions grounding that production, and the links established among ecology, crisis, and development. The text provides an overview of both the Latin American production and the adaptations and interpretations of other ideas that did not originate in Latin America but that have been influential in the region. Methodologically, it carries out a double hermeneutic analysis of the relevant bibliography, mainly of the texts and authors that inspired and laid the bases for the perspectives studied here. The first section conducts an analysis and description of the notions of crisis and the ethical responses to nature that serve as the basis for theoretical proposals. The second section provides an overview of the construction of environmental issues on the basis of five theoretical perspectives: environmental and ecological economics; ecological Marxism; ecological modernization; political ecology; political ontology and the decolonial perspective. Finally, the paper includes a series of conclusions and reflections on the political and practical scope of theoretical production on environmental issues in Latin America. We argue that, given the socio-material realities in which its evidence is grounded, Latin American social thinking on global environmental change is in a privileged position to contribute to the construction of other practices that do not focus on instrumental appropriation, as well as to making visible other relational ontologies between human beings and non-human nature. |
| The social life of energy: notes for the territorialized study of energy transitions | Sociologias | Blanco-Wells, G. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.1590/15174522-0215106 | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-45222019000200160&tlng=es | 160-185 | Vol: 21 Issue: 51 | 1807-0337, 1517-4522 | SciELO | All Open Access; Gold Open Access | Spanish | Resumen Se presenta una propuesta teórica y metodológica para el estudio sociológico de la transición energética hacia energías renovables no convencionales, entendida como un proceso de cambio inducido vinculado a cambio climático, cuyos cursos de acción no están exentos de controversias sociotécnicas. La investigación se fundamenta en cuatro años de investigación sobre trayectorias territoriales de producción, uso y significación de la energía en tres regiones del sur-austral de Chile. A partir de una matriz teórica de la transición energética basada en los grados de renovabilidad y convencionalidad de la energía, se identifican diferentes regímenes sociotécnicos a partir de los cuales se debe indagar de modo empírico las formas situadas que adopta esta transición. Cada uno de estos regímenes fue investigado a través de casos de estudio lo que nos permite presentar aprendizajes generales de interés sociológico. A modo de conclusión, se propone ir más allá del concepto de régimen a través de la noción de ensamblaje, lo que permite explorar modos no lineales en que se asocian agentes heterogéneos en la territorialización de la energía. Además, se plantea que los grados de aceptación o rechazo social de la energía no debe ser el motor que mueva la investigación sobre esta materia, sino la forma en que las sociedades definen, debaten y construyen pragmáticamente formas democráticas y justas de uso energético en cada territorio. Desde nuestra perspectiva, esto supone avanzar en comprender estos procesos como parte de las soberanías energéticas de los pueblos. , Abstract This paper presents a theoretical and methodological proposal for the sociological study of energy transition towards non-conventional renewable energy, as a process of induced transformation related to climate change, whose courses of action are not exempt from socio-technical controversies. The proposal is based on a four-year research program on territorial trajectories of production, use and making sense of energy in three regions of southern Chile. Based on a theoretical matrix of energy transition structured according the degrees of renewability and conventionality of energy, different socio-technical regimes are identified, from which the situated forms taken by this transition should be empirically investigated. Each of these regimes was researched through case studies, which allows us to present some general lessons of sociological interest. Concluding, it is proposed to transcend the concept of regime by means of the notion of assemblage, which allows for exploring non-linear ways heterogeneous agents associate in the territorialization of energy. In addition, we contend that the driving force behind research on this subject should not be the degrees of social acceptance or rejection of different sources of energy, but rather the way societies define, debate and pragmatically construct democratic and fair forms of energy use in a given territory. From our perspective, this means advancing in the understanding of these processes as part of people’s energy sovereignty. |
| Human–environmental drivers and impacts of the globally extreme 2017 Chilean fires | Ambio | Bowman, D.; Moreira-Muñoz, A.; Kolden, C.; Chávez, R.; Muñoz, A.; Salinas, F.; González-Reyes, Á.; Rocco, R.; de la Barrera, F.; Williamson, G.; Borchers, N.; Cifuentes, L.; Abatzoglou, J.; Johnston, F. | 2019 | Agua y Extremos | 10.1007/s13280-018-1084-1 | http://link.springer.com/10.1007/s13280-018-1084-1 | 350–362 | Vol: 48 | 0044-7447 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | In January 2017, hundreds of fires in Mediterranean Chile burnt more than 5000 km2, an area nearly 14 times the 40-year mean. We contextualize these fires in terms of estimates of global fire intensity using MODIS satellite record, and provide an overview of the climatic factors and recent changes in land use that led to the active fire season and estimate the impact of fire emissions to human health. The primary fire activity in late January coincided with extreme fire weather conditions including all-time (1979–2017) daily records for the Fire Weather Index (FWI) and maximum temperature, producing some of the most energetically intense fire events on Earth in the last 15-years. Fire activity was further enabled by a warm moist growing season in 2016 that interrupted an intense drought that started in 2010. The land cover in this region had been extensively modified, with less than 20% of the original native vegetation remaining, and extensive plantations of highly flammable exotic Pinus and Eucalyptus species established since the 1970s. These plantations were disproportionally burnt (44% of the burned area) in 2017, and associated with the highest fire severities, as part of an increasing trend of fire extent in plantations over the past three decades. Smoke from the fires exposed over 9.5 million people to increased concentrations of particulate air pollution, causing an estimated 76 premature deaths and 209 additional admissions to hospital for respiratory and cardiovascular conditions. This study highlights that Mediterranean biogeographic regions with expansive Pinus and Eucalyptus plantations and associated rural depopulation are vulnerable to intense wildfires with wide ranging social, economic, and environmental impacts, which are likely to become more frequent due to longer and more extreme wildfire seasons. |
| Role of the East Asian trough on the eastern Mediterranean temperature variability in early spring and the extreme case of 2004 warm spell | Climate Dynamics | Bozkurt, D.; Ezber, Y.; Sen, O. | 2019 | Zonas Costeras | 10.1007/s00382-019-04847-5 | http://link.springer.com/10.1007/s00382-019-04847-5 | 2309-2326 | Vol: 53 Issue: 3-4 | 0930-7575 | Thomson Reuters ISI (SCIE) | English | This study investigates the potential influence of the East Asian trough (EAT) on the eastern Mediterranean temperature variability in early spring. In connection with this, it also examines the extreme case of the year 2004 when anomalous warming of the eastern Anatolia resulted in unprecedented snowmelt runoff amounts in the Euphrates and Tigris basins in early March. In the analyses, we used reanalysis data, gridded products of surface temperature and snow cover, river discharge data and satellite imagery. We employed an intensity index for the EAT and a trough displacement index for the Mediterranean trough (MedT) to explore the relationship between the strength of the EAT and the displacement of the MedT at pentad resolution. Our analysis shows that there are statistically significant correlations (at 99% confidence level) between the strength of the EAT and the zonal shift of the MedT on some pentads (e.g., 3rd, 13th, 37th and 59th), but that the highest correlation occurs on the 13th pentad of the year corresponding to the early days of March. It seems that, on this pentad, when the EAT is strong, the MedT tends to be located in the west of its climatological position (about 30−35E ) which causes warmer conditions over the eastern Mediterranean. In 2004, which appears to be an extreme year for this phenomenon, the MedT is positioned and deepened in the central Mediterranean (about 10−15E), and extended towards central Africa during the early days of March. This synoptic pattern provided favorable conditions for the development of a tropical plume/atmospheric river with a southwest-northeast orientation, carrying warm tropical African air towards the eastern Mediterranean and Anatolian highlands resulting in rapid melting of the snowpack as well as severe precipitation, and thus flooding events, in the eastern Anatolia. A key finding in our analysis is that the strengthening of the EAT was instrumental to the increased amplitude of the ridge-trough system over the Euro-Mediterranean region in the early days of 2004 spring. We highlight that the response of surface and upper level meteorological conditions to the amplitude of the ridge-trough system enhanced by the strength of the EAT might be crucial in the understanding of some of the extreme hydrometeorological events in the eastern Mediterranean region. | |
| Dynamical downscaling over the complex terrain of southwest South America: present climate conditions and added value analysis | Climate Dynamics | Bozkurt, D.; Rojas, M.; Boisier, J.; Rondanelli, R.; Garreaud, R.; Gallardo, L. | 2019 | Agua y Extremos; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | 10.1007/s00382-019-04959-y | http://link.springer.com/10.1007/s00382-019-04959-y | 6745-6767 | Vol: 53 Issue: 11 | 0930-7575 | Thomson Reuters ISI (SCIE) | English | This study evaluates hindcast simulations performed with a regional climate model (RCM, RegCM4) driven by reanalysis data (ERA-Interim) over the Pacific coast and Andes Cordillera of extratropical South America. A nested domain configuration at \(0.44^{\circ }\) ( \(\sim\) 50 km) and \(0.09^{\circ }\) ( \(\sim\) 10 km) spatial resolutions is used for the simulations. RegCM4 is also driven by a global climate model (GCM, MPI-ESM-MR) on the same domain configuration to asses the added values for temperature and precipitation (historical simulations). Overall, both 10 km hindcast and historical simulation results are promising and exhibit a better representation of near-surface air temperature and precipitation variability compared to the 50 km simulations. High-resolution simulations suppress an overestimation of precipitation over the Andes Cordillera of northern Chile found with the 50 km simulations. The simulated daily temperature and precipitation extreme indices from 10 km hindcast simulation show a closer estimation of the observed fields. A persistent warm bias ( \(\sim +\,{4\,}^{\circ }\hbox {C}\) ) over the Atacama Desert in 10 km hindcast simulation reveals the complexity in representing land surface and radiative processes over the desert. Difficulties in capturing the temperature trend in northern Chile are notable for both hindcast simulations. Both resolutions exhibit added values for temperature and precipitation over large parts of Chile, in particular, the 10 km resolves the coastal-valley Andes transitions over central Chile. Our results highlight that resolutions coarser than 50 km (e.g., GCMs and reanalysis) miss important climate gradients imposed by complex topography. Given that the highest spatial resolution of the current regional simulations over the South America is about 50 km, higher resolutions are important to improve our understanding of the dynamical processes that determine climate over complex terrain and extreme environments. | |
| Informe de Síntesis Simulaciones climáticas regionales para el continente Antártico | Bozkurt, D.; Rondanelli, R.; Carrasco, J.; Boisier, J.; Morales, B.; Muñoz, F.; Valdebenito, N.; Del Hoyo, M.; Troncoso, M.; Bustos, S. | 2019 | Agua y Extremos; Zonas Costeras | https://cambioclimatico.mma.gob.cl/wp-content/uploads/2020/05/Informe-sintesis-simulacionesantartica.pdf | |||||||||
| Informe de Síntesis Simulaciones climáticas regionales para el territorio insular Chileno | Bozkurt, D.; Rondanelli, R.; Carrasco, J.; Boisier, J.; Morales, B.; Muñoz, F.; Valdebenito, N.; Del Hoyo, M.; Troncoso, M.; Bustos, S. | 2019 | Agua y Extremos; Zonas Costeras | https://cambioclimatico.mma.gob.cl/wp-content/uploads/2020/05/Informe-sintesis-simulaciones-territorio-insular.pdf | |||||||||
| Assessing Snow Accumulation Patterns and Changes on the Patagonian Icefields | Frontiers in Environmental Science | Bravo, C.; Bozkurt, D.; Gonzalez-Reyes, Á.; Quincey, D.; Ross, A.; Farías-Barahona, D.; Rojas, M. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.3389/fenvs.2019.00030 | https://www.frontiersin.org/article/10.3389/fenvs.2019.00030/full | 30 | Vol: 7 | 2296-665X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Recent evidence shows that most Patagonian glaciers are receding rapidly. Due to the lack of in situ long-term meteorological observations, the understanding of how glaciers are responding to changes in climate over this region is extremely limited, and uncertainties exist in the glacier surface mass balance model parameterizations. This precludes a robust assessment of glacier response to current and projected climate change. An issue of central concern is the accurate estimation of precipitation phase. In this work, we have assessed spatial and temporal patterns in snow accumulation in both the North Patagonia Icefield (NPI) and South Patagonia Icefield (SPI). We used a regional climate model, RegCM4.6 and four Phase Partitioning Methods (PPM) in addition to short-term snow accumulation observations using ultrasonic depth gauges (UDG). Snow accumulation shows that rates are higher on the west side relative to the east side for both icefields. The values depend on the PPM used and reach a mean difference of 1,500 mm w.e., with some areas reaching differences higher than 3,500 mm w.e. These differences could lead to divergent mass balance estimations depending on the scheme used to define the snow accumulation. Good agreement is found in comparing UDG observations with modeled data on the plateau area of the SPI during a short time period; however, there are important differences between rates of snow accumulation determined in this work and previous estimations using ice core data at annual scale. Significant positive trends are mainly present in the autumn season on the west side of the SPI, while on the east side, significant negative trends in autumn were observed. Overall, for the rest of the area and during other seasons, no significant changes can be determined. In addition, glaciers with positive and stable elevation and frontal changes determined by previous works are related to areas where snow accumulation has increased during the period 2000–2015. This suggests that increases in snow accumulation are attenuating the response of some Patagonian glaciers to warming in a regional context of overall glacier retreat. |
| Colored raschel mesh effect on growth of Eucalyptus globulus, Eucalyptus nitens and pinus radiata seedlings under nursery conditions; [Efecto de mallas raschel de colores en el crecimiento de plántulas de Eucalyptus globulus, Eucalyptus nitens y pinus radiata en condiciones de vivero] | Bosque | Bustos-Salazar, A.; Zuñiga-Feest, A. | 2019 | Cambio de Uso de Suelo | 10.4067/S0717-92002019000300287 | https://doi.org/10.4067/S0717-92002019000300287 | 287-298 | Vol: 40 Issue: 3 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | Spanish | Forest plantations in Chile represent 2.5 million hectares, with Eucalyptus spp. and Pinus as the most commonly used species. Worldwide, raschel meshes have been used in fruit, horticultural and ornamental shrubs to improve the production of fruits, leaves and flowers. In Chile, it has been operationally used for nursery protocols; they include raschel color mesh to increase shade, which leads to shoot elongation and protection against freezing. However, the possible effect of these colored meshes on the physiological performance of these seedlings is unknown. The objective of this work was to describe the light environment produced by these colored meshes (black, white, blue, green) and to evaluate their effect on growth and physiological performance of Pinus radiata, Eucalyptus nitens and E. globulus seedlings. To evaluate differences among colored meshes, the quality and intensity of light was determined. Seedlings maintained under each mesh were evaluated through the measurement of growth (increasing height of shoots), biomass distribution and vitality (fluorescence of PSII, Fv/Fm). Results show that black and white mesh influences were not selective on their transmittance spectrum and only provided shade (70 % and 50 %, respectively). Vitality measurements did not show damage in seedlings. Seasonal variation on growth was observed, with the highest values during fall and spring for P. radiata and only in spring for both Eucalyptus spp. White mesh promotes higher growth only on both Eucalyptus species, thus it would be recommended for nursery practices. © 2019, Universidad Austral de Chile. All rights reserved. |
| Comentarios Centro de Ciencia del Clima y la Resiliencia (CR)2 a la consulta ciudadana de primera actualización 2019 de la Contribución Determinada a Nivel Nacional (NDC) de Chile. Diciembre 2019 | Centro de Ciencia del Clima y la Resiliencia (CR)2 | 2019 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2019/12/Resumen-Comentarios-CR2_NDC-2019_02122019.pdf | |||||||||
| A Multiscale Productivity Assessment of High Andean Peatlands across the Chilean Altiplano Using 31 Years of Landsat Imagery | Remote Sensing | Chávez, R.; Christie, D.; Olea, M.; Anderson, T. | 2019 | Agua y Extremos | 10.3390/rs11242955 | https://www.mdpi.com/2072-4292/11/24/2955 | 2955 | Vol: 11 Issue: 24 | 2072-4292 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | The high Andean peatlands, locally known as “bofedales”, are a unique type of wetland distributed across the high-elevation South American Altiplano plateau. This extensive peatland network stores significant amounts of carbon, regulates local and regional hydrological cycles, supports habitats for a variety of plant and animal species, and has provided critical water and forage resources for the livestock of the indigenous Aymara communities for thousands of years. Nevertheless, little is known about the productivity dynamics of the high Andean peatlands, particularly in the drier western Altiplano region bordering the Atacama desert. Here, we provide the first digital peatland inventory and multiscale productivity assessment for the entire western Altiplano (63,705 km2) using 31 years of Landsat data (about 9000 scenes) and a non-parametric approach for estimating phenological metrics. We identified 5665 peatland units, covering an area of 510 km2, and evaluated the spatiotemporal productivity patterns at the regional, peatland polygon, and individual pixel scales. The regional assessment shows that the peatland areas and peatlands with higher productivity are concentrated towards the northern part of our study region, which is consistent with the Altiplano north–south aridity gradient. Regional patterns further reveal that the last seven years (2011–2017) have been the most productive period over the past three decades. While individual pixels show contrasting patterns of reductions and gains in local productivity during the most recent time period, most of the study area has experienced increases in annual productivity, supporting the regional results. Our novel database can be used not only to explore future research questions related to the social, biological, and hydrological influences on peatland productivity patterns, but also to provide technical support for the sustainable development of livestock practices and conservation and water management policy in the Altiplano region. |
| GIMMS NDVI time series reveal the extent, duration, and intensity of “blooming desert” events in the hyper-arid Atacama Desert, Northern Chile | International Journal of Applied Earth Observation and Geoinformation | Chávez, R.; Moreira-Muñoz, A.; Galleguillos, M.; Olea, M.; Aguayo, J.; Latín, A.; Aguilera-Betti, I.; Muñoz, A.; Manríquez, H. | 2019 | Agua y Extremos; Cambio de Uso de Suelo | 10.1016/j.jag.2018.11.013 | https://linkinghub.elsevier.com/retrieve/pii/S0303243418306202 | 193-203 | Vol: 76 | 0303-2434 | Thomson Reuters ISI (SCIE) | English | The “blooming desert”, or the explosive development and flowering of ephemeral herbaceous and some woody desert species during years with abnormally high accumulated rainfall, is a spectacular biological phenomenon of the hyper-arid Atacama Desert (northern Chile) attracting botanists, ecologists, geo-scientists, and the general public from all over the world. However, the number of “blooming deserts”, their geographical distribution and spatio-temporal patterns have not been quantitatively assessed to date. Here, we used NDVI data from the Global Inventory Modeling and Mapping Studies (GIMMS) project to reconstruct the annual land surface phenology (LSP) of the Atacama Desert using a non-parametric statistical approach. From the reconstructed LSP, we detected the “blooming deserts” as positive NDVI anomalies and assessed three dimensions of the events: their temporal extent, intensity of “greening” and spatial extent. We identified 13 “blooming deserts” between 1981 and 2015, of which three (1997–98, 2002–03, and 2011) can be considered major events according to these metrics. The main event occurred in 2011, spanning 180 days between July and December 2011, and spread over 11,136 km 2 of Atacama dry plains. “Blooming deserts” in Atacama have been triggered by the accumulation of precipitation during a period of 2 to 12 months before and during the events. The proposed three-dimensional approach allowed us to characterize different types of “blooming deserts”: with longer episodes or larger spatial distribution or with different “greening” intensities. Its flexibility to reconstruct different LSP and detect anomalies makes this method a useful tool to study these rare phenomena in other deserts in the world also. | |
| Centennial‐Scale SE Pacific Sea Surface Temperature Variability Over the Past 2,300 Years | Paleoceanography and Paleoclimatology | Collins, J.; Lamy, F.; Kaiser, J.; Ruggieri, N.; Henkel, S.; De Pol‐Holz, R.; Garreaud, R.; Arz, H. | 2019 | Agua y Extremos; Cambio de Uso de Suelo | 10.1029/2018PA003465 | https://onlinelibrary.wiley.com/doi/abs/10.1029/2018PA003465 | 336-352 | Vol: 34 | 2572-4517 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Detailed temperature reconstructions over the past 2,000 years are important for contextualizing modern climate change. The midlatitude SE Pacific is a key region in this regard in terms of understanding the climatic linkages between the tropics and southern high latitudes. Multicentennial timescale temperature variability remains, however, poorly understood, due to a lack of long, high-temporal-resolution temperature records from this region and from the southern high latitudes in general. We present a unique alkenone sea surface temperature (SST) record from 44°S on the southern Chilean margin in the SE Pacific spanning the last 2,300 years at decadal resolution. The record displays relatively large changes including a cooling transition from 14 to 12.5 °C between 1,100 and 600 cal yr BP, in line with other Chile margin SST records and coeval with Antarctic cooling. This cooling is attributable to reduced Southern Ocean deep convection, driven by a late Holocene sea-ice increase in the Weddell Sea associated with increased El-Niño Southern Oscillation variability. Superimposed on the late Holocene cooling, we observe multicentennial timescale SST variability, including relatively cool SSTs (12.5 °C) from 950 to 500 cal yr BP, corresponding to the Medieval Climate Anomaly, and warmer SSTs (13 °C) from 500 to 200 cal yr BP, corresponding to the Little Ice Age. These oscillations may reflect either multicentennial internal variability of the Southern Ocean deep convection and/or multicentennial variability in the phasing of El-Niño Southern Oscillation and Southern Annular Mode events. ©2019. American Geophysical Union. All Rights Reserved. |
| Growth and steady state of the Patagonian Andes | American Journal of Science | Colwyn, D.; Brandon, M.; Hren, M.; Hourigan, J.; Pacini, A.; Cosgrove, M.; Midzik, M.; Garreaud, R.; Metzger, C. | 2019 | Agua y Extremos | 10.2475/06.2019.01 | http://www.ajsonline.org/lookup/doi/10.2475/06.2019.01 | 431-472 | Vol: 319 Issue: 6 | 0002-9599 | Thomson Reuters ISI (SCIE) | English | Water isotopes are an important tool for reconstructing the amount of atmospheric lifting related to high topography in the geologic past. However, our capacity for meaningful interpretation requires understanding the climatic setting and isolating the influence of orography on water isotopes. Patagonia’s simple, steady climatology and location within the Southern Westerlies makes it an ideal setting for successful application of water isotopes to measuring topography through time. Here we use hydrated volcanic glass to construct a new record of the size of the Patagonian Andes during the Cenozoic. We also utilize a novel method for identifying the contribution of orography in regional climate records. Our results show that variation in the observed record can largely be explained by variations in climate. Thus we conclude that the mountain range has maintained a size similar to modern since at least Paleocene. This result is in agreement with geologic data, which constrain the bulk of the surface uplift of the Andes to the Cretaceous. The reconstruction of the Patagonian Andes, which grew in the Cretaceous and remained high through the Cenozoic, is markedly different from the widely held view of Miocene formation of this mountain range. In particular, the topography appears to remain stable during the northward propagation and collision of offshore spreading centers. |
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| Managing Forests for Both Downstream and Downwind Water | Frontiers in Forests and Global Change | Creed, I.; Jones, J.; Archer, E.; Claassen, M.; Ellison, D.; McNulty, S.; van Noordwijk, M.; Vira, B.; Wei, X.; Bishop, K.; Blanco, J.; Gush, M.; Gyawali, D.; Jobbágy, E.; Lara, A.; Little, C.; Martin-Ortega, J.; Mukherji, A.; Murdiyarso, D.; Pol, P.; Sullivan, C.; Xu, J. | 2019 | Cambio de Uso de Suelo | 10.3389/ffgc.2019.00064 | https://www.frontiersin.org/article/10.3389/ffgc.2019.00064/full | 64 | Vol: 2 | 2624-893X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Forests and trees are key to solving water availability problems in the face of climate change and to achieving the United Nations Sustainable Development Goals. A recent global assessment of forest and water science posed the question: How do forests matter for water? Here we synthesize science from that assessment, which shows that forests and water are an integrated system. We assert that forests, from the tops of their canopies to the base of the soils in which trees are rooted, must be considered a key component in the complex temporal and spatial dimensions of the hydrologic cycle. While it is clear that forests influence both downstream and downwind water availability, their actual impact depends on where they are located and their processes affected by natural and anthropogenic conditions. A holistic approach is needed to manage the connections between forests, water and people in the face of current governance systems that often ignore these connections. We need policy interventions that will lead to forestation strategies that decrease the dangerous rate of loss in forest cover and that—where appropriate—increase the gain in forest cover. We need collective interventions that will integrate transboundary forest and water management to ensure sustainability of water supplies at local, national and continental scales. The United Nations should continue to show leadership by providing forums in which interventions can be discussed, negotiated and monitored, and national governments must collaborate to sustainably manage forests to ensure secure water supplies and equitable and sustainable outcomes. |
| Comité Científico COP25: Propuesta para la actualización de Plan de Adaptación en Pesca y Acuicultura | Farías, L.; Acuña, E.; Aguirre, C.; Álvarez, S.; Barbieri, M.; Delgado, V.; Dewitte, B.; Espinoza, Ó.; Fernández, C.; Garrido, P.; Jacob, B.; Lagos, N.; Masotti, I.; Narváez, D.; Navarrete, S.; Pérez-Santos, I.; Pinilla, E.; Ramajo, L.; Saavedra, L.; Silva, C.; Soto, D.; Troncoso, L.; Vargas, C.; Ve... | 2019 | Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2019/12/Propuesta-de-actualización-para-Plan-de-Adaptación.pdf | 1-87 | English | El Plan de Adaptación al Cambio Climático en Pesca y Acuicultura (PACCPA) es un instrumento articulador que delinea acciones y medidas relativas a políticas públicas y gestión pesquera y acuícola, con el objetivo de fortalecer la capacidad de adaptación del sector al cambio climático. La Mesa Océanos del Comité Científico COP25 presenta esta propuesta para la actualización y mejoramiento del PACCPA a la luz de los cambios físicos, químicos y biológicos que afectan al océano, sean estos observados o proyectados; para la evaluación de diferentes tipos de riesgos en la zona costera y otros antecedentes socioeconómicos, jurídicos, normativos y de gobernanza que impactan positiva o negativamente sobre la actividad pesquera y acuícola. El presente documento entrega observaciones y argumentos relativos a los 5 objetivos específicos y 29 acciones delineadas en el primer PACCPA (2015-2020); además, introduce 16 nuevas acciones asociadas a tres de los objetivos ya planteados y agrega dos nuevos objetivos específicos relativos a fomentar e incentivar la economía circular y fortalecer el rol de la mujer, para una mejor adaptación de las comunidades costeras. Se introducen los nuevos antecedentes de: gobernanza climática internacional, en los cuales Chile tiene compromisos, institucionalidad nacional y del marco normativo y jurídico con el cual administra y gestiona los recursos marinos y la zona costera. Se releva la necesidad de reformar el concepto de enfoque ecosistémico y principio precautorio de la Ley de Pesca y Acuicultura en un contexto de cambio climático y, explícitamente, de incorporar la actividad acuícola bajo estos conceptos. Existe consenso de que la armonización de las estructuras de gobernanza local y/o macrozonas proporcionarán una política general de acción y asignación de recursos necesarios para la adaptación. Se analizan, además, los procesos y las variables oceanográficas y climáticas que afectan a las pesquerías y a la acuicultura (no todas consideradas en el primer PACCPA), como acidificación, desoxigenación, estratificación, aumento de la intensidad de la surgencia y de la frecuencia de eventos El Niño, entre otros, además de riesgos e impactos del aumento del nivel del mar y marejadas para el sector. Se resalta la necesidad de profundizar en el conocimiento de parámetros biológicos relacionados con la reproducción, la alimentación y la sobrevivencia de los recursos pesqueros y de cultivo a diferentes edades. Con el análisis de planes existentes y nuevas evidencias, se levantaron brechas de conocimiento, gobernanza, ambientales y socioeconómicas; estas últimas importantes de ponderar, pues los trabajadores de este sector son los que reciben los más bajos ingresos, poseen un menor nivel de educación y de salud y, por ello, son más vulnerables. En este contexto, el cambio climático profundiza las desigualdades y es un multiplicador de amenazas. Se indica que muchas variables/procesos que afectan a los recursos biológicos (amenazas) no deben ser analizados individualmente, sino como multi-amenazas, debido a la correlación que existe entre ellos; asimismo, se debe realizar un fortalecimiento institucional, sistematizar y profundizar el conocimiento científico. Relativo a esto último, se repite una y otra vez la necesidad de un Sistema Integrado de Observación del Océano Chileno (SIOOC) y el uso y mejoramiento de modelos regionales propios; donde se acoplen modelos oceanográficos con los pesqueros con fines de predicción y comprensión de los mecanismos que entran en juego, entre los recursos pesqueros y el efecto antrópico (como la sobrepesca), separando así la variabilidad ambiental del cambio climático y la capacidad de adaptación. Respecto a la acuicultura, también se requiere por una parte una evaluación profunda y analítica del impacto a nivel macro y microbiológico que ejercen los centros de cultivo sobre su entorno y cómo estos pueden exacerbar la crisis climática en curso; además de cuantificar cómo los efectos del cambio climático (aumento de temperatura, cambios en corrientes, acidificación, salinidad, oxigenación, etc.) impactan la sostenibilidad y productividad del sector. Finalmente, se concluye y recomienda que es vital incluir los aspectos socioeconómicos, de gobernanza y financiamiento al nuevo PACCPA, considerando la diversidad de amenazas, pero también las oportunidades que se presentan para el sector |
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| Comité Científico COP25: Océano y Cambio Climático. 50 preguntas y respuestas | Farías, L.; Aguilera, V.; Aguirre, C.; Barbieri, M.; Castillo-Silva, M.; Contreras-López, M.; Dewitte, B.; Echeveste, P.; Fernández, C.; Gómez-Canchong, P.; Lagos, N.; Lara, L.; Marquet, P.; Miquel, J.; Molina, M.; Montecino, V.; Morales, M.; Narváez, D.; Navarrete, S.; Oliveros-Clavijo, V.; Quiroga... | 2019 | Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2019/10/El-ABC-del-Océano-y-el-cambio-Cimático.pdf | 1-107 | Spanish | Todos los que habitamos el planeta dependemos directa o indirectamente del océano. Este provee alimento, transporte, cultura y, a través del intercambio de agua, energía y carbono; asimismo, es sustento de hábitats únicos que han sido dañados progresivamente por los efectos del cambio climático. A nivel global 680 millones de personas habitan zonas costeras. En Chile, nuestra relación es todavía más estrecha. Debido a nuestra extensa geografía, un cuarto de la población se distribuye en 100 comunas costeras donde más de 500 caletas dan sustento a 90 mil trabajadores vinculados a la pesca artesanal. La creciente y cada vez más contundente evidencia científica sobre el impacto del cambio climático en los ecosistemas marinos revela la vulnerabilidad a la que se exponen los habitantes y otros seres vivos de estos territorios, y, por lo mismo, es un llamado urgente que nos moviliza a la acción. Como Ministerio de Ciencia, Tecnología, Conocimiento e Innovación trabajamos activamente con la comunidad científica para utilizar la evidencia en el diseño de políticas que nos permitan sobreponernos y anticiparnos a los efectos del cambio climático. En esta búsqueda, y con motivo de la cumbre de acción climática COP25, hemos impulsado la organización del Comité Científico que reúne a más de 550 investigadores nacionales del cambio climático. Este trabajo busca contribuir directamente al tránsito que necesitamos desde la evidencia a la acción climática ambiciosa y factible. Las siguientes páginas son el resultado del esfuerzo colectivo de los investigadores e investigadoras de la mesa Océanos de este comité. Este documento es un aporte al debate ciudadano y a la necesaria sensibilización sobre la importancia de nuestro océano. Solo si logramos comprender en profundidad procesos como el aumento del nivel del mar, sus cambios de temperatura, acidificación, oxigenación, eventos extremos asociados al océano y la pérdida de biodiversidad que enfrenta, podremos impulsar medidas de adaptación y mitigación que apunten a un desarrollo sostenible e integral en beneficio de las personas y el medioambiente que lo permite. |
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| Nitrous oxide and biogeochemical variables related to Intermediate Waters into Eastern South Pacific Ocean, supplement to: Carrasco, Cristina; Karstensen, Johannes; Farías, Laura (2017): On the Nitrous Oxide Accumulation in Intermediate Waters of the Eastern South Pacific Ocean. Frontiers in Marine Science, 4 | Farías, L.; Carrasco, C.; Faúndez, J. | 2019 | Zonas Costeras | 10.1594/PANGAEA.906231 | https://doi.pangaea.de/10.1594/PANGAEA.906231 | Pangaea | English | Nitrous oxide (N2O) is a powerful greenhouse gas principally produced by nitrification and denitrification in the marine environment. Observations were made in the eastern South Pacific (ESP), between 10º and 60°S, and ~75° to 88°W, from intermediate waters targeting Antarctic Intermediate Water (AAIW) at potential density of 27.0-27.1 kg m-3. Between 60° to 20°S, a gradual equatorward increase of N2O from 8 to 26 nmol L-1 was observed at density 27.0-27.1 kg m-3 where AAIW penetrates. Positive correlations were found between apparent N2O production (∆N2O) and O2 utilization (AOU), and between ∆N2O and NO3-, which suggested that local N2O production is predominantly produced by nitrification. Closer to the equator, between 20° and 10°S at AAIW core, a strong N2O increase up to 75 nmol L-1 was observed. Because negative correlations were found between ∆N2O vs. NO3- and ∆N2O vs. N* (a Nitrogen deficit index) and because ∆N2O and AOU do not follow a linear trend, we suspect that, in addition to nitrification, denitrification also takes place in N2O cycling. By making use of water mass mixing analyses, we show that an increase in N2O occurs in the region where high oxygen from AAIW merges with low oxygen from Equatorial Subsurface Water (ESSW), creating favorable conditions for local N2O production. We conclude that the non-linearity in the relationship between N2O and O2 is a result of mixing between two water masses with very different source characteristics, paired with the different time frames of nitrification and denitrification processes that impact water masses en route before they finally meet and mix in the ESP region. | |||||
| Comité Científico COP25: Propuesta de un Sistema Integrado de Observación del Océano Chileno | Farías, L.; Fernández, C.; Garreaud, R.; Guzmán, L.; Hormazábal, S.; Morales, C.; Narváez, D.; Pantoja, S.; Pérez, I.; Soto, D.; Winckler, P. | 2019 | Agua y Extremos; Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2019/12/Propuesta-de-sistema-integrado-de-observación-del-océano.pdf | 1-27 | Spanish | Chile ocupa el décimo puesto a nivel mundial con mayor territorio marítimo y el primer lugar en Latinoamérica con mayor superficie de mar. El país es dependiente del océano en términos económicos, sociales y culturales, que incluyen actividades en la zona costera y oceánica. Al mismo tiempo, los procesos climáticos y oceanográficos constituyen constantes fuentes de riesgo e incertidumbre, aumentando la vulnerabilidad en los socio-ecosistemas marinos. Chile está declarado un país altamente vulnerable al cambio climático, basado en estudios derivados de la Agenda 2030 para el Desarrollo Sostenible de las Naciones Unidas. Esto obliga a buscar propuestas y soluciones para abordar esta vulnerabilidad. A nivel internacional, varios países han desarrollado e implementado sistemas integrados de observación del océano basados en información continua sobre su estado y sus recursos, con el objetivo de abordar de forma operacional la vulnerabilidad. Estos sistemas de observación tienen propósitos, tales como, mejorar la seguridad en operaciones marinas, fortalecer la seguridad alimentaria, apoyar las actividades económicas de pequeña y gran escala, reducir el riesgo frente a desastres naturales y disminuir la incertidumbre económica junto con la conflictividad social y ambiental derivada de esta. El océano chileno está afecto a una serie de procesos globales asociados al cambio climático, regionales y locales que necesitan, ser estudiados y monitoreados. Por lo tanto, se requiere de la existencia de un sistema de registro continuo de variables atmosféricas y oceanográficas, que provea la información necesaria para la toma de decisiones, tanto públicas como privadas, y permita realizar análisis retrospectivos y predictivos del estado del océano. Actualmente, existen en Chile algunas iniciativas de observación y monitoreo del océano, incluyendo aportes de servicios públicos, instituciones académicas y organizaciones privadas. Sin embargo, estas no son sistémicas y carecen de continuidad, principalmente por falta de instrumentos financieros de largo aliento y de la valoración política de la información. En el compromiso nacional e internacional, el Comité Científico COP25 releva la importancia de contar con información basada en la evidencia para planificar estratégicamente el desarrollo sostenible y la equidad intergeneracional respecto del uso y la conservación del océano, de los ecosistemas marinos y sus servicios a la humanidad. En este escenario, académicos, servidores públicos y agentes del sector privado con competencia en la materia proponen gestar un Sistema Integrado de Observación del Océano Chileno (SIOOC), que permita disponer de datos de calidad, estandarizados y de acceso público para el estudio, monitoreo, manejo y vigilancia del océano y sus recursos. Se contemplan para la implementación del SIOOC, basado en la experiencia existente y las necesidades o brechas del Chile, tres fases en un horizonte de 6 a 8 años: › Primero, consolidar la integración de los sistemas existentes en una red asociativa y bajo una gobernanza apropiada, con recursos humanos y financiamiento de fuentes múltiples, e incluyendo la participación del sector privado, productivo y de la sociedad civil. › Segundo, incorporar al sistema de nuevos equipamientos e infraestructura (primario y secundario), con un análisis de las capacidades habilitantes y la transferencia tecnológica necesaria para aumentar el tipo, número y cobertura de las observaciones, además de fortalecer las capacidades de predicción. › Tercero, incorporar en pleno del SIOOC a otras redes internacionales, especialmente en zonas de alto interés, como la zona antártica, aguas internacionales e islas oceánicas. Las universidades y los servicios del Estado participantes en esta propuesta comprometen la infraestructura y los conocimientos existentes para dar lanzamiento al SIOOC. A su vez, esperan que el Estado tome esta iniciativa y un compromiso nacional e internacional como una acción para proteger nuestros mares. |
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| Comité Científico COP25: Nueve medidas basadas en el océano para las Contribuciones Determinadas a nivel Nacional de Chile | Farías, L.; Ubilla, K.; Aguirre, C.; Bedriñana, L.; Cienfugos, R.; Delgado, V.; Fernández, C.; Fernández, M.; Gaxiola, A.; González, H.; Hucke-Gaete, R.; Marquet, P.; Montencino, V.; Morales, C.; Narváez, D.; Osses, M.; Peceño, B.; Quiroga, E.; Ramajo, L.; Sepúlveda, H.; Soto, D.; Vargas, E.; Viddi,... | 2019 | Ciudades Resilientes; Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2019/12/Nueve-soluciones-para-NDC.pdf | 1-93 | English | Las Contribuciones Determinadas a nivel Nacional (NDC, por sus siglas en inglés) se han convertido en un instrumento clave para comprometer principalmente metas de mitigación y adaptación al cambio climático. Gestadas en el Acuerdo de París (2015) aspiran a cumplir dos de sus objetivos más ambiciosos: mantener el incremento de la temperatura global muy por debajo de los 2°C, respecto a la era preindustrial, y fortalecer y aumentar la capacidad de adaptación y resiliencia a los efectos adversos del cambio climático. La actualización de las NDC el año 2020 las llevará a convertirse en un instrumento ambicioso y con trazabilidad, luego de la declaración de limitar a 1.5 °C el incremento de temperatura al 2030 (IPCC, 2018) y la cumbre del clima de Katowice (COP24). Chile, ejerciendo la presidencia de la COP25, se debe comprometer a metas más ambiciosas, transparentes y progresivas, entre ellas, la carbono- neutralidad, la COP azul y la economía circular. La mesa Océanos del Comité Científico COP25, a partir de una metodología participativa y colaborativa, propone nueve medidas basadas en el océano, para contribuir a la meta de reducción de sus emisiones, y realiza un análisis de los alcances que tiene la primera propuesta de actualización de las NDC (2020) en el tema océano. Las medidas propuestas en este informe colindan con acciones que: 1) favorecen el secuestro de carbono, como soluciones basada en naturaleza (carbono azul); 2) reducen las emisiones de gases con efecto invernadero (GEI) en la economía del océano; y 3) abordan la vulnerabilidad, riesgos e impactos del cambio climático en el sector pesca y acuicultura, enfocándose en la inequidad social y de género, y la construcción de capacidades relativa a implementar un sistema observación del océano y reducir brechas en su conocimiento, gestión y administración. Se refuerza en el concepto de entierro de carbono como el resultado del funcionamiento a largo plazo de una compleja red de procesos del ciclo del carbono, donde los sedimentos marinos y suelos costeros se constituyen como el mayor reservorio de largo aliento de carbono en el planeta. Al respecto, se reúnen antecedentes de la ventaja competitiva que tiene Chile respecto a la protección de fondos marinos, marismas y bosques de algas pardas; ecosistemas de fundamental importancia para la mitigación del cambio climático, pero, específicamente, vulnerables a su impacto y a la acción humana. Respecto a la economía del océano, la reducción de la emisión de GEI por parte de actividades como el transporte marítimo, acuicultura y el uso de energías marinas son medidas muy factibles e internacionalmente comprobadas, cuyos costos-beneficios van en directa relación con los compromisos y mercados internacionales. Este es especialmente relevante para la acuicultura y la economía circular. Finalmente, para adaptarse deben existir capacidades en un Sistema Integrado de Observación del Océano Chileno (SIOOC) que incluya alertas ambientales tempranas y proyecciones, de modo de reducir riesgos y conflictividades ambientales y sociales, y disminuir las brechas de conocimiento, de gobernanza y económicas respecto al océano. Lo que importa es transformar los compromisos en acciones/medidas trazables, y al respecto, dada su vocación oceánica y su dependencia a este medio, Chile debe tener unas NDC ambiciosas que incluyan los hábitats y ecosistemas marinos (carbono azul) en los presupuestos de carbono nacional (además de las contribuciones en materia de cambio de uso de la tierra y silvicultura, UTCUTS), declarar co-beneficios, dar valoración económica de los servicios ecosistémicos ambientales, y formular políticas públicas dirigidas a la conservación. El presente informe releva la necesidad de generar voluntad política para fortalecer el marco normativo y/o legislativo que permita proteger a los sistemas costeros que cumplen importantes funciones para el cambio climático; fortalecer la capacidad adaptativa de las comunidades pesqueras y acuicultoras, y comprometer Áreas Marinas Protegidas con planes de manejo al corto plazo de modo de aumentar el nivel de ambición y alcanzar la carbono neutralidad. | ||||||
| Bacterial community structure in a sympagic habitat expanding with global warming: brackish ice brine at 85–90 °N | The ISME Journal | Fernández-Gómez, B.; Díez, B.; Polz, M.; Arroyo, J.; Alfaro, F.; Marchandon, G.; Sanhueza, C.; Farías, L.; Trefault, N.; Marquet, P.; Molina-Montenegro, M.; Sylvander, P.; Snoeijs-Leijonmalm, P. | 2019 | Zonas Costeras | 10.1038/s41396-018-0268-9 | http://www.nature.com/articles/s41396-018-0268-9 | 316–333 | Vol: 13 | 1751-7362 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | Larger volumes of sea ice have been thawing in the Central Arctic Ocean (CAO) during the last decades than during the past 800,000 years. Brackish brine (fed by meltwater inside the ice) is an expanding sympagic habitat in summer all over the CAO. We report for the first time the structure of bacterial communities in this brine. They are composed of psychrophilic extremophiles, many of them related to phylotypes known from Arctic and Antarctic regions. Community structure displayed strong habitat segregation between brackish ice brine (IB; salinity 2.4–9.6) and immediate sub-ice seawater (SW; salinity 33.3–34.9), expressed at all taxonomic levels (class to genus), by dominant phylotypes as well as by the rare biosphere, and with specialists dominating IB and generalists SW. The dominant phylotypes in IB were related to Candidatus Aquiluna and Flavobacterium, those in SW to Balneatrix and ZD0405, and those shared between the habitats to Halomonas, Polaribacter and Shewanella. A meta-analysis for the oligotrophic CAO showed a pattern with Flavobacteriia dominating in melt ponds, Flavobacteriia and Gammaproteobacteria in solid ice cores, Flavobacteriia, Gamma- and Betaproteobacteria, and Actinobacteria in brine, and Alphaproteobacteria in SW. Based on our results, we expect that the roles of Actinobacteria and Betaproteobacteria in the CAO will increase with global warming owing to the increased production of meltwater in summer. IB contained three times more phylotypes than SW and may act as an insurance reservoir for bacterial diversity that can act as a recruitment base when environmental conditions change. |
| Techno-political definitions of the configuration of the Chilean energy matrix throughout the twentieth century | Historia (Santiago) | Folchi, M.; Blanco-Wells, G.; Meier, S. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.4067/S0717-71942019000200373 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-71942019000200373&lng=en&nrm=iso&tlng=en | 373-408 | Vol: 52 Issue: 2 | 0717-7194 | Thomson Reuters ISI (AHCI) | English | The article examines the historical configuration of the Chilean energy matrix throughout the twentieth century and understands it as the result of the relative expansion and decline of three interdependent socio-technical regimes: coal, petroleum and electricity. For each of these regimes the article studies the techno-political definitions that guided its development. These definitions were represented as “problems” by the elites of an ideological, social or economic nature, which should be resolved by the State and the private sector. | |
| Summer phyto- and bacterioplankton communities during low and high productivity scenarios in the Western Antarctic Peninsula | Polar Biology | Fuentes, S.; Arroyo, J.; Rodríguez-Marconi, S.; Masotti, I.; Alarcón-Schumacher, T.; Polz, M.; Trefault, N.; De la Iglesia, R.; Díez, B. | 2019 | Zonas Costeras | 10.1007/s00300-018-2411-5 | https://link.springer.com/10.1007/s00300-018-2411-5 | 159-169 | Vol: 42 Issue: 1 | 0722-4060, 1432-2056 | Thomson Reuters ISI (SCIE) | English | Phytoplankton blooms taking place during the warm season drive high productivity in Antarctic coastal seawaters. Important temporal and spatial variations exist in productivity patterns, indicating local constraints influencing the phototrophic community. Surface water in Chile Bay (Greenwich Island, South Shetlands) is influenced by freshwater from the melting of sea ice and surrounding glaciers; however, it is not a widely studied system. The phyto- and bacterioplankton communities in Chile Bay were studied over two consecutive summers; during a low productivity period (chlorophyll a < 0.05 mg m−3) and an ascendant phototrophic bloom (chlorophyll a up to 2.38 mg m−3). Microbial communities were analyzed by 16S rRNA—including plastidial—gene sequencing. Diatoms (mainly Thalassiosirales) were the most abundant phytoplankton, particularly during the ascendant bloom. Bacterioplankton in the low productivity period was less diverse and dominated by a few operational taxonomic units (OTUs), related to Colwellia and Pseudoalteromonas. Alpha diversity was higher during the bloom, where several Bacteroidetes taxa absent in the low productivity period were present. Network analysis indicated that phytoplankton relative abundance was correlated with bacterioplankton phylogenetic diversity and the abundance of several bacterial taxa. Hubs—the most connected OTUs in the network—were not the most abundant OTUs and included some poorly described taxa in Antarctica, such as Neptunomonas and Ekhidna. In summary, the results of this study indicate that in Antarctic Peninsula coastal waters, such as Chile Bay, higher bacterioplankton community diversity occurs during a phototrophic bloom. This is likely a result of primary production, providing a source of fresh organic matter to bacterioplankton. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature. | |
| Informe a las naciones: El Antropoceno en Chile: evidencias y formas de avanzar | Gallardo, L.; Rudnick, A.; Barraza, J.; Fleming, Z.; Rojas, M.; Gayo, E.; Aguirre, C.; Farías, L.; Boisier, J.; Garreaud, R.; Barría, P.; Miranda, A.; Lara, A.; Gómez-González, S.; Arriagada, R. | 2019 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2019/06/Informe-Antropoceno-castellano.pdf | 40 | cr2.cl | English | En el siglo XXI, el desarrollo de Chile está en juego debido a las amenazas planteadas por el Antropoceno. Esta época se caracteriza por la influencia humana sobre el sistema terrestre. Sin embargo, si se enfrenta con audacia, ofrece una oportunidad para un desarrollo sostenible. Independientemente de si hemos entrado en una nueva era geológica, el Antropoceno cuestiona nuestra forma de vivir en el planeta azul del sistema solar. O, dicho de otra manera, la forma de entender el progreso y el desarrollo. En un país con grandes desigualdades sociales, altamente vulnerable al cambio global, enfrentar este desafío es de crucial importancia y puede ofrecer nuevas oportunidades. | |||||
| ¿Dónde esta lloviendo? Pregúntale a Vismet | Bits de Ciencias (DCC-UCH) | Garreaud, R.; Bastarrica, M. | 2019 | Agua y Extremos | https://www.dcc.uchile.cl/Bitsdeciencia17.pdf | 8-13 | Issue: 17 | Spanish | La meteorología es una ciencia que tiene dos pilares. Uno de ellos es el conjunto de leyes físicas de la atmósfera y otras componentes del sistema terrestre. Su integración numérica requiere grandes capacidades computacionales y permite el pronóstico del tiempo ("forecasting") hasta dos semanas en el futuro. El otro pilar es el mundo de las observaciones, sin las cuales no se podrían inicializar los modelos, contrastar sus resultados y hacer sentido de múltiples fenómenos atmosféricos. Más aún, el pronóstico meteorológico de muy corto plazo (0-6 horas) se basa mayormente en un tratamiento estadístico de las condiciones observadas actuales y pasadas. El así llamado "nowcasting" es de especial valor en condiciones extremas; por ejemplo, para determinar si ocurrirá una crecida súbita en algún cajón cordillerano necesitamos saber qué está pasando ahora en la cordillera. |
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| Procurement of camelid fiber in the hyperarid Atacama Desert coast: Insights from stable isotopes | Quaternary International | Gayo, E.; Martens, T.; Stuart-Williams, H.; Fenner, J.; Santoro, C.; Carter, C.; Cameron, J. | 2019 | Ciudades Resilientes | 10.1016/j.quaint.2019.12.008 | https://linkinghub.elsevier.com/retrieve/pii/S1040618219309322 | 71-83 | Vol: 548 | 10406182 | Thomson Reuters ISI (SCIE) | English | Pastoralism and camelid management are traditionally attributed to the sociopolitical, economic and cosmovision of Andean populations, rather than to lowland hunter gatherer societies, living on the Pacific coast where camelid hunting is considered a marginal activity, and husbandry is a difficult enterprise given the hyper-arid conditions of lowland terrestrial ecosystems. Contrary to this interpretative historical view, our stable isotope analyses applied to 48 camelid fiber samples, suggests this highly valued camelid byproduct was obtained from camelids sustained on lomas vegetation formations during the Archaic (ca. 6500-4000 cal yr BP), Formative (ca. 4000-1500 cal yr BP) and Late periods (ca. 660-480 cal yr BP). | |
| Geohistorical records of the Anthropocene in Chile | Elem Sci Anth | Gayo, E.; McRostie, V.; Campbell, R.; Flores, C.; Maldonado, A.; Uribe-Rodriguez, M.; Moreno, P.; Santoro, C.; Christie, D.; Muñoz, A.; Gallardo, L. | 2019 | Agua y Extremos; Ciudades Resilientes | 10.1525/elementa.353 | https://www.elementascience.org/article/10.1525/elementa.353/ | 15 | Vol: 7 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The deep-time dynamics of coupled socio-ecological systems at different spatial scales is viewed as a key framework to understand trends and mechanisms that have led to the Anthropocene. By integrating archeological and paleoenvironmental records, we test the hypothesis that Chilean societies progressively escalated their capacity to shape national biophysical systems as socio-cultural complexity and pressures on natural resources increased over the last three millennia. We demonstrate that Pre-Columbian societies intentionally transformed Chile’s northern and central regions by continuously adjusting socio-cultural practices and/or incorporating technologies that guaranteed resource access and social wealth. The fact that past human activities led to cumulative impacts on diverse biophysical processes, not only contradicts the notion of pristine pre-Industrial Revolution landscapes, but suggests that the Anthropocene derives from long-term processes that have operated uninterruptedly since Pre-Columbian times. Moreover, our synthesis suggests that most of present-day symptoms that describe the Anthropocene are rooted in pre-Columbian processes that scaled up in intensity over the last 3000 years, accelerating after the Spanish colonization and, more intensely, in recent decades. The most striking trend is the observed coevolution between the intensity of metallurgy and heavy-metal anthropogenic emissions. This entails that the Anthropocene cannot be viewed as a universal imprint of human actions that has arisen as an exclusive consequence of modern industrial societies. In the Chilean case, this phenomenon is intrinsically tied to historically and geographically diverse configurations in society-environment feedback relationships. Taken collectively with other case studies, the patterns revealed here could contribute to the discussion about how the Anthropocene is defined globally, in terms of chronology, stratigraphic markers and attributes. Furthermore, this deep-time narrative can potentially become a science-based instrument to shape better-informed discourses about the socio-environmental history in Chile. More importantly, however, this research provides crucial “baselines” to delineate safe operating spaces for future socio-ecological systems. |
| Comité Científico COP25: Criósfera Chilena y Antártica: Recomendaciones desde la evidencia científica | González, H.; Bozkurt, D.; Cereceda-Balic, F.; Cordero, R.; Fernandoy, F.; Iriarte, J.; MacDonell, S.; McPhee, J.; Poulin, E.; Rivera, A.; Schaefer, M. | 2019 | Agua y Extremos | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-adaptacion/1.Adaptacion-Brechas-Aldunce.pdf | Chile es uno de los países más vulnerables al cambio climático, principalmente, debido a su configuración biogeográfica. Sus efectos ya se están manifestando, principalmente por una prologada y extensa sequía. En este contexto, es urgente la adopción de medidas de mitigación y adaptación para enfrentar los impactos actuales y los adversos escenarios futuros que predicen los modelos climáticos. La criósfera antártica y andina incluye los hielos continentales y marinos permanentes o estacionales, localizados en la península Antártica (PA) y en la región Subantártica (SANT), junto con el macizo Andino en su conjunto. La criósfera alberga una especial biodiversidad que sustenta una serie de subsistemas ecológicos (p. ej., vegas, bofedales, turberas, glaciares, permafrost, lagos subglaciales, tundras marinas, etc.) y servicios ecosistémicos vitales (agua, recreación, regulación climática, biodiversidad, alimento, turismo, etc.), los que están seriamente amenazados por el cambio climático, con negativas consecuencias para el medio ambiente, el clima y la sociedad (reducción del bienestar humano). La criósfera antártica y andina está siendo muy afectada por el alza global de la temperatura (IPCC, 2019). La pérdida de hielo continental en la Antártica se aceleró más de seis veces en las últimas cuatro décadas, mientras que el 87 % de los glaciares andinos monitoreados en territorio nacional exhiben algún grado de retroceso. Hoy, el hielo perdido por la Antártica es promotor de aproximadamente el 10 % del alza global en el nivel de mar; entretanto, el derretimiento de los glaciares andinos, especialmente aquellos en los Campos de Hielo patagónicos, es el responsable de cerca del 3 % del alza global en el nivel de mar | ||||||||
| Spatial variability of near-surface temperature over the coastal mountains in southern Chile (38°S) | Meteorology and Atmospheric Physics | González, S.; Garreaud, R. | 2019 | Agua y Extremos | 10.1007/s00703-017-0555-4 | http://link.springer.com/10.1007/s00703-017-0555-4 | 89-104 | Vol: 131 Issue: 3 | 0177-7971, 1436-5065 | Thomson Reuters ISI (SCIE) | English | The spatial distribution of the near-surface air temperature over a coastal mountain range in southern Chile [Nahuelbuta Mountains (NM), 38°S, maximum height 1300-m ASL] is investigated using in situ measurements, satellite-derived land-surface temperature, and simulations during the austral winter of 2011. Based on a few selected but representative cases, we found that under rainy conditions—either at day or night—temperature decreases with height close to the moist adiabatic lapse rate (~6.5 °C/km). Likewise, the temperature tends to follow the dry adiabat (~9.8 °C/km) during daytime under dry- and clear-skies conditions. During clear-skies nights, the temperature also decreases with height over the southeastern side of NM, but it often increases (at about 8 °C/km) over the northwestern side of the mountains. This temperature inversion extends up to about 700-m ASL leading to an average temperature contrast of about 7 °C between the northwestern and southeastern sides of Nahuelbuta by the end of dry nights. These dawns also feature substantial temperature differences (>10 °C) among closely located stations at a same altitude. High-resolution numerical simulations suggest that upstream blocking of the prevailing SE flow, hydrostatic mountain waves, and strong downslope winds is responsible for such distinctive nocturnal temperature distribution. © 2017, The Author(s). | |
| Temperature and agriculture are largely associated with fire activity in Central Chile across different temporal periods | Forest Ecology and Management | Gómez-González, S.; González, M.; Paula, S.; Díaz-Hormazábal, I.; Lara, A.; Delgado-Baquerizo, M. | 2019 | Cambio de Uso de Suelo | 10.1016/j.foreco.2018.11.041 | https://linkinghub.elsevier.com/retrieve/pii/S0378112718315962 | 535-543 | Vol: 433 | 0378-1127 | Thomson Reuters ISI (SCIE) | English | Wildfires have important ecological and socio-economic implications worldwide. Identifying the major ecological drivers regulating fire activity across space and time is critical to formulating sustainable policies of landscape planning and management under global change scenarios. However, large scale studies quantifying the relative importance of relevant fire drivers across different time periods are largely lacking. We conducted a high-resolution spatial survey in Central Chile and used structural equation models (SEMs) to evaluate the direct and indirect effects of climate, human impact, land uses, and topography on the number of fires and burned area across two distinct periods of time (2000–2005 and 2011–2016). Mean temperature and agricultural use had the highest direct positive effect on the number of fires and burned area in the two studied periods, and thus were the major ecological predictors of fire activity. Human impact was also an important predictor of fire attributes. Topography had multiple indirect effects on fire activity by regulating land use, temperature, and human impact, but direct effects were negligible. Precipitation seasonality, drought and aridity indexes, native forests, and plantations, were less relevant predictors of fire activity. Even so, our SEMs suggested that areas dominated by native forests tended to have lower number of fires than those covered by croplands or plantations. Our results suggest that fire activity in Central Chile will be highly sensitive to increases in human pressure, land use change and warming by climate change. Because the relative importance of the predictors of fire activity was steady over time, the knowledge derived from this study provides critical insights for preventive fire management and landscape planning. The control of stubble burning, native forest restoration and sustainable forestry management could improve social adaptation to a fire-prone future. | |
| Circulation of Objects and Raw Material in the Atacama Desert, Northern Chile by the End of the Pleistocene | PaleoAmerica | Herrera, K.; Pelegrin, J.; Gayo, E.; Santoro, C. | 2019 | Ciudades Resilientes | 10.1080/20555563.2019.1697999 | https://www.tandfonline.com/doi/full/10.1080/20555563.2019.1697999 | 1-14 | Vol: 5 | 2055-5563, 2055-5571 | Thomson Reuters ISI (ESCI) | English | About 13,000 calendar years ago, the Atacama Desert (18–26°S) was occupied by some of the human groups who had begun to populate South America. The archaeological evidence from six sites located in Pampa del Tamarugal (PdT) it the hyperarid core of the Atacama Desert, including different objects and raw materials, shows a connection with different geographical areas within and outside PdT: (a) local circuits to acquire resources from the Pampa; (b) regional displacements that covered the coast and the Andes, more than 70 km away from PdT; and (c) displacements or interactions at a supra-regional level that connected PdT with the tropical and subtropical forests of South America, more than 600 km away. We propose a preliminary model for the local circuits that covers displacements from 40 minutes to 13 hours walking distance from residential locations to obtain fresh water, wood, rocks for knapping, and hunting activities. | |
| Protecting Patagonian peatlands in Chile | Science | Hoyos-Santillan, J.; Miranda, A.; Lara, A.; Rojas, M.; Sepulveda-Jauregui, A. | 2019 | Cambio de Uso de Suelo; Gobernanza e Interfaz Ciencia y Política | 10.1126/science.aaz9244 | http://www.sciencemag.org/lookup/doi/10.1126/science.aaz9244 | 1207-1208 | Vol: 366 Issue: 6470 | 0036-8075, 1095-9203 | Thomson Reuters ISI (SCIE) | English | In their Letter “Seeing Chile's forest for the tree plantations” (27 September, p. 1388), A. P. Durán and O. Barbosa explain how Chile's current proposal for reducing greenhouse gas emissions (1) inadequately addresses forest management with exotic tree plantations. We agree, but we are even more concerned that the proposal overlooks other ecosystems entirely. Chilean Patagonian peatlands cover 3.1 million hectares (2) and contain approximately 4800 million tons of carbon accumulated over 18,000 years (3, 4). This is 4.7 times more carbon than the aboveground biomass of forests in Chile (4, 5). Peat in Chile is classified as a fossil resource, allowing it to be exploited by the Ministry of Mining (6). Chile should invest in the protection of this important ecosystem. Because of the slow peat accumulation in sub-Antarctic regions (less than 1 mm per year) (4), exploitation of peatlands compromises their carbon sequestration capacity, shifting peatlands from net carbon sinks into net carbon sources (7). Protecting Chile's Patagonian peatlands would help the country achieve carbon neutrality by 2050 (8, 9). To protect the peatlands, Chile must end their classification as fossil resources. Instead, Chile should present peatland preservation as part of its greenhouse gas reduction contributions at the 2019 United Nations Climate Change Conference (COP25) (now planned for Madrid, Spain, instead of Chile). Patagonian peatlands should also be recognized as overlooked carbon sinks of regional importance in Chile's new Climate Change Law (10). | |
| El sentido de la ingeniería en tiempos de cambio climático | Cuadernos de Beauchef. Ciencia, Tecnología y Cultura | Ibarra, C. | 2019 | Gobernanza e Interfaz Ciencia y Política | http://libros.uchile.cl/1049 | 12 | Vol: II | Spanish | |||||
| Summertime precipitation deficits in the southern Peruvian highlands since 1964 | International Journal of Climatology | Imfeld, N.; Barreto Schuler, C.; Correa Marrou, K.; Jacques‐Coper, M.; Sedlmeier, K.; Gubler, S.; Huerta, A.; Brönnimann, S. | 2019 | Zonas Costeras | 10.1002/joc.6087 | https://onlinelibrary.wiley.com/doi/abs/10.1002/joc.6087 | 4497-4513 | Vol: 39 Issue: 11 | 0899-8418 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Precipitation deficits remain a concern to the rural population in the southern Peru-vian highlands and knowledge about their occurrence is lacking because of scarcedata availability. For mountainous regions with sparse station networks, reanalysescan provide valuable information; however, known limitations in reproducing pre-cipitation are aggravated due to unresolved topographical effects. In this study, weassess in a first step the representation of precipitation during the rainy season(January–February–March) in seven reanalysis data sets in comparison to a newlygenerated gridded precipitation data set for Peru. In a second step, we assess sum-mer precipitation deficits in Peru during the second half of the 20th century.In the reanalyses data sets, we find biases strongly influenced by the topography ofthe models and low correlations for the rainy season. Thus, reanalyses do not solvethe problem of data scarcity for this region either. Furthermore, we confirm that ElNiño is not a sufficient stratification criterion for precipitation deficits during therainy season (JFM) in the southern Peruvian highlands. Based on observationalrecords and reanalyses, a considerable fraction of inter-annual variability of precipi-tation can be explained through upper-tropospheric zonal wind anomalies. Westerlywind anomalies, often related to the warming of the troposphere during an El Niñoevent, lead to dry conditions, but not all El Niño events produce these westerly windanomalies. Atmospheric simulations indicate differences between precipitation defi-cits in central Pacific and eastern Pacific El Niño flavours, which cannot beaddressed in observations due to reduced record length: Droughts in the southernPeruvian Andes during eastern Pacific El Niño events seem to be related to a stron-ger warming in the troposphere above the central Pacific ocean, whereas this is notthe case for droughts during central Pacific El Niño events. These results, however,need to be further corroborated by model studies and palaeoclimatological research. |
| A 15,400-year long record of vegetation, fire-regime, and climate changes from the northern Patagonian Andes | Quaternary Science Reviews | Jara, I.; Moreno, P.; Alloway, B.; Newnham, R. | 2019 | Agua y Extremos | 10.1016/j.quascirev.2019.106005 | https://linkinghub.elsevier.com/retrieve/pii/S0277379119305281 | 106005 | Vol: 226 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | Paleoecological studies from the northern Patagonian Andes (40–44°S) have identified past changes in vegetation, fire regimes and paleoclimate since the last glaciation, including variations in strength and position of the Southern Westerly Winds (SWW). The extent to which records west and east of the Andes provide a congruent paleoclimatic history, however, has not been explored in detail in the literature. Physical and biological contrasts are evident between these regions today and are to be expected in paleoclimate reconstructions. In this context, we present pollen and charcoal records from sediment cores collected in Lago Espejo, a small closed-basin lake located in the core sector of the northern Patagonian Andes that spans uninterrupted the last ∼15,400 years. Following glacier withdrawal, the vegetation surrounding Lago Espejo features scattered Nothofagus woodlands, including relatively thermophilous rainforest trees between ∼15,400 and 14,400 cal yr BP. The disappearance of these trees and an abrupt rise in Nothofagus at ∼14,400 cal yr BP mark the establishment of closed-canopy forests during the Antarctic Cold Reversal, followed by increases in the cold-tolerant hygrophilous conifer Podocarpus nubigena during the Younger Dryas (∼12,700–11,500 cal yr BP). The Holocene vegetation consists of Nothofagus-dominated forests with modest variation in composition and structure until the present, attesting to the resilience of these forest communities to climate change and natural disturbance regimes. Rapid deforestation, anthropogenic fires and the establishment of artificial meadows with exotic herbs introduced by Europeans at ∼150 cal yr BP, triggered a rapid, large-magnitude landscape transformation unprecedented in the last 14,000 years. The timing and structure of vegetation changes revealed by the Lago Espejo record suggest that changes in the SWW were the main driver of vegetation and fire regimes in the Andes of northern Patagonia over the last 15,400 years. Comparison between multiple reconstructions from northern Patagonia reveals overall coherent vegetation and fire regime changes in the western and Andean sectors, and a spatially variable and more divergent behaviour in sites located further east. This spatial patter is akin to the present-day correlation between precipitation and SWW in this region. | |
| On the evaluation of adaptation practices: a transdisciplinary exploration of drought measures in Chile | Sustainability Science | Lillo-Ortega, G.; Aldunce, P.; Adler, C.; Vidal, M.; Rojas, M. | 2019 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.1007/s11625-018-0619-5 | http://link.springer.com/10.1007/s11625-018-0619-5 | 1057–1069 | Vol: 14 | 1862-4065 | Thomson Reuters ISI (SCIE) | English | A severe drought has affected central Chile since 2009. Various adaptation responses have been developed, and a participatory process is required to learn from them. To enable this, a transdisciplinary approach was adopted to achieve two objectives: first, to test an approach for assessing the effectiveness of existing measures to respond to drought, specifically to distil strengths and weaknesses of implementation, and developing recommendations; second, to reflect on results from a pilot project conducted to ascertain its potential for scalability in terms of processes employed. The research was organized per the three types of knowledge needed to address complex problems through transdisciplinarity: systems, target and transformation knowledge. Using the recent drought as a boundary object, we conducted the pilot in two locations in Chile where we carried out literature reviews, interviews and focus group discussions were carried out. We identified adaptation measures at national and local scale, a set of which were evaluated applying the Index for the Usefulness of Adaptation Practices (IUPA). Results indicate that through IUPA, we could systematically account for the perceived effectiveness of applied measures. Strengths such as autonomy in the decision-making process emerged as key factors that could also be applied in other contexts, whereas weaknesses such as lack of integration with other policy domains, programs or projects were identified. To address weaknesses, key recommendations were proposed, which are congruent with context-specific expectations, capacities, experiences and knowledge, given that they were articulated by local actors. Results present empirical evidence on the important utility of transdisciplinary approaches in the evaluation of adaptation measures and can support the development of metrics related to adaptation process at the local scale. | |
| Using aboveground vegetation attributes as proxies for mapping peatland belowground carbon stocks | Remote Sensing of Environment | Lopatin, J.; Kattenborn, T.; Galleguillos, M.; Perez-Quezada, J.; Schmidtlein, S. | 2019 | Cambio de Uso de Suelo | 10.1016/j.rse.2019.111217 | https://linkinghub.elsevier.com/retrieve/pii/S0034425719302305 | 111217 | Vol: 231 | 0034-4257 | Thomson Reuters ISI (SCIE) | English | Peatlands are key reservoirs of belowground carbon (C) and their monitoring is important to assess the rapid changes in the C cycle caused by climate change and direct anthropogenic impacts. Frequently, information of peatland area and vegetation type estimated by remote sensing has been used along with soil measurements and allometric functions to estimate belowground C stocks. Despite the accuracy of such approaches, there is still the need to find mappable proxies that enhance predictions with remote sensing data while reducing field and laboratory efforts. Therefore, we assessed the use of aboveground vegetation attributes as proxies to predict peatland belowground C stocks. First, the ecological relations between remotely detectable vegetation attributes (i.e. vegetation height, aboveground biomass, species richness and floristic composition of vascular plants) and belowground C stocks were obtained using structural equation modeling (SEM). SEM was formulated using expert knowledge and trained and validated using in-situ information. Second, the SEM latent vectors were spatially mapped using random forests regressions with UAV-based hyperspectral and structural information. Finally, this enabled us to map belowground C stocks using the SEM functions parameterized with the random forests derived maps. This SEM approach resulted in higher accuracies than a direct application of a purely data-driven random forests approach with UAV data, with improvements of r2 from 0.39 to 0.54, normalized RMSE from 31.33% to 20.24% and bias from −0.73 to 0.05. Our case study showed that: (1) vegetation height, species richness and aboveground biomass are good proxies to map peatland belowground C stocks, as they can be estimated using remote sensing data and hold strong relationships with the belowground C gradient; and (2) SEM is facilitates to incorporate theoretical knowledge in empirical modeling approaches. | |
| Spiky fluctuations and scaling in high-resolution EPICA ice core dust fluxes | Climate of the Past | Lovejoy, S.; Lambert, F. | 2019 | Ciudades Resilientes | 10.5194/cp-15-1999-2019 | https://www.clim-past.net/15/1999/2019/ | 1999-2017 | Vol: 15 Issue: 6 | 1814-9332 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Atmospheric variability as a function of scale has been divided in various dynamical regimes with alternating increasing and decreasing fluctuations: weather, macroweather, climate, macroclimate, and megaclimate. Although a vast amount of data are available at small scales, the larger picture is not well constrained due to the scarcity and low resolution of long paleoclimatic time series. Using statistical techniques originally developed for the study of turbulence, we analyse the fluctuations of a centimetric-resolution dust flux time series from the EPICA Dome C ice core in Antarctica that spans the past 800 000 years. The temporal resolution ranges from annual at the top of the core to 25 years at the bottom, enabling the detailed statistical analysis and comparison of eight glaciation cycles and the subdivision of each cycle into eight consecutive phases. The unique span and resolution of the dataset allows us to analyse the macroweather and climate scales in detail. We find that the interglacial and glacial maximum phases of each cycle showed particularly large macroweather to climate transition scale τc (around 2 kyr), whereas mid-glacial phases feature centennial transition scales (average of 300 years). This suggests that interglacials and glacial maxima are exceptionally stable when compared with the rest of a glacial cycle. The Holocene (with τc≈7.9 kyr) had a particularly large τc, but it was not an outlier when compared with the phases 1 and 2 of other cycles. We hypothesize that dust variability at larger (climate) scales appears to be predominantly driven by slow changes in glaciers and vegetation cover, whereas at small (macroweather) scales atmospheric processes and changes in the hydrological cycles are the main drivers. For each phase, we quantified the drift, intermittency, amplitude, and extremeness of the variability. Phases close to the interglacials (1, 2, 8) show low drift, moderate intermittency, and strong extremes, while the “glacial” middle phases 3–7 display strong drift, weak intermittency, and weaker extremes. In other words, our results suggest that glacial maxima, interglacials, and glacial inceptions were characterized by relatively stable atmospheric conditions but punctuated by frequent and severe droughts, whereas the mid-glacial climate was inherently more unstable. |
| Integrating socio-ecological dynamics into land use policy outcomes: A spatial scenario approach for native forest conservation in south-central Chile | Land Use Policy | Manuschevich, D.; Sarricolea, P.; Galleguillos, M. | 2019 | Cambio de Uso de Suelo | 10.1016/j.landusepol.2019.01.042 | https://linkinghub.elsevier.com/retrieve/pii/S0264837718307518 | 31-42 | Vol: 84 | 0264-8377 | Thomson Reuters ISI (SSCI) | English | Chile is one of the first documented nations to undergo a forest transition dominated by tree farm expansion. Scenario modelling can inform the possible outcomes of forest conservation policies, especially when the scenarios are rooted in the political dynamics that shaped the current legislation. In Chile, tree farms of non-native Radiata Pine and Eucalyptus provide a fast return on investment. Today, fast-growing plantations compete for land area with forest conservation, putting the unique bundle of ecosystem services provided by the latter at risk. Based on a previous political analysis, we propose scenarios projected to 2030 to compare a business-as-usual scenario with A) a conservation scenario based on strict land use restrictions B) an optimistic conservation scenario; C) an unrestricted industrial land use scenario; and D) a restricted industrial land use scenario. The scenarios differ in terms of the implemented policy instruments and the land area required for each land use. We compared these scenarios in terms of carbon stock, control of erosion and wood production, all of which are relevant in the current Chilean political debate. A conservation scenario (A), that combines incentives and restrictions, would imply the largest increase in native forest and regulation services, namely carbon stock and erosion control. In contrast, an unrestricted industrial land use scenario (C) leads to the worst outcomes in terms of erosion compared to a business-as-usual scenario. This study seeks to link political and economic processes underpinning land use change to environmental outcomes, while contributing to the larger discussion on forest policy, forest transitions and environmental outcomes. © 2019 | |
| Comité Científico COP25: Biodiversidad Capítulo 5 Cambio de uso del suelo en Chile: Oportunidades de mitigación ante la emergencia climática | Marquet, P.; Lara, A.; Altamirano, A.; Alaniz, C.; Álvarez, M.; Castillo, M.; Galleguillos, M.; Grez, A.; Gutiérrez, A.; Hoyos-Santillan, J.; Manuschevich, R.; Garay, M.; Miranda, A.; Ostria, E.; Peña-Cortéz, J.; Pérez-Quezada, J.; Sepúlveda, A.; Simonetti, J.; Smith, C. | 2019 | Cambio de Uso de Suelo | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-biodiversidad/9.Biodiversidad-CUS-Lara.pdf | Spanish | ||||||||
| Ventilation of the Deep Ocean Carbon Reservoir During the Last Deglaciation: Results From the Southeast Pacific | Paleoceanography and Paleoclimatology | Martínez Fontaine, C.; De Pol‐Holz, R.; Michel, E.; Siani, G.; Reyes‐Macaya, D.; Martínez‐Méndez, G.; DeVries, T.; Stott, L.; Southon, J.; Mohtadi, M.; Hebbeln, D. | 2019 | Cambio de Uso de Suelo | 10.1029/2019PA003613 | https://onlinelibrary.wiley.com/doi/abs/10.1029/2019PA003613 | 2080-2097 | Vol: 34 Issue: 12 | 2572-4517 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Coeval changes in atmospheric CO2 and 14C contents during the last deglaciation are often attributed to ocean circulation changes that released carbon stored in the deep ocean during the Last Glacial Maximum (LGM). Work is being done to generate records that allow for the identification of the exact mechanisms leading to the accumulation and release of carbon from the oceanic reservoir, but these mechanisms are still the subject of debate. Here we present foraminifera 14C data from five cores in a transect across the Chilean continental margin between ~540 and ~3,100 m depth spanning the last 20,000 years. Our data reveal that during the LGM, waters at ~2,000 m were 50% to 80% more depleted in Δ14C than waters at ~1,500 m when compared to modern values, consistent with the hypothesis of a glacial deep ocean carbon reservoir that was isolated from the atmosphere. During the deglaciation, our intermediate water records reveal homogenization in the Δ14C values between ~800 and ~1,500 m from ~16.5–14.5 ka cal BP to ~14–12 ka cal BP, which we interpret as deeper penetration of Antarctic Intermediate Water. While many questions still remain, this process could aid the ventilation of the deep ocean at the beginning of the deglaciation, contributing to the observed ~40 ppm rise in atmospheric pCO2. ©2019. American Geophysical Union. All Rights Reserved. |
| Streamflow variations across the Andes (18°–55°S) during the instrumental era | Scientific Reports | Masiokas, M.; Cara, L.; Villalba, R.; Pitte, P.; Luckman, B.; Toum, E.; Christie, D.; Le Quesne, C.; Mauget, S. | 2019 | Agua y Extremos | 10.1038/s41598-019-53981-x | http://www.nature.com/articles/s41598-019-53981-x | 17879 | Vol: 9 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The rivers originating in the southern Andes (18°–55°S) support numerous ecosystems and a large number of human populations and socio-economic activities in the adjacent lowlands of Chile, Argentina and Bolivia. Here we show that ca. 75% of the total variance in the streamflow records from this extensive region can be explained by only eight spatially coherent patterns of variability. Five (three) of these Andean patterns exhibit extreme dry (wet) conditions in recent years, with strong interannual variations in northern Chile; long-term drying trends between 31° and 41°S; a transitional pattern in the central Patagonian Andes; and increasing trends in northwestern Argentina and southern Bolivia, the Fueguian Andes, and the eastern portion of the South Patagonian Icefield. Multivariate regression analyses show that large-scale indices of ENSO variability can predict 20% to 45% of annual runoff variability between 28° and 46°S. The influence of Antarctic and North Pacific indices becomes more relevant south of 43°S and in northwestern Argentina and southern Bolivia, respectively, but their overall skill as predictors of Andean streamflows is weak. The analyses provide relevant new information to improve understanding of the spatial coherence, the main temporal features, and the ocean-atmospheric forcings of surface runoff across the southern Andes. |
| Livelihood trajectories in the Chilean Patagonian region: an ethnographic approach to coastal and marine socioecological change | Regional Environmental Change | Mellado, M.; Blanco-Wells, G.; Nahuelhual, L.; Saavedra, G. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.1007/s10113-018-1398-3 | http://link.springer.com/10.1007/s10113-018-1398-3 | 205-217 | Vol: 19 Issue: 1 | 1436-3798, 1436-378X | Thomson Reuters ISI (SCIE; SSCI) | English | Livelihood trajectories are a conceptual device to synthetize the collection of successive strategies displayed by individuals and groups to ensure survival and wellbeing over time. Using this concept, we conduct an explorative analysis of how various episodes, interventions, and ecological change have influenced different livelihood strategies of small-scale fishermen in the southernmost region of the world, the Patagonian region of Magallanes, Chile. Through ethnographic research, we identified four trajectories along five distinct periods: (i) 1960–1972, from the year of the largest recorded earthquake in world history to the initial expansion of industrial fishing; (ii) 1973–1982, from the military coup and the beginning of neoliberal reforms; (iii) 1983–1990, marked by fishing export booms; (iv) 1991–2000, noted by return to democracy and enactment of the first Fishing and Aquaculture General Act; and (v) 2000 to present, characterized by coastal planning and changes to the aforementioned law. Along these periods, trajectories are marked by migration waves and the deployment of specific livelihood strategies, highly modulated by both global seafood markets and legal changes. The results show the potential of ethnographic approaches to the study of long-term interactions in marine and coastal socioecological systems by identifying underlying historical dynamics, specific pulses and pressures, and actors’ responses to regional socioecological changes. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature. | |
| Marine Radiocarbon Reservoir Age Along the Chilean Continental Margin | Radiocarbon | Merino-Campos, V.; De Pol-Holz, R.; Southon, J.; Latorre, C.; Collado-Fabbri, S. | 2019 | Cambio de Uso de Suelo | 10.1017/RDC.2018.81 | https://www.cambridge.org/core/product/identifier/S0033822218000814/type/journal_article | 195-210 | Vol: 61 Issue: 1 | 0033-8222 | Thomson Reuters ISI (SCIE) | English | We present 37 new radiocarbon (14C) measurements from mollusk shells fragments sampled along the Chilean continental margin and stored in museum collections with known calendar age. These measurements were used to estimate the modern pre-bomb regional marine 14C age deviations from the global ocean reservoir (∆R). Together with previously published data, we calculated regional mean ∆R values for five oceanographic macro regions along the coast plus one for a mid-latitude open ocean setting. In general, upwelling regions north of 42ºS show consistent although sometimes highly variable ∆R values with regional averages ranging from 141 to 196 14C yr, whereas the mid-latitude open ocean location of the Juan Fernández archipelago and the southern Patagonian region show minor, ∆R of 40±38 14C yr, and 52±47 14C yr respectively. We attribute the alongshore decreasing pattern toward higher latitudes to the main oceanographic features along the Chilean coast such as perennial coastal upwelling in northern zone, seasonally variable upwelling at the central part and the large freshwater influence upon the southern | |
| Traits of perch trees promote seed dispersal of endemic fleshy-fruit species in degraded areas of endangered Mediterranean ecosystems | Journal of Arid Environments | Miranda, A.; Vásquez, I.; Becerra, P.; Smith-Ramírez, C.; Delpiano, C.; Hernández-Moreno, A.; Altamirano, A. | 2019 | Cambio de Uso de Suelo | 10.1016/j.jaridenv.2019.103995 | https://linkinghub.elsevier.com/retrieve/pii/S0140196319300862 | 103995 | Vol: 170 | 0140-1963 | Thomson Reuters ISI (SCIE) | English | The presence and attributes of perch trees in degraded areas may promote seed dispersal. We evaluated the effect of the distance from remnant forest fragments on seed rain of different fleshy-fruit tree species and examined whether the seed rain is favoured by some traits of the perch trees (Acacia caven), such as canopy diameter and tree height. The study was carried out in two localities of central Chile with extensive “espinales” adjacent to remnant fragments of sclerophyllous forest. We installed 210 seed traps under the same number of A. caven trees along 10 transects in the two study areas. We set up the seed traps between 1 and 100 m away from forest fragments. We found a significant negative relationship between seed rain and distance. We also found a positive relationship between seed rain and the height and canopy diameter of the perch tree. Our results suggest that different woody species are able to disperse into the espinal, and that bigger A. caven trees are better perches than smaller individuals. We propose that at distances up to at least 100 m from forest fragments, seed availability does not limit natural regeneration into espinales. | |
| Sentencia de la Corte Suprema de 24 de diciembre de 2018: Riesgo y precaución | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2019 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-riesgo-principio-de-precaucion/ | 1989-5666 | ESCI | ||||||
| Sentencia Tribunal Ambiental de Santiago: Contaminación del aire, acceso a la información y prevención | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2019 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-contaminacion-del-aire-acceso-a-la-informacion/ | 1989-5666 | ESCI | ||||||
| Sentencia Tribunal Ambiental de Santiago de 8 de febrero de 2019: participación, consulta indígena y cambio climático | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2019 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-mineria-participacion/ | 1989-5666 | ESCI | ||||||
| Sentencia Segundo Tribunal Ambiental de Santiago “Sepúlveda Silva Sebastián y otro/ Superintendencia del Medio Ambiente, de 22 de julio de 2019 | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2019 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-bosques-evaluacion-de-impacto-ambiental/ | 1989-5666 | ESCI | ||||||
| Sentencia Corte Suprema “Fundación Jorge Yarur Bascuñán vs Sociedad Urbanizadora Reñaca Concón”, de 5 de junio de 2019 | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2019 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-evaluacion-de-impacto-ambiental-urbanismo-espacios-protegidos/ | 1989-5666 | ESCI | ||||||
| Sentencia Tribunal Ambiental de Santiago: medidas provisionales pre-procedimentales, consulta de pertinencia, institucionalidad ambiental | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Spoerer Rodrik, K. | 2019 | Gobernanza e Interfaz Ciencia y Política | https://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-evaluacion-de-impacto-ambiental-2/ | 1989-5666 | ESCI | ||||||
| La compleja definición del problema socioambiental: racionalidades y controversias | Revista Mad | Morales, B.; Aliste, E.; Neira, C.; Urquiza, A. | 2019 | Ciudades Resilientes | 10.5354/0719-0527.2019.54834 | https://doi.org/10.5354/0719-0527.2019.54834 | 43-51 | Vol: 40 | 0718-0527 | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access; Green Open Access | Spanish | Drawing from a qualitative approach, this article addresses some of the elements that allow thematizing the socioenvironmental problem from its own complexity, and considering the point of view of different actors, which are part of this discussion in the Chilean context, and giving special emphasis on the controversies generated around the terms “development” and “sustainability.” First, we address the elements – theoretical and empirical – that allow thematizing the complexity of the socioenvironmental problem. Second, we discuss a number of definitions given to “development” and their link to the origins of the problem. Third, we present options proposed by actors to move towards sustainability. The article concludes with reflections oriented to multiple perspectives about this issue. |
| A late Pleistocene human footprint from the Pilauco archaeological site, northern Patagonia, Chile | PLOS ONE | Moreno, K.; Bostelmann, J.; Macías, C.; Navarro-Harris, X.; De Pol-Holz, R.; Pino, M. | 2019 | Cambio de Uso de Suelo | 10.1371/journal.pone.0213572 | http://dx.plos.org/10.1371/journal.pone.0213572 | e0213572 | Vol: 14 Issue: 4 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | The present study describes the discovery of a singular sedimentary structure corresponding to an ichnite that was excavated at the paleo-archaeological site Pilauco (Osorno, Chile). The trace fossil is associated with megafauna bones, plant material and unifacial lithic tools. Here we present a detailed analysis of the Pilauco ichnite and associated sedimentary structures, as well as new radiocarbon data. The ichnological analysis confidently assigns the trace to the ichnospecies Hominipes modernus—a hominoid footprint usually related to Homo sapiens. Some particular characteristics of the Pilauco trace include an elongated distal hallux, lateral digit impressions obliterated by the collapsed sediment, and sediment lumps inside and around the trace. In order to evaluate the origin of the ichnite, trackmaking experiments are performed on re-hydrated fossil bed sediments. The results demonstrate that a human agent could easily generate a footprint morphology equivalent to the sedimentary structure when walking on a saturated substrate. Based on the evidence, we conclude that the trackmaker might well have been a bare-footed adult human. This finding, along with the presence of lithic artifacts in the same sedimentary levels, might represent further evidence for a pre-Clovis South American colonization of northern Patagonia, as originally proposed for the nearby Monte Verde site. |
| Early arboreal colonization, postglacial resilience of deciduous Nothofagus forests, and the Southern Westerly Wind influence in central-east Andean Patagonia | Quaternary Science Reviews | Moreno, P.; Simi, E.; Villa-Martínez, R.; Vilanova, I. | 2019 | Agua y Extremos | 10.1016/j.quascirev.2019.06.004 | https://linkinghub.elsevier.com/retrieve/pii/S0277379119301222 | 61-74 | Vol: 218 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | The history and dynamics of deciduous Nothofagus forests along the eastern slopes of the central Patagonian Andes (44°-49°S) remain insufficiently studied and understood, particularly at timescales ranging from centuries to millennia. Available fossil pollen records point to time-transgressive responses of the arboreal vegetation to climatic changes during the Last Glacial Termination (T1) and early Holocene, and spatial heterogeneity since then along north-south, east-west, and elevation transects. The degree to which these results represent biogeographic and climatic trends, varying environmental gradients, or site-specific phenomena has not been assessed in detail. Here we present a fossil pollen and macroscopic charcoal record from Lago Churrasco (45°41′S, 71°49′W), a small closed-basin lake located in the deciduous Nothofagus forest zone of the central-east Andes of Chilean Patagonia. Our results suggest that Nothofagus trees colonized newly deglaciated terrains at ∼16,000 cal yr BP and formed scrublands/woodlands several millennia earlier than reported by previous studies east of the Andes. This suggests expansion and local densification of tree populations sourced from the eastern margin of the Patagonian Ice Sheet during the Last Glacial Maximum, with the additional implication that temperature and precipitation conditions favorable for tree survival and reproduction developed early during T1. We posit that the amount of moisture delivered by the Southern Westerly Winds was not a limiting factor for arboreal expansion during T1 in this sector of the central Patagonian Andes. Closed-canopy Nothofagus forests established at ∼10,000 cal yr BP and have remained essentially invariant despite climate change and natural disturbance regimes. This resilience was challenged and exceeded by human disturbance during the 20th century through the use of fire, leading to deforestation and spread of invasive exotic species in an extraordinarily rapid event. Our record suggests a permanent influence of the Southern Westerly Winds over the last 10,000 years, with relatively modest variations at centennial and millennial timescales. | |
| Comité Científico COP25: Transformation from science to decision making | Moser, S.; Aldunce, P.; Rudnick, A.; Rojas, M.; Muñoz, L. | 2019 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-adaptacion/4.Adaptation-Transformation-Policy-Brief.pdf | The IPCC2 understands Transformations as systemic changes that enable more ambitious, i.e., significant and rapid, advances in mitigation and adaptation than currently being observed, while also pursuing the Sustainable Development Goals of Agenda 2030. While challenging, deep and difficult transformational change is seen as an opportunity to improve human and natural conditions. Mitigation, adaptation and sustainability should thus be seen as complementary, not competing goals. Transformation means going beyond the familiar in policy- and decision-making, with actors in all sectors focused on shifting the conditions that hold damaging systems in place. | ||||||||
| Comité Científico COP25: Transformación desde la ciencia a la toma de decisiones | Moser, S.; Aldunce, P.; Rudnick, A.; Rojas, M.; Muñoz, L. | 2019 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-adaptacion/3.Adaptacion-Transformacion-Resumen-de-politicas.pdf | El IPCC2 entiende por transformación aquellos cambios sistémicos que permiten avances más ambiciosos en mitigación y adaptación, es decir, significativos y rápidos, más allá de lo observado en la actualidad, y que al mismo tiempo persigan los Objetivos de Desarrollo Sostenible (ODS) de la Agenda 2030. Si bien los cambios transformadores pueden ser desafiantes, profundos y difíciles, también constituyen una oportunidad para mejorar las condiciones de la sociedad y de la naturaleza. La mitigación, la adaptación y la transformación no deben considerarse como enfoques competitivos, sino como complementarios. La transformación significa ir más allá de lo que se ha hecho hasta ahora en la política y toma de decisiones. Para lograrlo, se requieren actores de todos los sectores, enfocados en cambiar las condiciones para mantener y mejorar los sistemas dañados | ||||||||
| Multidecadal environmental pollution in a mega-industrial area in central Chile registered by tree rings | Science of The Total Environment | Muñoz, A.; Klock-Barría, K.; Sheppard, P.; Aguilera-Betti, I.; Toledo-Guerrero, I.; Christie, D.; Gorena, T.; Gallardo, L.; González-Reyes, Á.; Lara, A.; Lambert, F.; Gayo, E.; Barraza, F.; Chávez, R. | 2019 | Agua y Extremos; Ciudades Resilientes | 10.1016/j.scitotenv.2019.133915 | https://linkinghub.elsevier.com/retrieve/pii/S0048969719338653 | 133915 | Vol: 696 | 0048-9697 | Thomson Reuters ISI (SCIE) | English | One of the most polluted areas in Chile is the Ventanas Industrial Area (VIA; 32.74°S / 71.48°W), which started in 1958 and today comprises around 16 industries in an area of ca. 4 km2. A lack of consistent long-term instrumental records precludes assessing the history of contamination in the area and also limits the evaluation of mitigation actions taken since the late 1980s. Here, we use dendrochemistry as an environmental proxy to analyze environmental changes over several decades at the VIA. We present chemical measurements of tree rings from planted, exotic Cupressus macrocarpa growing near the VIA with 4-year resolution over a period of 52 years (1960–2011). These data provide unprecedented information on regional anthropogenic pollution and are compared with a tree-ring elemental record of 48 years (1964–2011) from the Isla Negra (INE) control site not exposed to VIA emissions. For the 48 years of overlap between both sites, higher concentrations of Zn, V, Co, Cd, Ag, Fe, Cr, and Al were especially registered after the year 2000 at VIA compared to INE for the periods under study. Concentrations of Pb, Cu, As, Fe, Mo, Cr, and Zn increased through time, particularly over the period 1980–1990. Decontamination plans activated in 1992 appear to have had a positive effect on the amount of some elements, but the chemical concentration in the tree rings suggest continued accumulation of pollutants in the environment. Only after several years of implementation of the mitigation measures have some elements tended to decrease in concentration, especially at the end of the evaluated period. Dendrochemistry is a useful tool to provide a long-term perspective of the dynamics of trace metal pollution and represents a powerful approach to monitor air quality variability to extend the instrumental records back in time. | |
| Comité Científico COP25: Ciudades y cambio climático en Chile: Recomendaciones desde la evidencia científica | Muñoz, J.; Barton, J.; Frías, D.; Godoy, A.; Bustamante, W.; Cortés, S.; Munizaga, M.; Rojas, C.; Wagemann, E.; Smith, P.; Gallardo, L. | 2019 | Ciudades Resilientes | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-ciudades/Ciudades-y-CC-en-Chile-Recomendaciones-desde-evidencia-cientifica.pdf | En el marco de las preparaciones del Gobierno de Chile frente a la COP25, y como parte de las actividades del Comité Científico COP25 establecido por el Ministerio de Ciencia, Tecnología, Conocimiento e Innovación, este documento tiene tres propósitos. El primero es reunir información de varios documentos de política pública relacionados con ciudades y cambio climático en Chile. El segundo es destacar la situación urbana en Chile en relación con los temas de mitigación (movilidad; edificación, equipamiento y energía; residuos y economía circular), adaptación (riesgos y desastres; infraestructura y espacios verdes; vulnerabilidad y salud) y gobernanza. El tercero es presentar propuestas de acción en formato de fichas que pretenden contribuir a reducir las emisiones que surgen desde ciudades y reducir la vulnerabilidad en los asentamientos humanos en Chile frente al cambio climático. Estas propuestas se han estructurado en torno a metas, identificando instituciones que debieran participar de ellas, sugiriendo plazos posibles en que estas medidas podrían implementarse, caracterizando beneficios que estas medidas generarían y destacando evidencia científica que las avala. Dada la complejidad propia de la gobernanza urbana, estas medidas debieran considerarse en coordinación entre la sociedad civil, el sector público y el sector privado. La mesa Ciudades reúne los aportes de más de cincuenta académicos de diez universidades con el objeto de contribuir desde múltiples disciplinas a opciones de acción urbana frente a los desafíos del cambio climático. | ||||||||
| Is there a blue transition underway? | Fish and Fisheries | Nahuelhual, L.; Defeo, O.; Vergara, X.; Blanco, G.; Marín, S.; Bozzeda, F. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.1111/faf.12354 | https://doi.org/10.1111/faf.12354 | 584-595 | Vol: 20 Issue: 3 | 1467-2960 | Thomson Reuters ISI (SCIE) | English | In this study, we describe what we term a Blue Transition, defined as the passage from fish biomass reduction to recovery in exploited aquatic resources, enabled by aquaculture. A Blue Transition is a key component of emergent “blue” discourses which support that the expansion of aquaculture would relieve pressure on declining capture fisheries, thus contributing to global food security, particularly of the poorest populations. Based on global secondary data and the case of Chile, we explore the evidence of such claim and the implications of a Blue Transition for fisheries and aquaculture development. In 2012, worldwide aquaculture production surpassed wild captures; nevertheless, such turnaround would have not taken place without China's contribution. In Chile, this turnaround occurred in 2014, concurrently with the lowest industrial landings registered since the 1960s (1,227,359 tons). Chile's aquaculture is not relieving wild fisheries or satisfying food demands of the lower income population, in the country or elsewhere. Salmon, the main aquaculture product, is destined mainly to Japan, Russia and United States where, due to its high prices, it is consumed mostly by wealthy consumers. For the case at hand, evidence suggests that a blue transition may be underway but is going in the wrong direction: from what may have been sustainable fisheries management before the 1970s to the overexploited wild fisheries of today. © 2019 John Wiley & Sons Ltd | |
| Using probabilistic analysis to improve greenhouse gas baseline forecasts in developing country contexts: the case of Chile | Climate Policy | ORyan, R.; Benavides, C.; Díaz, M.; San Martín, J.; Mallea, J. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.1080/14693062.2018.1503153 | https://www.tandfonline.com/doi/full/10.1080/14693062.2018.1503153 | 299-314 | Vol: 19 Issue: 3 | 1469-3062, 1752-7457 | Thomson Reuters ISI (SSCI) | English | In this paper, initial steps are presented toward characterizing, quantifying, incorporating and communicating uncertainty applying a probabilistic analysis to countrywide emission baseline forecasts, using Chile as a case study. Most GHG emission forecasts used by regulators are based on bottom-up deterministic approaches. Uncertainty is usually incorporated through sensitivity analysis and/or use of different scenarios. However, much of the available information on uncertainty is not systematically included. The deterministic approach also gives a wide range of variation in values without a clear sense of probability of the expected emissions, making it difficult to establish both the mitigation contributions and the subsequent policy prescriptions for the future. To improve on this practice, we have systematically included uncertainty into a bottom-up approach, incorporating it in key variables that affect expected GHG emissions, using readily available information, and establishing expected baseline emissions trajectories rather than scenarios. The resulting emission trajectories make explicit the probability percentiles, reflecting uncertainties as well as possible using readily available information in a manner that is relevant to the decision making process. Additionally, for the case of Chile, contradictory deterministic results are eliminated, and it is shown that, whereas under a deterministic approach Chile’s mitigation ambition does not seem high, the probabilistic approach suggests this is not necessarily the case. It is concluded that using a probabilistic approach allows a better characterization of uncertainty using existing data and modelling capacities that are usually weak in developing country contexts. | |
| Extreme ENSO-driven torrential rainfalls at the southern edge of the Atacama Desert during the Late Holocene and their projection into the 21th century | Global and Planetary Change | Ortega, C.; Vargas, G.; Rojas, M.; Rutllant, J.; Muñoz, P.; Lange, C.; Pantoja, S.; Dezileau, L.; Ortlieb, L. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.gloplacha.2019.02.011 | https://linkinghub.elsevier.com/retrieve/pii/S0921818118304995 | 226-237 | Vol: 175 | 0921-8181 | Thomson Reuters ISI (SCIE) | English | Extreme precipitation events and multi-annual droughts, especially in arid to semi-arid subtropical regions, are among the most critical El Niño Southern Oscillation (ENSO) and global climate change impacts. Here, we assess the variability of torrential rainfall during the Late Holocene and its projection into the 21st century at the southern edge of the hyperarid Atacama Desert. The analysis of historical data since the beginning of the 20th century reveals that most (76.5%) alluvial disasters in the southern Atacama Desert (26–30°S) have resulted from extreme rainfall events occurring between March and September under El Niño conditions, and more frequently during the warm phase of the Pacific Decadal Oscillation. Particular rainfall events under these ocean-climate conditions are associated with the convective phase of the Madden-Julian Oscillation (MJO) near the central-equatorial Pacific, resulting in warmer sea surface temperature (SST) there and in the triggering of persistent/intense Pacific South America (PSA) tropical-extratropical teleconnection patterns which result in blocking of the westerly flow at high latitudes and the subsequent deviation of storm tracks towards central-northern Chile. On a longer timescale, marine sediments from Tongoy Bay (30°S) reveal an increasing trend of stronger runoff by torrential coastal rain since ca. 3500 cal yr BP and even stronger heavy rainfall since ca. 1700 cal yr BP. Highly variable coastal sea surface temperatures in the same time span deduced from the sedimentary record can be explained by intensified southerly winds in connection with stronger alongshore pressure gradients and reduced coastal low-cloud cover. Both storm intensification and increased intensity of upwelling-favorable winds point to a variable climate conditioned by strengthened interannual ENSO and interdecadal ENSO-like variability during the Late Holocene. Climate projections from the Coupled Model Intercomparison Project Phase 5 (CMIP5) indicate a reduction in annual precipitation of 15–30% during the current century, together with an intensification of the storms, such as the alluvial disaster on March 25, 2015 in Atacama. © 2019 Elsevier B.V. | |
| Comité Científico COP25: Chilean NDC mitigation proposal: Methodological approach and supporting ambition. Mitigation and energy working group report | Palma-Behnke, R.; Barría, C.; Basoa, K.; Benavente, D.; Benavides, C.; Campos, B.; de la Maza, N.; Farías, L.; Gallardo, L.; García, M.; Gonzales, L.; Guarda, F.; Guzmán, R.; Jofré, A.; Mager, J.; Martínez, R.; Montedonico, M.; Morán, L.; Muñoz, L.; Osses, M.; Pica, A.; Rojas, M.; Rudnick, A.; SanMa... | 2019 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://comitecientifico.minciencia.gob.cl/wp-content/uploads/2021/11/The_Chilean_Potential_for_Exporting_Renewable_Energy_web.pdf | This paper analyses the Chilean Nationally Determined Contributions (NDC) proposal for the mitigation component. The methodological approach and the supporting ambition of a process carried out by the Chilean Government are assessed based on the scientific evidence available and local context. The analysis is developed by representatives of four ministries and a group of 21 researchers from six universities and research centers throughout the country. This exchange experience between the Government and the scientific community enables the identification of future challenges and opportunities for the Chilean transition in terms of mitigation. This process emerges from a bridging approach led by the recently assumed Minister of Science, Technology, Knowledge and Innovation under the presidency of the Government of Chile in the Conference of the Parties (COP25) for the United Nations Framework Convention on Climate Change (UNFCCC). After a description of the methodological approach, key topics that have an impact on the NDC definition are identified and analyzed. These topics include technical, economical, and socio-environmental issues along with a description of the current socio-political context in the country. Additionally, the major uncertainties that would have the highest potential to modify the results and conclusions of this work are identified. Finally, a summary with the main conclusions and recommendations is presented. The analysis framework and key aspects identified in this exercise may be of value for other countries with similar institutional contexts. | ||||||||
| Beyond inputs and outputs: Process‐oriented explanation of institutional change in climate adaptation governance | Environmental Policy and Governance | Patterson, J.; Voogt, D.; Sapiains, R. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.1002/eet.1865 | https://onlinelibrary.wiley.com/doi/abs/10.1002/eet.1865 | 360-375 | Vol: 29 Issue: 5 | 1756-932X | Thomson Reuters ISI (SSCI) | All Open Access; Green Open Access; Hybrid Gold Open Access | English | Climate adaptation is a growing imperative across all scales and sectors of governance. This often requires changes in institutions, which can be difficult to realize. Explicitly process‐oriented approaches explaining how and why institutional change occurs are lacking. Overcoming this gap is vital to move beyond either input‐oriented (e.g., capacity) or output‐oriented (e.g., assessment) approaches, to understand how changes actually occur for addressing complex and contested governance issues. This paper analyses causal conditions and mechanisms by which institutions develop in climate adaptation governance. It focuses on urban climate governance through an in‐depth case study of Santiago, Chile, over a 12‐year period (2005–2017), drawing on primary and secondary data, including 26 semistructured interviews with policy, academic, and civil society actors. It identifies and explains a variety of institutional developments across multiple levels (i.e., programmatic, legislative, and constitutional), through a theory‐centric process tracing methodology. This reveals a multiple‐response pattern, involving several causal mechanisms and coexisting institutional logics. Findings suggest that although adaptation may be inherently protracted, institutions can nevertheless develop in both related and novel directions. Overall, the paper argues for a new research agenda on process‐oriented theorizing and analysis in climate and environmental governance. |
| Rare calcium chloride–rich soil and implications for the existence of liquid water in a hyperarid environment | Geology | Pfeiffer, M.; Latorre, C.; Gayo, E.; Amundson, R. | 2019 | Ciudades Resilientes | 10.1130/G45642.1 | https://pubs.geoscienceworld.org/gsa/geology/article/47/2/163/568106/Rare-calcium-chloriderich-soil-and-implications | 163-166 | Vol: 47 Issue: 2 | 0091-7613 | Thomson Reuters ISI (SCIE) | English | We discovered permanently hydrated CaCl2-rich soils in Earth’s driest region, the Atacama Desert. The soils contain up to ∼15% CaCl2. X-ray diffraction indicates the rare minerals sinjarite, schoenite, and tachyhydrite. When water is added, the CaCl2 crust immediately turns white due to an apparent mineralogical phase change from sinjarite to a brine. The surfaces are nearly continuously wet due to the salt’s hygroscopicity. The Ca-enriched soils occur in rare exposures, possibly from shallow groundwater. Unlike the surface of adjacent abundant halite crusts, the CaCl2 outcrops remain continuously wet, with up to 12% water under modern, and essentially rainless, climatic conditions. The wet surface stabilizes the land surface and acts as a dust trap. The sediment began accumulating at ca. 14 ka, contains trace quantities of organic carbon, and has total nitrogen that isotopically reflects significant biologically mediated gaseous losses. These deliquescent salts are unique habitats for life within the climatic limits of life on Earth, and are a potential analog for transient liquid-water sources for microorganisms in Martian soils. | |
| 2018 International Atmospheric Rivers Conference: Multi‐disciplinary studies and high‐impact applications of atmospheric rivers | Atmospheric Science Letters | Ramos, A.; Wilson, A.; DeFlorio, M.; Warner, M.; Barnes, E.; Garreaud, R.; Gorodetskaya, I.; Lavers, D.; Moore, B.; Payne, A.; Smallcomb, C.; Sodemann, H.; Wehner, M.; Ralph, F. | 2019 | Agua y Extremos | 10.1002/asl.935 | https://onlinelibrary.wiley.com/doi/abs/10.1002/asl.935 | art: e935 | Vol: 20 Issue: 9 | 1530-261X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Atmospheric rivers (ARs) play a vital role in shaping the hydroclimate of many regions globally, and can substantially impact water resource management, emergency response planning, and other socioeconomic entities. The second International Atmospheric Rivers Conference took place at the Scripps Institution of Oceanography, University of California, San Diego, during 25–28 June, 2018, in La Jolla, California, USA. It was sponsored by the Center for Western Weather and Water Extremes (CW3E). A total of 120 people attended the Conference with 94 abstracts submitted and 30 participating students. In addition to the conference, the Student Forecasting Workshop was organised in the same week. During this workshop, students were exposed to AR forecasting tools, and learned examples of how these tools could be used to make decisions for various applications. The main goals of this conference were to bring together experts from across the fields of hydrology, atmospheric, oceanic, and polar sciences, as well as water management, civil engineering, and ecology to advance the state of AR science and to explore the future directions for the field. The conference was organised into traditional oral and poster presentations, along with panel discussions and Breakout Groups. This format allowed enhanced interaction between participants, driving progress within the scientific community and the enhanced communication of societal needs by various stakeholders. Several emerging topics of research were highlighted, including subseasonal‐to‐seasonal (S2S) prediction of ARs and an overview of the AR Reconnaissance campaign. In addition to providing a forum to disseminate and debate new results from scientific talks and posters, the conference was equally effective and useful in linking scientists to users and decision‐makers that require improved knowledge on ARs to manage resources and prepare for hazards. The third International Atmospheric Rivers Conference will be held in Chile in 2020, and hosted by the University of Chile, Santiago. |
| Holocene glacier fluctuations in Patagonia are modulated by summer insolation intensity and paced by Southern Annular Mode-like variability | Quaternary Science Reviews | Reynhout, S.; Sagredo, E.; Kaplan, M.; Aravena, J.; Martini, M.; Moreno, P.; Rojas, M.; Schwartz, R.; Schaefer, J. | 2019 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.1016/j.quascirev.2019.05.029 | https://linkinghub.elsevier.com/retrieve/pii/S0277379119300745 | 178-187 | Vol: 220 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | Alpine glaciers are sensitive indicators of changes in climate, and their ubiquity in mountainous regions make them valuable proxies for terrestrial climate reconstructions worldwide. However, the timing and extent of glacier change across the South American mid-latitudes through the Holocene are still poorly constrained relative to their counterparts in the Northern Hemisphere. Here we report a new 10Be surface exposure-based chronology of moraines recording a series of progressively less-extensive glacier advances of Glaciar Torre (Argentina, 49.3°S/73.0°W) since the Last Glacial Maximum, with expansions culminating at 17,600 ± 900, 13,500 ± 500, 9700 ± 400, 6900 ± 200, 6100 ± 300, 4500 ± 200, and 530 ± 60 yr BP. The declining magnitude of Holocene glacier expansions parallels a gradual rise in local summer insolation intensity during the Holocene, while individual advances occurred during inferred negative Southern Annular Mode (SAM)-like states at centennial to millennial timescales. These observations suggest that (i) summer insolation intensity modulated antiphased trends in glacier extent in the polar hemispheres during the Holocene, and that (ii) centennial-scale ‘SAM-like’ temperature and precipitation anomalies paced glacier fluctuations throughout Patagonia. Given the persistence of the inferred ’SAM-like’ anomalies throughout the Holocene, the modern measured trend towards positive SAM index conditions could mark the onset of a fundamental shift in the climate of the Southern Hemisphere midlatitudes that warrants consideration in projections of future climate. | |
| Validation of Cryogenic Vacuum Extraction of Pore Water from Volcanic Soils for Isotopic Analysis | Water | Rivera, D.; Gutierrez, K.; Valdivia-Cea, W.; Zambrano-Bigiarini, M.; Godoy-Faúndez, A.; Álvez, A.; Farías, L. | 2019 | Agua y Extremos; Zonas Costeras | 10.3390/w11112214 | https://www.mdpi.com/2073-4441/11/11/2214 | 2214 | Vol: 11 Issue: 11 | 2073-4441 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Andean headwater catchments are key components of the hydrological cycle, given that they capture moisture, store water and release it for Chilean cities, industry, agriculture, and cities in Chile. However, knowledge about within-Andean catchment processes is far from clear. Most soils in the Andes derive from volcanic ash Andosols and Arenosols presenting high organic matter, high-water retention capacity and fine pores; and are very dry during summer. Despite their importance, there is little research on the hillslope hydrology of Andosols. Environmental isotopes such as Deuterium and 18-O are direct tracers for water and useful on analyzing water-soil interactions. This work explores, for the first time, the efficiency of cryogenic vacuum extraction to remove water from two contrasting soil types (Arenosols, Andosols) at five soil water retention energies (from −1500 to −33 kPa). Two experiments were carried out to analyse the impact of extraction time, and initial water content on the amount of extracted water, while a third experiment tested whether the cryogenic vacuum extraction changed the isotopic ratios after extraction. Minimum extraction times to recover over 90% of water initially in the soil samples were 40–50 min and varied with soil texture. Minimum volume for very dry soils were 0.2 mL (loamy sand) and 1 mL (loam). After extraction, the difference between the isotope standard and the isotopic values after extraction was acceptable. Thus, we recommend this procedure for soils derived from volcanic ashes. |
| Comité Científico COP25: Evidencia científica y cambio climático en Chile. Resumen para tomadores de decisiones. | Rojas, M.; Aldunce, P.; Farías, L.; González, H.; Marquet, P.; Muñoz, J.; Palma-Behnke, R.; Stehr, A.; Vicuña, S. | 2019 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://comitecientifico.minciencia.gob.cl/wp-content/uploads/2021/05/Evidencia-cientifica-y-cambio-climatico-en-Chile-Resumen.pdf | 1-68 | Spanish | Los resúmenes están basados en los informes y los talleres del Comité Científico COP25, a los que contribuyeron investigadores de una red de más de 600 científicos de todas las disciplinas y regiones de Chile, primordialmente de universidades y centros de investigación académicos, pero también de institutos públicos y privados. |
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| Emergence of robust precipitation changes across crop production areas in the 21st century | Proceedings of the National Academy of Sciences | Rojas, M.; Lambert, F.; Ramirez-Villegas, J.; Challinor, A. | 2019 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1073/pnas.1811463116 | http://www.pnas.org/lookup/doi/10.1073/pnas.1811463116 | 6673-6678 | Vol: 116 Issue: 14 | 0027-8424 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | A warming climate will affect regional precipitation and hence food supply. However, only a few regions around the world are currently undergoing precipitation changes that can be attributed to climate change. Knowing when such changes are projected to emerge outside natural variability—the time of emergence (TOE)—is critical for taking effective adaptation measures. Using ensemble climate projections, we determine the TOE of regional precipitation changes globally and in particular for the growing areas of four major crops. We find relatively early (<2040) emergence of precipitation trends for all four crops. Reduced (increased) precipitation trends encompass 1–14% (3–31%) of global production of maize, wheat, rice, and soybean. Comparing results for RCP8.5 and RCP2.6 clearly shows that emissions compatible with the Paris Agreement result in far less cropped land experiencing novel climates. However, the existence of a TOE, even under the lowest emission scenario, and a small probability for early emergence emphasize the urgent need for adaptation measures. We also show how both the urgency of adaptation and the extent of mitigation vary geographically. |
| Strongest MJO on Record Triggers Extreme Atacama Rainfall and Warmth in Antarctica | Geophysical Research Letters | Rondanelli, R.; Hatchett, B.; Rutllant, J.; Bozkurt, D.; Garreaud, R. | 2019 | Agua y Extremos; Zonas Costeras | 10.1029/2018GL081475 | https://onlinelibrary.wiley.com/doi/abs/10.1029/2018GL081475 | 3482-3491 | Vol: 46 Issue: 6 | 0094-8276 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Tropical perturbations have been shown theoretically and observationally to excite long range atmospheric responses in the form of Rossby wave teleconnections that result from the equator to pole gradient of planetary vorticity. An extreme teleconnection event occurred during March 2015 in the Southeastern Pacific. As a result, extreme high temperatures were observed in Southwestern South America and the Antarctic Peninsula simultaneously with an extreme rainfall and flood event in the hyperarid Atacama desert.%%%%%%We show that the origin of these seemingly disconnected extreme events can be traced to a Rossby wave response to the strongest Madden‐Julian Oscillation (MJO) on record in the tropical central Pacific. A barotropic wavenumber 3 to 4 perturbation with group velocity between 15 to 30 m/s is consistent with the trajectory and timing followed by the upper level anomalies radiating away from the tropics after the MJO episode. |
| Black carbon and other light-absorbing impurities in snow in the Chilean Andes | Scientific Reports | Rowe, P.; Cordero, R.; Warren, S.; Stewart, E.; Doherty, S.; Pankow, A.; Schrempf, M.; Casassa, G.; Carrasco, J.; Pizarro, J.; MacDonell, S.; Damiani, A.; Lambert, F.; Rondanelli, R.; Huneeus, N.; Fernandoy, F.; Neshyba, S. | 2019 | Ciudades Resilientes; Zonas Costeras | 10.1038/s41598-019-39312-0 | http://www.nature.com/articles/s41598-019-39312-0 | art: 4008 | Vol: 9 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Vertical profiles of black carbon (BC) and other light-absorbing impurities were measured in seasonal snow and permanent snowfields in the Chilean Andes during Austral winters 2015 and 2016, at 22 sites between latitudes 18°S and 41°S. The samples were analyzed for spectrally-resolved visible light absorption. For surface snow, the average mass mixing ratio of BC was 15 ng/g in northern Chile (18–33°S), 28 ng/g near Santiago (a major city near latitude 33°S, where urban pollution plays a significant role), and 13 ng/g in southern Chile (33–41°S). The regional average vertically-integrated loading of BC was 207 µg/m 2 in the north, 780 µg/m 2 near Santiago, and 2500 µg/m 2 in the south, where the snow season was longer and the snow was deeper. For samples collected at locations where there had been no new snowfall for a week or more, the BC concentration in surface snow was high (~10–100 ng/g) and the sub-surface snow was comparatively clean, indicating the dominance of dry deposition of BC. Mean albedo reductions due to light-absorbing impurities were 0.0150, 0.0160, and 0.0077 for snow grain radii of 100 µm for northern Chile, the region near Santiago, and southern Chile; respective mean radiative forcings for the winter months were 2.8, 1.4, and 0.6 W/m 2 . In northern Chile, our measurements indicate that light-absorption by impurities in snow was dominated by dust rather than BC. © 2019, The Author(s). |
| Glacier decline in the Central Andes (33°S): Context and magnitude from satellite and historical data | Journal of South American Earth Sciences | Ruiz Pereira, S.; Veettil, B. | 2019 | Ciudades Resilientes | 10.1016/j.jsames.2019.102249 | https://linkinghub.elsevier.com/retrieve/pii/S0895981119301026 | 102249 | Vol: 94 | 0895-9811 | Thomson Reuters ISI (SCIE) | English | Central Andes (33°S) represent a water-scarce region. During arid years, glacier runoffmay constitute the mainhydrological input at warm season and hence a steadfast deglacierization may represent a decrease in the re-gional water-budget. Ice-retreat enables landscape transitions from proglacial towards a paraglacial environ-ment, allowing the formation of newly formed cryogenic deposits. Ice-surface changes in the Central Andes(33°S), including the high-mountain areas from Aconcagua, Mendoza and Maipo basins (Argentina and Chile),were studied using digitalized maps, aerial photographs, Landsat (1–8) and Sentinel-2A data for the periodbetween 1956 and 2015. Band ratio and Normalized Difference Snow Index (NDSI) methods were tested usingLandsat 8 and Sentinel-2A data for comparison. Geomorphological changes were assessed at Monos de Aguacatchment (2750–4000 m a.s.l.) in the Aconcagua basin (Chile) as a regionally representative landscape tran-sition case. Regional glacier shrinkage of 46 ± 5% between 1956 and 2016 was observed for the CentralAndean sub-basins in both Argentina and Chile at 33°S. Overall, 107.1 ± 5 km2of newly exposed surfaces aresubject to permafrost conditions. Such insights raise concern in terms of current and future environmental as-sessments for newly formed cryospheric elements in water scarce regions.1. IntroductionGlaciers around the world are losing mass at an unprecedented pacein the early 21st century (Zemp et al., 2015); South American Andes arenot exception (Davies and Glasser, 2012;Veettil et al., 2017a, 2017b).Andes Mountains in Chile and Argentina have more than 4000 km inlength from 17°30′Sto49oS, most of them are glacierized and the typeof glacier, climate, and topography vary latitudinally along the Andes(Lliboutry and Corte, 1998).Andean Glaciers can either belong to Dry Andes (17°30′Sto35oS) orWet Andes (35oSto49oS). Central Andes (between 31oS and 35oS),which is a part of the Dry Andes in Chile and Argentina, had a gla-cierized area of nearly 2200 km2(Lliboutry and Corte, 1998). Rock-glaciers, protalus and gelifluction lobes are predominant cryoformsbetween 31°S and 33°S and white glaciers are predominant featuresbetween 33°S and 49°S (García et al., 2017). The Andes MountainRange at 33°S has neoglacial and glacial limits oscillating between 3000and 3300 m a.s.l. for Chile and between and 3400–3650 m a.s.l. forArgentina, respectively (Espizua, 1993), despite the fact that thesemountain ranges belongs to similar climatic conditions.Photogrammetry and remote sensing have been a complementaryand sometimes alternative for traditional glaciological observations athigh altitudes (Paul et al., 2016; Veettil and de Souza, 2017). Recently,Veettil and Kamp (2017)discussed the suitability of various remotesensing data and methods for long-term monitoring of snow and ice inthe tropical Andes, mentioning the potential of high spatial resolutionsatellite data for delineating glacier boundaries. Medium resolutionLandsat series satellite data were mostly used since mid-1970s and thelatest of this series–Landsat 8 Operational Land Imager (OLI)–hasbetter geometric stability and radiometric performance (Kääb et al.,2016). Recently, images from the multispectral instrument (MSI) of theSentinel-2A satellite launched by the European Space Agency (ESA) areavailable at no cost from the United States Geological Survey (USGS).These data have been predicted to enhance worldwide glacier mon-itoring (Kääb et al., 2016) and have a spatial resolution of 10 m in fourand 20 m in six visible and infrared channels, instead of 15–30 m forLandsat 8. Further improvement is the higher temporal resolution (10days for Sentinel 2A instead of 16 days for Landsat 8 and better swathhttps://doi.org/10.1016/j.jsames.2019.102249Received 13 March 2019; Received in revised form 6 June 2019; Accepted 24 June 2019∗Corresponding author. Ton Duc Thang University, Ho Chi Minh City, Vietnam.E-mail address:bijeesh.veettil@tdtu.edu.vn(B.K. Veettil).Journal of South American Earth Sciences 94 (2019) 102249Available online 27 June 20190895-9811/ © 2019 Elsevier Ltd. All rights reserved.T | |
| Governing nature-based tourism mobility in National Park Torres del Paine, Chilean Southern Patagonia | Mobilities | Ruiz, J.; Lamers, M.; Bush, S.; Wells, G. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.1080/17450101.2019.1614335 | https://www.tandfonline.com/doi/full/10.1080/17450101.2019.1614335 | 745-761 | Vol: 14 Issue: 6 | 1745-0101, 1745-011X | Thomson Reuters ISI (SSCI) | All Open Access; Hybrid Gold Open Access | English | Nature-based tourism is a mobile activity shaped by the capacity of tourists for displacement and the socio-material infrastructure allowing flows. However, the literature has scarcely addressed aspects of mobility in governing nature-based tourism. Taking the case of the National Park Torres del Paine we explore three aspects of mobility in nature-based tourism using the concepts of routes, frictions, and rhythms. Our findings show that the movement of tourists challenges spatially bounded forms of governance. Instead, we argue, new mobility-sensitive forms of nature-based tourism governance are needed that can complement the use of fixed-boundary conservation enclosures. |
| Detecting Nothofagus pumilio Growth Reductions Induced by Past Spring Frosts at the Northern Patagonian Andes | Frontiers in Plant Science | Sangüesa-Barreda, G.; Villalba, R.; Rozas, V.; Christie, D.; Olano, J. | 2019 | Agua y Extremos | 10.3389/fpls.2019.01413 | https://www.frontiersin.org/article/10.3389/fpls.2019.01413/full | 1413 | Vol: 10 | 1664-462X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Extreme climatic events, such as late frosts in spring during leaf flush, have considerable impacts on the radial growth of temperate broadleaf trees. Albeit, all broadleaved species are potentially vulnerable, damage depends on the particularities of the local climate, the species, and its phenology. The impact of late spring frosts has been widely investigated in the Northern Hemisphere, but the potential incidence in Southern Hemisphere tree species is still poorly known. Here, we reconstruct spring frost occurrence at 30 stands of the deciduous tree Nothofagus pumilio in its northern range of distribution in the Patagonian Andes. We identified tree ring-width reductions at stand level not associated with regional or local drought events, matching unusual minimum spring temperatures during leaf unfolding. Several spring frosts were identified along the northern distribution of N. pumilio, being more frequent in the more continental Argentinean forests. Spring frost in 1980 had the largest spatial extent. The spring frosts in 1980 and 1992 also induced damages in regional orchards. Spring frost damage was associated with (i) a period of unusually warm temperatures at the beginning of leaf unfolding, followed by (ii) freezing temperatures. This study helps expand our understanding of the climatic constraints that could determine the future growth and dynamics of Andean deciduous forests and the potential use of tree-rings as archives of extreme events of spring frosts in northern Patagonia. |
| FROM THE PACIFIC TO THE TROPICAL FORESTS: NETWORKS OF SOCIAL INTERACTION IN THE ATACAMA DESERT, LATE IN THE PLEISTOCENE | Chungará (Arica) | Santoro, C.; Gayo, E.; Capriles, J.; Rivadeneira, M.; Herrera, K.; Mandakovic, V.; Rallo, M.; Rech, J.; Cases, B.; Briones, L.; Olguín, L.; Valenzuela, D.; Borrero, L.; Ugalde, P.; Rothhammer, F.; Latorre, C.; Szpak, P. | 2019 | Ciudades Resilientes | 10.4067/S0717-73562019005000602 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-73562019005000602&lng=en&nrm=iso&tlng=en | 5-25 | Vol: 51 Issue: 1 | 0717-7356 | Thomson Reuters ISI (SSCI) | All Open Access; Gold Open Access | English | The social groups that initially inhabited the hyper arid core of the Atacama Desert of northern Chile during the late Pleistocene integrated a wide range of local, regional and supra regional goods and ideas for their social reproduction as suggested by the archaeological evidence contained in several open camps in Pampa del Tamarugal (PdT). Local resources for maintaining their every-day life, included stone raw material, wood, plant and animal fibers, game, and fresh water acquired within a radius of -30 km (ca. 1-2 days journey). At a regional scale, some goods were introduced from the Pacific coast (60-80 km to the west, ca. 3-4 days journey), including elongated rounded cobbles used as hammer stones in lithic production, and shells, especially from non-edible species of mollusks. From the Andes (ranging 80-150 km to the east, ca. 5-8 days of journey), they obtained camelid fiber, obsidian and a high-quality chalcedony, in addition to sharing knowledge on projectile point designs (Patapatane and Tuina type forms). Pieces of wood of a tropical forest tree species (Ceiba spp.) from the east Andean lowlands (600 km away, ca. 30 days of journey) were also brought to the PdT. While local goods were procured by the circulation of people within the PdT, the small number of foreign items would have been acquired through some sort of exchange networks that integrated dispersed local communities throughout several ecosystems. These networks may have been a key factor behind the success exhibited by these early hunter-gatherers in the hyper arid ecosystems of the Atacama Desert at the end of the Pleistocene. Different lines of archaeological evidence including open camps, workshop-quarries, lithic artifacts, archaeofaunal remains, plant and animal fibers and textiles, archaeobotanical remains, and paleoecological data show that people of the PdT managed a wide range of cultural items from the Pacific coast, the Andean highland and the tropical forest, that were integrated with resources gathered locally within the socio-cultural systems established by the end of the Pleistocene. These results are interpreted as material expressions of multi-scalar networking for resource management and other social material and immaterial requirements, which in other words, means that these people were actively connected to regional (coastal and highland), and supra-regional (trans-Andean) exchange networks from and out of the PdT. |
| Perceptions of climate change on the Island of Chiloé: Challenges for local governance | Magallania | Sapiains A., R.; Ugarte C., A.; Hasbún M., J. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.4067/S0718-22442019000100083 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-22442019000100083&lng=en&nrm=iso&tlng=en | 83-103 | Vol: 47 Issue: 1 | 0718-2244 | Thomson Reuters ISI (SSCI) | All Open Access; Gold Open Access; Green Open Access | Spanish | Chiloé is an island in the south of Chile that presents multiple issues associated with the nonsustainable use of natural resources and high levels of poverty and inequality. Using qualitative methods, this article explores how keys stakeholders are perceiving and responding to climate change in such a complex social and environmental context. Results show this phenomenon is perceived as an emergent issue, whose social and environmental impacts are already happening. Generally individual responses are implemented, prevailing power asymmetries and competition over cooperation, coordination and exchange of experiences between stakeholders. A climate change governance system for the island should deal not only with institutional barriers but also promote social and cultural transformations. |
| Informe de Devolución Trabajando juntos por Placeres Alto: Prevención comunitaria de incendios forestales | Sapiains, R.; Aldunce, P.; Ugarte, A.; Marchant, G.; Inostroza, V.; Romero, J. | 2019 | https://www.cr2.cl/informe-valparaiso/ | 16 | Spanish | El incremento en la frecuencia e intensidad de los incendios es una de las consecuencias esperadas del cambio climático a nivel global. En Chile, se trata de una problemática que cada año cobra mayor importancia considerando sus múltiples impactos humanos, económicos y ambientales | |||||||
| Euro-Mediterranean climate variability in boreal winter: a potential role of the East Asian trough | Climate Dynamics | Sen, O.; Ezber, Y.; Bozkurt, D. | 2019 | Zonas Costeras | 10.1007/s00382-018-4573-9 | http://link.springer.com/10.1007/s00382-018-4573-9 | 7071-7084 | Vol: 52 Issue: 11 | 0930-7575 | Thomson Reuters ISI (SCIE) | English | Euro-Mediterranean climate variability has been associated mostly with the upstream atmospheric circulation and teleconnection patterns, the North Atlantic Oscillation and European blocking being the main ones. This study shows, for the first time, that the East Asian trough (EAT), a prominent circulation feature of the mid-troposphere in the downstream side, might exert a strong and significant role on the interannual variability of the Euro-Mediterranean climate during boreal winters. We performed empirical orthogonal function analysis on the regions of the EAT and Mediterranean trough (MedT), an important system modulating the climate of the region, to obtain the respective dominant modes of variability at 500-hPa geopotential heights. It appears that the leading modes, the intensity in the case of the EAT and the zonal displacement in the case of the MedT, are significantly correlated with each other (r = − 0.64, p < 0.001). Consequently, when the EAT is strong (weak), the MedT is observed in the west (east) of its climatological location resulting in a warmer (cooler) Middle East and northeastern Africa, a cooler (warmer) western Europe and northwestern Africa, and wetter (dryer) Italian, Balkan and Anatolian peninsulas. Given the fact that the EAT is also a key determinant of the East Asian winter climate, the identified mid-tropospheric link between East Asia and Mediterranean could help interpret some temperature and precipitation co-variability on the opposite sides of the Eurasian continent. We suggest that studies involving the Euro-Mediterranean climate should also consider the role of the EAT as it seems to be a potential driver of the year-to-year, perhaps longer-term, climate variability in the region. | |
| Monsoon Responses to Climate Changes—Connecting Past, Present and Future | Current Climate Change Reports | Seth, A.; Giannini, A.; Rojas, M.; Rauscher, S.; Bordoni, S.; Singh, D.; Camargo, S. | 2019 | Gobernanza e Interfaz Ciencia y Política | 10.1007/s40641-019-00125-y | http://link.springer.com/10.1007/s40641-019-00125-y | 63–79 | Vol: 5 | 2198-6061 | Thomson Reuters ISI (SCIE) | English | Purpose of Review: Knowledge of how monsoons will respond to external forcings through the twenty-first century has been confounded by incomplete theories of tropical climate and insufficient representation in climate models. This review highlights recent insights from past warm climates and historical trends that can inform our understanding of monsoon evolution in the context of an emerging energetic framework. Recent Findings: Projections consistent with paleoclimate evidence and theory indicate expanded/wetter monsoons in Africa and Asia, with continued uncertainty in the Americas. Twentieth century observations are not congruent with expectations of monsoon responses to radiative forcing from greenhouse gases, due to the confounding effect of aerosols. Lines of evidence from warm climate analogues indicate that while monsoons respond in globally coherent and predictable ways to orbital forcing and inter-hemispheric thermal gradients, there are differences in response to these forcings and also between land and ocean. Summary: Further understanding of monsoon responses to climate change will require refinement of the energetic framework to incorporate zonal asymmetries and the use of model hierarchies. © 2019, Springer Nature Switzerland AG. | |
| A perched, high-elevation wetland complex in the Atacama Desert (northern Chile) and its implications for past human settlement | Quaternary Research | Sitzia, L.; Gayo, E.; Sepulveda, M.; González, J.; Ibañez, L.; Queffelec, A.; De Pol-Holz, R. | 2019 | Ciudades Resilientes | 10.1017/qua.2018.144 | https://www.cambridge.org/core/product/identifier/S0033589418001448/type/journal_article | 33-52 | Vol: 92 Issue: 1 | 0033-5894 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | A previously undocumented type of wetland is described from the Atacama Desert in northern Chile (3000 m above sea level), sustained exclusively by direct precipitation and perched above the regional water table. Geomorphological mapping, pedostratigraphy, geochemistry, and analysis of contemporary vegetation is used to understand wetland formation and dynamics during historical and present time periods. The paleowetland deposits overlie a Miocene tuff that acts as an impermeable barrier to water transfer and creates conditions for local shallow ground water. These deposits include several paleosols that were formed during periods when precipitation increased regionally at 7755–7300, 1270, 545, and 400–300 cal yr BP. The similarity in timing with other palaeohydrological records for the Atacama implies that paleosols from this wetland are proxies for reconstructing past changes in local and regional hydrological cycle. Archaeological investigations have revealed the presence of two small farms from the Late Intermediate period, i.e., during the earliest wetter phase represented by the paleosols. Both farms are located near the paleowetland deposits, which suggests that local inhabitants exploited these water sources during late pre-Hispanic times. Results of this study improve knowledge of settlement patterns during this and earlier cultural periods. |
| Perception of thermal comfort in outdoor public spaces in the medium-sized city of Chillán, Chile, during a warm summer | Urban Climate | Smith, P.; Henríquez, C. | 2019 | Ciudades Resilientes | 10.1016/j.uclim.2019.100525 | https://linkinghub.elsevier.com/retrieve/pii/S2212095518301962 | 100525 | Vol: 30 | 2212-0955 | Thomson Reuters ISI (SCIE) | English | The study of thermal comfort in Latin American cities has been gaining great relevance for urban environmental planning. Some studies have evaluated the relationship between environmental and perceived comfort; however, the causes and social determinants of the different perceptions of the population have not been explored. The perception of thermal comfort in public spaces in the city of Chillán (Chile), which has an inland Mediterranean climate, is discussed in this context. First, we measured the environmental thermal comfort, adapting the Actual Sensation Vote index. A survey of 362 users of the five selected public spaces was carried out between 29 January and 01 February 2016 to obtain perceived comfort and relate it to the individual climatic history, use of public space and place of residence in the city. The results show that perceived thermal discomfort dominates over comfort on summer days; however, those users who visit public spaces for recreational purposes feel more comfortable, as well as those living in low socioeconomic status (SES) neighborhoods. On the other hand, users living in areas with higher socioeconomic status, have higher expectations regarding thermal environmental conditions. | |
| Public Spaces as Climate Justice Places? Climate Quality in the City of Chillán, Chile | Environmental Justice | Smith, P.; Henríquez, C. | 2019 | Ciudades Resilientes | 10.1089/env.2018.0041 | https://www.liebertpub.com/doi/10.1089/env.2018.0041 | 164-174 | Vol: 12 Issue: 4 | 1939-4071, 1937-5174 | Thomson Reuters ISI (ESCI) | English | The transformations brought about by climate change and the continued growth of cities are having an impact on urban climate. In urban spaces, especially in public spaces, environmental conditions are becoming more uncomfortable and this is affecting the health and quality of life of city dwellers. This study of climate quality in the city of Chillán revealed that there are insufficient public spaces to provide acceptable environmental quality for the entire population. It also showed that high-income areas, located in the peri-urban zones of the city, enjoy a better climate, environment, and air quality. This article analyzes urban climate injustice, as evidenced by the sharp socioeconomic differences in the quality of environment to which urban residents are exposed, and highlights the need for public spaces to improve the environmental quality for residents. © 2019, Mary Ann Liebert, Inc. | |
| Salmon farming vulnerability to climate change in southern Chile: understanding the biophysical, socioeconomic and governance links | Reviews in Aquaculture | Soto, D.; León‐Muñoz, J.; Dresdner, J.; Luengo, C.; Tapia, F.; Garreaud, R. | 2019 | Agua y Extremos | 10.1111/raq.12336 | https://onlinelibrary.wiley.com/doi/abs/10.1111/raq.12336 | 354-374 | Vol: 11 Issue: 2 | 1753-5123, 1753-5131 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | There has been a growing interest in studying the labile C pool in order to promote the sequestration and stabilization of soil organic carbon (SOC). Although labile SOC fractions have emerged as standardized indicators because of their potential to detect early SOC trends over time, the relationships between microbial attributes and labile SOC remains poorly understood. In this study, we explored the influence of labile SOC fractions on the topsoil bacteria-archaea community across 28 sites with different land use, climate aridity, and soil types across a wide range of SOC content (0.6–12%) in central Chile. We applied Illumina sequencing to the 16S rRNA to examine shifts in the diversity and composition of these soil microbial communities. Additionally, labile SOC fractions such as the permanganate oxidizable carbon (POXC) and light fraction organic matter (LFOM), along with the soil physicochemical properties were analyzed. The results demonstrated that among all of the environmental factors tested, the pH, POXC/SOC ratio and LFOM were key drivers of microbial community structure (β-diversity). The α-diversity metrics exhibited a decreasing trend when aridity increased, and community structure was found to vary, with high POXC/SOC in sites associated with drier conditions. In addition, POXC/SOC ratios and LFOM were clearly related to shifts in the relative abundances of specific taxonomic groups at genera level. When there was high POXC/SOC and low LFOM content, members of Bacteroidetes (Adhaeribacter, Flavisolibacter, and Niastella), Proteobacteria (Skermanella, Ramlibacter, and Sphingomonas), and Archaea (Thaumarchaeota) were found to be the most dominant groups; however, the microbial taxa responded differently to both labile C fraction types. These results have implications for understanding how labile C content can potentially be used to predict shifts in the microbial community, thus facilitating the development of predictive ecosystem models, as well as early warning indicators for soil degradation. |
| Assessment of soil physical properties' statuses under different land covers within a landscape dominated by exotic industrial tree plantations in south-central Chile | Journal of Soil and Water Conservation | Soto, L.; Galleguillos, M.; Seguel, O.; Sotomayor, B.; Lara, A. | 2019 | Cambio de Uso de Suelo | 10.2489/jswc.74.1.12 | http://www.jswconline.org/lookup/doi/10.2489/jswc.74.1.12 | 12-23 | Vol: 74 Issue: 1 | 0022-4561 | Thomson Reuters ISI (SCIE) | English | Land use and land cover changes (LULCC) within a highly anthropized Mediterranean landscape dominated by industrial tree plantation leads to degradation of soil physical properties. This process has been more intense in the coastal range of south-central%%%Chile due to its soils, which are highly susceptible to erosion, combined with a long history of intensive land use changes during the last century, transitioning from native forest (NF) to agriculture and the more recent establishment of Pinus radiata and Eucalyptus spp. exotic tree plantations. In this context, the aim of this study was to assess the statuses of soil physical properties over different land cover situations. Historical land cover maps were determined via supervised classifications using the maximum likelihood classifier applied to satellite imagery. Five land use and land cover categories (LULC) were defined according to main land cover transitions associated with active and abandoned forestry operations that have been reported in the region: NF, pine plantation (P), eucalyptus plantation (Eu), early successional (E-S), and secondary successional (S-S). Successional stages were generated using change detection statistics considering changes between 2001 and 2014 maps. Soil samples were collected at%%%three depths in 39 plots that describe the five LULC. High clay contents were found in all%%%the LULC except Eu and P. These sites have shown more signs of degradation, with lower%%%organic matter (SOM) and macropores and higher shear strength (ShS). Soil organic matter was consistent with litter contribution and quality, establishing lower bulk density (Db) for NF and S-S and higher values for Eu and E-S. ShS and dispersion rate (DR) exhibit a correlation with SOM with lower ShS and higher DR when SOM increased. Relevant differences were identified for structural stability index (SSI) between LULC depending on soil physical quality, besides a positive correlation with SOM. Those results show the need to generate appropriate conditions of vegetation cover in order to recover soils subjected to current forestry management of industrial plantations. | |
| Comité Científico COP25: Recursos hídricos en Chile: Impactos y adaptación al cambio climático. Informe de la mesa de Agua. | Stehr, A.; Álvarez, C.; Álvarez, P.; Arumí, J.; Baeza, C.; Barra, R.; Berroeta, C.; Castillo, Y.; Chiang, G.; Cotoras, D.; Crespo, S.; Delgado, V.; Donoso, G.; Dussaillant, A.; Ferrando, F.; Figueroa, R.; Frêne, C.; Fuster, R.; Godoy, A.; Gómez, T.; Holzapfel, E.; Huneeus, C.; Jara, M.; Little, C.; ... | 2019 | Agua y Extremos; Cambio de Uso de Suelo; Zonas Costeras | https://www.minciencia.gob.cl/comitecientifico/documentos/mesa-agua/19.Agua-Recursos-Hidricos-Stehr.pdf | La comparación entre el período 1985-2015 y el período 2030-2060 indica una disminución generalizada de las precipitaciones en comparación con la media histórica, pues se proyectan disminuciones promedio de entre 5% y 15% para la zona comprendida entre las cuencas de los ríos Elqui (región de Coquimbo) y el Baker (región de Aysén). Estas proyecciones se acentuarían hacia la zona sur del país, sobre todo entre la cuenca del río Biobío y el límite sur de la región de Los Lagos (Rojas, 2012). De acuerdo con trabajos como Boisier et al. (2016), se han detectado tendencias climáticas recientes en precipitación que siguen la misma dirección proyectada hacia el futuro y que han sido además atribuidas a una manifestación temprana del cambio climático | ||||||||
| A vertical forest within the forest: millenary trees from the Valdivian rainforest as biodiversity hubs | Ecology | Tejo, C.; Fontúrbel, F. | 2019 | Cambio de Uso de Suelo | 10.1002/ecy.2584 | http://doi.wiley.com/10.1002/ecy.2584 | e02584 | Vol: 100 Issue: 4 | 0012-9658 | Thomson Reuters ISI (SCIE) | English | Alerce (Fitzroya cupressoides (Molina) I.M. Johnst., Cupressaceae), known as Lahuan by the Mapuche people, is the most iconic endemic conifer of southern Chile and adjacent Argentina (Fig. 1). It can reach monumental dimensions (up to 5 m in diameter and over 50 m in height) and has remarkable longevity (Lara et al. 1999, Clement et al. 2001, Donoso‐Zeggers 2006, Urrutia‐Jalabert et al. 2015). The oldest alerce tree recorded is over 3,600 years old, making this species the second longest‐lived tree in the world after the North American Bristlecone pine (Pinus longaeva D. K. Bailey) (Lara and Villalba 1993). | |
| Analysis of exposure to fine particulate matter using passive data from public transport | Atmospheric Environment | Trewhela, B.; Huneeus, N.; Munizaga, M.; Mazzeo, A.; Menut, L.; Mailler, S.; Valari, M.; Ordoñez, C. | 2019 | Ciudades Resilientes | 10.1016/j.atmosenv.2019.116878 | https://linkinghub.elsevier.com/retrieve/pii/S1352231019305084 | 116878 | Vol: 215 | 1352-2310 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The city of Santiago experiences extreme pollution events during winter due to particulate matter and the associated health impact depends on the exposure to this pollutant, particularly to PM2.5. We present and apply a method that estimates the exposure of users of the public transport system of Santiago by combining smart card mobility data with measured surface concentrations from the monitoring network of Santiago and simulated concentrations by the CHIMERE model. The method was applied between July 20th and 24th of 2015 to 105,588 users corresponding to 12% of the frequent users of the public transport system and approximately 2% of the total population of Santiago. During those five days, estimated exposure based on measured concentrations varied between 44 and 75 μg/m3 while exposure based on simulated concentrations varied between 45 and 89 μg/m3. Furthermore, including socioeconomic conditions suggests an inverse relationship between exposure and income when measured concentrations are used, i.e. the lower the income the higher the exposure, whereas no such relationship is observed when using simulated concentrations. Although only exposure to PM2.5 was considered in this study, the method can also be applied to estimate exposure to other urban pollutant such as ozone. |
| Tras la huella del Cambio Climático | Troncoso, M.; Rudloff, V. | 2019 | Agua y Extremos; Cambio de Uso de Suelo | https://www.cr2.cl/wp-content/uploads/2019/10/Tras-la-Huella-del-Cambio-Clima%CC%81tico.pdf | 59 | Spanish | El cambio climático es una realidad y Chile no está exento de su amenaza. En la última década se ha observado un aumento generalizado de las temperaturas a nivel global, además de otros eventos y alteraciones climáticas en distintas latitudes del planeta, las que han repercutido desfavorablemente en la población. Esto, sumado a la acelerada extinción de especies en el último siglo, nos muestra lo vulnerable que es la vida frente al cambio climático. Nuestro país también se ha visto afectado con las recientes olas de calor y un prolongado défcit de precipitaciones en gran parte de su territorio, lo cual corresponde a la antesala de las proyecciones climáticas para este fn de siglo. Entonces, ¿cómo será la vida en el futuro cercano? El cambio climático que estamos presenciando ha sido producto de la actividad humana, y afecta tanto a las personas y todas sus actividades, como a los ecosistemas que habitan el planeta. Es entonces fundamental hacernos cargo de este problema como sociedad, y para ello debemos entenderlo, estudiarlo y analizarlo desde distintos ángulos, como es desde las ciencias sociales y ciencias naturales. La presente guía de apoyo educacional busca abordar el cambio climático desde este último punto: las ciencias naturales. Presentación; ¿Por qué hacer esta guía de actividades? La comunidad científca ha sido clave en evidenciar el cambio climático, mostrando los motivos y sus posibles consecuencias. Pero esto no basta, ya que toda la sociedad debe ser partícipe a la hora de actuar en su contra. Luego, las personas deben entender la ciencia en torno al cambio climático, y esto comienza desde lo básico: el método científco. Esta guía es, pues, un viaje hacia la indagación científca dentro del marco del medio ambiente, y es importante que profesores y estudiantes trabajen juntos en este nuevo camino. ¿Por qué Chile es vulnerable al cambio climático? ¿Qué estamos haciendo y qué haremos en el futuro? Son preguntas que se están haciendo cada vez más frecuentes tanto en jóvenes como adultos. Es por tanto ahora el momento de que el aula de clases se vuelva un espacio de conversación sobre el cambio climático, y no solo como un tema de carácter global, sino también dentro la experiencia del entorno próximo. Solo mediante la observación de nuestro contexto, el medio ambiente y nuestra historia, es que como sociedad podremos hacer frente al cambio climático. | ||||||
| In-stream wetland deposits, megadroughts, and cultural change in the northern Atacama Desert, Chile | Quaternary Research | Tully, C.; Rech, J.; Workman, T.; Santoro, C.; Capriles, J.; Gayo, E.; Latorre, C. | 2019 | Ciudades Resilientes | 10.1017/qua.2018.122 | https://www.cambridge.org/core/product/identifier/S0033589418001229/type/journal_article | 63-80 | Vol: 91 Issue: 1 | 0033-5894 | Thomson Reuters ISI (SCIE) | English | A key concern regarding current and future climate change is the possibility of sustained droughts that can have profound impacts on societies. As such, multiple paleoclimatic proxies are needed to identify megadroughts, the synoptic climatology responsible for these droughts, and their impacts on past and future societies. In the hyperarid Atacama Desert of northern Chile, many streams are characterized by perennial flow and support dense in-stream wetlands. These streams possess sequences of wetland deposits as fluvial terraces that record past changes in the water table. We mapped and radiocarbon dated a well-preserved sequence of in-stream wetland deposits along a 4.3-km reach of the Río San Salvador in the Calama basin to determine the relationship between regional climate change and the incision of in-stream wetlands. The Río San Salvador supported dense wetlands from 11.1 to 9.8, 6.4 to 3.5, 2.8 to 1.3, and 1.0 to 0.5 ka and incised at the end of each of these intervals. Comparison with other in-stream wetland sequences in the Atacama Desert, and with regional paleoclimatic archives, indicates that in-stream wetlands responded similarly to climatic changes by incising during periods of extended drought at ~9.8, 3.5, 1.3, and 0.5 ka. | |
| The influence of temperature and pH on bacterial community composition of microbial mats in hot springs from Costa Rica | MicrobiologyOpen | Uribe‐Lorío, L.; Brenes-Guillén, L.; Hernández‐Ascencio, W.; Mora‐Amador, R.; González, G.; Ramírez‐Umaña, C.; Díez, B.; Pedrós‐Alió, C. | 2019 | Zonas Costeras | 10.1002/mbo3.893 | https://onlinelibrary.wiley.com/doi/10.1002/mbo3.893 | art: e893 | Vol: 8 Issue: 10 | 2045-8827, 2045-8827 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | We used the 16S rRNA gene pyrosequencing approach to investigate the microbial diversity and community composition in several Costa Rican hot springs alongside the latitudinal axis of the country, with a range of temperatures (37–63°C), pH (6–7.5) and other geochemical conditions. A principal component analyses of the physicochemical parameters showed the samples were separated into three geochemically distinct habitats associated with the location (North, Central, and South). Cyanobacteria and Chloroflexi comprised 93% of the classified community, the former being the most abundant phylum in all samples except for Rocas Calientes 1, (63°C, pH 6), where Chloroflexi and Deinococcus-Thermus represented 84% of the OTUs. Chloroflexi were more abundant as temperature increased. Proteobacteria, Bacteriodetes and Deinococcus-Thermus comprised 5% of the OTUs represented. Other Phyla were present in very small percentages (<1%). A LINKTREE analysis showed that the community structure of the mats was shaped primarily by pH, separating samples with pH > 6.6 from samples with pH < 6.4. Thus, both pH and temperature were relevant for community composition even within the moderate ranges of variables studied. These results provide a basis for an understanding of the physicochemical influences in moderately thermophilic microbial mats. |
| Quality as a hidden dimension of energy poverty in middle-development countries. Literature review and case study from Chile | Energy and Buildings | Urquiza, A.; Amigo, C.; Billi, M.; Calvo, R.; Labraña, J.; Oyarzún, T.; Valencia, F. | 2019 | Ciudades Resilientes | 10.1016/j.enbuild.2019.109463 | https://linkinghub.elsevier.com/retrieve/pii/S0378778818319790 | 109463 | Vol: 204 | 0378-7788 | Thomson Reuters ISI (SCIE) | English | The paper proposes a literature review and meta-analysis on different dimensions and approaches with respect to energy poverty and examines Chile as a case study for its manifestations in middle development countries. This phenomenon has acquired greater relevance, with a variety of definitions, indicators and methodologies being used to measure it. However, most of them are focused on either quantifying the lack of access to modern energy services in poor countries or assessing the inequality produced by the costs of accessing such services in developed countries. This results in the lack of a proper toolbox to tackle middle development countries, such as Chile: where access-based measures assign thresholds that are too low, so that almost nobody is energy poor; conversely, equality-based measures deploy excessively high ones, so that a very large proportion of the population is energy poor. The paper argues that this deficit is caused by the understanding of quality in terms of “standards” in access- and equality-based measures, which restricts its potential in economically, culturally, and geographically diverse territories. A context-sensitive three-dimensional framework to assess energy poverty is then proposed, and its policy implications are briefly discussed. | |
| Gobernanza policéntrica y problemas ambientales en el siglo XXI: desafíos de coordinación social para la distribución de recursos hídricos en Chile | Persona y Sociedad | Urquiza, A.; Amigo, C.; Billi, M.; Cortés, J.; Labraña, J. | 2019 | Ciudades Resilientes | https://personaysociedad.uahurtado.cl/index.php/ps/article/view/258 | 133-160 | Vol: 33 | 0719-0883 | Latindex | Spanish | La sociedad contemporánea debe lidiar con importantes transformaciones en su entorno biofísico, impulsando una reflexión en las ciencias sociales y ecológicas sobre las características que deben tener los procesos de gobernanza ambiental, especialmente frente a aquellos bienes que adolecen de límites de propiedad y dominio haciendo surgir problemas de coordinación (por ejemplo la ‘tragedia de los comunes’). La literatura al respecto destaca la existencia de distintos niveles organizacionales y escalas territoriales que deberían ser articulados (coordinación vertical). Si bien este tipo de gobernanza, denominada policéntrica, ha tenido un creciente impacto en la discusión científica, en este artículo se argumenta que los análisis omiten un atributo central de la sociedad moderna –las racionalidades comunicativas autónomas (coordinación horizontal)– cuya consideración es necesaria para diseñar formas efectivas de gobernanza ambiental. Para sostener esta tesis, se analiza la institucionalidad relacionada con la gobernanza hídrica en Chile, discutiendo la clásica polarización entre Estado y mercado, e identificando esfuerzos policéntricos. Paralelamente se analizan los principios teóricos que establecen la necesidad de considerar distintas racionalidades comunicativas al momento de diseñar políticas enfocadas en el tratamiento de problemas ambientales. Finalmente, se identifican inciativas ya existentes en esta línea y desafíos relacionados con su aplicación a la gobernanza hídrica. | ||
| Andean caravan ceremonialism in the lowlands of the Atacama Desert: The Cruces de Molinos archaeological site, northern Chile | Quaternary International | Valenzuela, D.; Cartajena, I.; Santoro, C.; Castro, V.; Gayo, E. | 2019 | Ciudades Resilientes | 10.1016/j.quaint.2018.09.016 | https://linkinghub.elsevier.com/retrieve/pii/S1040618218301101 | 37-47 | Vol: 533 | 10406182 | Thomson Reuters ISI (SCIE) | English | Camelid caravans have played a key role in the complex systems of interregional social interaction that characterizes Andean history. In the northernmost region of Chile, the most frequent archaeological indicators of these caravan systems are trails and rock art images. Cruces de Molinos (LL-43), a rock art site in the Lluta valley, 1100 masl, 40 km from the Pacific littoral, expands the ceremonial role of rock art sites, materialized, not only as regards the iconography portrayed and alluding to these practices, but also in terms of articulated carcass remains and detached anatomical units of camelids, intentionally deposited in a cache beneath one of the engraved blocks. This paper analyzes the site considering the visual imagery, spatial location, archaeological deposits and features associated with rock art. Based on the predominance of camelid and caravan motifs in rock art images, the extraordinary setting and location of the site on the valley's upper slopes, which is far removed from local settlements, but closely connected with a llama caravan trade network linking the chaupiyunga ecozone with the highlands (sierra and Altiplano ecozones), we suggest that Cruces de Molinos was not a rest stop for caravanners, but a ceremonial place, and not for local farmers, but for highland herders. According to seven accelerator mass spectrometry (AMS) dates that place the occupation between cal. 1060–1190 CE in the Late Intermediate period. |
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| Extreme Daily Rainfall in Central-Southern Chile and Its Relationship with Low-Level Horizontal Water Vapor Fluxes | Journal of Hydrometeorology | Valenzuela, R.; Garreaud, R. | 2019 | Agua y Extremos | 10.1175/JHM-D-19-0036.1 | http://journals.ametsoc.org/doi/10.1175/JHM-D-19-0036.1 | 1829-1850 | Vol: 20 Issue: 9 | 1525-755X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Extreme rainfall events are thought to be one of the major threats of climate change given an increase of water vapor available in the atmosphere. However, before projecting future changes in extreme rainfall events, it is mandatory to know current patterns. In this study we explore extreme daily rainfall events along central-southern Chile with emphasis in their spatial distribution and concurrent synoptic-scale circulation. Surface rain gauges and reanalysis products from the Climate Forecast System Reanalysis are employed to unravel the dependency between extreme rainfall and horizontal water vapor fluxes. Results indicate that extreme rainfall events can occur everywhere, from the subtropical to extratropical latitudes, but their frequency increases where terrain has higher altitude, especially over the Andes Mountains. The majority of these events concentrate in austral winter, last a single day, and encompass a north–south band of about 200 km in length. Composited synoptic analyses identified extreme rainfall cases dominated by northwesterly (NW) and westerly (W) moisture fluxes. Some features of the NW group include a 300-hPa trough projecting from the extratropics to subtropics, a surface-level depression, and cyclonic winds at 850 hPa along the coast associated with integrated water vapor (IWV) > 30 mm. Conversely, features in the W group include both a very weak 300-hPa trough and surface depression, as well as coastal westerly winds associated with IWV > 30 mm. About half of extreme daily rainfall is associated with an atmospheric river. Extreme rainfall observed in W (NW) cases has a strong orographic (synoptic) forcing. In addition, W cases are, on average, warmer than NW cases, leading to an amplified hydrological response. |
| Comité Científico COP25: Lineamientos para el desarrollo de planes de adaptación: Aplicación de recursos hídricos. Informe de las mesas Adaptación y Agua | Vicuña, S.; Aldunce, P.; Stehr, A.; Cid, F.; Rivera, A.; Alencar, K.; Álvarez, C.; Barton, J.; Berroeta, C.; Boisier, J.; Bustos, E.; Bustos, S.; Correa, T.; Cortés, S.; Cubillos, L.; De la Barrera, F.; Donoso, F.; Farías, L.; Farías, D.; Fuster, R.; Gese, P.; Godoy, A.; Guerra, L.; Guida, C.; Ibarr... | 2019 | Agua y Extremos; Zonas Costeras | https://cdn.digital.gob.cl/filer_public/f3/56/f3566a93-a46c-49cf-a73d-86d4a807a5b5/2adaptacion-lineamientosrrhh-vicuna.pdf | La planificación y sus instrumentos de aplicación, como los planes de adaptación, son herramientas fundamentales para abordar los desafíos de la adaptación a distintas escalas espaciales y sectoriales. El uso real de estas herramientas aún es limitado. Su aplicación es dispar, especialmente en el contexto de la región de América Latina. Pocos países han iniciado sus procesos de desarrollo de este tipo de herramientas, y donde se ha hecho, como en Chile, existen vacíos y brechas importantes para desarrollar su potencial. A través de un proceso participativo a lo largo del año basado en talleres con la comunidad científica, se generó una propuesta de lineamientos para el diseño, implementación y seguimiento de planes de adaptación, la que además fue implementada de manera práctica en un ejercicio hipotético de desarrollo de un Plan de Adaptación al Cambio Climático (PACC) para los Recursos Hídricos. Un lineamiento relevante tiene relación con los antecedentes y el proceso de diseño del plan. El explicitar el proceso de diseño utilizado es fundamental para otorgar transparencia y, por lo tanto, validez al plan. En el trabajo de diseño resulta crítico contar con procesos participativos que permitan identificar las principales vulnerabilidades, desafíos y objetivos hacia el futuro. En el contexto de los recursos hídricos esta necesidad es más patente, por lo que se requiere un proceso de participación lo más amplio posible, pero teniendo en cuenta que no es factible —ni deseable— que se incluyan en el desarrollo del plan medidas de adaptación muy específicas en virtud de las necesidades en cada territorio. Estas medidas se deben desarrollar, por ejemplo, en el contexto de planes de acción a una escala regional. Se propone que este proceso se desarrolle al alero de las discusiones que se van a generar respecto de los lineamientos generales de la gestión de recursos hídricos en el país, y en paralelo de las gestiones que actualmente se tienen que desarrollar para resolver los desafíos de la actual megasequía | ||||||||
| The last glacial termination in the Coyhaique sector of central Patagonia | Quaternary Science Reviews | Vilanova, I.; Moreno, P.; Miranda, C.; Villa-Martínez, R. | 2019 | Agua y Extremos | 10.1016/j.quascirev.2019.105976 | https://linkinghub.elsevier.com/retrieve/pii/S0277379119306572 | 105976 | Vol: 224 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | Southern South America is the only continental landmass that intersects the core of the Southern Westerly Winds (SWW), and thus is important for studying their role as a driver/conduit for the initiation/propagation of climate signals since the last glaciation. Their interaction with the Southern Ocean (SO) affects global climate through its influence on high-latitude upwelling and biological productivity, deep-water convection sites and, consequently, ventilation of CO2 from the deep ocean. Variations in the SWW-SO coupled system have been postulated as fundamental drivers of climate change during glacial terminations and the current interglacial. Hence, deciphering the evolution of the SWW from sensitive locations in the southern middle latitudes is essential for understanding important climatic transitions during and since the Last Glacial Termination (T1). Terrestrial records from the central Patagonian Andes (CPA) (44°-49°S), however, show heterogeneities in the timing, rates, and direction of climate change during T1, impeding detailed assessment of its drivers at regional, hemispheric, and global scales. Here we present new data on glacier, vegetation, and fire-regime changes in the Coyhaique sector (45°34′S) of CPA to improve our understanding on the timing and structure of the T1, including the behavior of the SWW. Our results indicate glacial recession from the youngest Last Glacial Maximum moraines just before ∼17.9 ka and development of an ice-dammed proglacial lake during the early stages of T1. Drainage of the ice-dammed lake, triggered by renewed glacial recession, was near-synchronous with the onset of a gradual multi-millennial trend toward arboreal dominance that started at ∼16 ka east and west of the Andes at that latitude. We detect increased influence of the SWW at ∼45°S starting at ∼16.6 ka, relative to the first millennium of T1, that led to positive anomalies in precipitation between ∼16–14.4 and ∼12.8–11.5 ka, followed by negative anomalies between ∼11.5–9 ka. The synchronous spread of arboreal vegetation east and west of the CPA divide during T1, despite the trans-Andean precipitation contrasts, suggests an upward shift in the temperature-controlled Andean tree line, underscoring the role of deglacial warming as the critical driver for afforestation at regional scale. | |
| First evidence for cold-adapted anaerobic oxidation of methane in deep sediments of thermokarst lakes | Environmental Research Communications | Winkel, M.; Sepulveda-Jauregui, A.; Martinez-Cruz, K.; Heslop, J.; Rijkers, R.; Horn, F.; Liebner, S.; Walter Anthony, K. | 2019 | Cambio de Uso de Suelo | 10.1088/2515-7620/ab1042 | http://stacks.iop.org/2515-7620/1/i=2/a=021002?key=crossref.5751fe233c14408fa25c87ac82e90cf1 | 021002 | Vol: 1 Issue: 2 | 2515-7620 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Microbial decomposition of thawed permafrost carbon in thermokarst lakes leads to the release of ancient carbon as the greenhouse gas methane (CH4), yet potential mitigating processes are not understood. Here, we report δ 13C–CH4 signatures in the pore water of a thermokarst lake sediment core that points towards in situ occurrence of anaerobic oxidation of methane (AOM). Analysis of the microbial communities showed a natural enrichment in CH4-oxidizing archaeal communities that occur in sediment horizons at temperatures near 0 °C. These archaea also showed high rates of AOM in laboratory incubations. Calculation of the stable isotopes suggests that 41 to 83% of in situ dissolved CH4 is consumed anaerobically. Quantification of functional genes (mcrA) for anaerobic methanotrophic communities revealed up to 6.7 ± 0.7 × 105 copy numbers g−1 wet weight and showed similar abundances to bacterial 16S rRNA gene sequences in the sediment layers with the highest AOM rates. We conclude that these AOM communities are fueled by CH4 produced from permafrost organic matter degradation in the underlying sediments that represent the radially expanding permafrost thaw front beneath the lake. If these communities are widespread in thermokarst environments, they could have a major mitigating effect on the global CH4 emissions. |
| Estimation of atmospheric total organic carbon (TOC) – paving the path towards carbon budget closure | Atmospheric Chemistry and Physics | Yang, M.; Fleming, Z. | 2019 | Ciudades Resilientes | 10.5194/acp-19-459-2019 | https://www.atmos-chem-phys.net/19/459/2019/ | 459-471 | Vol: 19 Issue: 1 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | The atmosphere contains a rich variety of reactive organic compounds, including gaseous volatile organic carbon (VOCs), carbonaceous aerosols, and other organic compounds at varying volatility. Here we present a novel and simple approach to measure atmospheric non-methane total organic carbon (TOC) based on catalytic oxidation of organics in bulk air to carbon dioxide. This method shows little sensitivity towards humidity and near 100% oxidation efficiencies for all VOCs tested. We estimate a best-case hourly precision of 8 ppbC during times of low ambient variability in carbon dioxide, methane, and carbon monoxide (CO). As proof of concept of this approach, we show measurements of TOCCCO during August–September 2016 from a coastal city in the southwest United Kingdom. TOCCCO was substantially elevated during the day on weekdays (occasionally over 2 ppm C) as a result of local anthropogenic activity. On weekends and holidays, with a mean (standard error) of 102 (8) ppb C, TOCCCO was lower and showed much less diurnal variability. TOCCCO was significantly lower when winds were coming off the Atlantic Ocean than when winds were coming off land if we exclude the weekday daytime. By subtracting the estimated CO from TOCCCO, we constrain the mean (uncertainty) TOC in Atlantic-dominated air masses to be around 23 ( 8) ppbC during this period. A proton-transfer-reaction mass spectrometer (PTR-MS) was deployed at the same time, detecting a large range of organic compounds (oxygenated VOCs, biogenic VOCs, aromatics, dimethyl sulfide). The total speciated VOCs from the PTRMS, denoted here as Sum(VOC), amounted to a mean (uncertainty) of 12 ( 3) ppbC in marine air. Possible contributions from a number of known organic compounds present in marine air that were not detected by the PTR-MS are assessed within the context of the TOC budget. Finally, we note that the use of a short, heated sample tube can improve the transmission of organics to the analyzer, while operating our system alternately with and without a particle filter should enable a better separation of semi-volatile and particulate organics from the VOCs within the TOC budget. Future concurrent measurements of TOC, CO, and a more comprehensive range of speciated VOCs would enable a better characterization and understanding of the atmospheric organic carbon budget. |
| Greenhouse gases, nutrients and the carbonate system in the Reloncaví Fjord (Northern Chilean Patagonia): Implications on aquaculture of the mussel, Mytilus chilensis, during an episodic volcanic eruption | Science of The Total Environment | Yevenes, M.; Lagos, N.; Farías, L.; Vargas, C. | 2019 | Zonas Costeras | 10.1016/j.scitotenv.2019.03.037 | https://linkinghub.elsevier.com/retrieve/pii/S0048969719310150 | 49-61 | Vol: 669 | 0048-9697 | Thomson Reuters ISI (SCIE) | English | This study investigates the immediate and mid-term effects of the biogeochemical variables input into the Reloncaví fjord (41°40′S; 72°23′O) as a result of the eruption of Calbuco volcano. Reloncaví is an estuarine system supporting one of the largest mussels farming production within Northern Chilean-Patagonia. Field-surveys were conducted immediately after the volcanic eruption (23–30 April 2015), one month (May 2015), and five months posterior to the event (September 2015). Water samples were collected from three stations along the fjord to determine greenhouse gases [GHG: methane (CH 4 ), nitrous oxide (N 2 O)], nutrients [NO 3 − , NO 2 − , PO 4 3− , Si(OH) 4 , sulphate (SO 4 2− )], and carbonate systems parameters [total pH (pHT), temperature, salinity, dissolved oxygen (O 2 ), and total alkalinity (AT)]. Additionally, the impact of physicochemical changes in the water column on juveniles of the produced Chilean blue mussel, Mytilus chilensis, was also studied. Following the eruption, a large phytoplankton bloom led to an increase in pH T , due to the uptake of dissolved-inorganic carbon in photic waters, potentially associated with the runoff of continental soil covered in volcanic ash. Indeed, high surface SO 4 2− and GHG were observed to be associated with river discharges. No direct evidence of the eruption was observed within the carbonate system. Notwithstanding, a vertical pattern was observed, with an undersaturation of aragonite (Ω Ar < 1) both in brackish surface (<3 m) and deep waters (>10 m), and saturated values in subsurface waters (3 to 7 m). Simultaneously, juvenile mussel shells showed maximized length and weight at 4 m depth. Results suggest a localized impact of the volcanic eruption on surface GHG, nutrients and short-term effects on the carbonate system. Optimal conditions for mussel calcification were identified within a subsurface refuge in the fjord. These specific attributes can be integrated into adaptation strategies by the mussel aquaculture industry to confront ocean acidification and changing runoff conditions. © 2019 Elsevier B.V. | |
| Insight into anthropogenic forcing on coastal upwelling off south-central Chile | Elem Sci Anth | Aguirre, C.; García-Loyola, S.; Testa, G.; Silva, D.; Farías, L. | 2018 | Zonas Costeras | 10.1525/elementa.314 | https://www.elementascience.org/article/10.1525/elementa.314/ | 59 | Vol: 6 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Coastal upwelling systems off the coasts of Peru and Chile are among the most productive marine ecosystems in the world, sustaining a significant percentage of global primary production and fishery yields. Seasonal and interannual variability in these systems has been relatively well documented; however, an understanding of recent trends and the influence of climate change on marine processes such as surface cooling and primary productivity is limited. This study presents evidence that winds favorable to upwelling have increased within the southern boundary of the Humboldt Current System (35°–42°S) in recent decades. This trend is consistent with a poleward movement of the influence of the Southeast Pacific Anticyclone and resembles the spatial pattern projected by Global Circulation Models for warming scenarios. Chlorophyll a levels (from 2002 to present) determined by satellite and field-based time-series observations show a positive trend, mainly in austral spring–summer (December–January–February), potentially explained by observed increments in nutrient flux towards surface waters and photosynthetically active radiation. Both parameters appear to respond to alongshore wind stress and cloud cover in the latitudinal range of 35°S to 42°S. In addition, net annual deepening of the mixed layer depth is estimated using density and temperature profiles. Changes in this depth are associated with increasing winds and may explain cooler, more saline, and more productive surface waters, with the latter potentially causing fluctuations in dissolved oxygen and other gases, such as nitrous oxide, sensitive to changes in oxygenation. We argue that these recent changes represent, at least in part, a regional manifestation of the Anthropocene along the Chilean coast. |
| Microbial activity during a coastal phytoplankton bloom on the Western Antarctic Peninsula in late summer | FEMS Microbiology Letters | Alcamán-Arias, M.; Farías, L.; Verdugo, J.; Alarcón-Schumacher, T.; Díez, B. | 2018 | Zonas Costeras | 10.1093/femsle/fny090 | https://academic.oup.com/femsle/article/doi/10.1093/femsle/fny090/4961137 | art: fny090 | Vol: 365 Issue: 10 | 1574-6968 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Phytoplankton biomass during the austral summer is influenced by freezing and melting cycles as well as oceanographic processes that enable nutrient redistribution in the West Antarctic Peninsula (WAP). Microbial functional capabilities, metagenomic and metatranscriptomic activities as well as inorganic 13C- and 15N-assimilation rates were studied in the surface waters of Chile Bay during two contrasting summer periods in 2014. Concentrations of Chlorophyll a (Chla) varied from 0.3 mg m−3 in February to a maximum of 2.5 mg m−3 in March, together with a decrease in nutrients; however, nutrients were never depleted. The microbial community composition remained similar throughout both sampling periods; however, microbial abundance and activity changed with Chla levels. An increased biomass of Bacillariophyta, Haptophyceae and Cryptophyceae was observed along with night-grazing activity of Dinophyceae and ciliates (Alveolates). During high Chla conditions, HCO3− uptake rates during daytime incubations increased 5-fold (>2516 nmol C L−1 d−1), and increased photosynthetic transcript numbers that were mainly associated with cryptophytes; meanwhile night time NO3− (>706 nmol N L−1 d−1) and NH4+ (41.7 nmol N L−1 d−1) uptake rates were 2- and 3-fold higher, respectively, due to activity from Alpha-/Gammaproteobacteria and Bacteroidetes (Flavobacteriia). Due to a projected acceleration in climate change in the WAP, this information is valuable for predicting the composition and functional changes in Antarctic microbial communities. |
| Diurnal Changes in Active Carbon and Nitrogen Pathways Along the Temperature Gradient in Porcelana Hot Spring Microbial Mat | Frontiers in Microbiology | Alcamán-Arias, M.; Pedrós-Alió, C.; Tamames, J.; Fernández, C.; Pérez-Pantoja, D.; Vásquez, M.; Díez, B. | 2018 | Zonas Costeras | 10.3389/fmicb.2018.02353 | https://www.frontiersin.org/article/10.3389/fmicb.2018.02353/full | art: 2353 | Vol: 9 | 1664-302X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Composition, carbon and nitrogen uptake, and gene transcription of microbial mat communities in Porcelana neutral hot spring (Northern Chilean Patagonia) were analyzed using metagenomics, metatranscriptomics and isotopically labeled carbon ((HCO3)-C-13) and nitrogen ((NH4Cl)-N-15 and (KNO3)-N-15) assimilation rates. The microbial mat community included 31 phyla, of which only Cyanobacteria and Chloroflexi were dominant. At 58 degrees C both phyla co-occurred, with similar contributions in relative abundances in metagenomes and total transcriptional activity. At 66 degrees C, filamentous anoxygenic phototrophic Chloroflexi were >90% responsible for the total transcriptional activity recovered, while Cyanobacteria contributed most metagenomics and metatranscriptomics reads at 48 degrees C. According to such reads, phototrophy was carried out both through oxygenic photosynthesis by Cyanobacteria (mostly Mastigocladus) and anoxygenic phototrophy due mainly to Chloroflexi. Inorganic carbon assimilation through the Calvin-Benson cycle was almost exclusively due to Mastigocladus, which was the main primary producer at lower temperatures. Two other CO2 fixation pathways were active at certain times and temperatures as indicated by transcripts: 3-hydroxypropionate (3-HP) bi-cycle due to Chloroflexi and 3-hydroxypropionate-4-hydroxybutyrate (HH) cycle carried out by Thaumarchaeota. The active transcription of the genes involved in these C-fixation pathways correlated with high in situ determined carbon fixation rates. In situ measurements of ammonia assimilation and nitrogen fixation (exclusively attributed to Cyanobacteria and mostly to Mastigocladus sp.) showed these were the most important nitrogen acquisition pathways at 58 and 48 degrees C. At 66 degrees C ammonia oxidation genes were actively transcribed (mostly due to Thaumarchaeota). Reads indicated that denitrification was present as a nitrogen sink at all temperatures and that dissimilatory nitrate reduction to ammonia (DNRA) contributed very little. The combination of metagenomic and metatranscriptomic analysis with in situ assimilation rates, allowed the reconstruction of day and night carbon and nitrogen assimilation pathways together with the contribution of keystone microorganisms in this natural hot spring microbial mat. |
| Temperature modulates Fischerella thermalis ecotypes in Porcelana Hot Spring | Systematic and Applied Microbiology | Alcorta, J.; Espinoza, S.; Viver, T.; Alcamán-Arias, M.; Trefault, N.; Rosselló-Móra, R.; Díez, B. | 2018 | Zonas Costeras | 10.1016/j.syapm.2018.05.006 | https://linkinghub.elsevier.com/retrieve/pii/S0723202018302297 | 531-543 | Vol: 41 Issue: 6 | 0723-2020 | Thomson Reuters ISI (SCIE) | English | In the Porcelana Hot Spring (Northern Patagonia), true-branching cyanobacteria are the dominant primary producers in microbial mats, and they are mainly responsible for carbon and nitrogen fixation. However, little is known about their metabolic and genomic adaptations at high temperatures. Therefore, in this study, a total of 81 Fischerella thermalis strains (also known as Mastigocladus laminosus) were isolated from mat samples in a thermal gradient between 61–46 °C. The complementary use of proteomic comparisons from these strains, and comparative genomics of F. thermalis pangenomes, suggested that at least two different ecotypes were present within these populations. MALDI-TOF MS analysis separated the strains into three clusters; two with strains obtained from mats within the upper temperature range (61 and 54 °C), and a third obtained from mats within the lower temperature range (51 and 46 °C). Both groups possessed different but synonymous nifH alleles. The main proteomic differences were associated with the abundance of photosynthesis-related proteins. Three F. thermalis metagenome assembled genomes (MAGs) were described from 66, 58 and 48 °C metagenomes. These pangenomes indicated a divergence of orthologous genes and a high abundance of exclusive genes at 66 °C. These results improved the current understanding of thermal adaptation of F. thermalis and the evolution of these thermophilic cyanobacterial species. | |
| The CAMELS-CL dataset - links to files. PANGAEA, https://doi.pangaea.de/10.1594/PANGAEA.894885 | PANGAEA - Data Publisher for Earth & Environmental Science | Alvarez, C.; Mendoza, P.; Boisier, J.; Addor, N.; Galleguillos, M.; Zambrano-Bigiarini, M.; Lara, A.; Puelma, C.; Cortes, G.; Garreaud, R.; McPhee, J.; Ayala, A. | 2018 | Agua y Extremos; Cambio de Uso de Suelo | 10.1594/PANGAEA.894885 | https://doi.org/10.1594/PANGAEA.894885 | |||||||
| The CAMELS-CL dataset: catchment attributes and meteorology for large sample studies – Chile dataset | Hydrology and Earth System Sciences | Alvarez-Garreton, C.; Mendoza, P.; Boisier, J.; Addor, N.; Galleguillos, M.; Zambrano-Bigiarini, M.; Lara, A.; Puelma, C.; Cortes, G.; Garreaud, R.; McPhee, J.; Ayala, A. | 2018 | Agua y Extremos; Cambio de Uso de Suelo | 10.5194/hess-22-5817-2018 | https://www.hydrol-earth-syst-sci.net/22/5817/2018/ | 5817-5846 | Vol: 22 Issue: 11 | 1607-7938 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | We introduce the first catchment dataset for large sample studies in Chile. This dataset includes 516 catchments; it covers particularly wide latitude (17.8 to 55.0°S) and elevation (0 to 6993ma.s.l.) ranges, and it relies on multiple data sources (including ground data, remote-sensed products and reanalyses) to characterise the hydroclimatic conditions and landscape of a region where in situ measurements are scarce. For each catchment, the dataset provides boundaries, daily streamflow records and basin-averaged daily time series of precipitation (from one national and three global datasets), maximum, minimum and mean temperatures, potential evapotranspiration (PET; from two datasets), and snow water equivalent. We calculated hydro-climatological indices using these time series, and leveraged diverse data sources to extract topographic, geological and land cover features. Relying on publicly available reservoirs and water rights data for the country, we estimated the degree of anthropic intervention within the catchments. To facilitate the use of this dataset and promote common standards in large sample studies, we computed most catchment attributes introduced by Addor et al. (2017) in their Catchment Attributes and MEteorology for Large-sample Studies (CAMELS) dataset, and added several others. We used the dataset presented here (named CAMELS-CL) to characterise regional variations in hydroclimatic conditions over Chile and to explore how basin behaviour is influenced by catchment attributes and water extractions. Further, CAMELS-CL enabled us to analyse biases and uncertainties in basin-wide precipitation and PET. The characterisation of catchment water balances revealed large discrepancies between precipitation products in arid regions and a systematic precipitation underestimation in headwater mountain catchments (high elevations and steep slopes) over humid regions. We evaluated PET products based on ground data and found a fairly good performance of both products in humid regions (r > 0.91) and lower correlation (r < 0.76) in hyper-arid regions. Further, the satellite-based PET showed a consistent overestimation of observation-based PET. Finally, we explored local anomalies in catchment response by analysing the relationship between hydrological signatures and an attribute characterising the level of anthropic interventions. We showed that larger anthropic interventions are correlated with lower than normal annual flows, runoff ratios, elasticity of runoff with respect to precipitation, and flashiness of runoff, especially in arid catchments. CAMELS-CL provides unprecedented information on catchments in a region largely underrepresented in large sample studies. This effort is part of an international initiative to create multi-national large sample datasets freely available for the community. CAMELS-CL can be visualised from http://camels.cr2.cl and downloaded from https://doi.pangaea.de/10.1594/PANGAEA.894885. |
| Climate change governance in the Anthropocene: Emergence of Polycentrism in Chile | Elem Sci Anth | Arriagada, R.; Aldunce, P.; Blanco, G.; Ibarra, C.; Moraga, P.; Nahuelhual, L.; O'Ryan, R.; Urquiza, A.; Gallardo, L. | 2018 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1525/elementa.329 | https://www.elementascience.org/article/10.1525/elementa.329/ | 68 | Vol: 6 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Multilateral efforts are essential to an effective response to climate change, but individual nations define climate action policy by translating local and global objectives into adaptation and mitigation actions. We propose a conceptual framework to explore opportunities for polycentric climate governance, understanding polycentricity as a property that encompasses the potential for coordinating multiple centers of semiautonomous decision-making. We assert that polycentrism engages a diverse array of public and private actors for a more effective approach to reducing the threat of climate change. In this way, polycentrism may provide an appropriate strategy for addressing the many challenges of climate governance in the Anthropocene. We review two Chilean case studies: Chile’s Nationally Determined Contribution on Climate Change and the Chilean National Climate Change Action Plan. Our examination demonstrates that Chile has included a diversity of actors and directed significant financial resources to both processes. The central government coordinated both of these processes, showing the key role of interventions at higher jurisdictional levels in orienting institutional change to improve strategic planning and better address climate change. Both processes also provide some evidence of knowledge co-production, while at the same time remaining primarily driven by state agencies and directed by technical experts. Efforts to overcome governance weaknesses should focus on further strengthening existing practices for climate change responses, establishing new institutions, and promoting decision-making that incorporates diverse social actors and multiple levels of governance. In particular, stronger inclusion of local level actors provides an opportunity to enhance polycentric modes of governance and improve climate change responses. Fully capitalizing on this opportunity requires establishing durable communication channels between different levels of governance. |
| Gene fusion of heterophyletic gamma-globin genes in platyrrhine primates | Journal of Genetics | Arroyo, J.; Nery, M. | 2018 | Zonas Costeras | 10.1007/s12041-018-1039-0 | http://link.springer.com/10.1007/s12041-018-1039-0 | 1473-1478 | Vol: 97 Issue: 5 | 0022-1333, 0973-7731 | Thomson Reuters ISI (SCIE) | English | We performed phylogenetic analyses of HBG genes to assess its origin and interspecific variation among primates. Our analyses showed variation in HBG genes copy number ranging from one to three, some of them pseudogenes. For platyrrhines HBG genes, phylogenetic reconstructions of flanking regions recovered orthologous clades with distinct topologies for 5′ and 3′ flanking regions. The 5′ region originated in the common ancestor of platyrrhines but the 3′ region had an anthropoid origin. We hypothesize that the platyrrhine HBG genes of 5′ and 3′ heterophyletic origins arose from subsequent fusions of the (earlier) platyrrhine 5′ portion and the (later) anthropoid 3′ portion. | |
| Burn severity controls on postfire Araucaria-Nothofagus regeneration in the Andean Cordillera | Journal of Biogeography | Assal, T.; González, M.; Sibold, J. | 2018 | Cambio de Uso de Suelo | 10.1111/jbi.13428 | http://doi.wiley.com/10.1111/jbi.13428 | 2483-2494 | Vol: 45 Issue: 11 | 0305-0270 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Aim: The aim of the study was to investigate postfire regeneration patterns of Araucaria-Nothofagus forests on the west slope of the Andes; to evaluate the relationship between remotely sensed burn severity and forest mortality; and to assess controls of burn severity on forest response at local spatio-temporal scales. Location: Araucanía region in the western Andean Range of south-central Chile where fire occurred during the 2001–2002 season. Methods: Sampling of prefire stand structure and postfire vegetation response was performed along a burn severity gradient a decade after the fire. We evaluated the relationship between field-measured tree mortality and satellite-derived burn severity using a generalized linear model. We fit zero-inflated mixture models to regeneration data of each genus to assess the importance of abiotic variables, stand characteristics, and biotic interactions. Results: The relative version of the delta Normalized Burn Ratio explained 85% of the variability in canopy mortality. Nearly 12,000 hectares burned; the majority at high severity (67%). Regeneration densities of both genera were lower at higher levels of burn severity and higher with greater total basal area (live, dead, and down trees). The relative effect size of burn severity on regeneration was nearly twice as large for Nothofagus, which suggests information legacies of Araucaria have cascading effects on postdisturbance material legacies. Main conclusions: Araucaria-Nothofagus mortality from wildfire can be readily mapped using satellite-derived burn severity. Although environmental site characteristics and biotic interactions mediate regeneration, basal area, and burn severity are the main mechanisms controlling regeneration. Forest refugia and postfire regeneration are vulnerable to recurrent fire. Therefore, we expect future fire (either increased severity or frequency), driven by landscape level changes, as a potential mechanism that can reduce local resilience of these forests as initial postfire material legacies (e.g., refugia and regeneration) are removed from the landscape. Our findings highlight an approach to quantify important attributes of forest disturbance and refugia, and identify areas for monitoring postdisturbance regeneration as the forests throughout south-central Chile and Argentina face a multitude of potential change agents. |
| Temporal and spatial evaluation of satellite rainfall estimates over different regions in Latin-America | Atmospheric Research | Baez-Villanueva, O.; Zambrano-Bigiarini, M.; Ribbe, L.; Nauditt, A.; Giraldo-Osorio, J.; Thinh, N. | 2018 | Agua y Extremos | 10.1016/j.atmosres.2018.05.011 | https://linkinghub.elsevier.com/retrieve/pii/S0169809517313029 | 34-50 | Vol: 213 | 01698095 | Thomson Reuters ISI (SCIE) | English | In developing countries, an accurate representation of the spatio-temporal variability of rainfall is currently severely limited, therefore, satellite-based rainfall estimates (SREs) are promising alternatives. In this work, six state-of-the-art SREs (TRMM 3B42v7, TRMM 3B42RT, CHIRPSv2, CMORPHv1, PERSIANN-CDR, and MSWEPv2) are evaluated over three different basins in Latin-America, using a point-to-pixel comparison at daily, monthly, and seasonal timescales. Three continuous (root mean squared error, modified Kling-Gupta efficiency, and percent bias) and three categorical (probability of detection, false alarm ratio, and frequency bias) indices are used to evaluate the performance of the different SREs, and to assess if the upscaling procedure used, in CHIRPSv2 and MSWEPv2, to enable a consistent point-to-pixel comparison affects the evaluation of the SREs performance at different time scales. Our results show that for Paraiba do Sul in Brazil, MSWEPv2 presented the best performance at daily and monthly time scales, while CHIRPSv2 performed the best at these timescales over the Magdalena River Basin in Colombia. In the Imperial River Basin in Chile, MSWEPv2 and CHIRPSv2 performed the best at daily and monthly time scales, respectively. When the basins were evaluated at seasonal scale, CMORPHv1 performed the best for DJF and SON, TRMM 3B42v7 for MAM, and PERSIANN-CDR for JJA over Imperial Basin. MSWEPv2 performed the best over Paraiba do Sul Basin for all seasons and CHIRPSv2 showed the best performance over Magdalena Basin. The Modified Kling-Gupta efficiency (KGE′) proved to be a useful evaluation index because it decomposes the performance of the SREs into linear correlation, bias, and variability parameters, while the Root Mean Squared Error (RMSE) is not recommended for evaluating SREs performance because it gives more weight to high rainfall events and its results are not comparable between areas with different precipitation regimes. On the other hand, CHIRPSv2 and MSWEPv2 presented different performance, for some study areas and time scales, when evaluated with their original spatial resolution (0.05° and 0.1, respectively) with respect to the evaluation resulting after applying the spatial upscaling (to a unified 0.25), showing that the upscaling procedure might impact the SRE performance. We finally conclude that a site-specific validation is needed before using any SRE, and we recommend to evaluate the SRE performance before and after applying any upscaling procedure in order to select the SRE that best represents the spatio-temporal precipitation patterns of a site. | |
| Recent intensification of Amazon flooding extremes driven by strengthened Walker circulation | Science Advances | Barichivich, J.; Gloor, E.; Peylin, P.; Brienen, R.; Schöngart, J.; Espinoza, J.; Pattnayak, K. | 2018 | Cambio de Uso de Suelo | 10.1126/sciadv.aat8785 | http://advances.sciencemag.org/lookup/doi/10.1126/sciadv.aat8785 | eaat8785 | Vol: 4 Issue: 9 | 2375-2548 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Amazon basin is the largest watershed on Earth. Although the variability of the Amazon hydrological cycle has been increasing since the late 1990s, its underlying causes have remained elusive. We use water levels in the Amazon River to quantify changes in extreme events and then analyze their cause. Despite continuing research emphasis on droughts, the largest change over recent decades is a marked increase in very severe floods. Increased flooding is linked to a strengthening of the Walker circulation, resulting from strong tropical Atlantic warming and tropical Pacific cooling. Atlantic warming due to combined anthropogenic and natural factors has contributed to enhance the change in atmospheric circulation. Whether this anomalous increase in flooding will last depends on the evolution of the tropical inter-ocean temperature difference. |
| The first 300-year streamflow reconstruction of a high-elevation river in Chile using tree rings: HIGH-ELEVATION CHILEAN RIVER STREAMFLOW RECONSTRUCTION | International Journal of Climatology | Barria, P.; Peel, M.; Walsh, K.; Muñoz, A. | 2018 | Agua y Extremos | 10.1002/joc.5186 | http://doi.wiley.com/10.1002/joc.5186 | 436-451 | Vol: 38 Issue: 1 | 0899-8418 | Thomson Reuters ISI (SCIE) | English | In central Chile, increasing demand for water and decreasing runoff volumes due to drier conditions have placed catchments in this zone under water stress. However, scarcity of observed data records increases the difficulty of planning future water supply. Instrumental records suggest a reduction in streamflow over the last 56 years. However, this change is not statistically significant and the lack of meteorological stations with long records in this mountainous region hampers a deeper analysis, motivating the use of tree rings to analyse whether these changes are part of a long-term trend. This work represents the first high-elevation runoff reconstruction in Chile using 300 years of tree ring chronologies of Araucaria araucana and Astroceudrus chilensis. The upper part of Biobío river melting season runoff (October–March) and pluvial season runoff (April–September) was reconstructed and analysed to investigate the influence of large-scale climatic drivers on runoff generation, current drought trends and to improve the understanding of climate variability in this region. We obtained positive correlations between the 20-year moving average of reconstructed pluvial season runoff and reconstructed Pacific Decadal Oscillation (PDO), which is indicative of multi-decadal variability. We also found a negative correlation between the 11-year moving average of reconstructed melting season runoff and the PDO and positive correlations with the Southern Annular Mode (SAM). Important differences in the runoff variability of the upper and the lower part of the catchment were identified which are in part led by the influence of the large-scale climatic features that drive runoff generation in both regions. We found that the changes observed in the instrumental records are part of multi-decadal cycles led by the PDO and SAM for pluvial season runoff and melting season runoff, respectively. | |
| Alternative approaches for estimating missing climate data: application to monthly precipitation records in South-Central Chile | Forest Ecosystems | Barrios, A.; Trincado, G.; Garreaud, R. | 2018 | Agua y Extremos | 10.1186/s40663-018-0147-x | https://forestecosyst.springeropen.com/articles/10.1186/s40663-018-0147-x | art: 28 | Vol: 5 Issue: 1 | 2197-5620 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Background Over the last decades interest has grown on how climate change impacts forest resources. However, one of the main constraints is that meteorological stations are riddled with missing climatic data. This study compared five approaches for estimating monthly precipitation records: inverse distance weighting (IDW), a modification of IDW that includes elevation differences between target and neighboring stations (IDWm), correlation coefficient weighting (CCW), multiple linear regression (MLR) and artificial neural networks (ANN). Methods A complete series of monthly precipitation records (1995–2012) from twenty meteorological stations located in central Chile were used. Two target stations were selected and their neighboring stations, located within a radius of 25 km (3 stations) and 50 km (9 stations), were identified. Cross-validation was used for evaluating the accuracy of the estimation approaches. The performance and predictive capability of the approaches were evaluated using the ratio of the root mean square error to the standard deviation of measured data (RSR), the percent bias (PBIAS), and the Nash-Sutcliffe efficiency (NSE). For testing the main and interactive effects of the radius of influence and estimation approaches, a two-level factorial design considering the target station as the blocking factor was used. Results ANN and MLR showed the best statistics for all the stations and radius of influence. However, these approaches were not significantly different with IDWm. Inclusion of elevation differences into IDW significantly improved IDWm estimates. In terms of precision, similar estimates were obtained when applying ANN, MLR or IDWm, and the radius of influence had a significant influence on their estimates, we conclude that estimates based on nine neighboring stations located within a radius of 50 km are needed for completing missing monthly precipitation data in regions with complex topography. Conclusions It is concluded that approaches based on ANN, MLR and IDWm had the best performance in two sectors located in south-central Chile with a complex topography. A radius of influence of 50 km (9 neighboring stations) is recommended for completing monthly precipitation data. |
| Status and future of numerical atmospheric aerosol prediction with a focus on data requirements | Atmospheric Chemistry and Physics | Benedetti, A.; Reid, J.; Knippertz, P.; Marsham, J.; Di Giuseppe, F.; Rémy, S.; Basart, S.; Boucher, O.; Brooks, I.; Menut, L.; Mona, L.; Laj, P.; Pappalardo, G.; Wiedensohler, A.; Baklanov, A.; Brooks, M.; Colarco, P.; Cuevas, E.; da Silva, A.; Escribano, J.; Flemming, J.; Huneeus, N.; Jorba, O.; K... | 2018 | Ciudades Resilientes | 10.5194/acp-18-10615-2018 | https://www.atmos-chem-phys.net/18/10615/2018/ | 10615-10643 | Vol: 18 Issue: 14 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Numerical prediction of aerosol particle properties has become an important activity at many research and operational weather centers. This development is due to growing interest from a diverse set of stakeholders, such as air quality regulatory bodies, aviation and military authorities, solar energy plant managers, climate services providers, and health professionals. Owing to the complexity of atmospheric aerosol processes and their sensitivity to the underlying meteorological conditions, the prediction of aerosol particle concentrations and properties in the numerical weather prediction (NWP) framework faces a number of challenges. The modeling of numerous aerosol-related parameters increases computational expense. Errors in aerosol prediction concern all processes involved in the aerosol life cycle including (a) errors on the source terms (for both anthropogenic and natural emissions), (b) errors directly dependent on the meteorology (e.g., mixing, transport, scavenging by precipitation), and (c) errors related to aerosol chemistry (e.g., nucleation, gas-aerosol partitioning, chemical transformation and growth, hygroscopicity). Finally, there are fundamental uncertainties and significant processing overhead in the diverse observations used for verification and assimilation within these systems. Indeed, a significant component of aerosol forecast development consists in streamlining aerosol-related observations and reducing the most important errors through model development and data assimilation. Aerosol particle observations from satellite- and ground-based platforms have been crucial to guide model development of the recent years and have been made more readily available for model evaluation and assimilation. However, for the sustainability of the aerosol particle prediction activities around the globe, it is crucial that quality aerosol observations continue to be made available from different platforms (space, near surface, and aircraft) and freely shared. This paper reviews current requirements for aerosol observations in the context of the operational activities carried out at various global and regional centers. While some of the requirements are equally applicable to aerosol-climate, the focus here is on global operational prediction of aerosol properties such as mass concentrations and optical parameters. It is also recognized that the term "requirements" is loosely used here given the diversity in global aerosol observing systems and that utilized data are typically not from operational sources. Most operational models are based on bulk schemes that do not predict the size distribution of the aerosol particles. Others are based on a mix of "bin" and bulk schemes with limited capability of simulating the size information. However the next generation of aerosol operational models will output both mass and number density concentration to provide a more complete description of the aerosol population. A brief overview of the state of the art is provided with an introduction on the importance of aerosol prediction activities. The criteria on which the requirements for aerosol observations are based are also outlined. Assimilation and evaluation aspects are discussed from the perspective of the user requirements. |
| Economía de la Pobreza Energética ¿Por qué y cómo garantizar un acceso universal y equitativo a la energía? | Economía y Política | Billi, M.; Amigo, C.; Calvo, R.; Urquiza, A. | 2018 | Ciudades Resilientes | 10.15691./07194714.2018.006 | http://www.economiaypolitica.cl/index.php/eyp/article/view/58/63 | 35-65 | Vol: 5 | 0719-4803 | Scopus | Spanish | The aspiration to guarantee a universal and equitable access to modern and nonpolluting energies, and specifically the notion of ‘energy poverty’, have lately been gaining increasing relevance as objectives of social policy. However, there lacks a profound reflection on the economic justifications and considerations that could motivate and guide public initiatives in this direction, especially for what concerns Chile. Although the existence of failures in the private provision of energy can lay the foundations for a public intervention in the sector, they are not enough to justify minimum consumption standards as those required by the idea of e nergy poverty. Such standards, on the contrary, are consistent with an understanding of energy as a merit good, a good whose consumption should be propitiated independently of the preferences of its beneficiaries. The above observation is enhanced considering the growing emphasis placed by the specialized literature on transiting from definitions of energy poverty limited to the lack of economic or technological opportunities for the access to energy, towards more comprehensive and multidimensional understandings of the phenomenon. Within the latter, energy poverty must be understood in relation with the effective capacity of every person and household to access energy services adequate to meet their needs. In turn, this places a new emphasis on the equalization of the effective benefits that energy provides to its users –as opposed to, the mere equalization of the opportunity of gaining access to the energy services that the market provides. This shift in attention should lead to give increased relevance to the incorporation of recent findings from behavioural economics, regarding the understanding and intervention of the contexts, habits and consumption decisions from which those benefits depend. | |
| Anthropogenic drying in central-southern Chile evidenced by long-term observations and climate model simulations | Elementa: Science of the Anthropocene | Boisier, J.; Alvarez-Garretón, C.; Cordero, R.; Damiani, A.; Gallardo, L.; Garreaud, R.; Lambert, F.; Ramallo, C.; Rojas, M.; Rondanelli, R. | 2018 | Agua y Extremos; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | 10.1525/elementa.328 | https://www.elementascience.org/article/10.1525/elementa.328/ | 74 | Vol: 6 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The socio-ecological sensitivity to water deficits makes Chile highly vulnerable to global change. New evidence of a multi-decadal drying trend and the impacts of a persistent drought that since 2010 has affected several regions of the country, reinforce the need for clear diagnoses of the hydro-climate changes in Chile. Based on the analysis of long-term records (50+ years) of precipitation and streamflow, we confirm a tendency toward a dryer condition in central-southern Chile (30–48°S). We describe the geographical and seasonal character of this trend, as well as the associated large-scale circulation pat- terns. When a large ensemble of climate model simulations is contrasted to observations, anthropogenic forcing appears as the leading factor of precipitation change. In addition to a drying trend driven by greenhouse gas forcing in all seasons, our results indicate that the Antarctic stratospheric ozone deple- tion has played a major role in the summer rainfall decline. Although average model results agree well with the drying trend’s seasonal character, the observed change magnitude is two to three times larger than that simulated, indicating a potential underestimation of future projections for this region. Under present-day carbon emission rates, the drying pathway in Chile will likely prevail during the next decades, although the summer signal should weaken as a result of the gradual ozone layer recovery. The trends and scenarios shown here pose substantial stress on Chilean society and its institutions, and call for urgent action regarding adaptation measures. |
| Projected hydroclimate changes over Andean basins in central Chile from downscaled CMIP5 models under the low and high emission scenarios | Climatic Change | Bozkurt, D.; Rojas, M.; Boisier, J.; Valdivieso, J. | 2018 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.1007/s10584-018-2246-7 | http://link.springer.com/10.1007/s10584-018-2246-7 | 131-147 | Vol: 150 Issue: 3-4 | 0165-0009 | Thomson Reuters ISI (SCIE) | English | This study examines the projections of hydroclimatic regimes and extremes over Andean basins in central Chile (approximate to 30-40 degrees S) under a low and high emission scenarios (RCP2.6 and RCP8.5, respectively). A gridded daily precipitation and temperature dataset based on observations is used to drive and validate the VIC macro-scale hydrological model in the region of interest. Historical and future simulations from 19 climate models participating in CMIP5 have been adjusted with the observational dataset and then used to make hydrological projections. By the end of the century, there is a large difference between the scenarios, with projected warming of approximate to + 1.2 degrees C (RCP2.6), approximate to +3.5 degrees C (RCP8.5) and drying of approximate to - 3% (RCP2.6), approximate to - 30% (RCP8.5). Following the strong drying and warming projected in this region under the RCP8.5 scenario, the VIC model simulates decreases in annual runoff of about 40% by the end of the century. Such strong regional effect of climate change may have large implications for the water resources of this region. Even under the low emission scenario, the Andes snowpack is projected to decrease by 35-45% by mid-century. In more snowmelt-dominated areas, the projected hydrological changes under RCP8.5 go together with more loss in the snowpack (75-85%) and a temporal shift in the center timing of runoff to earlier dates (up to 5 weeks by the end of the century). The severity and frequency of extreme hydroclimatic events are also projected to increase in the future. The occurrence of extended droughts, such as the recently experienced mega-drought (2010-2015), increases from one to up to five events per 100 years under RCP8.5. Concurrently, probability density function of 3-day peak runoff indicates an increase in the frequency of flood events. The estimated return periods of 3-day peak runoff events depict more drastic changes and increase in the flood risk as higher recurrence intervals are considered by mid-century under RCP2.6 and RCP8.5, and by the end of the century under RCP8.5. | |
| Foehn Event Triggered by an Atmospheric River Underlies Record-Setting Temperature Along Continental Antarctica | Journal of Geophysical Research: Atmospheres | Bozkurt, D.; Rondanelli, R.; Marín, J.; Garreaud, R. | 2018 | Agua y Extremos; Zonas Costeras | 10.1002/2017JD027796 | http://doi.wiley.com/10.1002/2017JD027796 | 3871-3892 | Vol: 123 Issue: 8 | 2169-897X | Thomson Reuters ISI (SCIE) | English | A record‐setting temperature of 17.5°C occurred on 24 March 2015 at the Esperanza station located near the northern tip of the Antarctic Peninsula (AP). We studied the event using surface station data, satellite imagery, reanalysis data, and numerical simulations. The Moderate Resolution Imaging Spectroradiometer Antarctic Ice Shelf Image Archive provides clear evidence for disintegration and advection of sea ice, as well as the formation of melt ponds on the ice sheet surface at the base of the AP mountain range. A deep low‐pressure center over the Amundsen‐Bellingshausen Sea and a blocking ridge over the southeast Pacific provided favorable conditions for the development of an atmospheric river with a northwest‐southeast orientation, directing warm and moist air toward the AP, and triggering a widespread foehn episode. A control simulation using a regional climate model shows the existence of local topographically induced warming along the northern tip of the AP (∼60% of the full temperature signal) and the central part of the eastern AP (>90% of the full temperature signal) with respect to a simulation without topography. These modeling results suggest that more than half of the warming experienced at Esperanza can be attributed to the foehn effect (a local process), rather than to the large‐scale advection of warm air from the midlatitudes. Nevertheless, the local foehn effect also has a large‐scale advection component, since the atmospheric river provides water vapor for orographic precipitation enhancement and latent heat release, which makes it difficult to completely disentangle the role of local versus large‐scale processes in explaining the extreme event. | |
| Tree rings reveal globally coherent signature of cosmogenic radiocarbon events in 774 and 993 CE | Nature Communications | Büntgen, U.; Wacker, L.; Galván, J.; Arnold, S.; Arseneault, D.; Baillie, M.; Beer, J.; Bernabei, M.; Bleicher, N.; Boswijk, G.; Bräuning, A.; Carrer, M.; Ljungqvist, F.; Cherubini, P.; Christl, M.; Christie, D.; Clark, P.; Cook, E.; D’Arrigo, R.; Davi, N.; Eggertsson, Ó.; Esper, J.; Fowler, A.; Ged... | 2018 | Agua y Extremos; Cambio de Uso de Suelo | 10.1038/s41467-018-06036-0 | http://www.nature.com/articles/s41467-018-06036-0 | art: 3605 | Vol: 9 Issue: 1 | 2041-1723 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Though tree-ring chronologies are annually resolved, their dating has never been independently validated at the global scale. Moreover, it is unknown if atmospheric radiocarbon enrichment events of cosmogenic origin leave spatiotemporally consistent fingerprints. Here we measure the 14C content in 484 individual tree rings formed in the periods 770–780 and 990–1000 CE. Distinct 14C excursions starting in the boreal summer of 774 and the boreal spring of 993 ensure the precise dating of 44 tree-ring records from five continents. We also identify a meridional decline of 11-year mean atmospheric radiocarbon concentrations across both hemispheres. Corroborated by historical eye-witness accounts of red auroras, our results suggest a global exposure to strong solar proton radiation. To improve understanding of the return frequency and intensity of past cosmic events, which is particularly important for assessing the potential threat of space weather on our society, further annually resolved 14C measurements are needed. |
| Self-organizing processes in urban green commons. The case of the Angachilla wetland, Valdivia-Chile | International Journal of the Commons | Correa, H.; Blanco-Wells, G.; Barrena, J.; Tacón, A. | 2018 | Gobernanza e Interfaz Ciencia y Política | 10.18352/ijc.856 | https://www.thecommonsjournal.org/articles/10.18352/ijc.856 | 573-595 | Vol: 12 Issue: 1 | 1875-0281 | Thomson Reuters ISI (SSCI) | All Open Access; Gold Open Access | English | This article focuses on self-organizing processes in contested urban social-ecological systems. It analyzes a wetland conservation program and civic management effort in the Angachilla sector of the city of Valdivia, Chile in a 15-year time frame. The aim is to understand what triggers collective actions and self-organization in the attempts of preserving an urban green common. The study uses a qualitative approach based on action-research methodologies. It examines key variables influencing self-organizing processes; including social-environmental crises, governance vacuums, wetland valuation, and leadership. It also discusses collective strategies for the transformation of negative feedback loops, such as norms and regulations detrimental to wetland protection, and those related to resistance to change of wetland surface area due to unregulated urbanization. From an Urban Green Commons perspective, this work illustrates the complexity of dealing with contested nature, making it a resource difficult to govern collectively given all the different interests and values in place. It also shows that there have been successful periods of active wetland management that have influenced active democratic processes regarding land use and land use change in the city. |
| An unusual kind of diurnal streamflow variation | Journal of Hydrology and Hydromechanics | Cuevas, J.; Arumí, J.; Zúñiga-Feest, A.; Little, C. | 2018 | Cambio de Uso de Suelo | 10.1515/johh-2017-0041 | http://www.degruyter.com/view/j/johh.2018.66.issue-1/johh-2017-0041/johh-2017-0041.xml | 32-42 | Vol: 66 Issue: 1 | 0042-790X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | During hydrological research in a Chilean swamp forest, we noted a pattern of higher streamflows close to midday and lower ones close to midnight, the opposite of an evapotranspiration (Et)-driven cycle. We analyzed this diurnal streamflow signal (DSS), which appeared mid-spring (in the growing season). The end of this DSS coincided with a sustained rain event in autumn, which deeply affected stream and meteorological variables. A survey along the stream revealed that the DSS maximum and minimum values appeared 6 and 4 hours earlier, respectively, at headwaters located in the mountain forests/ plantations than at the control point in the swamp forest. Et in the swamp forest was higher in the morning and in the late afternoon, but this process could not influence the groundwater stage. Trees in the mountain headwaters reached their maximum Ets in the early morning and/or close to midday. Our results suggest that the DSS is a wave that moves from forests high in the mountains towards lowland areas, where Et is decoupled from the DSS. This signal delay seems to convert the link between streamflow and Et in an apparent, but spurious positive relationship. It also highlights the role of landscape heterogeneity in shaping hydrological processes. |
| Nutrient and sediment losses to streams after intervention of eucalyptus plantations | Journal of Soil Science and Plant Nutrition | Cuevas, J.; Little, C.; Lobos, D.; Lara, A.; Pino, M.; Acuña, A. | 2018 | Cambio de Uso de Suelo | 10.4067/S0718-95162018005001702 | https://doi.org/10.4067/S0718-95162018005001702 | 576-596 | Vol: 18 Issue: 2 | 0718-9516 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access; Hybrid Gold Open Access | English | The forestry industry is known for negatively affecting stream quality when proper management is not applied. Nutrient retention by soils and streamside vegetation buffer strips could attenuate these impacts. We tested the response of different streams to the nutrients and sediments released by a) fertilization and b) clear-cutting of Eucalyptus globulus plantations growing on volcanic soils in southern Chile. We expected the exports to decrease as the remnant streamside native forest width (SNFW) increased. The response to fertilization was restricted to the days immediately after the nutrient addition. On the contrary, most of the nutrients analysed (nitrate, ammonium, dissolved organic nitrogen, phosphate, and total phosphorus) showed a long-term response to clear-cutting. The observed trends were not affected by the SNFWs included in this study (2.5-22 m). Regarding sediments, there were no differences compared to the control watershed, probably due to improvements in the implemented management practices. We conclude that a SNFW < 22 m is not sufficient to avoid the loss of nutrients released by clear-cutting, as it is for sediments. The analysed SNFWs were smaller than those established by Chilean regulations (maximum 30 m) and our results support claims for wider riparian widths in order to effectively filter the nutrients and sediments that influence streams. © 2018, Sociedad Chilena de la Ciencia del Suelo. All rights reserved. |
| Local and remote black carbon sources in the Metropolitan Area of Buenos Aires | Atmospheric Environment | Diaz Resquin, M.; Santágata, D.; Gallardo, L.; Gómez, D.; Rössler, C.; Dawidowski, L. | 2018 | Ciudades Resilientes | 10.1016/j.atmosenv.2018.03.018 | http://linkinghub.elsevier.com/retrieve/pii/S1352231018301560 | 105-114 | Vol: 182 | 1352-2310 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Equivalent black carbon () mass concentrations in the fine inhalable fraction of airborne particles () were determined using a 7-wavelength Aethalometer for 17 months, between November 2014 and March 2016, for a suburban location of the Metropolitan Area of Buenos Aires (MABA), Argentina. In addition to describing seasonal and diurnal black carbon (BC) cycles for the first time in this region, the relative contributions of fossil fuel and remote and local biomass burning were determined by distinguishing different carbonaceous components based on their effect on light attenuation for different wavelengths. Trajectory analyses and satellite-based fire products were used to illustrate the impact of long-range transport of particles emitted by non-local sources. EBC data showed a marked diurnal cycle, largely modulated by traffic variations and the height of the boundary layer, and a seasonal cycle with monthly median EBC concentrations (in ) ranging from 1.5 (February) to 3.4 (June). Maximum values were found during winter due to the combination of prevailingly stable atmospheric conditions and the increase of fossil fuel emissions, derived primarily from traffic and biomass burning from the domestic use of wood for heating. The use of charcoal grills was also detected and concentrated during weekends. The average contribution of fossil fuel combustion sources to concentrations was 96%, with the remaining 4% corresponding to local and regional biomass burning. During the entire study period, only two events were identified during which concentrations attributed to regional biomass burning accounted for over 50% of total ; these events demonstrate the relevance of agricultural and forestry activities that take place far from the city yet whose emissions can affect the urban atmosphere of the MABA. |
| Teleconnection stationarity, variability and trends of the Southern Annular Mode (SAM) during the last millennium | Climate Dynamics | Dätwyler, C.; Neukom, R.; Abram, N.; Gallant, A.; Grosjean, M.; Jacques-Coper, M.; Karoly, D.; Villalba, R. | 2018 | Zonas Costeras | 10.1007/s00382-017-4015-0 | http://link.springer.com/10.1007/s00382-017-4015-0 | 2321-2339 | Vol: 51 Issue: 5-6 | 0930-7575, 1432-0894 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The Southern Annular Mode (SAM) is the leading mode of atmospheric interannual variability in the Southern Hemisphere (SH) extra-tropics. Here, we assess the stationarity of SAM spatial correlations with instrumental and paleoclimate proxy data for the past millennium. The instrumental period shows that temporal non-stationarities in SAM teleconnections are not consistent across the SH land areas. This suggests that the influence of the SAM index is modulated by regional effects. However, within key-regions with good proxy data coverage (South America, Tasmania, New Zealand), teleconnections are mostly stationary over the instrumental period. Using different stationarity criteria for proxy record selection, we provide new austral summer and annual mean SAM index reconstructions over the last millennium. Our summer SAM reconstructions are very robust to changes in proxy record selection and the selection of the calibration period, particularly on the multi-decadal timescale. In contrast, the weaker performance and lower agreement in the annual mean SAM reconstructions point towards changing teleconnection patterns that may be particularly important outside the summer months. Our results clearly portend that the temporal stationarity of the proxy-climate relationships should be taken into account in the design of comprehensive regional and hemispherical climate reconstructions. The summer SAM reconstructions show no significant relationship to solar, greenhouse gas and volcanic forcing, with the exception of an extremely strong negative anomaly following the AD 1257 Samalas eruption. Furthermore, reconstructed pre-industrial summer SAM trends are very similar to trends obtained by model control simulations. We find that recent trends in the summer SAM lie outside the 5–95% range of pre-industrial natural variability. |
| Distribution of dissolved methane and nitrous oxide in Chilean coastal systems of the Magellanic Sub-Antarctic region (50°–55°S) | Estuarine, Coastal and Shelf Science | Farías, L.; Bello, E.; Arancibia, G.; Fernandez, J. | 2018 | Zonas Costeras | 10.1016/j.ecss.2018.10.020 | https://linkinghub.elsevier.com/retrieve/pii/S0272771418304785 | 229-240 | Vol: 215 | 0272-7714 | Thomson Reuters ISI (SCIE) | English | Nitrous oxide (N2O) and methane (CH4) are greenhouse gases and active in the depletion of the ozone layer. These gases, originating from both anthropogenic and natural sources, are mainly released to the atmosphere from coastal areas, including continental shelves, estuaries and fjords. Surface distribution of dissolved N2O and CH4 during the austral spring were described within the Magellanic Sub-Antarctic region (50–55°S, Chile) with a coastal area that has a complex system of fjords, channels, gulf and, bays. A narrow range of N2O concentrations were observed from under-saturations (∼65%), as result of freshwater/glacial flow into fjord heads, to slight super-saturations (∼120–150%) in fjord mouths and adjacent marine zones. One exception was Otway Sound, where a penguin colony is situated, with N2O levels of up to 218%. In contrast, CH4 concentrations presented a wide range of saturations between 47.9% and 483%, with a spatial distribution that mainly corresponded to the type of hydrographic/geomorphologic basin; in the southern Patagonian Andes (mostly covered by the southern Ice Fields) CH4 levels varied between 65 and 80% in the marine area, and 180% saturation in the channels and fjords; whereas in the southern Patagonian tableland (Magellan Strait) higher CH4 concentrations, up to 483% saturation, were observed apparently associated with continental inputs (peatland and tundra vegetation). N2O concentrations were positively correlated with salinity and nutrients, indicating that the majority of N2O and nutrients (except silicate) originated from the Sub-Antarctic Water Mass (SAAW), which mixes with N2O-depleated freshwater. However, CH4 concentrations did not correlate with any oceanographic variables, suggesting that they originate from local marine/terrestrial interactions. The Magellanic Sub-Antarctic region acts as a modest source of N2O and CH4, to the atmosphere with effluxes of 6.20 ± 10.13 and 16.88 ± 27.04 μmol m−2 d−1 respectively. Due to climate change and a growth in anthropogenic activities such as salmon farming, future emissions of N2O and CH4 within this remote region remain uncertain. | |
| New insights into the use of stable water isotopes at the northern Antarctic Peninsula as a tool for regional climate studies | The Cryosphere | Fernandoy, F.; Tetzner, D.; Meyer, H.; Gacitúa, G.; Hoffmann, K.; Falk, U.; Lambert, F.; MacDonell, S. | 2018 | Ciudades Resilientes | 10.5194/tc-12-1069-2018 | https://www.the-cryosphere.net/12/1069/2018/ | 1069-1090 | Vol: 12 Issue: 3 | 1994-0424 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Due to recent atmospheric and oceanic warming, the Antarctic Peninsula is one of the most challenging regions of Antarctica to understand in terms of both local- and regional-scale climate signals. Steep topography and a lack of long-term and in situ meteorological observations complicate the extrapolation of existing climate models to the sub-regional scale. Therefore, new techniques must be developed to better understand processes operating in the region. Isotope signals are traditionally related mainly to atmospheric conditions, but a detailed analysis of individual components can give new insight into oceanic and atmospheric processes. This paper aims to use new isotopic records collected from snow and firn cores in conjunction with existing meteorological and oceanic datasets to determine changes at the climatic scale in the northern extent of the Antarctic Peninsula. In particular, a discernible effect of sea ice cover on local temperatures and the expression of climatic modes, especially the Southern Annular Mode (SAM), is demonstrated. In years with a large sea ice extension in winter (negative SAM anomaly), an inversion layer in the lower troposphere develops at the coastal zone. Therefore, an isotope–temperature relationship (δ–T) valid for all periods cannot be obtained, and instead the δ–T depends on the seasonal variability of oceanic conditions. Comparatively, transitional seasons (autumn and spring) have a consistent isotope–temperature gradient of +0.69 ‰ °C−1. As shown by firn core analysis, the near-surface temperature in the northern-most portion of the Antarctic Peninsula shows a decreasing trend (−0.33 °C year−1) between 2008 and 2014. In addition, the deuterium excess (dexcess) is demonstrated to be a reliable indicator of seasonal oceanic conditions, and therefore suitable to improve a firn age model based on seasonal dexcess variability. The annual accumulation rate in this region is highly variable, ranging between 1060 and 2470 kg m−2 year−1 from 2008 to 2014. The combination of isotopic and meteorological data in areas where data exist is key to reconstruct climatic conditions with a high temporal resolution in polar regions where no direct observations exist. |
| Dendrohydrology and water resources management in south-central Chile: lessons from the Río Imperial streamflow reconstruction | Hydrology and Earth System Sciences | Fernández, A.; Muñoz, A.; González-Reyes, Á.; Aguilera-Betti, I.; Toledo, I.; Puchi, P.; Sauchyn, D.; Crespo, S.; Frene, C.; Mundo, I.; González, M.; Vignola, R. | 2018 | Agua y Extremos | 10.5194/hess-22-2921-2018 | https://www.hydrol-earth-syst-sci.net/22/2921/2018/ | 2921-2935 | Vol: 22 Issue: 5 | 1607-7938 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Streamflow in south-central Chile (SCC, ∼ 37–42° S) is vital for agriculture, forestry production, hydroelectricity, and human consumption. Recent drought episodes have generated hydrological deficits with damaging effects on these activities. This region is projected to undergo major reductions in water availability, concomitant with projected increases in water demand. However, the lack of long-term records hampers the development of accurate estimations of natural variability and trends. In order to provide more information on long-term streamflow variability and trends in SCC, here we report findings of an analysis of instrumental records and a tree-ring reconstruction of the summer streamflow of the Río Imperial ( ∼ 37° 40′ S–38° 50′ S). This is the first reconstruction in Chile targeted at this season. Results from the instrumental streamflow record ( ∼ 1940 onwards) indicated that the hydrological regime is fundamentally pluvial with a small snowmelt contribution during spring, and evidenced a decreasing trend, both for the summer and the full annual record. The reconstruction showed that streamflow below the average characterized the post-1980 period, with more frequent, but not more intense, drought episodes. We additionally found that the recent positive phase of the Southern Annular Mode has significantly influenced streamflow. These findings agree with previous studies, suggesting a robust regional signal and a shift to a new hydrological scenario. In this paper, we also discuss implications of these results for water managers and stakeholders; we provide rationale and examples that support the need for the incorporation of tree-ring reconstructions into water resources management. |
| d 18 O of Fissurella maxima as a proxy for reconstructing Early Holocene sea surface temperatures in the coastal Atacama desert (25S) | Palaeogeography, Palaeoclimatology, Palaeoecology | Flores, C.; Gayo, E.; Salazar, D.; Broitman, B. | 2018 | Ciudades Resilientes | 10.1016/j.palaeo.2018.03.031 | http://linkinghub.elsevier.com/retrieve/pii/S003101821730874X | 22-34 | Vol: 499 | 0031-0182 | Thomson Reuters ISI (SCIE) | English | Fissurella maxima is a keyhole limpet that is abundant and well preserved in archaeological shell midden sites along the coast of Chile, making it an appropriate species to use for reconstructions of past sea surface temperature (SST). In the present study we evaluate the potential of F. maxima shells as a proxy of SST by analysing δ18O of modern shells collected alive from the Atacama desert (area of Taltal, 25°S) and archaeological shells from two Early Holocene rockshelter sites: 224A and Paposo Norte 9. Reconstructed SST from modern F. maxima shells were related to SST obtained from in situ thermometers, supporting the use of this mollusc species as a paleotemperature archive. Mean SST reconstructed from Early Holocene archaeological shells (14.13 °C) was 2.86 °C cooler than mean temperature recorded in modern shells (16.99 °C). Mean SST reconstructed from modern shells was ~1.04 °C warmer than the mean temperature of in situ thermometers (15.95°C). Hence the paleo–SST data from archaeological sites 224A and Paposo Norte 9 enrich the Early Holocene nearshore paleoceanographic scenario of the Pacific coast of South America, with mean SST cooler than present-day SST. Our results validate the use of F. maxima shells as a SST proxy and contribute to a better understanding of the latitudinal distribution of the coastal upwelling regime during the Early Holocene, temporal changes in the structure of the Humboldt Current along the Holocene, and its influence on human adaptation through the prehistory of South America. | |
| The cascade impacts of climate change could threaten key ecological interactions | Ecosphere | Fontúrbel, F.; Lara, A.; Lobos, D.; Little, C. | 2018 | Cambio de Uso de Suelo | 10.1002/ecs2.2485 | https://onlinelibrary.wiley.com/doi/abs/10.1002/ecs2.2485 | e02485 | Vol: 9 Issue: 12 | 2150-8925 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Climate change is triggering ecological responses all over the world as a result of frequent, prolonged droughts. It could also affect ecological interactions, particularly pollination and seed dispersal, which play a key role in plant reproduction. We used a tripartite interaction with a mistletoe, its pollinator and its disperser animals to gain insight into this issue. We studied flower and fruit production, and visitation rates during average (2012) and dry (2015) austral summers. Drought in our study area affected precipitation and soil water availability. Although pollinator visits did not significantly differ in these summers, during the dry summer flower and fruit production experienced an important decline, as did seed disperser visits. Also, mistletoe mortality increased from 12% in 2012 to 23% in 2015. This empirical evidence suggests that the cascade effects of climate change may indirectly be hindering ecological interactions in the Valdivian temperate rainforest ecosystem we studied. Long‐term research is essential to provide the knowledge necessary to understand how key ecological processes may be affected in a changing world. |
| Synchronization of energy consumption by human societies throughout the Holocene | Proceedings of the National Academy of Sciences | Freeman, J.; Baggio, J.; Robinson, E.; Byers, D.; Gayo, E.; Finley, J.; Meyer, J.; Kelly, R.; Anderies, J. | 2018 | Ciudades Resilientes | 10.1073/pnas.1802859115 | http://www.pnas.org/lookup/doi/10.1073/pnas.1802859115 | 9962-9967 | Vol: 115 Issue: 40 | 0027-8424 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access; Hybrid Gold Open Access | English | We conduct a global comparison of the consumption of energy by human populations throughout the Holocene and statistically quantify coincident changes in the consumption of energy over space and time—an ecological phenomenon known as synchrony. When populations synchronize, adverse changes in ecosystems and social systems may cascade from society to society. Thus, to develop policies that favor the sustained use of resources, we must understand the processes that cause the synchrony of human populations. To date, it is not clear whether human societies display long-term synchrony or, if they do, the potential causes. Our analysis begins to fill this knowledge gap by quantifying the long-term synchrony of human societies, and we hypothesize that the synchrony of human populations results from (i) the creation of social ties that couple populations over smaller scales and (ii) much larger scale, globally convergent trajectories of cultural evolution toward more energy-consuming political economies with higher carrying capacities. Our results suggest that the process of globalization is a natural consequence of evolutionary trajectories that increase the carrying capacities of human societies. |
| Evolution of air quality in Santiago: The role of mobility and lessons from the science-policy interface | Elem Sci Anth | Gallardo, L.; Barraza, F.; Ceballos, A.; Galleguillos, M.; Huneeus, N.; Lambert, F.; Ibarra, C.; Munizaga, M.; O'Ryan, R.; Osses, M.; Tolvett, S.; Urquiza, A.; Véliz, K. | 2018 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1525/elementa.293 | https://www.elementascience.org/article/10.1525/elementa.293/ | 38 | Vol: 6 Issue: 1 | 2325-1026 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Worldwide, urbanization constitutes a major and growing driver of global change and a distinctive feature of the Anthropocene. Thus, urban development paths present opportunities for technological and societal transformations towards energy efficiency and decarbonization, with benefits for both greenhouse gas (GHG) and air pollution mitigation. This requires a better understanding of the intertwined dynamics of urban energy and land use, emissions, demographics, governance, and societal and biophysical processes. In this study, we address several characteristics of urbanization in Santiago (33.5°S, 70.5°W, 500 m a.s.l.), the capital city of Chile. Specifically, we focus on the multiple links between mobility and air quality, describe the evolution of these two aspects over the past 30 years, and review the role scientific knowledge has played in policy-making. We show evidence of how technological measures (e.g., fuel quality, three-way catalytic converters, diesel particle filters) have been successful in decreasing coarse mode aerosol (PM10) concentrations in Santiago despite increasing urbanization (e.g., population, motorization, urban sprawl). However, we also show that such measures will likely be insufficient if behavioral changes do not achieve an increase in the use of public transportation. Our investigation seeks to inform urban development in the Anthropocene, and our results may be useful for other developing countries, particularly in Latin America and the Caribbean where more than 80% of the population is urban. |
| A plausible atmospheric trigger for the 2017 coastal El Niño: THE 2017 COASTAL EL NIÑO | International Journal of Climatology | Garreaud, R. | 2018 | Agua y Extremos | 10.1002/joc.5426 | http://doi.wiley.com/10.1002/joc.5426 | e1296-e1302 | Vol: 38 | 0899-8418 | Thomson Reuters ISI (SCIE) | English | The far eastern tropical Pacific experienced a rapid, marked warming in early 2017, causing torrential rains along the west coast of South America with a significant societal toll in Peru and Ecuador. This strong coastal El Niño was largely unpredicted, even a few weeks before its onset, and it developed differently from either central or eastern events. Here we provide an overview of the event, its impacts and concomitant atmospheric circulation. It is proposed that a remotely forced, sustained weakening of the free tropospheric westerly flow impinging the subtropical Andes leads to a relaxation of the southeasterly (SE) trades off the coast, which in turn may have warmed the eastern Pacific throughout the weakening of upwelling in a near-coastal band and the lessening of the evaporative cooling farther offshore. | |
| Record-breaking climate anomalies lead to severe drought and environmental disruption in western Patagonia in 2016 | Climate Research | Garreaud, R. | 2018 | Agua y Extremos | 10.3354/cr01505 | http://www.int-res.com/abstracts/cr/v74/n3/p217-229/ | 217-229 | Vol: 74 Issue: 3 | 0936-577X | Thomson Reuters ISI (SCIE) | English | Traditionally a temperate and hyper-humid region, western Patagonia experienced its most severe drought during the summer and fall of 2016. Along with precipitation deficits larger than 50% there was a similar reduction in river discharge into coastal waters, a decline in vegetation productivity, excessive solar radiation at the surface, and frequent upwelling-favorable wind events offshore. The combination of these regional-scale anomalies seems to have set the stage for environmental disturbances that, although not new in western Patagonia, occurred with unprecedented magnitude, including severe urban air pollution episodes, large forest fires, and the worst ever recorded harmful algae bloom (HAB). The local climate anomalies were in turn related to the concomitant strong El Niño (through atmospheric teleconnections) and, to a lesser extent, anthropogenic climate change mediated by the positive polarity of the Southern Annular Mode (SAM) and internal variability, as both modes weakened the westerlies. Dryer than present conditions are consistently projected for northern Patagonia during the 21st century as a consequence of anthropogenic increases in radiative forcing; superposition of El Niño events in this altered climate may result in a higher frequency of extreme droughts and environmental disruptions like those observed in 2016. | |
| Tres niños sorprendentes | Boletín Técnico Instituto de Geofísica del Perú (IGP) | Garreaud, R. | 2018 | Agua y Extremos | http://intranet.igp.gob.pe/sysppr/results/result_71/Boletin_Tecnico_PPR_El_Nino_IGP_201801.pdf | 5-9 | Vol: 5 Issue: 1 | Aunque el fenómeno de El Niño–Oscilación del Sur (ENOS) se desarrolla en el Pacífico tropical, las alteraciones climáticas durante sus fases extremas (El Niño y La Niña) se extienden a gran parte del planeta (Diaz & Markgraf, 2000). No es sorprendente entonces que ENOS ha atraído la atención de la comunidad científica por más de un siglo, culminando en una teoría que describe su desarrollo y decaimiento (e.g., Neelin et al., 1998), justificando el establecimiento de la red de observaciones TAO-Triton y motivando el desarrollo de la predicción climática estacional en base a modelos estadísticos y dinámicos. No obstante estos avances científicos y tecnológico y nuestra capacidad de predecir la ocurrencia de eventos Tres Niños Sorprendentes Dr. René Garreaud S. SUBDIRECTOR DEL CENTRO DE INVESTIGACIÓN DEL CLIMA Y LA RESILIENCIA (CR2). Doctor en Ciencias Atmosféricas de la Universidad de Washington, EE.UU., Magister en Geofísica e Ingeniero de la Universidad de Chile. Es autor de más de 80 artículos publicados en revistas internacionales y su investigación está enfocada en la dinámica del clima y meteorología de Sudamérica. Dicta regularmente cursos de pre y posgrado en Climatología, y ha supervisado 10 postdocs. Se ha desempeñado también como presidente del consejo superior de ciencias (FONDECYT Chile) y presidente de la comisión de evaluación de la Facultad de Ciencias Físicas y Matemáticas de la Universidad de Chile. El Niño y La Niña es aun limitada, similar a la que presentaban los pronósticos del tiempo hace unos 30 años atrás (Barnston et al., 2012). En la última década se ha reconocido además la gran diversidad de eventos, los que no solo difieren en su intensidad y estructura sino que también en los mecanismos subyacentes (e.g., Takahashi et al., 2011; Takahashi & Dewitte 2016). Así, ENOS no deja de sorprendernos y algunos eventos exhiben rasgos especiales o se desarrollan sin indicios. Ese fue el caso de tres eventos cálidos en los últimos años: el fallido evento del 2014, El Niño Godzilla del 2015/16 y el intenso El Niño costero del verano de 2017 (Fig. 1). En este trabajo presentamos una descripción de estos eventos, con énfasis en El Niño costero del 2017 y su posible forzante atmosférico. |
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| First ANDEX Workshop | GEWEX News | Garreaud, R.; Poveda, G. | 2018 | Agua y Extremos | http://dgf.uchile.cl/rene/PUBS/GEWEX_News_Nov2018_red.pdf | 13-15 | Vol: 29 Issue: 4 | English | |||||
| Facing the climate change conundrum at the South Pole: actors’ perspectives on the implications of global warming for Chilean Antarctic governance | Polar Research | Gladkova, E.; Blanco-Wells, G.; Nahuelhual, L. | 2018 | Gobernanza e Interfaz Ciencia y Política | 10.1080/17518369.2018.1468195 | https://www.tandfonline.com/doi/full/10.1080/17518369.2018.1468195 | 1468195 | Vol: 37 Issue: 1 | 1751-8369 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Antarctica is recognized as being geopolitically and scientifically important, and as one of the regions with the greatest potential to affect and be affected by global climate change. Still, little is known in practice about how climate change will be handled within the main governance framework of the continent: the Antarctic Treaty System (ATS). Using qualitative interviews, participant observations and policy document analysis, this paper explores the perspectives of Chilean scientific, political and non-governmental actors regarding the implications of climate change for the current Antarctic governance framework. Results corroborate a misalignment of the climate change agenda and the ATS, stemming from the divergent views displayed by a wide network of actors. From the interviews, two predominant visions emerge: (i) climate change as an opportunity, where actors recognize the role of Antarctica in regulating global climate and stress greater opportunities to conduct Antarctic-based climate change research, the need for strategic international collaboration, and the reinforcement of Chile’s position in Antarctica through science; (ii) climate change as a burden where actors acknowledge climate change as a global problem, largely external to Antarctica, express disbelief regarding the effectiveness of local actions to tackle climate change and do not associate with climate change governance. The study concludes that climate change may become a dividing, rather than a unifying, field of action in Chilean Antarctic governance, reinforcing previously existing geopolitical tendencies. |
| The 2010-2015 Megadrought and its influence on the fire regime in central and south-central Chile | Ecosphere | González, M.; Gómez-González, S.; Lara, A.; Garreaud, R.; Díaz-Hormazábal, I. | 2018 | Agua y Extremos; Cambio de Uso de Suelo | 10.1002/ecs2.2300 | http://doi.wiley.com/10.1002/ecs2.2300 | e02300 | Vol: 9 Issue: 8 | 2150-8925 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Forest fire activity has increased in recent years in central and south-central Chile. Drought conditions have been associated with the increase of large wildfires, area burned and longer fire seasons. This study examines the influence of drought on fire regimes and discusses landscape management opportunities to decrease fire hazard. Specifically, we investigate the effect of the 2010–2015 Megadrought (MD) compared to 1990–2009 period on fire activity (fire-season length, number of fires and burned area across months, fire sizes, regions and vegetation cover types, simultaneity, and duration of fires) in central and south-central Chile (32°–39° S), using contemporary fire statistics derived from the Chilean Forest Service. For large fire events (>200 ha) the average season length increased by 67 d (44%), comparing 2010–2015 to 1990–2009. Earlier and later ignition dates resulted in extended fire seasons in MD years. During the MD, the number, area burned, simultaneity, and duration of large fires increased significantly compared to the control period, including the unprecedented occurrence of large fires during winter. The burned area in large fires increased in all vegetation types, during the MD compared to the control period, especially in the exotic plantation cover type. The regions that were most affected by fire (i.e., total area burned) during the MD wereMaule, B ıo-B ıo, and Araucan ıa (35–39° S) that concentrate >75% of forest plantations in Chile. Although both maximum temperatures and precipitation are drivers of fire activity, a simple attribution analysis indicates that the sustained rainfall deficit during 2010–2015 was the most critical factor in the enhanced fire activity. Future climate change predictions indicate more recurrent, intense, and temporally extended droughts for central and south-central Chile. Under this scenario, land-use planning and fire and forest management strategies must promote a more diverse and less flammable landscape mosaic limiting high load, homogenous, and continuous exotic plantations. |
| Active Crossfire Between Cyanobacteria and Cyanophages in Phototrophic Mat Communities Within Hot Springs | Frontiers in Microbiology | Guajardo-Leiva, S.; Pedrós-Alió, C.; Salgado, O.; Pinto, F.; Díez, B. | 2018 | Zonas Costeras | 10.3389/fmicb.2018.02039 | https://www.frontiersin.org/article/10.3389/fmicb.2018.02039/full | art: 2039 | Vol: 9 | 1664-302X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Cyanophages are viruses with a wide distribution in aquatic ecosystems, that specifically infect Cyanobacteria. These viruses can be readily isolated from marine and fresh waters environments; however, their presence in cosmopolitan thermophilic phototrophic mats remains largely unknown. This study investigates the morphological diversity (TEM), taxonomic composition (metagenomics), and active infectivity (metatranscriptomics) of viral communities over a thermal gradient in hot spring phototrophic mats from Northern Patagonia (Chile). The mats were dominated (up to 53%) by cosmopolitan thermophilic filamentous true-branching cyanobacteria from the genus Mastigocladus, the associated viral community was predominantly composed of Caudovirales (70%), with most of the active infections driven by cyanophages (up to 90% of Caudovirales transcripts). Metagenomic assembly lead to the first full genome description of a T7-like Thermophilic Cyanophage recovered from a hot spring (Porcelana Hot Spring, Chile), with a temperature of 58°C (TC-CHP58). This could potentially represent a world-wide thermophilic lineage of podoviruses that infect cyanobacteria. In the hot spring, TC-CHP58 was active over a temperature gradient from 48 to 66°C, showing a high population variability represented by 1979 single nucleotide variants (SNVs). TC-CHP58 was associated to the Mastigocladus spp. by CRISPR spacers. Marked differences in metagenomic CRISPR loci number and spacers diversity, as well as SNVs, in the TC-CHP58 proto-spacers at different temperatures, reinforce the theory of co-evolution between natural virus populations and cyanobacterial hosts. Considering the importance of cyanobacteria in hot spring biogeochemical cycles, the description of this new cyanopodovirus lineage may have global implications for the functioning of these extreme ecosystems. |
| Spatial and temporal disaggregation of the on-road vehicle emission inventory in a medium-sized Andean city. Comparison of GIS-based top-down methodologies | Atmospheric Environment | Gómez, C.; González, C.; Osses, M.; Aristizábal, B. | 2018 | Ciudades Resilientes | 10.1016/j.atmosenv.2018.01.049 | http://linkinghub.elsevier.com/retrieve/pii/S1352231018300633 | 142-155 | Vol: 179 | 1352-2310 | Thomson Reuters ISI (SCIE) | English | Emission data is an essential tool for understanding environmental problems associated with sources and dynamics of air pollutants in urban environments, especially those emitted from vehicular sources. There is a lack of knowledge about the estimation of air pollutant emissions and particularly its spatial and temporal distribution in South America, mainly in medium-sized cities with population less than one million inhabitants. This work performed the spatial and temporal disaggregation of the on-road vehicle emission inventory (EI) in the medium-sized Andean city of Manizales, Colombia, with a spatial resolution of 1 km × 1 km and a temporal resolution of 1 h. A reported top-down methodology, based on the analysis of traffic flow levels and road network distribution, was applied. Results obtained allowed the identification of several hotspots of emission at the downtown zone and the residential and commercial area of Manizales. Downtown exhibited the highest percentage contribution of emissions normalized by its total area, with values equal to 6% and 5% of total CO and PM10 emissions per km2 respectively. These indexes were higher than those obtained in residential-commercial area with values of 2%/km2 for both pollutants. Temporal distribution showed strong relationship with driving patterns at rush hours, as well as an important influence of passenger cars and motorcycles in emissions of CO both at downtown and residential-commercial areas, and the impact of public transport in PM10 emissions in the residential-commercial zone. Considering that detailed information about traffic counts and road network distribution is not always available in medium-sized cities, this work compares other simplified top-down methods for spatially assessing the on-road vehicle EI. Results suggested that simplified methods could underestimate the spatial allocation of downtown emissions, a zone dominated by high traffic of vehicles. The comparison between simplified methods based on total traffic counts and road density distribution suggested that the use of total traffic counts in a simplified form could enhance higher uncertainties in the spatial disaggregation of emissions. Results obtained could add new information that help to improve the air pollution management system in the city and contribute to local public policy decisions. Additionally, this work provides appropriate resolution emission fluxes for ongoing research in atmospheric modeling in the city, with the aim to improve the understanding of transport, transformation and impacts of pollutant emissions in urban air quality. | |
| Portugal and Chile: Longing for sustainable forestry while rising from the ashes | Environmental Science & Policy | Gómez-González, S.; Ojeda, F.; Fernandes, P. | 2018 | Cambio de Uso de Suelo | 10.1016/j.envsci.2017.11.006 | http://linkinghub.elsevier.com/retrieve/pii/S1462901117307694 | 104-107 | Vol: 81 | 1462-9011 | Thomson Reuters ISI (SCIE) | English | The recent catastrophic wildfires in Portugal and Chile shared similar features, not just because they developed under extreme weather conditions but also because extensive forest plantations were involved. Dense forest plantations of flammable pine and eucalypt species favor the development of high-intensity large fires, threatening people and the forest industry sustainability under increasingly frequent and severe drought events. Preventive land-use planning and cost-effective fuel management are key elements of sustainable forestry. Understanding the fire ecology context prior to plantation establishment is also crucial for the success of fire management planning. Although the forest industry has contributed to the economy of these countries, improved regulation and science-based management policies are strongly needed. Fuel treatment strategies can be optimized by risk-based modeling approaches, and should be mandatory in wildland-urban interfaces. The tragedy caused by these wildfires is an opportunity to change towards more sustainable landscape arrangements that reconcile ecosystem services, biodiversity conservation, and protection from life-threatening wildfires. | |
| Heat shock and plant leachates regulate seed germination of the endangered carnivorous plant <i>Drosophyllum lusitanicum</i> | Web Ecology | Gómez-González, S.; Paniw, M.; Antunes, K.; Ojeda, F. | 2018 | Cambio de Uso de Suelo | 10.5194/we-18-7-2018 | https://www.web-ecol.net/18/7/2018/ | 7-13 | Vol: 18 Issue: 1 | 1399-1183 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | In fire-prone ecosystems, many plant species have specialized mechanisms of seed dormancy that ensure a successful recruitment after fire. A well-documented mechanism is the germination stimulated by firerelated cues, such as heat shock and smoke. However, less is known about the role of inhibitory germination signals (e.g. allelopathy) in regulating post-fire recruitment. Plant leachates derived from the unburned vegetation can enforce dormancy by means of allelopathic compounds, acting as a signal of unfavourable (highly competitive) niche for germination in pyrophyte species. Here, we assessed the separate effects of heat shock and plant leachates on seed germination of Drosophyllum lusitanicum, an endangered carnivorous plant endemic to Mediterranean fire-prone heathlands. We performed a germination experiment in which seeds were subjected to three treatments: (1) 5 min at 100 °C, (2) watering with plant leachate, and (3) control. Germination rate and seed viability was determined after 63 days. Heat shock stimulated seed germination in D. lusitanicum while plant leachates had inhibitory germination effects without reducing seed viability. Thus, both positive and negative signals could be involved in its successful post-fire recruitment. Fire would break seed dormancy and stimulate seed germination of D. lusitanicum through high temperatures, but also by eliminating allelochemical compounds from the soil. These results help to understand the population dynamics patterns found for D. lusitanicum in natural populations, and highlight the role of fire in the ecology and conservation of this endangered species. Seed dormancy imposed by plant-derived leachates as an adaptive mechanism should be considered more in fire ecology theory. |
| Applying knowledge governance to understand the role of science in environmental regulation: The case of arsenic in Chile | Environmental Science & Policy | Ibarra, C.; O’Ryan, R.; Silva, B. | 2018 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.envsci.2018.05.002 | http://linkinghub.elsevier.com/retrieve/pii/S1462901118300212 | 115-124 | Vol: 86 | 1462-9011 | Thomson Reuters ISI (SCIE) | English | The relationship between scientific knowledge and decision-making surrounding environmental issues is complex and represents a flourishing area of scholarship and practice. However, a sense of frustration persists regarding efforts to increase the use of science for decision-making. Regulations of copper smelter arsenic emissions developed in Chile during the 1990s represent a successful example of science informing policy making. The case involved production and use of local science in contrast to the common practice of copying international ambient standards. In this paper, we investigate arsenic regulation in Chile in the 1990s and focus on the role of the major science intervention during the process, project FONDEF2-24. The case is examined through the lens of knowledge governance (van Kerkhoff and Pilbeam, 2017). This theoretically-oriented approach guides our critical reflection on the relationship between knowledge and policy making, taking into consideration the formal and informal rules that shape the intervention and the underlying social and cultural patterns. The success of the science intervention’s influence on policy is better understood with such a perspective. We expand the knowledge governance approach by scrutinizing the relations of coherence between levels of analysis to assess their alignment. The approach could be helpful for studying other cases, particularly at times when a new field of policy is emerging. |
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| VEIN v0.2.2: an R package for bottom–up vehicular emissions inventories | Geoscientific Model Development | Ibarra-Espinosa, S.; Ynoue, R.; O'Sullivan, S.; Pebesma, E.; Andrade, M.; Osses, M. | 2018 | Ciudades Resilientes | 10.5194/gmd-11-2209-2018 | https://www.geosci-model-dev.net/11/2209/2018/ | 2209-2229 | Vol: 11 Issue: 6 | 1991-9603 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Emission inventories are the quantification of pollutants from different sources. They provide important information not only for climate and weather studies but also for urban planning and environmental health protection. We developed an open-source model (called Vehicular Emissions Inventory – VEIN v0.2.2) that provides high-resolution vehicular emissions inventories for different fields of studies. We focused on vehicular sources at street and hourly levels due to the current lack of information about these sources, mainly in developing countries. The type of emissions covered by VEIN are exhaust (hot and cold) and evaporative considering the deterioration of the factors. VEIN also performs speciation and incorporates functions to generate and spatially allocate emissions databases. It allows users to load their own emission factors, but it also provides emission factors from the road transport model (Copert), the United States Environmental Protection Agency (EPA) and Brazilian databases. The VEIN model reads, distributes by age of use and extrapolates hourly traffic data, and it estimates emissions hourly and spatially. Based on our knowledge, VEIN is the first bottom–up vehicle emissions software that allows input to the WRF-Chem model. Therefore, the VEIN model provides an important, easy and fast way of elaborating or analyzing vehicular emissions inventories under different scenarios. The VEIN results can be used as an input for atmospheric models, health studies, air quality standardizations and decision making. |
| Spatio-temporal patterns of thermal anomalies and drought over tropical forests driven by recent extreme climatic anomalies | Philosophical Transactions of the Royal Society B: Biological Sciences | Jimenez, J.; Barichivich, J.; Mattar, C.; Takahashi, K.; Santamaría-Artigas, A.; Sobrino, J.; Malhi, Y. | 2018 | Cambio de Uso de Suelo | 10.1098/rstb.2017.0300 | http://rstb.royalsocietypublishing.org/lookup/doi/10.1098/rstb.2017.0300 | 20170300 | Vol: 373 Issue: 1760 | 0962-8436 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | The recent 2015-2016 El Niño (EN) event was considered as strong as the EN in 1997-1998. Given such magnitude, it was expected to result in extreme warming and moisture anomalies in tropical areas. Here we characterize the spatial patterns of temperature anomalies and drought over tropical forests, including tropical South America (Amazonia), Africa and Asia/Indonesia during the 2015-2016 EN event. These spatial patterns of warming and drought are compared with those observed in previous strong EN events (1982-1983 and 1997-1998) and other moderate to strong EN events (e.g. 2004-2005 and 2009-2010). The link between the spatial patterns of drought and sea surface temperature anomalies in the central and eastern Pacific is also explored. We show that indeed the EN2015-2016 led to unprecedented warming compared to the other EN events over Amazonia, Africa and Indonesia, as a consequence of the background global warming trend. Anomalous accumulated extreme drought area over Amazonia was found during EN2015-2016, but this value may be closer to extreme drought area extents in the other two EN events in 1982-1983 and 1997-1998. Over Africa, datasets disagree, and it is difficult to conclude which EN event led to the highest accumulated extreme drought area. Our results show that the highest values of accumulated drought area over Africa were obtained in 2015-2016 and 1997-1998, with a long-term drying trend not observed over the other tropical regions. Over Indonesia, all datasets suggest that EN 1982-1983 and EN 1997-1998 (or even the drought of 2005) led to a higher extreme drought area than EN2015-2016. Uncertainties in precipitation datasets hinder consistent estimates of drought severity over tropical regions, and improved reanalysis products and station records are required.This article is part of a discussion meeting issue 'The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications'. © 2018 The Author(s). |
| Indoor PM2.5 in an urban zone with heavy wood smoke pollution: The case of Temuco, Chile | Environmental Pollution | Jorquera, H.; Barraza, F.; Heyer, J.; Valdivia, G.; Schiappacasse, L.; Montoya, L. | 2018 | Ciudades Resilientes | 10.1016/j.envpol.2018.01.085 | https://www.ncbi.nlm.nih.gov/pubmed/29414372 | 477-487 | Vol: 236 | 0269-7491 | Thomson Reuters ISI (SCIE) | English | Temuco is a mid-size city representative of severe wood smoke pollution in southern Chile; however, little is known about the indoor air quality in this region. A field measurement campaign at 63 households in the Temuco urban area was conducted in winter 2014 and is reported here. In this study, indoor and outdoor (24-hr) PM2.5 and its elemental composition were measured and compared. Infiltration parameters and outdoor/indoor contributions to indoor PM2.5 were also determined. A statistical evaluation of how various air quality interventions and household features influence indoor PM2.5 was also performed. This study determined median indoor and outdoor PM2.5 concentrations of 44.4 and 41.8 μg/m3, respectively. An average infiltration factor (0.62 ± 0.06) was estimated using sulfur as a tracer species. Using a simple mass balance approach, median indoor and outdoor contributions to indoor PM2.5 concentrations were then estimated as 12.5 and 26.5 μg/m3, respectively; therefore, 68% of indoor PM2.5 comes from outdoor infiltration. This high percentage is due to high outdoor pollution and relatively high household air exchange rates (median: 1.06 h−1). This study found that S, Br and Rb were dominated by outdoor contributions, while Si, Ca, Ti, Fe and As originated from indoor sources. Using continuous indoor and outdoor PM2.5 measurements, a median indoor source strength of 75 μg PM2.5/min was estimated for the diurnal period, similar to literature results. For the evening period, the median estimate rose to 135 μg PM2.5/min, reflecting a more intense wood burning associated to cooking and space heating at night. Statistical test results (at the 90% confidence level) support the ongoing woodstove replacement program (reducing emissions) and household weatherization subsidies (reducing heating demand) for improving indoor air quality in southern Chile, and suggest that a cookstove improvement program might be helpful as well. In the city of Temuco, southern Chile, 68% of indoor PM2.5 comes from severe outdoor pollution due to intensive wood burning, enhanced by poor household building standards and fuel poverty. | |
| Ambient PM10 impacts brought by the extreme flooding event of March 24–26, 2015, in Copiapó, Chile | Air Quality, Atmosphere & Health | Jorquera, H.; Villalobos, A.; Barraza, F. | 2018 | Ciudades Resilientes | 10.1007/s11869-018-0549-5 | http://link.springer.com/10.1007/s11869-018-0549-5 | 341–351 | Vol: 11 | 1873-9318 | Thomson Reuters ISI (SCIE) | English | On March 24–26, 2015, the Chilean city of Copiapó (27° 22′ S, 70° 20′ W), located in the hyperarid Atacama Desert, suffered an intense flooding brought by an extreme, unique rainfall event with a 35-year record of daily precipitation. A receptor model (positive matrix factorization, version 5) analysis, applied to ambient PM10 chemical speciation from three short-term sampling campaigns, resolved four sources: crustal/road dust, sea salt, secondary sulfates, and emissions from Paipote copper smelter located 8 km east of Copiapó. Wind trajectories computed with US NOAA’s Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT) supported the above source identification and explained variability in source contributions. It was found that crustal/road dust increased 50 μg/m3, in April 8–10, 2015, as compared with values in November 2014 and October–November 2015, respectively. This was the dominant PM10 source after the flooding and before debris were cleaned up, being on order of magnitude higher that the other source contributions. The Paipote copper smelter contributed with primary PM10 emissions and secondary sulfates; this combined contribution averaged 11.8 μg/m3. Sea salt contributions contributed an average of 3.3 μg/m3. In normal conditions, crustal/road dust averaged 2.9 μg/m3, but the other resolved sources also contributed with crustal elements as their emissions are transported by winds to Copiapó. The positive matrix factorization solution included an unresolved concentration of 7.4 μg/m3. The small number of samples and the lack of measurements of nitrate, ammonia, and organic and elemental carbon may explain this result. Hence, sources such as secondary nitrates and combustion sources plus fugitive dust from sources surrounding Copiapó might be included in that unresolved concentration. | |
| The PMIP4 contribution to CMIP6 – Part 1: Overview and over-arching analysis plan | Geoscientific Model Development | Kageyama, M.; Braconnot, P.; Harrison, S.; Haywood, A.; Jungclaus, J.; Otto-Bliesner, B.; Peterschmitt, J.; Abe-Ouchi, A.; Albani, S.; Bartlein, P.; Brierley, C.; Crucifix, M.; Dolan, A.; Fernandez-Donado, L.; Fischer, H.; Hopcroft, P.; Ivanovic, R.; Lambert, F.; Lunt, D.; Mahowald, N.; Peltier, W.;... | 2018 | Ciudades Resilientes | 10.5194/gmd-11-1033-2018 | https://www.geosci-model-dev.net/11/1033/2018/ | 1033-1057 | Vol: 11 Issue: 3 | 1991-9603 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | This paper is the first of a series of four GMD papers on the PMIP4-CMIP6 experiments. Part 2 (Otto-Bliesner et al., 2017) gives details about the two PMIP4-CMIP6 interglacial experiments, Part 3 (Jungclaus et al., 2017) about the last millennium experiment, and Part 4 (Kageyama et al., 2017) about the Last Glacial Maximum experiment. The mid-Pliocene Warm Period experiment is part of the Pliocene Model Intercomparison Project (PlioMIP) – Phase 2, detailed in Haywood et al. (2016). The goal of the Paleoclimate Modelling Intercomparison Project (PMIP) is to understand the response of the climate system to different climate forcings for documented climatic states very different from the present and historical climates. Through comparison with observations of the environmental impact of these climate changes, or with climate reconstructions based on physical, chemical, or biological records, PMIP also addresses the issue of how well state-of-the-art numerical models simulate climate change. Climate models are usually developed using the present and historical climates as references, but climate projections show that future climates will lie well outside these conditions. Palaeoclimates very different from these reference states therefore provide stringent tests for state-of-the-art models and a way to assess whether their sensitivity to forcings is compatible with palaeoclimatic evidence. Simulations of five different periods have been designed to address the objectives of the sixth phase of the Coupled Model Intercomparison Project (CMIP6): the millennium prior to the industrial epoch (CMIP6 name: past1000); the mid-Holocene, 6000 years ago (midHolocene); the Last Glacial Maximum, 21 000 years ago (lgm); the Last Interglacial, 127 000 years ago (lig127k); and the mid-Pliocene Warm Period, 3.2 million years ago (midPliocene-eoi400). These climatic periods are well documented by palaeoclimatic and palaeoenvironmental records, with climate and environmental changes relevant for the study and projection of future climate changes. This paper describes the motivation for the choice of these periods and the design of the numerical experiments and database requests, with a focus on their novel features compared to the experiments performed in previous phases of PMIP and CMIP. It also outlines the analysis plan that takes advantage of the comparisons of the results across periods and across CMIP6 in collaboration with other MIPs. |
| Towards an environmental education for a complex society. an analysis from the social systems theory; [Hacia una educación ambiental para una sociedad compleja. Un análisis desde la teoría de sistemas sociales] | Revista Mad | Labraña, J.; Amigo, C.; Cortés, J.; Gómez, E.; Moreno, J.; Muñoz, M. | 2018 | Ciudades Resilientes | 10.5354/0719-0527.2018.53283 | https://revistamad.uchile.cl/index.php/RMAD/article/view/53283/55965 | 13-45 | Vol: - Issue: 39 | 0718-0527 | Thomson Reuters ISI (ESCI) | Spanish | As a result of the multiple ecological problems affecting contemporary society, environmental education has become increasingly important in recent decades. However, despite its importance, this concern does not seem to have gone hand in hand with the consideration of environmental education within the framework of a complex enought sociological theory. As we will argue in this article, this has had important effects in the conceptualization of environmental education, which is hence generally described as a process of ethical socialization with the aim of improving society. Using the distinctions of Luhmann's social systems theory of social systems between a) psychic and social systems and b) different functional systems, we will propose an understanding of environmental education as an intentional effort to socialize about the relationship between society and its physical environment, which, as part of the communications of a specialized system, reflect society's form of differentiation. Once this definition is proposed, we will propose a model of environmental education for a functionally differentiated society, taking Chile as example. The article closes with a summary, future lines of research and policy recommendations. © 2018 Universidad de Chile. All rights reserved. | |
| Hydroclimatic conditions trigger record harmful algal bloom in western Patagonia (summer 2016) | Scientific Reports | León-Muñoz, J.; Urbina, M.; Garreaud, R.; Iriarte, J. | 2018 | Agua y Extremos | 10.1038/s41598-018-19461-4 | http://www.nature.com/articles/s41598-018-19461-4 | art: 1330 | Vol: 8 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | A harmful algal bloom (HAB) of the raphidophyta alga Pseudochattonella cf. verruculosa during the 2016 austral summer (February-March) killed nearly 12% of the Chilean salmon production, causing the worst mass mortality of fish and shellfish ever recorded in the coastal waters of western Patagonia. The HAB coincided with a strong El Ninõ event and the positive phase of the Southern Annular Mode that altered the atmospheric circulation in southern South America and the adjacent Pacific Ocean. This led to very dry conditions and higher than normal solar radiation reaching the surface. Using time series of atmospheric, hydrologic and oceanographic data we show here that an increase in surface water temperature and reduced freshwater input resulted in a weakening of the vertical stratification in the fjords and sounds of this region. This allowed the advection of more saline and nutrient-rich waters, ultimately resulting in an active harmful algal bloom in coastal southern Chile. |
| Effect of climate on tree growth in the Pampa biome of Southeastern South America: First tree-ring chronologies from Uruguay | Dendrochronologia | Lucas, C.; Puchi, P.; Profumo, L.; Ferreira, A.; Muñoz, A. | 2018 | Agua y Extremos | 10.1016/j.dendro.2018.10.004 | https://linkinghub.elsevier.com/retrieve/pii/S1125786518300249 | 113-122 | Vol: 52 | 1125-7865 | Thomson Reuters ISI (SCIE) | English | Tree-ring research in the highland tropics and subtropics represents a major frontier for understanding climate-growth relationships. Nonetheless, there are many lowland regions – including the South American Pampa biome – with scarce tree ring data. We present the first two tree-ring chronologies for Scutia buxifolia in subtropical Southeastern South America (SESA), using 54 series from 29 trees in two sites in northern and southern Uruguay. We cross-dated annual rings and compared tree growth from 1950 to 2012 with regional climate variability, including rainfall, temperature and the Palmer Drought Severity Index – PDSI, the El Niño Southern Oscillation (ENSO) and the Southern Annular Mode (SAM). Overall, ring width variability was highly responsive to climate signals linked to water availability. For example, tree growth was positively correlated with accumulated rainfall in the summer-fall prior to ring formation for both chronologies. Summer climate conditions were key for tree growth, as shown by a negative effect of hot summer temperatures and a positive correlation with PDSI in late austral summer. The El Niño phase in late spring/early summer favored an increase in rainfall and annual tree growth, while the La Niña phase was associated with less rainfall and reduced tree growth. Extratropical climate factors such as SAM had an equally relevant effect on tree growth, whereby the positive phase of SAM had a negative effect over radial growth. These findings demonstrate the potential for dendroclimatic research and climate reconstruction in a region with scarce tree-ring data. They also improve the understanding of how climate variability may affect woody growth in native forests – an extremely limited ecosystem in the Pampa biome. | |
| Controversies in social-ecological systems: Lessons from a major red tide crisis on Chiloe island, Chile | Ecology and Society | Mascareño, A.; Cordero, R.; Azócar, G.; Billi, M.; Henríquez, P.; Ruz, G. | 2018 | Gobernanza e Interfaz Ciencia y Política | 10.5751/ES-10300-230415 | https://doi.org/10.5751/ES-10300-230415 | art: 15 | Vol: 23 Issue: 4 | 1708-3087 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Connecting the discussions on resilience and governance of social-ecological systems (SESs) with the sociological analysis of social controversies, we explore a major red tide crisis on Chiloe Island, southern Chile, in 2016. Theoretically, we argue that controversies not only are methodological devices for the observation of the complex relations between nature and society in moments of crisis, but also are materially embedded in the SES dynamics and can work for or against systemic resilience. Empirically, we show that Chiloe’s SES is an unstable regime prone to sudden shifts and identify the configuration of different lock-in mechanisms expressed in the reproduction of structural fragilities over the last three decades. From the examination of the social controversies on the 2016 red tide crisis, we draw several lessons. First, there is a complex interplay of visible and hidden fragilities of Chiloe’s SES that, while being ignored or their resolution postponed to the future, materialize in the daily experience of inhabitants as a series of historical disappointments. Second, the unfolding of Chiloe’s social-ecological crises involves epistemic disputes not only over concrete events but also on the very construction of the SES as a social-natural reality. In turn, this creates conditions for the emergence of strategic alignments between local, national, and transnational actors and shows the extent to which the socio-political articulation of knowledge may contribute to either improve or block the governance of the SES. Third, the social resources that came to light with the controversies reveal pathways for improving the governance regime of Chiloe Island’s SES. This dimension highlights the normative relevance of commitments to recognize multiple scales of knowledge and articulate a plurality of actors in a nonhierarchical logic of cooperation. © 2018 by the author(s). |
| The influence of river discharge on nutrient export and phytoplankton biomass off the Central Chile coast (33º-37ºS). Seasonal cycle and interannual variability | Frontier in Marine Science | Masotti, I.; Aparicio-Rizzo, P.; Yevenes, M.; Garreaud, R.; Farías, L. | 2018 | Zonas Costeras | 10.3389/fmars.2018.00423 | https://doi.org/10.3389/fmars.2018.00423 | 423 | Vol: 5 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Using in situ hydro-chemical data and MODIS-SeaWiFS ocean color images as a proxy of river plumes and phytoplankton biomass from 2000 to 2014, this study documents the temporal co-variability of river discharge, plume area, nitrate and phosphate export and phytoplankton biomass in the coastal waters off Central Chile (33º-37ºS). Five major rivers (Maipo, Mataquito, Maule, Itata and Biobío) drain into this region with annual mean discharge ranging from 120 to 1000 m3 s-1. River discharge and coastal plume area present a marked seasonal cycle, reaching maximum values during the winter rainy season (June-September). Export of riverine nutrients also peaks in winter, leading to an increase in phytoplankton biomass within the plumes that can be twice larger than the background values in coastal areas away from the river mouths. Wintertime river discharge, plume area and nutrient export are also correlated at interannual time scales. During a recent extended dry period (2010-2014), river discharges, plume areas and nutrient export clearly decreased by about 50% compared to historical values, reducing significantly the size of the chlorophyll pool within plumes off Central Chile during winter. The potential impacts of droughts are discussed in terms of coastal ecology and primary production, a highly relevant issue considering the projections of a dry climate over Central Chile in the future. Systematic evidence of mega-drought effects upon coastal productivity still does not exist, but it remains a priority to further investigate and quantify these impacts. |
| Impact of residential combustion and transport emissions on air pollution in Santiago during winter | Atmospheric Environment | Mazzeo, A.; Huneeus, N.; Ordoñez, C.; Orfanoz-Cheuquelaf, A.; Menut, L.; Mailler, S.; Valari, M.; Denier van der Gon, H.; Gallardo, L.; Muñoz, R.; Donoso, R.; Galleguillos, M.; Osses, M.; Tolvett, S. | 2018 | Cambio de Uso de Suelo; Ciudades Resilientes | 10.1016/j.atmosenv.2018.06.043 | https://linkinghub.elsevier.com/retrieve/pii/S1352231018304345 | 195-208 | Vol: 190 | 1352-2310 | Thomson Reuters ISI (SCIE) | English | Santiago (33.5°S, 70.5°W), the capital of Chile, is frequently affected by extreme air pollution events during wintertime deteriorating air quality (AQ) and thus affecting the health of its population. Intense residential heating and on-road transport emissions combined with poor circulation and vertical mixing are the main factors responsible for these events. A modelling system composed of a chemistry-transport model (CHIMERE) and a meteorological model (WRF) was implemented to assess the AQ impacts of residential and transportation sources in the Santiago basin. A two-week period of July 2015 with various days with poor AQ was simulated focusing on the impact on AQ with respect to fully inhalable particles (PM2.5) and nitrogen oxides (NOX). Three emission scenarios, within the range of targeted reductions of the decontamination plan of Santiago, were tested; namely 50% reduction of residential emission, 50% reduction of transport emissions and the combination of both. An additional scenario decreasing transport emissions in 10% was carried out to examine whether a linear dependence of surface concentrations on changes in emissions exists. The system was validated against surface and vertically resolved meteorological measurements. The model reproduces the daily surface concentration variability from the AQ monitoring network of Santiago. However, the model not fully captures the emissions variations inferred from the observations which may be due to missing sources such as resuspension of dust. Results show that, during the period studied, although both residential and transportation sources contribute to observed AQ levels in Santiago, reducing transport emissions is more effective in terms of reducing the number of days with pollution events than decreasing residential combustion. This difference in impact is largely due to the spatial distribution of the emission sources. While most of the residential combustion is emitted in the outskirts of the city, most of the transport emissions occur within the city, where most of the stations from AQ monitoring network of Santiago are located. As can be expected, the largest improvement of AQ in Santiago is achieved by the combined reduction of emissions in both sectors. Sensitivity analysis with 10% reduction in transport emissions reveals a linear behavior between emissions and concentrations for NOX and approximate linear behavior for PM2.5. The absence of secondary aerosols formation and dust resuspension in the current simulation could explain this deviation from linearity for fine particles. Nevertheless, it suggests that the results can be used for mitigation policies with emissions reductions below the 50% used in this study. |
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| Landscape drivers of recent fire activity (2001-2017) in south-central Chile | PLOS ONE | McWethy, D.; Pauchard, A.; García, R.; Holz, A.; González, M.; Veblen, T.; Stahl, J.; Currey, B. | 2018 | Cambio de Uso de Suelo | 10.1371/journal.pone.0201195 | http://dx.plos.org/10.1371/journal.pone.0201195 | e0201195 | Vol: 13 Issue: 8 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In recent decades large fires have affected communities throughout central and southern Chile with great social and ecological consequences. Despite this high fire activity, the controls and drivers and the spatiotemporal pattern of fires are not well understood. To identify the large-scale trends and drivers of recent fire activity across six regions in south-central Chile (~32–40 S Latitude) we evaluated MODIS satellite-derived fire detections and compared this data with Chilean Forest Service records for the period 2001–2017. MODIS burned area estimates provide a spatially and temporally comprehensive record of fire activity across an important bioclimatic transition zone between dry Mediterranean shrublands/ sclerophyllous forests and wetter deciduous-broadleaf evergreen forests. Results suggest fire activity was highly variable in any given year, with no statistically significant trend in the number of fires or mean annual area burned. Evaluation of the variables associated with spatiotemporal patterns of fire for the 2001–2017 period indicate vegetation type, biophysical conditions (e.g., elevation, slope), mean annual and seasonal climatic conditions (e.g., precipitation) and mean population density have the greatest influence on the probability of fire occurrence and burned area for any given year. Both the number of fires and annual area burned were greatest in warmer, biomass-rich lowland Bío-Bío and Araucanía regions. Resource selection analyses indicate fire ‘preferentially’ occurs in exotic plantation forests, mixed native-exotic forests, native sclerophyll forests, pasture lands and matorral, vegetation types that all provide abundant, flammable and connected biomass for burning. Structurally and compositionally homogenous exotic plantation forests may promote fire spread greater than native deciduous-Nothofagaceae forests which were once widespread in the southern parts of the study area. In the future, the coincidence of warmer and drier conditions in landscapes dominated by flammable and fuel-rich forest plantations and mixed native-exotic and sclerophyll forests are likely to further promote large fires in south-central Chile. © 2018 McWethy et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
| Monitoring Chilean native forest area: a pending challenge | Bosque (Valdivia) | Miranda, A.; Lara, A.; Altamirano, A.; Zamorano-Elgueta, C.; Hernández, H.; González, M.; Pauchard, A.; Promis, Á. | 2018 | Cambio de Uso de Suelo | 10.4067/S0717-92002018000200265 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-92002018000200265&lng=en&nrm=iso&tlng=en | 265-275 | Vol: 39 Issue: 2 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Forest monitoring is important for decision making of forest management and conservation. In Chile, the forest monitoring system was initiated in 1994, which has been continued through the implementation of regional updates. This has enabled a temporal monitoring of the distribution and surface covered by native forest. However, while regional updates have reported increase in the surface covered by native forest, other studies have shown an opposite trend. Therefore, the capacity of the forest monitoring system to measure the temporal variation in forest areas was evaluated. Specifically, a review of reports and official data of the national forest monitoring system was carried out through the fulfillment of three basic criteria: i) comparability, ii) replicability and iii) quality. According to our results, the Chilean forest monitoring system does not fulfill their basic requirements because: (i) methodologies have not been consistent over time; (ii) it does not provide a baseline of land cover or forest loss that allows comparisons with changing forest area; iii) there is not adequate error estimation and how it can affect the results and analysis of monitoring. The national forest monitoring system requires a redefinition of its aims and methods, guiding them to the long term by convening different stakeholders looking for a national agreement. |
| Co-construcción en proyectos de generación distribuida con energía solar: participación de la comunidad en el proyecto Ayllu Solar | Revista Estudios Avanzados | Montedonico, M.; Herrera-Neira, F.; Marconi, A.; Urquiza, A. | 2018 | Ciudades Resilientes | https://www.revistas.usach.cl/ojs/index.php/ideas/article/view/3397 | 4-22 | 0718-5014 | Spanish | The level of participation of communities in distributed generation projects is a fundamental challenge for energy transition processes. Based on the experience of the Ayllu Solar project in the implementation of the co-construction methodology, this article debate on the participation of the communities in the development of energy projects, identifying learning and challenges. In this context, it is emphasized that for the success of the participatory processes it is necessary to have a thorough diagnosis of the territory; develop a proposal with sociocultural relevance; establish clear rules for the operation of work teams; work with organizations previously constituted, among others key aspects. In turn, it was possible to identify four types of barriers for the implementation of the Methodology in the territory: temporal, territorial, educational and sociocultural. Finally. two critical aspects were identified for the development of projects of this type: the tension caused by the existence of several understandings in the multidisciplinary teams on the scope of local participation, on the other hand, the contradictions and difficulties marked by the distrust generated by projects that are promoted local development, but based on the development of extractive industry. Both aspects pose great challenges for the participation and sustainability of this type of projects. | ||||
| Co-construction of energy solutions: Lessons learned from experiences in Chile | Energy Research & Social Science | Montedonico, M.; Herrera-Neira, F.; Marconi, A.; Urquiza, A.; Palma-Behnke, R. | 2018 | Ciudades Resilientes | 10.1016/j.erss.2018.08.004 | https://linkinghub.elsevier.com/retrieve/pii/S2214629618308351 | 173-183 | Vol: 45 | 2214-6296 | Thomson Reuters ISI (SSCI) | English | The Energy Center has developed a co-construction methodology to address the challenges of technology transfer-based on distributed generation projects- in the context of energy transitions in isolated locations. Based on the experiences developed between 2010 and 2017, this paper analyses the process of preparing the Co-construction methodology. New tools were identified under the light of a theoretical-methodological reflection and a new version of co-construction methodology is proposed from this discussion. This learning process combines academic research and applied projects. It has provided Energy Center with an improved set of tools for current projects, and also contributed to a theoretical-methodological discussion based on new research activities. The main problems of method faced are presented during interdisciplinary work, such as: common understanding of fundamental concepts (sustainability, participation, community); the domination of one discipline over the others; the different visions of the priorities within the same project. And those problems given by the participation process under the paradox of “framing-overflowing”, where the constraints of actual projects (deadlines, budget, and specific KPIs) could limit the possibility of performing in depth diagnostics and building trust. One of the main challenges identified is that an actual impact on the overall experience is only feasible if lessons can be translated into concrete products (best practices, guidelines, tools), so can be adopted by future project developers. | |
| Comentario Sentencia del Tribunal Administrativo de Boyacá de 9 de agosto de 2018, sobre Páramo de Pisba | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2018 | Gobernanza e Interfaz Ciencia y Política | http://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-colombia-mineria-derechos-fundamentales-participacion-ciudadana/ | 1989-5666 | ESCI | ||||||
| Sentencia Tribunal Constitucional, Proyecto de Ley que “Prohíbe la entrega de bolsas plásticas de comercio en todo el territorio nacional”, 10 de julio de 2018 | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2018 | Gobernanza e Interfaz Ciencia y Política | http://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-prohibicion-de-comercio-bolsas-de-plastico/ | 1989-5666 | ESCI | ||||||
| Sentencia Corte Suprema, de 31 de agosto de 2017 | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2018 | Gobernanza e Interfaz Ciencia y Política | http://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-alud-aluvion-indemnizacion/ | 1989-5666 | ESCI | ||||||
| Sentencia del Tribunal Ambiental de Santiago, de 5 de enero de 2018 | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2018 | Gobernanza e Interfaz Ciencia y Política | http://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-participacion-ciudadana-acceso-a-la-justicia/ | 1989-5666 | ESCI | ||||||
| Comentario Sentencia Corte Suprema de Colombia, de 5 de abril de 2018 | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2018 | Gobernanza e Interfaz Ciencia y Política | http://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-colombia-deforestacion-accion-de-jovenes-y-ninos-colombianos/ | 1989-5666 | ESCI | ||||||
| Comentario a la Sentencia de la Corte Suprema, de 29 de diciembre de 2017 | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2018 | Gobernanza e Interfaz Ciencia y Política | http://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-participacion-ciudadana-consulta-indigena/ | 1989-5666 | ESCI | ||||||
| Comentario Sentencia Corte Suprema, 22 de mayo de 2018 | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2018 | Gobernanza e Interfaz Ciencia y Política | 1989-5666 | ||||||||
| Ley Marco sobre Cambio Climático (Perú) | Actualidad Jurídica Ambiental | Moraga Sariego, P. | 2018 | Gobernanza e Interfaz Ciencia y Política | 1989-5666 | ||||||||
| Informe final Océano y NDC | Moraga Sariego, P.; Farías, L.; Delgado, V.; Urquiza, A.; Morales, B. | 2018 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://www.cr2.cl/wp-content/uploads/2018/07/informe_oceano_NDC.pdf | El Acuerdo de París sobre Cambio Climático establece como obligación para los países firmantes presentar una Contribución Nacionalmente Determinada (Nationally Determined Contributions, o NDCs) y revisarla cada cinco años. Es por esta razón que la NDC de Chile está siendo sometida a un proceso de revisión con el propósito de identificar oportunidades de actualización y refinamiento de su primera versión. El Ministerio de Relaciones Exteriores, responsable de llevar a cabo esta actualización, se ha propuesto incorporar la protección y conservación del océano en dicho proceso, en conformidad con los objetivos planteados en la declaración “Because the Ocean”, así como en el “Ocean Pathway Platform” lanzado por la Presidencia de la COP23. Para ello se estableció un marco de colaboración técnica entre el Ministerio de Relaciones Exteriores, el Centro de Ciencia del Clima y la Resiliencia (CR)2 y el Centro de Derecho Ambiental (CDA) de la Facultad de Derecho de la Universidad de Chile, entre los meses de diciembre de 2017 y abril de 2018, con el objeto de generar un informe sobre la incorporación del océano en la NDC de Chile, a la luz de la agenda oceánica y en concordancia con los Objetivos de Desarrollo Sustentable (ODS). | ||||||||
| Comentario Sentencia Corte Suprema, 6 de septiembre de 2018 | Actualidad Jurídica Ambiental | Moraga Sariego, P.; Ortiz, M. | 2018 | Gobernanza e Interfaz Ciencia y Política | http://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-decreto-de-escasez-hidrica/ | 1989-5666 | ESCI | ||||||
| Sentencia Corte Suprema de 27 de agosto de 2018: Protección de Humedales Artificiales | Actualidad Jurídica Ambiental | Moraga, P.; Delgado, V. | 2018 | Gobernanza e Interfaz Ciencia y Política | http://www.actualidadjuridicaambiental.com/jurisprudencia-al-dia-iberoamerica-chile-humedales-artificiales/ | 1989-5666 | Thomson Reuters ISI (ESCI) | Spanish | |||||
| Onset and Evolution of Southern Annular Mode-Like Changes at Centennial Timescale | Scientific Reports | Moreno, P.; Vilanova, I.; Villa-Martínez, R.; Dunbar, R.; Mucciarone, D.; Kaplan, M.; Garreaud, R.; Rojas, M.; Moy, C.; De Pol-Holz, R.; Lambert, F. | 2018 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.1038/s41598-018-21836-6 | http://www.nature.com/articles/s41598-018-21836-6 | art: 3458 | Vol: 8 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Southern Westerly Winds (SWW) are the surface expression of geostrophic winds that encircle the southern mid-latitudes. In conjunction with the Southern Ocean, they establish a coupled system that not only controls climate in the southern third of the world, but is also closely connected to the position of the Intertropical Convergence Zone and CO2 degassing from the deep ocean. Paradoxically, little is known about their behavior since the last ice age and relationships with mid-latitude glacier history and tropical climate variability. Here we present a lake sediment record from Chilean Patagonia (51°S) that reveals fluctuations of the low-level SWW at mid-latitudes, including strong westerlies during the Antarctic Cold Reversal, anomalously low intensity during the early Holocene, which was unfavorable for glacier growth, and strong SWW since ∼7.5 ka. We detect nine positive Southern Annular Mode-like events at centennial timescale since ∼5.8 ka that alternate with cold/wet intervals favorable for glacier expansions (Neoglaciations) in southern Patagonia. The correspondence of key features of mid-latitude atmospheric circulation with shifts in tropical climate since ∼10 ka suggests that coherent climatic shifts in these regions have driven climate change in vast sectors of the Southern Hemisphere at centennial and millennial timescales. |
| Modulation of Fire Regimes by Vegetation and Site Type in Southwestern Patagonia Since 13 ka | Frontiers in Ecology and Evolution | Moreno, P.; Vilanova, I.; Villa-Martínez, R.; Francois, J. | 2018 | Agua y Extremos | 10.3389/fevo.2018.00034 | http://journal.frontiersin.org/article/10.3389/fevo.2018.00034/full | art: 34 | Vol: 6 | 2296-701X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | The degree to which vegetation and site type have influenced fire regimes through the Holocene has not been investigated in detail in the temperate ecosystems of southern Patagonia. Here we present a first attempt using a paired-basin approach to study the evolution of fire regimes in sectors dominated by humid Nothofagus forests and the xeric Patagonian steppe in the Magallanes region of Chilean Patagonia (51°S). We analyzed sediment cores from two small lakes and a bog located within the same climate zone on opposite sides of the forest-steppe ecotone, ~28 km apart. The position of this biological boundary east of the Andes is controlled by the strength and position of the southern westerly winds, which constitute the sole source of precipitation throughout western Patagonia. Our results indicate that fires have occurred in the study region repeated times over the last ~13,000 years at bi- and tridecadal timescales. Sectors currently dominated by Patagonian steppe feature high frequency and low magnitude of local fires, and vice versa in humid forests. Climate-driven expansion of Nothofagus scrubland/woodland into steppe environments over the last ~4,200 years increased the magnitude and lowered the frequency of fire events, culminating with peak Nothofagus abundance, fire magnitude and frequency during the last millennium. We also detect divergences between lake-based vs. bog-based paleofire histories among paired sites located within the Patagonian steppe, ~12 km apart, which we attribute to local burning of the bog at times of lowered water table. This divergence suggests to us that bog-based vegetation and fire histories exacerbate a local, azonal, signal blurring extra-local or regional regimes, thus accounting for some discrepancies in the Quaternary paleovegetation/paleoclimate literature of southern Patagonia. |
| Do people prefer natural landscapes? An empirical study in Chile; [¿La gente prefiere paisajes naturales? Un estudio empírico en Chil] | Bosque | Nahuelhual, L.; Laterra, P.; Jiménez, D.; Báez, A.; Echeverría, C.; Fuentes, R. | 2018 | Dimensión Humana | 10.4067/S0717-92002018000200205 | https://doi.org/10.4067/S0717-92002018000200205 | 205-216 | Vol: 39 Issue: 2 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | There is a growing consciousness that the viability of landscape-related policy depends on support from the general public. However, during planning stages, knowledge regarding landscape perceptions and preferences of people is generally absent or limited. This study presents an observer-based landscape assessment, applying a physical landscape attribute approach to measure visual preferences based on photographs. Data on age, gender, place of residence, income and education level were collected by means of a country-wide online questionnaire (n° answers=643), along with information from respondents on visual evaluations of images depicting various compositions and levels of scenic beauty of rural landscapes of south-central Chile. The effects of landscape composition and scenic beauty on responses (individual ratings), as well as the interaction effects between those attributes and personal characteristics, were tested by applying multivariate repeated measures ANOVA and Wilks multivariate tests. Ratings for both scenic beauty and landscape composition significantly varied across photographs, revealing a clear preference for landscapes dominated by native vegetation over landscapes dominated by exotic tree plantations or cultivated lands. A relatively low, nonetheless significant, portion of the rating variability was explained by subtle differences in preferences arising from personal characteristics. Results contribute to several recent efforts to understand public opinion regarding natural and rural landscape changes. Specifically, results sustain the adverse effects of loss of natural habitats on people’s appraisals of rural landscapes. © 2018, Universidad Austral de Chile. All rights reserved. |
| Past and future global transformation of terrestrial ecosystems under climate change | Science | Nolan, C.; Overpeck, J.; Allen, J.; Anderson, P.; Betancourt, J.; Binney, H.; Brewer, S.; Bush, M.; Chase, B.; Cheddadi, R.; Djamali, M.; Dodson, J.; Edwards, M.; Gosling, W.; Haberle, S.; Hotchkiss, S.; Huntley, B.; Ivory, S.; Kershaw, A.; Kim, S.; Latorre, C.; Leydet, M.; Lézine, A.; Liu, K.; Liu,... | 2018 | Agua y Extremos | 10.1126/science.aan5360 | http://www.sciencemag.org/lookup/doi/10.1126/science.aan5360 | 920-923 | Vol: 361 Issue: 6405 | 0036-8075 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Impacts of global climate change on terrestrial ecosystems are imperfectly constrained by ecosystem models and direct observations. Pervasive ecosystem transformations occurred in response to warming and associated climatic changes during the last glacial-to-interglacial transition, which was comparable in magnitude to warming projected for the next century under high-emission scenarios. We reviewed 594 published paleoecological records to examine compositional and structural changes in terrestrial vegetation since the last glacial period and to project the magnitudes of ecosystem transformations under alternative future emission scenarios. Our results indicate that terrestrial ecosystems are highly sensitive to temperature change and suggest that, without major reductions in greenhouse gas emissions to the atmosphere, terrestrial ecosystems worldwide are at risk of major transformation, with accompanying disruption of ecosystem services and impacts on biodiversity. |
| Atmospheric dynamics and habitability range in Earth-like aquaplanets obliquity simulations | Icarus | Nowajewski, P.; Rojas, M.; Rojo, P.; Kimeswenger, S. | 2018 | Gobernanza e Interfaz Ciencia y Política | 10.1016/j.icarus.2018.01.002 | http://linkinghub.elsevier.com/retrieve/pii/S0019103517305407 | 84-90 | Vol: 305 | 0019-1035 | Thomson Reuters ISI (SCIE) | English | We present the evolution of the atmospheric variables that affect planetary climate by increasing the obliquity by using a general circulation model (PlaSim) coupled to a slab ocean with mixed layer flux correction. We increase the obliquity between 30° and 90° in 16 aquaplanets with liquid sea surface and perform the simulation allowing the sea ice cover formation to be a consequence of its atmospheric dynamics. Insolation is maintained constant in each experiment, but changing the obliquity affects the radiation budget and the large scale circulation. Earth-like atmospheric dynamics is observed for planets with obliquity under 54°. Above this value, the latitudinal temperature gradient is reversed giving place to a new regime of jet streams, affecting the shape of Hadley and Ferrel cells and changing the position of the InterTropical Convergence Zone. As humidity and high temperatures determine Earth’s habitability, we introduce the wet bulb temperature as an atmospheric index of habitability for Earth-like aquaplanets with above freezing temperatures. The aquaplanets are habitable all year round at all latitudes for values under 54°; above this value habitability decreases toward the poles due to high temperatures. |
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| Vulnerabilidad de las Mujeres Indígenas del norte de Chile frente al Cambio Climático | ONU Mujeres | 2018 | Ciudades Resilientes | https://www.cr2.cl/wp-content/uploads/2021/01/ONU-Mujeres-Vulnerabilidad-mujeres-indigenas-norte-Chile-CC.pdf | English | Este documento, elaborado en el marco del Programa “Originarias: Empoderamiento de Mujeres Indígenas del Norte de Chile para el Desarrollo Sostenible” de ONU Mujeres Chile y apoyado por Teck Resources, presenta un análisis con enfoque de género de las percepciones de riesgo y vulnerabilidad ante el cambio climático de las mujeres indígenas de la macrozona del norte de Chile, específicamente de las regiones de Tarapacá, Antofagasta y Atacama, incorporando en este análisis las condiciones actuales y poyecciones futuras del clima en esta macrozona. La Convención Marco de Naciones Unidades para el Cambio Climático en su 22a Conferencia de las Partes, reiteró su compromiso de incorporar el enfoque de género en la acción climática y los mecanismos de financiamiento, debido por una parte, a que las desigualdades de género existentes probablemente se verán exacerbadas por el cambio climático y por otra, a que la capacidad de agencia, el conocimiento y el liderazgo de las mujeres en la acción climática para la mitigación, la adaptación, el manejo de desastres y su capacidad de resiliencia, se reconocen como factores esenciales para el logro de los objetivos del Convenio. | |||||||
| Global Climate - d. Hydrological cycle - Drought | State of the Climate 2017, Bulletin of the American Meteorological Society | Osborn, T.; Barichivich, J.; Harris, I.; Schrier, G.; Jones, P. | 2018 | Cambio de Uso de Suelo | 10.1175/2018BAMSStateoftheClimate.1 | http://journals.ametsoc.org/doi/10.1175/2018BAMSStateoftheClimate.1 | S36-S37 | Vol: 99 Issue: 8 | 0003-0007 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Hydrological drought results from a period of abnormally low precipitation, sometimes exacerbated by additional evapotranspiration (ET), and its occurrence can be apparent in reduced river discharge, soil moisture, and/or groundwater storage, depending on season and duration of the event. Here, an estimate of drought called the self-calibrating Palmer drought severity index (scPDSI; Wells et al. 2004; van der Schrier et al. 2013) is presented, using precipitation and Penman–Monteith potential ET from an early update of the CRU TS 3.26 dataset (I. Harris et al. 2014). Moisture categories are calibrated over the complete 1901–2017 period to ensure that “extreme” droughts and pluvials relate to events that do not occur more frequently than in approximately 2% of the months. This affects direct comparison with other hydrological cycle variables in Plate 2.1s that use a different base period. |
| Adding new evidence to the attribution puzzle of the recent water shortage over São Paulo (Brazil) | Tellus A: Dynamic Meteorology and Oceanography | Pattnayak, K.; Gloor, E.; Tindall, J.; Brienen, R.; Barichivich, J.; Baker, J.; Spracklen, D.; Cintra, B.; Coelho, C. | 2018 | Cambio de Uso de Suelo | 10.1080/16000870.2018.1481690 | https://www.tandfonline.com/doi/full/10.1080/16000870.2018.1481690 | 1-14 | Vol: 70 Issue: 1 | 1600-0870 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | View references (44) São Paulo, Brazil has experienced severe water shortages and record low levels of its water reservoirs in 2013–2014. We evaluate the contributions of Amazon deforestation and climate change to low precipitation levels using a modelling approach, and address whether similar precipitation anomalies might occur more frequently in a warming world. Precipitation records from INMET show that the dry anomaly extended over a fairly large region to the north of São Paulo. Unique features of this event were anomalous sea surface temperature (SST) patterns in the Southern Atlantic, an extension of the sub tropical high into the São Paulo region and moisture flux divergence over São Paulo. The SST anomalies were very similar in 2013/14 and 2014/15, suggesting they played a major role in forcing the dry conditions. The SST anomalies consisted of three zonal bands: a cold band in the tropics, a warm band to the south of São Paulo and another cold band poleward of 40 S. We performed ensemble climate simulations with observed SSTs prescribed, vegetation cover either fixed at 1870 levels or varying over time, and greenhouse gases (GHGs) either fixed at pre-industrial levels (280 ppm CO2) or varying over time. These simulations exhibit similar precipitation deficits over the São Paulo region in 2013/14. From this, we infer that SST patterns and the associated large-scale state of the atmosphere were important factors in determining the precipitation anomalies, while deforestation and increased GHGs only weakly modulated the signal. Finally, analyses of future climate simulations from CMIP5 models indicate that the frequency of such precipitation anomalies is not likely to change in a warmer climate. © 2018, © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. |
| Chronology, stratigraphy and hydrological modelling of extensive wetlands and paleolakes in the hyperarid core of the Atacama Desert during the late quaternary | Quaternary Science Reviews | Pfeiffer, M.; Latorre, C.; Santoro, C.; Gayo, E.; Rojas, R.; Carrevedo, M.; McRostie, V.; Finstad, K.; Heimsath, A.; Jungers, M.; De Pol-Holz, R.; Amundson, R. | 2018 | Cambio de Uso de Suelo; Ciudades Resilientes | 10.1016/j.quascirev.2018.08.001 | https://linkinghub.elsevier.com/retrieve/pii/S0277379117310521 | 224-245 | Vol: 197 | 0277-3791 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The halite-encrusted salt pans (salars) present at low elevations of the hyperarid core of the Atacama Desert in northern Chile are unique features of one of the driest and possibly oldest deserts on Earth. Here we show that these landscapes were shallow freshwater lakes and wetlands during the last glacial period, periodically between ~46.9 ka and 7.7 ka. The moisture appears to have been sourced from increased Andean runoff and most of our chronologies for these deposits were coeval with the Central Andean Pluvial Event (17.5-14.2 ka and 13.8-9.7 ka), but we also find evidence for older as well as slightly younger wet phases. These environments supported a diverse hygrophyte vegetation, as well as an array of diatoms, ostracods and gastropods. Using a regional hydrological model, we estimate that recharge rates from 1.5 to 4 times present were required to activate and maintain these wetlands in the past. Activation in the late Pleistocene was part of a regional enhancement of water resources, extending from the Andes, downstream and through riparian corridors, to the lowest and most arid portions of the desert itself. This fundamentally unique environment was encountered by the earliest human explorers in the region, and most likely facilitated migration and encampments on a landscape that at present lacks macroscopic life on its surface. |
| First evidence of a mid-Holocene earthquake-triggered megaturbidite south of the Chile Triple Junction | Sedimentary Geology | Piret, L.; Bertrand, S.; Kissel, C.; De Pol-Holz, R.; Tamayo Hernando, A.; Van Daele, M. | 2018 | Cambio de Uso de Suelo | 10.1016/j.sedgeo.2018.01.002 | https://linkinghub.elsevier.com/retrieve/pii/S0037073818300113 | 120-133 | Vol: 375 | 00370738 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Megaturbidites have been the focus of many paleoseismic and paleoenvironmental studies because they can provide evidence for catastrophic and/or hazardous events with potentially major environmental implications. During a recent research cruise in Baker Fjord, Chile (47°54′S–74°30′W), a megaturbidite was described between the Northern and Southern Patagonian Icefields. Here, we aim to determine the depositional processes of the megaturbidite and identify its origin. Based on the turbidite's location, a possible origin was the early Holocene drainage of paleo-lake General Carrera, which was recently proposed in the literature as having produced a Glacial Lake Outburst Flood (GLOF) that drained through Baker Fjord. Due to the fjord's location in a subduction zone, and close to the Chile Triple Junction, however, seismic activity must also be considered as a potential triggering mechanism. To achieve our goals, we undertook a multi-proxy analysis of sediment core MD07-3121, including sedimentology (grain size, loss-on-ignition, foraminifera counts), magnetic properties, bulk organic geochemistry, and radiocarbon dating, and we analysed bathymetric maps and sub-bottom profiles. Our grain-size results display a diagnostic fining upward trend and show evidence of seiching in the 733-cm-thick megaturbidite. The age of the event (5513–5211 cal yr BP) contradicts the hypothesis of an early Holocene GLOF origin. Bulk organic geochemical results indicate that the sediments that compose the turbidite are clearly of marine origin, which further goes against a GLOF origin. In addition, the megaturbidite is underlain by a 1136 cm thick mass transport deposit (MTD), also composed of marine sediments. According to the sub-bottom profiles, the MTD and the megaturbidite originate from the reworking of thick packages of sediment previously deposited on nearby sills and on the fjord's flanks. Furthermore, similar coeval deposits are found in an adjacent sub-basin. We therefore interpret these deposits to be triggered by an earthquake during the late mid-Holocene. While megathrust and intraslab earthquakes are possible in the region, we argue that a crustal earthquake is the most likely seismic trigger in the study area. This study reveals the first earthquake-triggered megaturbidite south of the Chile Triple Junction. |
| Simulaciones climáticas regionales | Rojas, M.; Gallardo, L.; Bozkurt, D. | 2018 | Agua y Extremos; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://cambioclimatico.mma.gob.cl/wp-content/uploads/2020/05/Simulaciones-climaticas-regionales-2018.pdf | 27 | Spanish | El Ministerio del Medio Ambiente contrató en 2016 el presente estudio a un equipo multidisciplinario del Centro de Ciencia del Clima y la Resiliencia (CR)2 a través de la Facultad de Ciencias Físicas y Matemáticas de la Universidad de Chile, el que fue desarrollado durante el año 2017. El propósito del proyecto fue generar proyecciones climáticas para Chile a través de la modelación climática a escala regional. Dicha información busca aportar a la correcta estimación de la vulnerabilidad del país, y está disponible en una plataforma interactiva que permite apoyar el diseño de políticas públicas. Este informe de síntesis presenta los resultados del análisis de los estudios de vulnerabilidad socio-ambiental del país, y plantea una propuesta conceptual y un protocolo de estandarización para este tipo de estudios, además de algunas consideraciones generales y recomendaciones basadas en la revisión de la literatura existente sobre la vulnerabilidad de distintos sectores y ámbitos territoriales y tecnológicos del país frente al cambio climático, así como las principales vulnerabilidades institucionales y brechas de conocimiento. | ||||||
| Guía de referencia para la plataforma de visualización de simulaciones climáticas | Rojas, M.; Gallardo, L.; Muñoz, F.; Valdebenito, N. | 2018 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://cambioclimatico.mma.gob.cl/wp-content/uploads/2020/05/Guia-para-la-Plataforma-de-visualizacion-de-simulaciones-climaticas.pdf | 38 | Spanish | El Ministerio del Medio Ambiente contrató en 2016 el presente estudio a un equipo multidisciplinario del Centro de Ciencia del Clima y la Resiliencia (CR)2 a través de la Facultad de Ciencias Físicas y Matemáticas de la Universidad de Chile, el que fue desarrollado durante el año 2017. El propósito del estudio consistió en generar información de proyecciones climáticas para Chile a través de la modelación climática a escala regional para la correcta estimación de la vulnerabilidad del país, y que, a su vez, esté disponible en una plataforma interactiva que permita apoyar el diseño de políticas públicas del país. Este informe de síntesis sirve como guía de referencia para el uso de la plataforma de visualización de simulaciones (http://simulaciones.cr2.cl). El objetivo principal de la plataforma es proveer información de proyecciones climáticas a distintas instituciones de gobierno, comunidad científica y otros actores que lo requieran. La compilación y organización de las bases de datos grillados se realiza en la plataforma de almacenamiento del (CR)2 y es accesible de forma abierta en http://simulaciones.cr2.cl/descargas. La plataforma de visualización incluye resultados de simulaciones climáticas globales y regionales, realizadas por grupos en Chile y el extranjero, así como datos observacionales en formato grillado desarrollados por el (CR)2 y otros grupos e instituciones. La plataforma genera mapas, tablas, gráficos y series de tiempo para el dominio de Sudamérica, Chile y macrozonas de Chile predefinidas, así como para polígonos o puntos definidos en forma dinámica. Las palabras claves y algunos conceptos (marcados en color rojo) se definen en la sección IV: ‘Glosario de conceptos’, en tanto que las siglas (en azul) se encuentran en la sección V: ‘Siglas y acrónimos’. Las referencias bibliográficas se listan en la sección VI: ‘Referencias Bibliográficas’. | ||||||
| Marco de evaluación de la vulnerabilidad | Rojas, M.; Gallardo, L.; Urquiza, A.; Billi, M. | 2018 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | https://cambioclimatico.mma.gob.cl/wp-content/uploads/2020/05/Marco-de-evaluacion-de-vulnerabilidad.pdf | 30 | Spanish | El Ministerio del Medio Ambiente contrató en 2016 el presente estudio a un equipo multidisciplinario del Centro de Ciencia del Clima y la Resiliencia (CR)2 a través de la Facultad de Ciencias Físicas y Matemáticas de la Universidad de Chile, el que fue desarrollado durante el año 2017. El propósito del proyecto fue generar proyecciones climáticas para Chile a través de la modelación climática a escala regional. Dicha información busca aportar a la correcta estimación de la vulnerabilidad del país, y está disponible en una plataforma interactiva que permite apoyar el diseño de políticas públicas. Este informe de síntesis presenta los resultados del análisis de los estudios de vulnerabilidad socio-ambiental del país, y plantea una propuesta conceptual y un protocolo de estandarización para este tipo de estudios, además de algunas consideraciones generales y recomendaciones basadas en la revisión de la literatura existente sobre la vulnerabilidad de distintos sectores y ámbitos territoriales y tecnológicos del país frente al cambio climático, así como las principales vulnerabilidades institucionales y brechas de conocimiento. | ||||||
| Coupled human-climate signals on the fire history of upper Cachapoal Valley, Mediterranean Andes of Chile, since 1201 CE | Global and Planetary Change | Rozas, V.; Le Quesne, C.; Rojas-Badilla, M.; González, M.; González-Reyes, Á. | 2018 | Cambio de Uso de Suelo | 10.1016/j.gloplacha.2018.05.013 | https://linkinghub.elsevier.com/retrieve/pii/S0921818117304988 | 137-147 | Vol: 167 | 0921-8181 | Thomson Reuters ISI (SCIE) | English | The long-term history of fire regimes in the Mediterranean Andes of Chile is almost unknown. Subalpine woodlands of Austrocedrus chilensis include long-lived trees resilient to low-intensity fires, which can provide valuable tree-ring-based information about fire history. In this work, we performed an annually resolved multicentury reconstruction of past fires from fire-scar records identified in relict Austrocedrus wood found on steep highly-eroded and rocky slopes with coarser fuel structure in the upper Cachapoal Valley, central Andes of Chile. We compared this fire record with historical land-use changes and extensive reconstructions of regional precipitation and temperature, as well as large-scale climatic patterns. The highest fire frequencies were recorded in the Spanish settlement period (1541–1750), when land-clearing activities, cattle ranching, agriculture, and mining practices became widespread after the Spanish conquest. At an interannual time scale, fire occurrence and precipitation were unconnected during the Spanish settlement. By contrast, in the indigenous period (1200–1540), under the influence of the aboriginal Chiquillanes people, fires occurred in wet years with high vegetation productivity. In the livestock grazing period (1751–1950), when large cattle ranches were established, fires occurred in dry years after a wet year. Fires in this period were likely ignited under conditions of high fuel flammability to improve plant production and promote intensive livestock grazing. At a multidecadal time scale, fires were more frequent in cold periods throughout the whole record. These findings suggest that herbaceous fuel accumulation and flammability, modulated by climate variation and human land uses, were the main factors promoting fires spread in this Mediterranean subalpine area. Our research emphasizes the importance of relict Austrocedrus wood for fire history reconstruction and expands knowledge about fire regime shifts over the past eight centuries in southern South America. | |
| The Tarapacá Declaration: A waterless people is a dead people | Chungará (Arica) | Santoro, C.; Castro, V.; Capriles, J.; Barraza, J.; Correa, J.; Marquet, P.; McRostie, V.; Gayo, E.; Latorre, C.; Valenzuela, D.; Uribe, M.; de Porras, M.; Standen, V.; Angelo, D.; Maldonado, A.; Hamamé, E.; Jofré, D. | 2018 | Ciudades Resilientes | 10.4067/S0717-73562018000200169 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-73562018000200169&lng=en&nrm=iso&tlng=en | 0-0 | Vol: 50 Issue: 2 | 0717-7356 | Thomson Reuters ISI (SSCI) | All Open Access; Gold Open Access | English | “The Tarapacá Declaration” draws attention to the urgent need to change how human societies have been using water in the Atacama Desert, based on a historical trajectory spanning several millennia. The Declaration, an initiative that summarizes the results of the CONICYT/PIA, Anillo project SOC1405, is oriented towards civil society and various political entities, aiming to generate technological and cultural changes to halt and mitigate the effects caused by anthropogenic activities in one of the oldest and most arid deserts in the world. In the course of the project, we established the urgent need to sensitize society to the wasteful overuse and misuse of water in the Atacama Desert, a non-renewable resource in relation to the economic scales of extraction of this element that depends, fundamentally, on fossil waters that have accumulated for millennia in the highlands of the Desert. In this way we want to avoid that this scientific knowledge is encapsulated in the universities and to echo the point made by Victoria Castro (2003): that to grow you have to educate. |
| The meanings of participation for climate change in Chile | Ambiente y Desarrollo | Sapiains Arrué, R.; Ugarte Caviedes, A.; Aldunce, P. | 2018 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.11144/Javeriana.ayd21-41.spcc | http://revistas.javeriana.edu.co/index.php/ambienteydesarrollo/article/view/22189 | 43-60 | Vol: 21 Issue: 41 | 2346-2876, 0121-7607 | Thomson Reuters ISI (ESCI) | Spanish | This article analyzes the different meanings of the concept of participation, to move towards a more inclusive model of climate change governance in Chile. For this, a bibliographic review is presented that discusses different epistemologies, theories and definitions of participation, with emphasis on the difficulties for its implementation in the Chilean context. Subsequently, the citizen participation mechanisms deployed in the development of existing climate change governance instruments in Chile are reviewed. Types of participation used are distinguished and experiences conducted from civil society and academia are identified. Finally, the scope and limitations of the participation models implemented are discussed and the importance of increasing the influence of civil society and improving existing mechanisms is highlighted. This is explained by a climate change scenario that will possibly require a greater number of actors involved in decision-making, to anticipate possible divisions in the face of the development of more radical adaptation or mitigation actions, and that at the same time will demand higher levels of responsibility. , commitment and action of citizenship. | |
| Assessment of methane and carbon dioxide emissions in two sub-basins of a small acidic bog lake artificially divided 30 years ago | Freshwater Biology | Sepulveda-Jauregui, A.; Martinez-Cruz, K.; Lau, M.; Casper, P. | 2018 | Zonas Costeras | 10.1111/fwb.13182 | http://doi.wiley.com/10.1111/fwb.13182 | 1534-1549 | Vol: 63 Issue: 12 | 0046-5070 | Thomson Reuters ISI (SCIE) | English | Although lakes are important sources of methane (CH4) and carbon dioxide (CO2) to the atmosphere contributing to global warming, their CH4 and CO2 emissions are rarely assessed. In particular, increasing inputs of terrestrial dissolved organic carbon (DOC) may affect gas dynamics and alter seasonal changes in gas production. Here, we analysed variations in CH4 and CO2 dynamics in sub-basins of an acidic bog lake, which was artificially divided into four quarters three decades ago, leading to divergence in water chemistry and biology. In the divided lake, only the south-west basin (SW) received DOC inputs from an adjacent peat bog, while the north-east basin (NE) was hydrologically disconnected. A year-long determination of CH4 and CO2 production and emission patterns in the two contrasting basins exposed the indirect mechanisms by which DOC supply exercised control on greenhouse gas dynamics in this shallow lake. In both basins, dissolved CH4 was negatively correlated with dissolved oxygen (O2) through the water column, suggesting that aerobic methanotrophy is an important regulator of CH4 emissions in this lake. In contrast, the amount of CO2 stored in oxic and anoxic layers was not significantly different between the basins, suggesting that O2 is not the most important driver of dissolved CO2. Estimated total CH4 and CO2 emissions were 2.1 and 1.7 times lower in the NE basin than in the SW basin, with major CH4 and CO2 emissions occurring during the fall turnover. The differences in CH4 and CO2 emissions suggest that the hydro-physical properties, namely seasonal temperature, the duration of stratification and O2 availability, are the main drivers of CH4 and CO2 emissions to the atmosphere from small shallow lakes under the influence of DOC inputs under global warming pressure. | |
| In and out of glacial extremes by way of dust climate feedbacks | Proceedings of the National Academy of Sciences | Shaffer, G.; Lambert, F. | 2018 | Ciudades Resilientes | 10.1073/pnas.1708174115 | http://www.pnas.org/lookup/doi/10.1073/pnas.1708174115 | 2026-2031 | Vol: 115 Issue: 9 | 0027-8424 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Mineral dust aerosols cool Earth directly by scattering incoming solar radiation and indirectly by affecting clouds and biogeochemical cycles. Recent Earth history has featured quasi-100,000-y, glacial−interglacial climate cycles with lower/higher temperatures and greenhouse gas concentrations during glacials/interglacials. Global average, glacial maxima dust levels were more than 3 times higher than during interglacials, thereby contributing to glacial cooling. However, the timing, strength, and overall role of dust−climate feedbacks over these cycles remain unclear. Here we use dust deposition data and temperature reconstructions from ice sheet, ocean sediment, and land archives to construct dust−climate relationships. Although absolute dust deposition rates vary greatly among these archives, they all exhibit striking, nonlinear increases toward coldest glacial conditions. From these relationships and reconstructed temperature time series, we diagnose glacial−interglacial time series of dust radiative forcing and iron fertilization of ocean biota, and use these time series to force Earth system model simulations. The results of these simulations show that dust−climate feedbacks, perhaps set off by orbital forcing, push the system in and out of extreme cold conditions such as glacial maxima. Without these dust effects, glacial temperature and atmospheric CO2 concentrations would have been much more stable at higher, intermediate glacial levels. The structure of residual anomalies over the glacial−interglacial climate cycles after subtraction of dust effects provides constraints for the strength and timing of other processes governing these cycles. |
| Temporal Variability in Net Primary Production in an Upwelling Area off Central Chile (36°S) | Frontiers in Marine Science | Testa, G.; Masotti, I.; Farías, L. | 2018 | Zonas Costeras | 10.3389/fmars.2018.00179 | https://www.frontiersin.org/article/10.3389/fmars.2018.00179/full | art: 179 | Vol: 5 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | The temporal variability of Net Primary Production (NPP) off central Chile (36°S, 73°W), an area subjected to seasonal coastal upwelling, was analyzed using monthly in situ 13C incubations within the photic zone, along with bio-oceanographic variables from a fixed time series station; and satellite NPP estimations (NPPE) from the Vertically Generalized Production Model between 2006 and 2015. NPP and NPPE rates varied from 0.03 to 18.29 and from 0.45 to 9.07 g C m−2 d−1, respectively. Both rates were fairly well correlated with each other (r2 = 0.61), but when these data were separated into two periods, higher r2 value was found during winter (r2 = 0.70) with respect to the rest of the year (r2 = 0.24); the latter correlation was partially due to increased weekly NPPE variability during active and relaxed upwelling events. NPP rates along with other biophysical variables allowed for a division of the annual cycle into three distinct periods: September to January (high productivity, mean integrated NPP rates of 4.0 g C m−2 d−1), February to March (intermediate productivity, mean integrated NPP rates of 1.4 g C m−2 d−1), and May to August (basal level, mean integrated NPP rates of 0.5 g C m−2 d−1). NPP appeared to be partially controlled by nutrient inputs, either from upwelling (September-April) and river discharge (May-August), maintaining high NPP rates throughout the entire year, with an annual mean NPP rate of 1.1 kg C m−2 yr−1. In this region, El Niño Southern Oscillation events did not appear to impact the NPP interannual variability. |
| Entangling the Forests and the Communities: Territorialization of REDD+ in the Common Land Felipe Carrillo Puerto, Mexico | Cuadernos de Desarrollo Rural | Tobasura Morales, D.; Gurri, F.; Blanco Wells, G.; Schmook, B. | 2018 | Gobernanza e Interfaz Ciencia y Política | 10.11144/Javeriana.cdr15-81.ebct | https://revistas.javeriana.edu.co/index.php/desarrolloRural/article/view/22214 | 1-18 | Vol: 15 Issue: 81 | 0122-1450 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | Spanish | We analyzed the discursive and relational effects of the pilot project 'Reduction of Emissions due to Deforestation and Forest Degradation' (REDD+) in domestic units both entitled and not entitled to land access in the common land Felipe Carrillo Puerto, Quintana Roo. Based on semi-structured surveys and interviews, we identified those mechanisms favoring the adoption of preservation practices by the common land owner-residents while restricting the traditional forest management. These dynamics bring about changes in the subsistence strategies of the domestic units and limit the participation and benefit distribution to women, the youth, and settlers who do not own the land |
| AOT Retrieval Procedure for Distributed Measurements With Low-Cost Sun Photometers: AOT RETRIEVAL METHOD FOR SUN PHOTOMETERS | Journal of Geophysical Research: Atmospheres | Toledo, F.; Garrido, C.; Díaz, M.; Rondanelli, R.; Jorquera, S.; Valdivieso, P. | 2018 | Zonas Costeras | 10.1002/2017JD027309 | http://doi.wiley.com/10.1002/2017JD027309 | 1113-1131 | Vol: 123 Issue: 2 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | We propose a new application of inexpensive light-emitting diode (LED)-based Sun photometers, consisting of measuring the aerosol optical thickness (AOT) with high resolution within metropolitan scales. Previously, these instruments have been used at continental scales by the GLOBE program, but this extension is already covered by more expensive and higher-precision instruments of the AERONET global network. For this we built an open source two-channeled LED-based Sun photometer based on previous developments, with improvements in the hardware, software, and modifications on the calibration procedure. Among these we highlight the use of MODTRAN to characterize the effect introduced by using LED sensors in the AOT retrieval, an open design available for the scientific community and a calibration procedure that takes advantage of a CIMEL Sun photometer located within the city, enables the intercomparison of several LED Sun photometers with a common reference. We estimated the root-mean-square error in the AOT retrieved by the prototypes as 0.006 at the 564 nm and 0.009 at the 408 nm. This error is way under the magnitude of the AOT daily cycle variability measured by us in our campaigns, even for distances closer than 15 km. In addition to inner city campaigns, we also show aerosol-tracing applications by measuring AOT variations from the city of Santiago to the Andes glaciers. Measuring AOT at high spatial resolution in urban areas can improve our understanding of urban scale aerosol circulation, providing information for solar energy planning, health policies, and climatological studies, among others. |
| Toward High-Resolution Vertical Measurements of Dissolved Greenhouse Gases (Nitrous Oxide and Methane) and Nutrients in the Eastern South Pacific | Frontiers in Marine Science | Troncoso, M.; Garcia, G.; Verdugo, J.; Farías, L. | 2018 | Zonas Costeras | 10.3389/fmars.2018.00148 | https://www.frontiersin.org/articles/10.3389/fmars.2018.00148/full | art: 148 | Vol: 5 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In this study, in situ, real-time and high-resolution vertical measurements of dissolved greenhouse gases (GHGs) such as nitrous oxide (N2O) and methane (CH4) and nutrients are reported for the eastern South Pacific (ESP); a region with marked zonal gradients, ranging from highly productive and suboxic conditions in coastal upwelling systems to oligotrophic and oxygenated conditions in the subtropical gyre. Four high-resolution vertical profiles for gases (N2O and CH4) and nutrients (NO−3 and PO3−4) were measured using a Pumped Profiling System (PPS), connected with a liquid degassing membrane coupled with Cavity Ring-Down Spectroscopy (CRDS) and a nutrient auto-analyzer, respectively. The membrane-CRDS system maintains a linear response over a wide range of gas concentrations, detecting N2O and CH4 levels as low as 0.0774 ± 0.0004 and 0.1011 ± 0.001 ppm, respectively. Continuous profiles for gases and nutrients were similar to those reported throughout the ESP, with pronounced N2O and CH4 peaks at the upper oxycline and at the base of the euphotic zone and pycnocline, respectively, in the coastal zone; but almost constant depth profiles in the subtropical gyre. Additionally, other vertical gas and nutrient structures were observed using continuous sampling, which would not have been detected by discrete sampling. Our results demonstrate that continuous measurements can be a potentially useful methodology for future GHGs cycle studies. |
| Sociología económica y teoría de sistemas: Sobre La economía de la sociedad de Niklas Luhmann | Cuadernos de Teoría Social | Urquiza Gómez, A. | 2018 | Ciudades Resilientes | http://culturadigital.udp.cl/index.php/documento/cuaderno-de-teoria-social-n6-la-inquietud-en-los-conceptos-teoria-social-en-primera-persona/ | Vol: 3 Issue: 6 | |||||||
| The Role of Qualitative Approaches in Developing Long-Term Strategies | World Resources Institute | Urquiza, A. | 2018 | Ciudades Resilientes | temporal and spatial evaluation | Climate change is an unprecedented global problem that forces global society to confront the unexpected consequences of its own development. It is a problem whose complexity manifests in at least three dimensions. First, climate change encompasses many variables (atmospheric, geological, demographic, economic, etc.) with different qualities: qualitative (dichotomous or polysomic, nominal or ordinal), quantitative (discrete or continuous), intervening, moderating, independent, or dependent. Each requires the implementation of diverse strategies in different and even opposed areas. Second, the relationships between these variables are selective, that is, when looking at the problem, it has not been feasible (and hardly ever is) to consider all the possible variables, much less to establish inclusion or exclusion criteria for them. Thus, for example, we have phenomena whose independent variables are global (such as global warming) but whose dependent variables are distributed unequally on the planet (such as local disasters). We find the same, nolens volens, for local independent variables (such as the dumping of waste in the seas) whose impacts cross national borders. Third, climate change is a problem that manifests itself differently but simultaneously on the planet. It requires longer time horizons than those that frame economic or political decisions, as well as coordination between different sectors of the society. In short, the dimensions in which climate change manifests the diversity of elements, the selectivity of relationships, and the differentiation in social systems, they configure it as a complex problem. (Luhmann 1986). The accumulation of quantitative measurements of climate change has fed a rich discussion, but little progress has been made in complementing these measurements with qualitative methods of research and social intervention, which in other contexts have shown their usefulness in collecting relevant information to surmount obstacles of social coordination or lack of reflexivity. In this sense, the social sciences deserve special attention, given that they have been overlooked in the past and possess qualities that can fruitfully support the global response to climate change. This essay will address this issue by considering the areas exposed and visualizing how these tools can contribute to the development of long-term visions that confront one of the greatest challenges facing humanity in the 21st century. |
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| Metalogue as a transdisciplinary collaboration tool | Cinta moebio | Urquiza, A.; Amigo, C.; Billi, M.; Brandao, G.; Morales, B. | 2018 | Ciudades Resilientes | 10.4067/S0717-554X2018000200182 | https://doi.org/10.4067/S0717-554X2018000200182 | 182-198 | Vol: 62 | 0717-554X | Thomson Reuters ISI (ESCI) | All Open Access; Gold Open Access | Spanish | Contemporary society shows an increasing demand for participatory instances able to effectively foster the collaboration of diverse organizational, disciplinary and socio-cultural areas. The challenges intrinsic to such participatory instancesrequire the development of methodologies that may allow for the insertion of reflexivity within the dialogical interaction, while also promoting the collective construction of "boundary objects": such objects, in turn, by serving as a common reference for the different perspectives involved in the dialogue, have the potential of facilitating the future collaboration among such perspectives. To respond to these demands -and inspired by the notion of metalogue originally introduced by Gregory Bateson- this paper elaborates a systemic-constructivist proposal of observation and contextual intervention, aimed at fostering reflexivity within dialogical-participatory instances by inducing their participants to perform a second-order observation of the distinctions mobilized within the interaction. Building upon this reflexivity, the metalogue pursues the co-construction of documents able to coordinate the perspectives of the participants and the expectations of the structural and organizational arrangements in which they operate. In addition to justifying and describing the technique of the metalogue, the paper highlights some lessons learned, good practices and proposals derived from its application in various transdisciplinary experiences in Chile. |
| Participatory Energy Transitions as Boundary Objects: The Case of Chile's Energía2050 | Frontiers in Energy Research | Urquiza, A.; Amigo, C.; Billi, M.; Espinosa, P. | 2018 | Ciudades Resilientes | 10.3389/fenrg.2018.00134 | https://www.frontiersin.org/article/10.3389/fenrg.2018.00134/full | art: 134 | Vol: 6 | 2296-598X | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | This paper analyzes the use of “participatory futures” within the context of energy transition, paying special attention to the case of Chile's long-term energy policy. Our main aim is to question the role of “participation” in such a context and particularly, to decouple the operative function of participation from its normative function. Structurally, we argue that the construction of a joint vision of desired energy futures must be understood as a deliberate attempt at governing the energy transition by way of governing the expectations of the actors and systems involved in it. Participatory approaches can promote the co-construction of such energy futures in the form of a boundary-object, able to resonate with and provide a common reference to the actors participating in its creation. On the other hand, participatory approaches can also be a way to make transitions more democratic, subjecting it to a broader influence and control from the citizenship. These two functions of “participation” are always potentially at odds with one another. Democratizing the transition, in fact, would require producing plural, dynamical imaginaries that are responsive and accountable to the public. On the contrary, the need to make transitions governable may close-up such imaginaries and narrow-down the participatory efforts to foster their normalization and acceptability on the part of the most influential actors in the self-government of the transition. To refine and exemplify our proposal, we perform a qualitative, exploratory case study of Chile's E2050 energy policy. Our findings show that “participation” may indeed have been used in the case to align partially conflicting expectations around a collectively-defined boundary object which may then act as a form of contextual, anticipatory and polycentric governance of the transition. However, from a democratic perspective, E2050 appears as a tokenization of the public in support of a pre-eminently technical and monolithic vision enacted by the Energy Ministry and the Consultative Committee. Within this context, the actual influence of the public on the policy and the possibility for political contestation are much more questionable. |
| Climate variability and forest fires in central and south-central Chile | Ecosphere | Urrutia-Jalabert, R.; González, M.; González-Reyes, Á.; Lara, A.; Garreaud, R. | 2018 | Agua y Extremos; Cambio de Uso de Suelo | 10.1002/ecs2.2171 | http://doi.wiley.com/10.1002/ecs2.2171 | e02171 | Vol: 9 Issue: 4 | 2150-8925 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | This paper evaluates the relationship between fire occurrence (number and burned area) and climate variability (precipitation and maximum temperatures) across central and south-central Chile (32°–43° S) during recent decades (1976–2013). This region sustains the largest proportion of the Chilean population, contains ecologically important remnants of endemic ecosystems, the largest extension of forest exotic plantations, and concentrates most of the fire activity in the country. Fire activity in central Chile was mainly associated with above-average precipitation during winter of the previous year and with dry conditions during spring to summer. The later association was particularly strong in the southern, wetter part of the study region. Maximum temperature had a positive significant relationship with burned area across the study region, with stronger correlations toward the south. Fires in central Chile were significantly related to El Nino~ –Southern Oscillation, through rainfall anomalies during the year previous to the fire season. The Antarctic Oscillation during winter through summer was positively related to fires across the study area due to drier/warmer conditions associated with the positive polarity of this oscillation. Climate change projections for the region reveal an all-season decrease in precipitation and increases in temperature, that may likely result in an increment of the occurrence and the area affected by fires, as it has been observed during a multi-year drought afflicting central Chile since 2010. |
| Elucidating the hydraulic vulnerability of the longest-lived Southern Hemisphere conifer to aridification | Forest Ecology and Management | Urrutia-Jalabert, R.; Peña, M.; Coopman, R.; Carvajal, D.; Jiménez-Castillo, M.; Lara, A.; Cosimo, D.; Lobos-Catalán, P. | 2018 | Cambio de Uso de Suelo | 10.1016/j.foreco.2018.08.027 | https://linkinghub.elsevier.com/retrieve/pii/S037811271830793X | 472-484 | Vol: 430 | 0378-1127 | Thomson Reuters ISI (SCIE) | English | Drier climatic conditions will be the future scenario in many regions worldwide, including southern South America. Few studies have characterized the ecophysiological vulnerability of the endemic tree species that inhabit this area, to climate change. In this study we assessed the hydraulic vulnerability of the longest-lived tree of the Southern Hemisphere, Fitzroya cupressoides, focusing on adult trees and saplings from two highly disturbed populations: the Coastal Range (AC) and Central Depression (FN) of southern Chile, which represent contrasting site conditions. This, as a basis for the design of conservation strategies to safeguard the persistence of these endangered forests in a drier future. We assessed water potentials (WP) throughout a growing season, their relationships with environmental conditions, as well as leaf and stem (branch) traits and hydraulic safety margins. Despite that the studied summer was the second driest in the last seven decades, minimum WP were not that negative (−1.3 to −1.5 MPa); which could be partly explained by a high leaf capacitance in this species. Adult trees and saplings from both sites did not significantly differ in their WP at turgor loss point, and their associated leaf safety margins, which were relatively low in all cases. However, they significantly differed in the xylem WP causing a 50% loss of stem conductivity (P50): adults AC: −5.14, saplings AC: −2.53, adults FN: −3.71, and saplings FN: −3.87 MPa. These values led to a relatively large stem safety margin (SSM) in most cases, and their variation was not explained neither by wood density, nor by tracheid size changes. Moreover, there appears to be an ontogenic adjustment in the more restrictive site AC, which was not seen in FN. Within the continuum of species strategies to cope with water stress, Fitzroya has features of the two ends of the continuum: tissues with large SSM, and tissues that sustain milder operation pressures through capacitance. Although Fitzroya appears to be relatively resistant to water scarcity, saplings from AC, seem to be the most vulnerable to the aridification trend in southern Chile. Moreover, future drying could become a significant extra threat to the highly endangered Central Depression population. Conservation actions are urgently needed to secure the future of Fitzroya forests in southern Chile. | |
| Terrain-Trapped Airflows and Orographic Rainfall along the Coast of Northern California. Part II: Horizontal and Vertical Structures Observed by a Scanning Doppler Radar | Monthly Weather Review | Valenzuela, R.; Kingsmill, D. | 2018 | Agua y Extremos | 10.1175/MWR-D-17-0227.1 | http://journals.ametsoc.org/doi/10.1175/MWR-D-17-0227.1 | 2381-2402 | Vol: 146 Issue: 8 | 0027-0644 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | This study documents the mean properties and variability of kinematic and precipitation structures associated with orographic precipitation along the coast of Northern California in the context of terrain-trapped airflows (TTAs). TTAs are defined as relatively narrow air masses that consistently flow in close proximity and approximately parallel to an orographic barrier. Seven land-falling winter storms are examined with observations from a scanning X-band Doppler radar deployed on the coast at Fort Ross, California. Additional information is provided by a 915-MHz wind-profiling radar, surface meteorology, a GPS receiver, and balloon soundings. The composite kinematic structure during TTA conditions exhibits a significant horizontal gradient of wind direction from the coast to approximately 50 km offshore and a low-level jet (LLJ) that surmounts a weaker airflow offshore corresponding to the TTA, with a zone of enhanced precipitation evident between ~5 and 25 km offshore and oriented nearly parallel to the coastline. Conversely, the composite kinematic structure during NO-TTA conditions exhibits a smaller offshore horizontal gradient of wind direction and precipitation structures are generally enhanced within ~15 km of the coastline. Interstorm variability analysis reveals significant variations in kinematic structures during both TTA and NO-TTA conditions, whereas significant variations in precipitation structures are only evident during TTA conditions. The interstorm analysis also illustrates more clearly how LLJ vertical structures evident during NO-TTA conditions exhibit ascent along the coast and over the coastal mountains, which is in contrast to TTA conditions where the ascent occurs offshore and over the TTA. |
| Influence of Glacier Melting and River Discharges on the Nutrient Distribution and DIC Recycling in the Southern Chilean Patagonia | Journal of Geophysical Research: Biogeosciences | Vargas, C.; Cuevas, L.; Silva, N.; González, H.; De Pol-Holz, R.; Narváez, D. | 2018 | Cambio de Uso de Suelo | 10.1002/2017JG003907 | http://doi.wiley.com/10.1002/2017JG003907 | 256-270 | Vol: 123 Issue: 1 | 2169-8953 | Thomson Reuters ISI (SCIE) | English | The Chilean Patagonia constitutes one of the most important and extensive fjord systems worldwide, therefore can be used as a natural laboratory to elucidate the pathway of both organic and inorganic matter in the receiving environment. In this study we use data collected during an intensive oceanographic cruise along the Magellan Strait into the Almirantazgo Fjord in southern Patagonia to evaluate how different sources of dissolved inorganic carbon (DIC) and recycling may impact particulate organic carbon (POC) δ13C and influence the nutrients and carbonate system spatial distribution. The carbonate system presented large spatial heterogeneity. The lowest total alkalinity and DIC were associated to freshwater dilution observed near melting glaciers. The δ13CDIC analysis suggests that most DIC in the upper 50 m depth was not derived from terrestrial organic matter remineralization. 13C-depleted riverine and ice-melting DIC influence the DIC pool along the study area, but due to that DIC concentration from rivers and glaciers is relatively low, atmospheric carbon contribution or biological processes seem to be more relevant. Intense undersaturation of CO2 was observed in high chlorophyll waters. Respired DIC coming from the bottom waters seems to be almost insignificant for the inorganic carbon pool and therefore do not impact significantly the stable carbon isotopic composition of dissolved organic carbon and POC in the upper 50 m depth. Considering the combined effect of cold and low alkalinity waters due to ice melting, our results highlight the importance of these processes in determining corrosive waters for CaCO3 and local acidification processes associated to calving glacier in fjord ecosystems. | |
| Impacts of Atmospheric Rivers on Precipitation in Southern South America | Journal of Hydrometeorology | Viale, M.; Valenzuela, R.; Garreaud, R.; Ralph, F. | 2018 | Agua y Extremos | 10.1175/JHM-D-18-0006.1 | http://journals.ametsoc.org/doi/10.1175/JHM-D-18-0006.1 | 1671-1687 | Vol: 19 Issue: 10 | 1525-755X | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | This study quantifies the impact of atmospheric rivers (ARs) on precipitation in southern South America. An AR detection algorithm was developed based on integrated water vapor transport (IVT) from 6-hourly CFSR reanalysis data over a 16-yr period (2001-16). AR landfalls were linked to precipitation using a comprehensive observing network that spanned large variations in terrain along and across the Andes from 27° to 55°S, including some sites with hourly data. Along the Pacific (west) coast, AR landfalls are most frequent between 38° and 50°S, averaging 35-40 days yr-1. This decreases rapidly to the south and north of this maximum, as well as to the east of the Andes. Landfalling ARs are more frequent in winter/spring (summer/fall) to the north (south) of ~43°S. ARs contribute 45%-60% of the annual precipitation in subtropical Chile (37°-32°S) and 40%-55% along the midlatitude west coast (37°-47°S). These values significantly exceed those in western North America, likely due to the Andes being taller. In subtropical and midlatitude regions, roughly half of all events with top-quartile precipitation rates occur under AR conditions. Median daily and hourly precipitation in ARs is 2-3 times that of other storms. The results of this study extend knowledge of the key roles of ARs on precipitation, weather, and climate in the South American region. They enable comparisons with other areas globally, provide context for specific events, and support local nowcasting and forecasting. © 2018 American Meteorological Society. |
| An intercomparison of oceanic methane and nitrous oxide measurements | Biogeosciences | Wilson, S.; Bange, H.; Arévalo-Martínez, D.; Barnes, J.; Borges, A.; Brown, I.; Bullister, J.; Burgos, M.; Capelle, D.; Casso, M.; de la Paz, M.; Farías, L.; Fenwick, L.; Ferrón, S.; Garcia, G.; Glockzin, M.; Karl, D.; Kock, A.; Laperriere, S.; Law, C.; Manning, C.; Marriner, A.; Myllykangas, J.; Po... | 2018 | Zonas Costeras | 10.5194/bg-15-5891-2018 | https://www.biogeosciences.net/15/5891/2018/ | 5891-5907 | Vol: 15 Issue: 19 | 1726-4189 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Large-scale climatic forcing is impacting oceanic biogeochemical cycles and is expected to influence the water-column distribution of trace gases, including methane and nitrous oxide. Our ability as a scientific community to evaluate changes in the water-column inventories of methane and nitrous oxide depends largely on our capacity to obtain robust and accurate concentration measurements that can be validated across different laboratory groups. This study represents the first formal international intercomparison of oceanic methane and nitrous oxide measurements whereby participating laboratories received batches of seawater samples from the subtropical Pacific Ocean and the Baltic Sea. Additionally, compressed gas standards from the same calibration scale were distributed to the majority of participating laboratories to improve the analytical accuracy of the gas measurements. The computations used by each laboratory to derive the dissolved gas concentrations were also evaluated for inconsistencies (e.g., pressure and temperature corrections, solubility constants). The results from the intercomparison and intercalibration provided invaluable insights into methane and nitrous oxide measurements. It was observed that analyses of seawater samples with the lowest concentrations of methane and nitrous oxide had the lowest precisions. In comparison, while the analytical precision for samples with the highest concentrations of trace gases was better, the variability between the different laboratories was higher: 36% for methane and 27% for nitrous oxide. In addition, the comparison of different batches of seawater samples with methane and nitrous oxide concentrations that ranged over an order of magnitude revealed the ramifications of different calibration procedures for each trace gas. Finally, this study builds upon the intercomparison results to develop recommendations for improving oceanic methane and nitrous oxide measurements, with the aim of precluding future analytical discrepancies between laboratories. |
| Modelling Climate and Societal Resilience in the Eastern Mediterranean in the Last Millennium | Human Ecology | Xoplaki, E.; Luterbacher, J.; Wagner, S.; Zorita, E.; Fleitmann, D.; Preiser-Kapeller, J.; Sargent, A.; White, S.; Toreti, A.; Haldon, J.; Mordechai, L.; Bozkurt, D.; Akçer-Ön, S.; Izdebski, A. | 2018 | Zonas Costeras | 10.1007/s10745-018-9995-9 | http://link.springer.com/10.1007/s10745-018-9995-9 | 363-379 | Vol: 46 Issue: 3 | 0300-7839, 1572-9915 | Thomson Reuters ISI (SSCI) | All Open Access; Hybrid Gold Open Access | English | This article analyses high-quality hydroclimate proxy records and spatial reconstructions from the Central and Eastern Mediterranean and compares them with two Earth System Model simulations (CCSM4, MPI-ESM-P) for the Crusader period in the Levant (1095–1290 CE), the Mamluk regime in Transjordan (1260–1516 CE) and the Ottoman crisis and Celâlî Rebellion (1580–1610 CE). During the three time intervals, environmental and climatic stress tested the resilience of complex societies. We find that the multidecadal precipitation and drought variations in the Central and Eastern Mediterranean cannot be explained by external forcings (solar variations, tropical volcanism); rather they were driven by internal climate dynamics. Our research emphasises the challenges, opportunities and limitations of linking proxy records, palaeoreconstructions and model simulations to better understand how climate can affect human history. |
| Seasonal drought effects on the water quality of the Biobío River, Central Chile | Environmental Science and Pollution Research | Yevenes, M.; Figueroa, R.; Parra, O. | 2018 | Zonas Costeras | 10.1007/s11356-018-1415-6 | http://link.springer.com/10.1007/s11356-018-1415-6 | 13844-13856 | Vol: 25 Issue: 14 | 0944-1344, 1614-7499 | Thomson Reuters ISI (SCIE) | English | Quantifying the effect of droughts on ecosystem functions is essential to the development of coastal zone and river management under a changing climate. It is widely acknowledged that climate change is increasing the frequency and intensity of droughts, which can affect important ecosystem services, such as the regional supply of clean water. Very little is understood about how droughts affect the water quality of Chilean high flow rivers. This paper intends to investigate the effect of an, recently identified, unprecedented drought in Chile (2010–2015), on the Biobío River water quality, (36°45′–38°49′ S and 71°00′–73°20′ W), Central Chile. This river is one of the largest Chilean rivers and it provides abundant freshwater. Water quality (water temperature, pH, dissolved oxygen, electrical conductivity, biological oxygen demand, total suspended solids, chloride, sodium, nutrients, and trace metals), during the drought (2010–2015), was compared with a pre-drought period (2000–2009) over two reaches (upstream and downstream) of the river. Multivariate analysis and seasonal Mann-Kendall trend analyses and a Theil-Sen estimator were employed to analyze trends and slopes of the reaches. Results indicated a significant decreased trend in total suspended solids and a slightly increasing trend in water temperature and EC, major ions, and trace metals (chrome, lead, iron, and cobalt), mainly in summer and autumn during the drought. The reduced variability upstream suggested that nutrient and metal concentrations were more constant than downstream. The results evidenced, due to the close relationship between river discharge and water quality, a slightly decline of the water quality downstream of the Biobío River during drought period, which could be attenuated in a post-drought period. These results displayed that water quality is vulnerable to reductions in flow, through historical and emerging solutes/contaminants and induced pH mobilization. Consequently, seasonal changes and a progressive reduction of river flow affect the ecosystem functionality in this key Chilean river. The outcomes from this research can be used to improve how low flow conditions and the effects of a reduction in the river volume and discharge are assessed, which is the case under the scenario of more frequent drought periods. | |
| Using the Weather Research and Forecasting (WRF) Model for Precipitation Forecasting in an Andean Region with Complex Topography | Atmosphere | Yáñez-Morroni, G.; Gironás, J.; Caneo, M.; Delgado, R.; Garreaud, R. | 2018 | Agua y Extremos | 10.3390/atmos9080304 | http://www.mdpi.com/2073-4433/9/8/304 | 304 | Vol: 9 Issue: 8 | 2073-4433 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Weather Research and Forecasting (WRF) model has been successfully used in weather prediction, but its ability to simulate precipitation over areas with complex topography is not optimal. Consequently, WRF has problems forecasting rainfall events over Chilean mountainous terrain and foothills, where some of the main cities are located, and where intense rainfall occurs due to cutoff lows. This work analyzes an ensemble of microphysics schemes to enhance initial forecasts made by the Chilean Weather Agency in the front range of Santiago. We first tested different vertical levels resolution, land use and land surface models, as well as meteorological forcing (GFS/FNL). The final ensemble configuration considered three microphysics schemes and lead times over three rainfall events between 2015 and 2017. Cutoff low complex meteorological characteristics impede the temporal simulation of rainfall properties. With three days of lead time, WRF properly forecasts the rainiest N-hours and temperatures during the event, although more accuracy is obtained when the rainfall is caused by a meteorological frontal system. Finally, the WSM6 microphysics option had the best performance, although further analysis using other storms and locations in the area are needed to strengthen this result. |
| Temporal and spatial evaluation of long-term satellite-based precipitation products across the complex topographical and climatic gradients of Chile | Remote Sensing and Modeling of the Atmosphere, Oceans, and Interactions VII | Zambrano-Bigiarini, M. | 2018 | Agua y Extremos | 10.1117/12.2513645 | https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10782/2513645/Temporal-and-spatial-evaluation-of-long-term-satellite-based-precipitation/10.1117/12.2513645.full | 27 | Vol: 10782 | Not indexed | English | Satellite-based rainfall estimates (SRE) have become a promising data source to overcome some limitations of ground-based rainfall measurements, in particular for hydrological and other environmental applications. This study evaluates the spatial and temporal performance of four long-term SRE products (TMPA 3B42v7, CHIRPSv2, MSWEPv1.1 and MSWEPv2.2) over the complex topography and climatic gradients of Chile. Time series of precipitation measured at 371 stations are compared against the corresponding grid cell of each SRE (in their original spatial resolution) at different temporal scales (daily, monthly, seasonal, annual). The modified Kling-Gupta efficiency along with its three individual components were used to assess the performance of each SRE, while two categorical indices (POD, and fBIAS) were used to evaluate the skill of each SRE to correctly capture different precipitation intensities. Results revealed that all SREs performed best in Central-Southern Chile (32.18-36.4°S), in particular at lowand mid-elevation zones (0-1000 m a.s.l.). Seasonally, all products performed best in terms of KGE0 during the wet autumn and winter seasons (MAM-JJA) compared to summer (DJF). In addition, all SREs were able to correctly identify no rain events, but during rainy days all SREs that did not use a local dataset of precipitation to recalibrate their estimates presented a low skill in providing an accurate classification of different precipitation intensities. Overall, MSWPEPv22 showed the best performance at all time scales and country-wide, due to the use of a Chilean dataset of daily data for calibrating its precipitation estimates, making it a good candidate for hydrological applications in Chile. Finally, we conclude that when the in situ precipitation dataset used in the evaluation of different SREs does not cover the headwaters of the catchments, the obtained performances should only be considered as first guess about how well a given SRE represent the real amount of water in an area. |
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| Megafires in Chile 2017: Monitoring multiscale environmental impacts of burned ecosystems | Science of The Total Environment | de la Barrera, F.; Barraza, F.; Favier, P.; Ruiz, V.; Quense, J. | 2018 | Ciudades Resilientes | 10.1016/j.scitotenv.2018.05.119 | http://linkinghub.elsevier.com/retrieve/pii/S0048969718317601 | 1526-1536 | Vol: 637-638 | 0048-9697 | Thomson Reuters ISI (SCIE) | English | During the summer of 2017, several megafires in South-Central Chile burned down forest plantations, native forests, shrublands and human settlements. National authorities identified the relevant effects of the wildfires on infrastructure and ecosystems. However, other indirect effects such as the risk of flooding or, increased air pollution were not assessed. The present study assesses: i) the geographic characterization of wildfires, ii) amount of damage to ecosystems and the severity of wildfires, iii) the effects of megafires on air quality in nearby and distant urban areas, and iv) identification of cities potentially exposed to landslides and flooding. We ran remote sensing analyses based on the Normalized Burn Ratio taken from Landsat imagery, “active fires” from MODIS, and ASTER GDEM. The particulate matter (PM10 and PM2.5) levels measured on 34 Chilean's municipalities were correlated with the burning area/distance ratio by Spearman correlation. Socionatural hazards were evaluated using multi-criteria analyses combining proximity to burned areas, severity, potential flow of water and sediments as indicated by the Digital Elevation Model, drainage networks and the location of human settlements. 91 burned areas were identified, covering 529,794 ha. The most affected ecosystems were forest plantations and native shrublands. We found significant correlations between burned area/distance ratios and PM2.5 and PM10 levels, leading to increased levels over the Chilean air quality standard in the most populated cities. 37 human settlements were at increased risk of landslides and flooding hazards after fires and eleven could now be characterized as dangerously exposed. The 2017 wildfires in Chile have had an impact at both a small and large scale, with far-reaching air pollutants dispersing and affecting >74% of the Chilean population. The impact of the wildfires was also extended over time, creating future potential for landslides and flooding, with the risk increasing in rainy seasons. | |
| ENSO Influence on Coastal Fog-Water Yield in the Atacama Desert, Chile | Aerosol and Air Quality Research | del Río, C.; Rivera, D.; Siegmund, A.; Wolf, N.; Cereceda, P.; Larraín, H.; Lobos, F.; Garcia, J.; Osses, P.; Zanetta, N.; Lambert, F. | 2018 | Ciudades Resilientes | 10.4209/aaqr.2017.01.0022 | http://www.aaqr.org/doi/10.4209/aaqr.2017.01.0022 | 127-144 | Vol: 18 Issue: 1 | 1680-8584 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Fog water represents an alternative, abundant and currently unexploited fresh water resource in the coastal Atacama Desert (~20°S). Here, the stratocumulus clouds meet the Coastal Cordillera, producing highly dynamic advective marine fog, a major feature of the local climate that provides water to a hyper-arid environment. One of the main issues that arises in harvesting fog water is our limited understanding of the spatial and inter-annual variability of fog clouds and their associated water content. Here we assess the role of regional-wide El Niño Southern Oscillation (ENSO) forcing on local inter-annual fog-water yields along the coast of Atacama. We contrast 17 years of continuous fog-water data, with local and regional atmospheric and oceanographic variables to determine the link between them and the inter-annual dynamics of fog in northern Chile. Sea surface temperature (SST) in ENSO zone 1 + 2 shows significant correlations with offshore and coastal Atacama SST, as well as with local low cloud cover and fog water yields, which go beyond the annual cycle beat, exposing a potential causal link and influence of ENSO on fog along the Atacama. On the inter-annual time scale, we found that when ENSO 3 + 4 zone SST, specifically during summer, overcome a > 1°C temperature threshold, they incite significantly higher summer fog water yields and explain 79% of the fog variability. Furthermore, satellite images displaying regional extent Sc cloud and fog presence during ENSO extremes reveal higher cloud abundance during El Niño at this latitude. However, 75% of the yearly fog water is collected during winter, and does not appear to be affected in a significant manner by Pacific oscillations. Thus, our results suggest that the utilization of fog as a fresh water resource may be sustainable in the future, regardless of ENSO-induced variability in the region. |
| Memoria institucional 2013 - 2017 | 2017 | Agua y Extremos; Cambio de Uso de Suelo; Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política; Zonas Costeras | https://www.cr2.cl/memoria-institucional-cr2-2013-2017/ | ||||||||||
| The First Millennium-Age Araucaria Araucana in Patagonia | Tree-Ring Research | Aguilera-Betti, I.; Muñoz, A.; Stahle, D.; Figueroa, G.; Duarte, F.; González-Reyes, Á.; Christie, D.; Lara, A.; González, M.; Sheppard, P.; Sauchyn, D.; Moreira-Muñoz, A.; Toledo-Guerrero, I.; Olea, M.; Apaz, P.; Fernandez, A. | 2017 | Dinámica del Clima; Servicios Ecosistémicos | 10.3959/1536-1098-73.1.53 | http://www.bioone.org/doi/10.3959/1536-1098-73.1.53 | 53-56 | Vol: 73 Issue: 1 | 1536-1098 | Thomson Reuters ISI (SCIE) | English | The iconic conifer Araucaria araucana (Araucaria), called Pehuén by native people, is an endemic species of the Andes of northern Patagonia in Chile and Argentina. Its range encompasses only three degrees of latitude (37 ◦ 20 – 40 ◦ 20 S) with a small outlying presence in the coastal mountains of Chile (Veblen et al. 1995). The species is classified as endangered (Premoli et al. 2013) because of extensive logging and human-set fires. Araucaria araucana has a long history of ethnobiological importance. For centuries the Pehuén fruits have been a vital sustainable food source for the Pehuenche people (Mapuche) and today the growing industry of ecotourism indirectly serves to protect these forests (Aagesen 1998; González et al. 2013). After a long history of human destruction of A. araucana forests, which reduced its range to half its original distribution, Chile and Argentina now legally protect this endangered species. These ecosystems continue to be threatened by logging, fires, and extensive livestock use. These factors, and the potential threats posed by climate change, are among the main challenges to A. araucana conservation (González and Lara 2015). |
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| Wind waves climatology of the Southeast Pacific Ocean | International Journal of Climatology | Aguirre, C.; Rutllant, J.; Falvey, M. | 2017 | Modelación y Sistemas de Observación | 10.1002/joc.5084 | http://onlinelibrary.wiley.com/doi/10.1002/joc.5084/abstract | 4288-4301 | Vol: 37 Issue: 9 | 0899-8418 | Thomson Reuters ISI (SCIE) | English | The climatology of wind waves over the Southeast Pacific is analysed using a 32-year hindcast from the WaveWatch III model, complemented by satellite-derived significant wave height (SWH) and buoy measurements for validation. Using partitioned spectral data, a regional climatology of wind sea and swell parameters was constructed. In general, the simulated SWH shows a good agreement with satellite and in situ SWH measurements, although the model appears to have a spatially uniform bias of approximately 0.3 m. The spatial pattern of SWH is clearly influenced by the meridional variation of mean surface wind speed, where the stronger winds over the Southern Ocean play a significant role generating higher waves at higher latitudes. Nevertheless, regional features are observed in the annual variability of SWH, which are associated with the existence of atmospheric coastal low-level jets off the coast of Peru and central Chile. In particular, the seasonal variation of these synoptic scale jets shows a direct relationship with the annual variability of SWH and with the probability of occurrence of wind sea conditions. Off the coast of Peru at approximately 15 ∘ S the coastal low-level jet is strongest during austral winter, increasing the wind sea SWH. In contrast, off central Chile, there is an important increase of wind sea SWH during summer. The seasonal variation of the wind sea component leads to a contrasting seasonal variation of the total SWH at these locations: off Peru the coastal jet amplifies the annual variability of SWH, while off Central Chile the annual variability of SWH is suppressed by the presence of the coastal jet. Although the general conclusions of this research are considered to be robust, we discuss the limitations of the spectral partitioning method used to distinguish wind sea and swell-sea states. | |
| Physiological and gene expression responses to nitrogen regimes and temperatures in Mastigocladus sp. strain CHP1, a predominant thermotolerant cyanobacterium of hot springs | Systematic and Applied Microbiology | Alcamán, M.; Alcorta, J.; Bergman, B.; Vásquez, M.; Polz, M.; Díez, B. | 2017 | Biogeoquímica | 10.1016/j.syapm.2016.11.007 | http://www.sciencedirect.com/science/article/pii/S0723202016301394 | 102-113 | Vol: 40 Issue: 2 | 0723-2020 | Thomson Reuters ISI (SCIE) | English | Cyanobacteria are widely distributed primary producers with significant implications for the global biogeochemical cycles of carbon and nitrogen. Diazotrophic cyanobacteria of subsection V (Order Stigonematales) are particularly ubiquitous in photoautotrophic microbial mats of hot springs. The Stigonematal cyanobacterium strain CHP1 isolated from the Porcelana hot spring (Chile) was one of the major contributors of the new nitrogen through nitrogen fixation. Further morphological and genetic characterization verified that the strain CHP1 belongs to Stigonematales, and it formed a separate clade together with other thermophiles of the genera Fischerella and Mastigocladus. Strain CHP1 fixed maximum N2 in the light, independent of the temperature range. At 50 °C nifH gene transcripts showed high expression during the light period, whereas the nifH gene expression at 45 °C was arrhythmic. The strain displayed a high affinity for nitrate and a low tolerance for high ammonium concentrations, whereas the narB and glnA genes showed higher expression in light and at the beginning of the dark phase. It is proposed that Mastigocladus sp. strain CHP1 would represent a good model for the study of subsection V thermophilic cyanobacteria, and for understanding the adaptations of these photoautotrophic organisms inhabiting microbial mats in hot springs globally. | |
| Local Perception of Drought Impacts in a Changing Climate: The Mega-Drought in Central Chile | Sustainability | Aldunce, P.; Araya, D.; Sapiain, R.; Ramos, I.; Lillo, G.; Urquiza, A.; Garreaud, R. | 2017 | Agua y Extremos; Gobernanza e Interfaz Ciencia y Política | 10.3390/su9112053 | http://www.mdpi.com/2071-1050/9/11/2053 | 2053 | Vol: 9 Issue: 12 | 2071-1050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Droughts are a recurrent and complex natural hazard whose frequency and magnitude are expected to increase with climate change. Despite the advances in responding and adapting to droughts (with the development of new policies, for example), droughts continue to cause serious impacts and suffering. Developing well-targeted public policies requires further research on adaptation. Specifically, understanding the public perception of drought can help to identify drivers of and barriers to adaptation and options. This research seeks to understand the public perception of drought in central Chile in order to inform adaptation-related policies and decision-making processes. This study focused on the Mega-drought, which was a protracted dry spell afflicting central Chile since 2010. |
| Surface ozone in the Southern Hemisphere: 20 years of data from a site with a unique setting in El Tololo, Chile | Atmos. Chem. Phys. | Anet, J.; Steinbacher, M.; Gallardo, L.; Velásquez Álvarez, P.; Emmenegger, L.; Buchmann, B. | 2017 | Modelación y Sistemas de Observación | 10.5194/acp-17-6477-2017 | http://www.atmos-chem-phys.net/17/6477/2017/ | 6477-6492 | Vol: 17 Issue: 10 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The knowledge of surface ozone mole fractions and their global distribution is of utmost importance due to the impact of ozone on human health and ecosystems and the central role of ozone in controlling the oxidation capacity of the troposphere. The availability of long-term ozone records is far better in the Northern than in the Southern Hemisphere, and recent analyses of the seven accessible records in the Southern Hemisphere have shown inconclusive trends. Since late 1995, surface ozone is measured in situ at "El Tololo", a high-altitude (2200 m a.s.l.) and pristine station in Chile (30° S, 71° W). The dataset has been recently fully quality controlled and reprocessed. This study presents the observed ozone trends and annual cycles and identifies key processes driving these patterns. From 1995 to 2010, an overall positive trend of ∼ 0.7 ppb decade−1 is found. Strongest trends per season are observed in March and April. Highest mole fractions are observed in late spring (October) and show a strong correlation with ozone transported from the stratosphere down into the troposphere, as simulated with a model. Over the 20 years of observations, the springtime ozone maximum has shifted to earlier times in the year, which, again, is strongly correlated with a temporal shift in the occurrence of the maximum of simulated stratospheric ozone transport at the site. We conclude that background ozone at El Tololo is mainly driven by stratospheric intrusions rather than photochemical production from anthropogenic and biogenic precursors. The major footprint of the sampled air masses is located over the Pacific Ocean. Therefore, due to the negligible influence of local processes, the ozone record also allows studying the influence of El Niño and La Niña episodes on background ozone levels in South America. In agreement with previous studies, we find that, during La Niña conditions, ozone mole fractions reach higher levels than during El Niño conditions. |
| Temporal evolution of main ambient PM2. 5 sources in Santiago, Chile, from 1998 to 2012 | Atmospheric Chemistry and Physics | Barraza, F.; Lambert, F.; Jorquera, H.; Villalobos, A.; Gallardo, L. | 2017 | Ciudades Resilientes | 10.5194/acp-17-10093-2017 | https://www.atmos-chem-phys.net/17/10093/2017/ | 10093-10107 | Vol: 17 Issue: 16 | 1680-7324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The inhabitants of Santiago, Chile have been exposed to harmful levels of air pollutants for decades. The city’s poor air quality is a result of steady economic growth, and stable atmospheric conditions adverse to mixing and ventilation that favor the formation of oxidants and secondary aerosols. Identifying and quantifying the sources that contribute to the ambient levels of pollutants is key for designing adequate mitigation measures. Estimating the evolution of source contributions to ambient pollution levels is also paramount to evaluating the effectiveness of pollution reduction measures that have been implemented in recent decades. Here, we quantify the main sources that have contributed to fine particulate matter (PM2.5) between April 1998 and August 2012 in downtown Santiago by using two different source-receptor models (PMF 5.0 and UNMIX 6.0) that were applied to elemental measurements of 1243 24 h filter samples of ambient PM2.5. PMF resolved six sources that contributed to ambient PM2.5, with UNMIX producing similar results: motor vehicles (37.3 ± 1.1 %), industrial sources (18.5 ± 1.3 %), copper smelters (14.4 ± 0.8 %), wood burning (12.3 ± 1.0 %), coastal sources (9.5 ± 0.7 %) and urban dust (3.0 ± 1.2 %). Our results show that over the 15 years analyzed here, four of the resolved sources significantly decreased 95 % confidence interval: motor vehicles 21.3 % 2.6, 36.5, industrial sources 39.3 % 28.6, 48.4, copper smelters 81.5 % 75.5, 85.9, and coastal sources 58.9 % 38.5, 72.5, while wood burning did not significantly change and urban dust increased by 72 % 48.9, 99.9. These changes are consistent with emission reduction measures, such as improved vehicle emission standards, cleaner smelting technology, introduction of low-sulfur diesel for vehicles and natural gas for industrial processes, public transport improvements, etc. However, it is also apparent that the mitigation expected from the above regulations has been partially offset by the increasing amount of private vehicle use in the city, with motor vehicles becoming the dominant source of ambient PM2.5 in recent years. Consequently, Santiago still experiences ambient PM2.5 levels above the annual and 24 h Chilean and World Health Organization standards, and further regulations are required to reach ambient air quality standards |
| Accelerated greenhouse gases versus slow insolation forcing induced climate changes in southern South America since the Mid-Holocene | Climate Dynamics | Berman, A.; Silvestri, G.; Rojas, M.; Tonello, M. | 2017 | Modelación y Sistemas de Observación | 10.1007/s00382-016-3081-z | http://link.springer.com/10.1007/s00382-016-3081-z | 387-404 | Vol: 48 Issue: 1-2 | 0930-7575, 1432-0894 | Thomson Reuters ISI (SCIE) | English | This paper is a pioneering analysis of past climates in southern South America combining multiproxy reconstructions and the state-of-the-art CMIP5/PMIP3 paleoclimatic models to investigate the time evolution of regional climatic conditions from the Mid-Holocene (MH) to the present. This analysis allows a comparison between the impact of the long term climate variations associated with insolation changes and the more recent effects of anthropogenic forcing on the region. The PMIP3 multimodel experiments suggest that changes in precipitation over almost all southern South America between MH and pre-industrial (PI) times due to insolation variations are significantly larger than those between PI and the present, which are due to changes in greenhouse gas concentrations. Anthropogenic forcing has been particularly intense over western Patagonia inducing reduction of precipitation in summer, autumn and winter as a consequence of progressively weaker westerly winds over the region, which have moved further poleward, between ca. 35–55°S and have become stronger south of about 50°S. Orbital variations between the MH to the PI period increased insolation over southern South America during summer and autumn inducing warmer conditions in the PI, accentuated by the effect of anthropogenic forcing during the last century. On the other hand, changes in orbital parameters from the MH to the PI period reduced insolation during winter and spring inducing colder conditions, which have been reversed by the anthropogenic forcing. © 2016, Springer-Verlag Berlin Heidelberg. | |
| Ecosystem services and local wellbeing: Case study on natural medicine products in Panguipulli, Southern Chile; [Servicios ecosistémicos y bienestar local: Caso de estudio sobre productos de medicina natural en Panguipulli, sur de Chile] | Ecologia Austral | Betancourt Arellano, R.; Nahuelhual Muñoz, L. | 2017 | Dimensión Humana | 10.25260/EA.17.27.1.1.269 | https://doi.org/10.25260/EA.17.27.1.1.269 | 99-112 | Vol: 27 Issue: 1 | 0327-5477, 1667-782X | Scopus | Spanish | El presente estudio explora cómo se construye bienestar en comunidades locales del sur de Chile a través de prácticas sociales relacionadas con el uso de productos de medicina natural local (PMNL). Para la investigación se reconstruyeron historias de vida de actores sociales relevantes, por medio de entrevistas en profundidad. El análisis se basó en las teorías de la acción social y del desarrollo a escala humana, y sobre el enfoque de servicios ecosistémicos. Los resultados indican que en este territorio, el bienestar se construye socialmente a través de prácticas cotidianas dentro de la unidad familiar, en un ambiente mucho más privado (e.g., la transmisión de conocimiento entre padres e hijos al recolectar y reconocer plantas medicinales y su aplicación). Además, los actores sociales también construyen bienestar con prácticas comunitarias públicas, como es el caso de la mayoría de las iniciativas de recolección y procesamiento del Programa de Salud Inter-Cultural, que reponen el stock de medicinas. Por su parte, la teoría de la acción permitió observar prácticas sociales desde la vida cotidiana, mientras que el enfoque de servicios ecosistémicos ayudó a observar y a comprender los recursos naturales relacionados con estrategias de satisfacción local. Por esta razón, se convirtió en un anclaje teórico para comprender el bienestar desde la perspectiva del desarrollo humano. En este sentido, los principales satisfactores identificados fueron el Programa de Salud Inter-Cultural, la Mesa de Salud Inter-Cultural y los agentes culturales y unidad familiar. El Programa de Salud Inter-Cultural se relacionó de manera sinérgica con varias necesidades, mientras que la Mesa de Salud Inter-Cultural sólo se relacionó con las necesidades de entendimiento y participación. Finalmente, los agentes culturales y la unidad familiar se relacionaron con necesidades de afecto, ocio y libertad, entre otras. | |
| Comunicación ambiental y proyectos energéticos renovables no convencionales. Análisis de contenido en medios de comunicación de masa chilenos | Revista Latina de Comunicación Social | Billi, M.; Urquiza Gómez, A.; Feres Klenner, C. | 2017 | Ciudades Resilientes | 10.4185/RLCS-2017-1216 | http://www.revistalatinacs.org/072paper/1216/66es.html | 1218-1237 | Vol: 72 | 1138-5820 | Thomson Reuters ISI (ESCI) | All Open Access; Bronze Open Access | Spanish | ntroduction. We observe how mass media thematise Non-Conventional Renewable Energy projects [NCRE] in terms of relevance and treatment assigned to distinct sources and emerging thematic structures. Methodology. Mixed-approach content analysis of a sample of 100 Chilean digital press articles relating to NCRE, using the analytical framework of Niklas Luhmann’s Social Systems Theory. Results and Discussion. The predominance of solar and wind sources goes hand in hand with a low terminological clarity, which however allows mass media to build distinct thematic structures around social systems such as economy, science, politics and law. Environmental references are less frequent and shallower, privileging its evocative aspects with maximum linkage capacity. Conclusions. Instead than observing mass media as mere transmitters of rationalities external to them, more attention should be given to their ability to create realities and representing the (human and ecological) environment. |
| LA EXTRACCIÓN PREHISPÁNICA DE RECURSOS MINERALES EN EL INTERNODO QUILLAGUA-COSTA, DESIERTO DE ATACAMA | Estudios atacameños | Blanco, J.; Correa G, I.; Flores, C.; Pimentel G, G. | 2017 | Biogeoquímica | 10.4067/S0718-10432017005000003 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-10432017005000003&lng=en&nrm=iso&tlng=en | 77-102 | Vol: 56 | 0718-1043 | Thomson Reuters ISI (ESCI) | All Open Access; Hybrid Gold Open Access | Spanish | Internodal archaeological evidence of extractive occupations is presented in this study. Evidence comes from the survey and analyses of sites on the prehistoric route between Quillagua (inferior Loa River) and the north Coast of Tocopilla, across the Coastal mountain range of the Atacama Desert. This archaeological record is discussed in relation to previouslyknown prehistoric data about settlements and internodal trails of the Coast, and Inferior and middle Loa sections. We characterize two extractive sites of mineral resources detected in association to pathways, a mine and a lithic workshop. Data from excavations, analyses of archaeological materials and absolute dates are used to discuss mobility of coastal groups to the interior of the desert and of Oasis's societies to the coast in different periods of time. Previously formulated models of mobility and provisioning, as well as regional archaeological and ethnographic data, are used to discuss the presented results, and are applied to examine more general aspects of "Internodal Studies". |
| Resilience to climate change: from theory to practice through co-production of knowledge in Chile | Sustainability Science | Borquez, R.; Aldunce, P.; Adler, C. | 2017 | Dimensión Humana | 10.1007/s11625-016-0400-6 | http://link.springer.com/article/10.1007/s11625-016-0400-6 | 163-176 | Vol: 12 Issue: 1 | 1862-4065 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access; Hybrid Gold Open Access | English | In theory, building resilience is touted as one way to deal with climate change impacts; however, in practice, there is a need to examine how contexts influence the capacity of building resilience. A participatory process was carried out through workshops in regions affected by drought in Chile in 2014. The aim was to explore how resilience theory can be better applied and articulated into practice vis-á-vis participatory approaches that enrich the research process through the incorporation of co-produced. The results show that there are more differences in responses by type of actor than between regions, where issues of national interest, such as ‘education-information’ and ‘preparedness’, are highlighted over others. However, historically relevant local topics emerged as differentiators: decentralisation, and political will. This reinforces why special attention must be given to the different understandings in knowledge co-production processes. This study provides evidence and lessons on the importance of incorporating processes of the co-production of knowledge as a means to better articulate and transfer abstract concepts, such as resilience theory, into practice. |
| Interfaz ciencia-políticas públicas en Chile: una mirada a la investigación en cambio climático | Revista Colombiana de Sociología | Borquéz González, R. | 2017 | Gobernanza e Interfaz Ciencia y Política | 10.15446/rcs.v40n2.66402 | https://revistas.unal.edu.co/index.php/recs/article/view/66402 | 311-332 | Vol: 40 Issue: 2 | 2256-5485, 0120-159X | Thomson Reuters ISI (ESCI) | Spanish | Important changes in the relation between science and society have taken place in the last few decades. There has been a shift from a paradigm in which science transforms society to one that opens up the possibility of society transforming science. The contribution of the science sector, as well as that of each one of the social actors, is fundamental in supporting decision-making regarding public policies, as stated by the Intergovernmental Panel on Climate Change (IPCC), which has played a key role in the adoption of actions by the international community. In Chile, however, the relation between science and politics has not been smooth enough. On the basis of an exploratory qualitative methodology, the objective of our study was to identify and analyze the gaps and facilitators of the relation between researchers in the field of natural science and public policies in Chile, focusing on the area of climate change. This made it possible to analyze the structure and dynamics of incentives for activities in the scientific and public spheres, as well as the existing mechanisms for communication and coordination between them. Thus, eight gaps and two facilitators were identified. The following aspects are worth highlighting: the scarce interest of the science sector in providing advisories requested by the public services that generate public policies; the lack of incentives or academic demands to simplify contents; and the absence of regular communication and interaction, which creates a difference between what the political-administrative sphere expects of scientists and the way the latter think their participation can be useful and effective. Moreover, flaws in the coordination between those who finance research and those who design public policies were observed. The results also show that the gaps between spheres are not limited to the issue of climate change; rather, they are due to the way scientific and political structures are shaped in Chile. | |
| Which seed origin provides better tolerance to flooding and drought when restoring to face climate change? | Austral Ecology | Bustos-Salazar, A.; Smith-Ramírez, C.; Zúñiga-Feest, A.; Alves, F.; Ivanovich, R. | 2017 | Cambio de Uso de Suelo | 10.1111/aec.12521 | https://doi.org/10.1111/aec.12521 | 934-946 | Vol: 42 Issue: 8 | 1442-9985 | Thomson Reuters ISI (SCIE) | English | Our goal was to establish the tolerance to flooding and drought of seedlings from a hydric gradient of different seed sources to provide recommendations for forest restoration in the face of climate change. We used Drimys winteri var. chilensis, a tree species that grows from extreme arid zones to wetlands along Chile, as the study subject. We expected that seedlings of xeric origin would perform better in drought conditions than populations from moist environments, and vice versa for flooding tolerance. We collected D. winteri seeds from xeric, mesic and wet environments. Seedlings at two development stages were submitted to an extreme flooding and drought treatment during 2 or 4 months in a common garden. After the flooding and drought assays finished, the number of surviving and damaged seedlings, lenticels and adventitious root presence, height, new leaves and specific leaf area, shoot/root ratio, water potential and/or chlorophyll fluorescence (Fv/Fm), were recorded. We found that flooding and drought affected almost all the parameters studied negatively. The xeric population seedlings, at both development stages studied, were the most tolerant to the drought and, unexpectedly, also to the flooding treatment. We recommend restoring with seedlings of xeric origin especially in arid areas where sudden flooding is frequent, as occurs in the Andes Mountains. In the face of climate change, we recommend carrying out common garden and field studies before advising which population origin should be used for restoration, since they do not always respond in accordance with expected patterns of local adaptation. © 2017 Ecological Society of Australia | |
| On the Nitrous Oxide Accumulation in Intermediate Waters of the Eastern South Pacific Ocean | Frontiers in Marine Science | Carrasco, C.; Karstensen, J.; Farías, L. | 2017 | Biogeoquímica | 10.3389/fmars.2017.00024 | http://journal.frontiersin.org/article/10.3389/fmars.2017.00024/full | art24 | Vol: 4 | 2296-7745 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Nitrous oxide (N2O) is a powerful greenhouse gas principally produced by nitrification and denitrification in the marine environment. Observations were made in the eastern South Pacific (ESP), between 10° and 60°S, and ~75°–88°W, from intermediate waters targeting Antarctic Intermediate Water (AAIW) at potential density of 27.0–27.1 kg m−3. Between 60° and 20°S, a gradual equatorward increase of N2O from 8 to 26 nmol L−1 was observed at density 27.0–27.1 kg m−3 where AAIW penetrates. Positive correlations were found between apparent N2O production (ΔN2O) and O2 utilization (AOU), and between ΔN2O and NO−3NO3−, which suggested that local N2O production is predominantly produced by nitrification. Closer to the equator, between 20° and 10°S at AAIW core, a strong N2O increase up to 75 nmol L−1 was observed. Because negative correlations were found between ΔN2O vs. NO−3NO3− and ΔN2O vs. N* (a Nitrogen deficit index) and because ΔN2O and AOU do not follow a linear trend, we suspect that, in addition to nitrification, denitrification also takes place in N2O cycling. By making use of water mass mixing analyses, we show that an increase in N2O occurs in the region where high oxygen from AAIW merges with low oxygen from Equatorial Subsurface Water (ESSW), creating favorable conditions for local N2O production. We conclude that the non-linearity in the relationship between N2O and O2 is a result of mixing between two water masses with very different source characteristics, paired with the different time frames of nitrification and denitrification processes that impact water masses en route before they finally meet and mix in the ESP region. |
| Predicting Vascular Plant Diversity in Anthropogenic Peatlands: Comparison of Modeling Methods with Free Satellite Data | Remote Sensing | Castillo-Riffart, I.; Galleguillos, M.; Lopatin, J.; Perez-Quezada, J. | 2017 | Cambio de Uso de Suelo | 10.3390/rs9070681 | http://www.mdpi.com/2072-4292/9/7/681 | 681 | Vol: 9 Issue: 7 | 2072-4292 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Peatlands are ecosystems of great relevance, because they have an important number of ecological functions that provide many services to mankind. However, studies focusing on plant diversity, addressed from the remote sensing perspective, are still scarce in these environments. In the present study, predictions of vascular plant richness and diversity were performed in three anthropogenic peatlands on Chiloé Island, Chile, using free satellite data from the sensors OLI, ASTER, and MSI. Also, we compared the suitability of these sensors using two modeling methods: random forest (RF) and the generalized linear model (GLM). As predictors for the empirical models, we used the spectral bands, vegetation indices and textural metrics. Variable importance was estimated using recursive feature elimination (RFE). Fourteen out of the 17 predictors chosen by RFE were textural metrics, demonstrating the importance of the spatial context to predict species richness and diversity. Non-significant differences were found between the algorithms; however, the GLM models often showed slightly better results than the RF. Predictions obtained by the different satellite sensors did not show significant differences; nevertheless, the best models were obtained with ASTER (richness: R2 = 0.62 and %RMSE = 17.2, diversity: R2 = 0.71 and %RMSE = 20.2, obtained with RF and GLM respectively), followed by OLI and MSI. Diversity obtained higher accuracies than richness; nonetheless, accurate predictions were achieved for both, demonstrating the potential of free satellite data for the prediction of relevant community characteristics in anthropogenic peatland ecosystems. © 2017 by the authors. |
| Modeling study of biomass burning plumes and their impact on urban air quality; a case study of Santiago de Chile | Atmospheric Environment | Cuchiara, G.; Rappenglück, B.; Rubio, M.; Lissi, E.; Gramsch, E.; Garreaud, R. | 2017 | Agua y Extremos | 10.1016/j.atmosenv.2017.07.002 | http://linkinghub.elsevier.com/retrieve/pii/S1352231017304430 | 79-91 | Vol: 166 | 13522310 | Thomson Reuters ISI (SCIE) | English | On January 4, 2014, during the summer period in South America, an intense forest and dry pasture wildfire occurred nearby the city of Santiago de Chile. On that day the biomass-burning plume was transported by low-intensity winds towards the metropolitan area of Santiago and impacted the concentration of pollutants in this region. In this study, the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem) is implemented to investigate the biomass-burning plume associated with these wildfires nearby Santiago, which impacted the ground-level ozone concentration and exacerbated Santiago's air quality. Meteorological variables simulated by WRF/Chem are compared against surface and radiosonde observations, and the results show that the model reproduces fairly well the observed wind speed, wind direction air temperature and relative humidity for the case studied. Based on an analysis of the transport of an inert tracer released over the locations, and at the time the wildfires were captured by the satellite-borne Moderate Resolution Imaging Spectroradiometer (MODIS), the model reproduced reasonably well the transport of biomass burning plume towards the city of Santiago de Chile within a time delay of two hours as observed in ceilometer data. A six day air quality simulation was performed: the first three days were used to validate the anthropogenic and biogenic emissions, and the last three days (during and after the wildfire event) to analyze the performance of WRF/Chem plume-rise model within FINNv1 fire emission estimations. The model presented a satisfactory performance on the first days of the simulation when contrasted against data from the well-established air quality network over the city of Santiago de Chile. These days represent the urban air quality base case for Santiago de Chile unimpacted by fire emissions. However, for the last three simulation days, which were impacted by the fire emissions, the statistical indices showed a decrease in the model performance. While the model showed a satisfactory evidence that wildfires plumes that originated in the vicinity of Santiago de Chile were transported towards the urban area and impacted the air quality, the model still underpredicted some pollutants substantially, likely due to misrepresentation of fire emission sources during those days. Potential uncertainties may include to the land use/land cover classifications and its characteristics, such as type and density of vegetation assigned to the region, where the fire spots are detected. The variability of the ecosystem type during the fire event might also play a role. | |
| Impact of the choice of the satellite aerosol optical depth product in a sub-regional dust emission inversion | Atmospheric Chemistry and Physics | Escribano, J.; Boucher, O.; Chevallier, F.; Huneeus, N. | 2017 | Modelación y Sistemas de Observación | 10.5194/acp-17-7111-2017 | http://www.atmos-chem-phys.net/17/7111/2017/ | 1-22 | Vol: 17 Issue: 11 | 1680-7316 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Mineral dust is the major continental contributor to the global atmospheric aerosol burden with important effects on the climate system. Regionally, a large fraction of the emitted dust is produced in North Africa, however the total emission flux from this region is still highly uncertain. In order to reduce these uncertainties, emission estimates through top-down approaches (i.e., usually models constrained by observations) had been successfully developed and implemented. Such studies usually rely on a single observational dataset and propagate the possible observational errors of this dataset onto the emission estimates. In this study, aerosol optical depth (AOD) products from five different satellites are assimilated one by one in a source inversion system to estimate dust emission fluxes over northern Africa and the Arabian Peninsula. We estimate mineral dust emissions for the year 2006 and discuss the impact of the assimilated dataset on the analysis. We find a relatively large dispersion in flux estimates among the five experiments, which can likely be attributed to differences in the assimilated observation datasets and their associated error statistics. We also show how the assimilation of a variety of AOD products can help to identify systematic errors in models. |
| Dissolved methane distribution in the Reloncavi fjord and adjacent marine system during austral winter (41º-43ºS) | Estuaries and Coasts | Farías, L.; Sanzana, K.; Sanhueza-Guevara, S.; Yevenes, M. | 2017 | Biogeoquímica | 10.1007/s12237-017-0241-2 | http://link.springer.com/article/10.1007/s12237-017-0241-2 | 1592–1606 | Vol: 40 | 1559-2723 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Within the earth’s atmosphere, methane (CH4) is one of the most important absorbers of infrared energy. It is recognized that coastal areas contribute higher amounts of CH4 emission; however, there is a lack of accurate estimates for these areas. This is particularly evident within the extensive northern fjord region of Chilean Patagonia, which has one of the highest freshwater runoffs in the world. Oceanographic and biogeochemical variables were analyzed between the Reloncaví fjord (41° S) and the Interior Sea of Chiloé (ISC) (43° S), during the 2013 austral winter. Freshwater runoff into the fjord influences salinity distribution, which clearly delimits the surface (<5 m depth) and subsurface layers (>5 m depth), and also separates the estuarine area from the marine area. In the estuary, the highest CH4 levels are generally observed in the cold and brackish nutrient-depleted surface waters (N- and P-depleted), ranging from 16.97 to 151.4 nM (mean ± SD 52.20 ± 46.49), equivalent to 640–4537% saturation except for the case of Si(OH)4. Conversely, subsurface waters have lower CH4 levels, fluctuating from 14.3 to 29.6 nM (mean ± SD 22.75 ± 4.36 nM) or 552–1087% saturation. A significant negative correlation was observed between salinity and CH4, and a positive correlation between Si(OH)4 and CH4, suggesting that some of the CH4 in estuarine water is due to continental runoff. Furthermore, the accumulation of seston and/or plankton at the pycnocline may potentially generate the accumulation of CH4 via microbial processes, as observed in estuarine waters. By contrast, the marine area (the ISC), which is predominantly made up of modified subantarctic water, has a relatively homogenous CH4 distribution (mean ± SD 9.84 ± 6.20 nM). In comparison with other estuaries, the Reloncaví fjord is a moderate source of CH4 to the atmosphere, with effluxes ranging from 23.9 to 136 μmol m−2 day−1. This is almost double the levels observed in the ISC, which ranges from 22.2 to 46.6 μmol m−2 day−1. Considering that Chilean Patagonia has numerous other fjord systems that are geomorphologically alike, and in some cases have much greater freshwater discharge, this study highlights their potential to be a significant natural source of this greenhouse gas. |
| Estimation of actual evapotranspiration over a rainfed vineyard using a 1-D water transfer model: A case study within a Mediterranean watershed | Agricultural Water Management | Galleguillos, M.; Jacob, F.; Prévot, L.; Faúndez, C.; Bsaibes, A. | 2017 | Servicios Ecosistémicos | 10.1016/j.agwat.2017.01.006 | http://www.sciencedirect.com/science/article/pii/S037837741730015X?np=y | 67-76 | Vol: 184 | 0378-3774 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The current study aims to evaluate the capabilities of soil water balance modeling to estimate ET for very different conditions of rainfed grapevine water status, within a vineyard landscape that depicts heterogeneities in canopy, soil and water table conditions. We calibrated the HYDRUS-1D model against measurements of the soil moisture profile within seven contrasted sites, we validated HYDRUS-1D simulations against ET estimates derived from eddy covariance (EC) measurements within two contrasted sites, and we analyzed the temporal dynamics of the HYDRUS-1D ET simulations throughout almost two growth cycles for the seven sites. The calibration of HYDRUS-1D was correctly achieved, with a relative RMSE of 20% on average. Validation of HYDRUS-1D simulations against EC measurements was satisfactory, with RMSE values of about 40 W m−2 at the hourly timescale and 0.5 mm d−1 at the daily timescale. HYDRUS-1D was able to provide consistent time series of ET within the seven contrasted sites and throughout the two growth cycles. We conclude that HYDRUS-1D simulations can be used as an alternative to EC measurements within rainfed vineyards, to alleviate experimental efforts for device cost and maintenance. Further, HYDRUS-1D simulations can be used for characterizing spatial variabilities and temporal dynamics, assessing impact of pedological conditions and land use on ET, or validating remote sensing retrievals over regional extents. |
| Vertical segregation among pathways mediating nitrogen loss (N2 and N2O production) across the oxygen gradient in a coastal upwelling ecosystem | Biogeosciences | Galán, A.; Thamdrup, B.; Saldías, G.; Farías, L. | 2017 | Zonas Costeras | 10.5194/bg-14-4795-2017 | https://www.biogeosciences.net/14/4795/2017/ | 4795-4813 | Vol: 14 Issue: 20 | 1726-4189 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The upwelling system off central Chile (36.5 S) is seasonally subjected to oxygen (O2)-deficient waters, with a strong vertical gradient in O2 (from oxic to anoxic conditions) that spans a few metres (30-50€m interval) over the shelf. This condition inhibits and/or stimulates processes involved in nitrogen (N) removal (e.g. anammox, denitrification, and nitrification). During austral spring (September 2013) and summer (January 2014), the main pathways involved in N loss and its speciation, in the form of N2 and/or N2O, were studied using 15N-tracer incubations, inhibitor assays, and the natural abundance of nitrate isotopes along with hydrographic information. Incubations were developed using water retrieved from the oxycline (25€m depth) and bottom waters (85€m depth) over the continental shelf off Concepción, Chile. Results of 15N-labelled incubations revealed higher N removal activity during the austral summer, with denitrification as the dominant N2-producing pathway, which occurred together with anammox at all times. Interestingly, in both spring and summer maximum potential N removal rates were observed in the oxycline, where a greater availability of oxygen was observed (maximum O2 fluctuation between 270 and 40€μmol€L'1) relative to the hypoxic bottom waters ( < €20€μmol€O2€L'1). Different pathways were responsible for N2O produced in the oxycline and bottom waters, with ammonium oxidation and dissimilatory nitrite reduction, respectively, as the main source processes. Ammonium produced by dissimilatory nitrite reduction to ammonium (DNiRA) could sustain both anammox and nitrification rates, including the ammonium utilized for N2O production. The temporal and vertical variability of /15N-NO3' confirms that multiple N-cycling processes are modulating the isotopic nitrate composition over the shelf off central Chile during spring and summer. N removal processes in this coastal system appear to be related to the availability and distribution of oxygen and particles, which are a source of organic matter and the fuel for the production of other electron donors (i.e. ammonium) and acceptors (i.e. nitrate and nitrite) after its remineralization. These results highlight the links between several pathways involved in N loss. They also establish that different mechanisms supported by alternative N substrates are responsible for substantial accumulation of N2O, which are frequently observed as hotspots in the oxycline and bottom waters. Considering the extreme variation in oxygen observed in several coastal upwelling systems, these findings could help to understand the ecological and biogeochemical implications due to global warming where intensification and/or expansion of the oceanic OMZs is projected. |
| The 2010-2015 mega drought in Central Chile: Impacts on regional hydroclimate and vegetation | Hydrology and Earth System Sciences | Garreaud, R.; Alvarez-Garreton, C.; Barichivich, J.; Boisier, J.; Christie, D.; Galleguillos, M.; LeQuesne, C.; McPhee, J.; Zambrano-Bigiarini, M. | 2017 | Agua y Extremos; Cambio de Uso de Suelo | 10.5194/hess-21-6307-2017 | https://www.hydrol-earth-syst-sci-discuss.net/hess-2017-191/ | 6307-6327 | Vol: 21 Issue: 12 | 1027-5606 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Since 2010 an uninterrupted sequence of dry years, with annual rainfall deficits ranging from 25 to 45 %, has prevailed in Central Chile (western South America, 30–38° S). Although intense 1- or 2-year droughts are recurrent in this Mediterranean-like region, the ongoing event stands out because of its longevity and large spatial extent. The extraordinary character of the so-called Central Chile Mega Drought (MD) was established against century long historical records and a millennial tree-ring reconstruction of regional precipitation. The largest MD-averaged rainfall relative anomalies occurred in the northern, semi-arid sector of central Chile but the event was unprecedented to the south of 35° S. ENSO neutral conditions have prevailed since 2011 (but for the strong El Niño 2015) contrasting with La Niña conditions that often accompanied past droughts. The precipitation deficit diminished the Andean snowpack and resulted in amplified declines (up to 90 %) of river flow, reservoir volumes and groundwater levels along central Chile and westernmost Argentina. In some semiarid basins we also found a conspicuous decrease in the runoff-to-rainfall coefficient. A substantial decrease in vegetation productivity occurred in the shrubland-dominated, northern sector, but a mix of greening and browning patches occurred farther south where irrigated croplands and exotic forest plantations dominate. The ongoing warming in central Chile, making the MD one of the warmest 6-year period on record, may have also contributed to such complex vegetation changes by increasing potential evapotranspiration. The understanding of the nature and biophysical impacts of the MD contributes to preparedness efforts to face a dry, warm future regional climate scenario. |
| Spatio-temporal variations in hydroclimate across the Mediterranean Andes (30°-37°S) since the early 20th century | Journal of Hydrometeorology | González–Reyes, Á.; McPhee, J.; Christie, D.; Le Quesne, C.; Szejner, P.; Masiokas, M.; Villalba, R.; Muñoz, A.; Crespo, S. | 2017 | Dinámica del Clima; Servicios Ecosistémicos | 10.1175/JHM-D-16-0004.1 | http://journals.ametsoc.org/doi/10.1175/JHM-D-16-0004.1 | 1929-1942 | Vol: 18 Issue: 7 | 1525-755X | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | In the Mediterranean Andes (MA; 30°S–37°S), the main rivers are largely fed by melting snowpack and provide fresh water to around 10 million people on both sides of the Cordillera. Water resources in the MA are under pressure due to the extensive development of industrial agriculture and mining activities. This pressure is increasing as the region faces one of its worst recorded droughts. Previous studies have pointed to the El Niño Southern Oscillation (ENSO) as the main climatic force impacting the MA. However, the role of decadal and multidecadal climate variability, their spatial patterns and the recurrence of long-term droughts, remains poorly studied. In this contribution to a better understanding of these factors, spatial and temporal patterns of hydroclimatic variability are analyzed using an extensive database of streamflow, precipitation, and snowpack covering the period between 1910 – 2011. These analyses are based on the combination of correlation, principal components and kernel-estimation techniques. Despite a general common pattern across the MA region, our results identify two hydroclimatic sub-regions, located north and south of 34°S. While the interannual variability associated with ENSO is slightly stronger north of 34°S, the variability associated with the Pacific Decadal Oscillation (PDO) and/or the Inter-decadal Pacific Oscillation index (IPO) shows similar patterns in both regions. However, variations produced by the IPO forcing seem to be greater in the southern sub-region since 1975. Our estimations on drought recurrence reveal a generalized increase in dry extremes since the 1950’s. These findings suggest that the northern MA are more vulnerable to changes in hydrology and climate than the southern MA. |
| Impacts of future deforestation and climate change on the hydrology of the Amazon Basin: a multi-model analysis with a new set of land-cover change scenarios | Hydrology and Earth System Sciences | Guimberteau, M.; Ciais, P.; Ducharne, A.; Boisier, J.; Dutra Aguiar, A.; Biemans, H.; De Deurwaerder, H.; Galbraith, D.; Kruijt, B.; Langerwisch, F.; Poveda, G.; Rammig, A.; Rodriguez, D.; Tejada, G.; Thonicke, K.; Von Randow, C.; Von Randow, R.; Zhang, K.; Verbeeck, H. | 2017 | Dinámica del Clima | 10.5194/hess-21-1455-2017 | https://www.hydrol-earth-syst-sci.net/21/1455/2017/ | 1455-1475 | Vol: 21 Issue: 3 | 1607-7938 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Deforestation in Amazon is expected to decrease evapotranspiration (ET) and to increase soil moisture and river discharge under prevailing energy-limited conditions. The magnitude and sign of the response of ET to deforestation depend both on the magnitude and regional patterns of land-cover change (LCC), as well as on climate change and CO2 levels. On the one hand, elevated CO2 decreases leaf-scale transpiration, but this effect could be offset by increased foliar area density. Using three regional LCC scenarios specifically established for the Brazilian and Bolivian Amazon, we investigate the impacts of climate change and deforestation on the surface hydrology of the Amazon Basin for this century, taking 2009 as a reference. For each LCC scenario, three land surface models (LSMs), LPJmL-DGVM, INLAND-DGVM and ORCHIDEE, are forced by bias-corrected climate simulated by three general circulation models (GCMs) of the IPCC 4th Assessment Report (AR4). On average, over the Amazon Basin with no deforestation, the GCM results indicate a temperature increase of 3.3 °C by 2100 which drives up the evaporative demand, whereby precipitation increases by 8.5 %, with a large uncertainty across GCMs. In the case of no deforestation, we found that ET and runoff increase by 5.0 and 14 %, respectively. However, in south-east Amazonia, precipitation decreases by 10 % at the end of the dry season and the three LSMs produce a 6 % decrease of ET, which is less than precipitation, so that runoff decreases by 22 %. For instance, the minimum river discharge of the Rio Tapajós is reduced by 31 % in 2100. To study the additional effect of deforestation, we prescribed to the LSMs three contrasted LCC scenarios, with a forest decline going from 7 to 34 % over this century. All three scenarios partly offset the climate-induced increase of ET, and runoff increases over the entire Amazon. In the south-east, however, deforestation amplifies the decrease of ET at the end of dry season, leading to a large increase of runoff (up to +27 % in the extreme deforestation case), offsetting the negative effect of climate change, thus balancing the decrease of low flows in the Rio Tapajós. These projections are associated with large uncertainties, which we attribute separately to the differences in LSMs, GCMs and to the uncertain range of deforestation. At the subcatchment scale, the uncertainty range on ET changes is shown to first depend on GCMs, while the uncertainty of runoff projections is predominantly induced by LSM structural differences. By contrast, we found that the uncertainty in both ET and runoff changes attributable to uncertain future deforestation is low. |
| Postfire responses of the woody flora of Central Chile: Insights from a germination experiment | PLOS ONE | Gómez-González, S.; Paula, S.; Cavieres, L.; Pausas, J. | 2017 | Cambio de Uso de Suelo | 10.1371/journal.pone.0180661 | http://dx.plos.org/10.1371/journal.pone.0180661 | e0180661 | Vol: 12 Issue: 7 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Fire is a selective agent shaping plant traits and community assembly in fire-prone ecosystems. However, in ecosystems with no fire history, it can be a cause of land degradation when it is suddenly introduced by humans, as plant species may not be able to respond to such novel disturbance. Unlike other Mediterranean-type ecosystems (MTE) of the world, natural fires have not been frequent during the Quaternary in the matorral of Central Chile, and thus, plant adaptive responses are expected to be uncommon. We evaluated the effect of heat shock on seed survival and germination of 21 native woody plants of the Chilean matorral and compiled information on smoke-stimulation and resprouting, to evaluate the importance of fire-adaptive responses in the context of the other MTE. We found that in the Chilean woody flora negative seed responses to fire cues were more frequent than positive responses. Although resprouting is a relatively widespread trait, fire-stimulated germination is not as common in the Chilean matorral as in other MTE. The seeds of seven endemic species were strongly damaged by fire cues and this should be considered in post-fire restoration planning. However, our results also showed that many species were resistant to elevated doses of heat shock and in some, germination was even stimulated. Thus, future research should focus on the evolutionary causes of these responses. These findings could help to develop strategies for fire management in the Chilean matorral. In addition, they will improve our understanding of the evolutionary forces that shaped this plant community and to better frame this region among the other MTE worldwide. |
| Plankton composition, biomass, phylogeny and toxin genes in Lake Big Momela, Tanzania | African Journal of Aquatic Science | Hamisi, M.; Lugomela, C.; Lyimo, T.; Bergman, B.; Díez, B. | 2017 | Zonas Costeras | 10.2989/16085914.2017.1334621 | https://www.tandfonline.com/doi/full/10.2989/16085914.2017.1334621 | 109-121 | Vol: 42 Issue: 2 | 1608-5914, 1727-9364 | Thomson Reuters ISI (SCIE) | English | Lake Big Momela, one of the East African soda lakes in Northern Tanzania characterised by highly saline-alkaline conditions, making them inhospitable to a range of organisms, although supporting massive growths of some adapted planktonic microorganisms that serve as food for birds, such as Lesser Flamingo. The temporal dynamics of plankton, with an emphasis on cyanobacteria, were examined in 2007 using morphological traits and ribosomal genetic markers (16S and 18S rRNA). Cyanobacterial genes encoding for hepatotoxins (mcyE and ndaF) were also screened. Rotifers and copepods dominated the zooplankton, whereas cyanobacteria, such as Anabaenopsis elenkinii and Arthrospira fusiformis dominated the phytoplankton community, and these being related to representatives in other East African soda lakes. The cyanobacteria community also showed distinct seasonal patterns influenced by environmental parameters, mainly salinity, pH and nitrate. Significant positive correlations were found between phytoplankton abundance and nitrate concentrations (r = 0.617, p = 0.033). No signals of the hepatotoxin synthetase genes mcyE and ndaF were retrieved from cyanobacteria during the whole year. In general, our data illustrate the presence of rich planktonic communities, including some unique and potentially endemic cyanobacteria. | |
| Framing climate change in Chile: Discourse analysis in digital media; [Encuadres del cambio climático en Chile: Análisis de discurso en prensa digital] | Convergencia | Hasbún-Mancilla, J.; Aldunce-Ide, P.; Blanco-Wells, G.; Browne-Sartori, R. | 2017 | Dimensión Humana | 10.29101/crcs.v0i74.4387 | http://convergencia.uaemex.mx/article/view/4387 | 161-186 | Vol: 24 Issue: 74 | 2448-5799 | Thomson Reuters ISI (SSCI) | Spanish | Este artículo presenta un análisis de discurso a cuatro medios de prensa digital en Chile respecto a la mitigación y la adaptación al cambio climático. La investigación, sin precedentes para el caso chileno, se orienta a conocer los encuadres noticiosos con que es comunicado el cambio climático, ya que los medios son la principal fuente de información del cambio climático para los tomadores de decisión y la ciudadanía. Los resultados muestran que los definidores primarios del tema son los actores gubernamentales de nivel nacional, y la invisibilización de las personas y organizaciones ciudadanas en el proceso. Vemos así un alto grado de consenso entre los actores visibilizados respecto al encuadre de oportunidad económica, y la ausencia de encuadres de ecología crítica. Las conclusiones apuntan a que este desbalance podría influir en un diseño de políticas públicas con un sesgo tecnocrático, perdiendo la posibilidad de construir una visión integral del desarrollo del país. | |
| Southern Annular Mode drives multicentury wildfire activity in southern South America | Proceedings of the National Academy of Sciences | Holz, A.; Paritsis, J.; Mundo, I.; Veblen, T.; Kitzberger, T.; Williamson, G.; Aráoz, E.; Bustos-Schindler, C.; González, M.; Grau, H.; Quezada, J. | 2017 | Cambio de Uso de Suelo | 10.1073/pnas.1705168114 | http://www.pnas.org/lookup/doi/10.1073/pnas.1705168114 | 9552-9557 | Vol: 114 Issue: 36 | 0027-8424, 1091-6490 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | The Southern Annular Mode (SAM) is the main driver of climate variability at mid to high latitudes in the Southern Hemisphere, affecting wildfire activity, which in turn pollutes the air and contributes to human health problems and mortality, and potentially provides strong feedback to the climate system through emissions and land cover changes. Here we report the largest Southern Hemisphere network of annually resolved tree ring fire histories, consisting of 1,767 fire-scarred trees from 97 sites (from 22 °S to 54 °S) in southern South America (SAS), to quantify the coupling of SAM and regional wildfire variability using recently created multicentury proxy indices of SAM for the years 1531–2010 AD. We show that at interannual time scales, as well as at multidecadal time scales across 37–54 °S, latitudinal gradient elevated wildfire activity is synchronous with positive phases of the SAM over the years 1665–1995. Positive phases of the SAM are associated primarily with warm conditions in these biomass-rich forests, in which widespread fire activity depends on fuel desiccation. Climate modeling studies indicate that greenhouse gases will force SAM into its positive phase even if stratospheric ozone returns to normal levels, so that climate conditions conducive to widespread fire activity in SAS will continue throughout the 21st century. © 2017, National Academy of Sciences. All rights reserved. |
| Assimilating satellite-based canopy height within an ecosystem model to estimate aboveground forest biomass: Assimilating Canopy Height Into Biomass | Geophysical Research Letters | Joetzjer, E.; Pillet, M.; Ciais, P.; Barbier, N.; Chave, J.; Schlund, M.; Maignan, F.; Barichivich, J.; Luyssaert, S.; Hérault, B.; von Poncet, F.; Poulter, B. | 2017 | Cambio de Uso de Suelo | 10.1002/2017GL074150 | http://doi.wiley.com/10.1002/2017GL074150 | 6823-6832 | Vol: 44 Issue: 13 | 00948276 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Despite advances in Earth observation and modeling, estimating tropical biomass remains a challenge. Recent work suggests that integrating satellite measurements of canopy height within ecosystem models is a promising approach to infer biomass. We tested the feasibility of this approach to retrieve aboveground biomass (AGB) at three tropical forest sites by assimilating remotely sensed canopy height derived from a texture analysis algorithm applied to the high-resolution Pleiades imager in the Organizing Carbon and Hydrology in Dynamic Ecosystems Canopy (ORCHIDEE-CAN) ecosystem model. While mean AGB could be estimated within 10% of AGB derived from census data in average across sites, canopy height derived from Pleiades product was spatially too smooth, thus unable to accurately resolve large height (and biomass) variations within the site considered. The error budget was evaluated in details, and systematic errors related to the ORCHIDEE-CAN structure contribute as a secondary source of error and could be overcome by using improved allometric equations. |
| Late Pleistocene Fuel Management and Human Colonization of the Atacama Desert, Northern Chile | Latin American Antiquity | Joly, D.; Santoro, C.; Gayo, E.; Ugalde, P.; March, R.; Carmona, R.; Marguerie, D.; Latorre, C. | 2017 | Biogeoquímica | 10.1017/laq.2016.8 | https://www.cambridge.org/core/journals/latin-american-antiquity/article/late-pleistocene-fuel-management-and-human-colonization-of-the-atacama-desert-northern-chile/148EDD42FFCA1DCAB84016CAA880F81D | 144-160 | Vol: 28 Issue: 1 | 1045-6635, 2325-5080 | Thomson Reuters ISI (SSCI; AHCI) | All Open Access; Bronze Open Access | English | Hunter-gatherers collected and used various woody species depending on the landscape, availability of plant communities, and sociocultural considerations. With extensive paleo-wetlands and groundwater-fed oases, the Atacama Desert was interspersed with riparian woodlands that provided vital resources (fuel, water, and game) at the end of the Pleistocene in areas such as the Pampa del Tamarugal (PdT) basin. We use anthracological analyses to determine the fuel management strategies of hunter-gatherer societies in this hyperarid environment and explore whether the “Principle of Least Effort” applies. First, we present the combustion qualities and characteristics of woody taxa from the Atacama and analyze possible exploitation strategies. Second, we use anthracological analyses from Quebrada Maní 12 (QM12), a late Pleistocene archaeological site (dated from 12,750 to 11,530 cal B.P.) located in the PdT basin, to show the prevalence of two woody species that were either freshly collected or gathered (very likely on purpose) from subfossil wood. Our results suggest that fuel selection strategies were based on prior knowledge of the qualities of these woody taxa and how they burned. Thus we conclude that fuel management was part of a number of social and economic decisions that allowed for effective colonization of this region. Furthermore, we stress the need for caution when using charcoal to exclusively date archaeological sites located in desert environments. , Hunter-gatherers collected and used various woody species depending on the landscape, availability of plant communities, and sociocultural considerations. With extensive paleo-wetlands and groundwater-fed oases, the Atacama Desert was interspersed with riparian woodlands that provided vital resources (fuel, water, and game) at the end of the Pleistocene in areas such as the Pampa del Tamarugal (PdT) basin. We use anthracological analyses to determine the fuel management strategies of hunter-gatherer societies in this hyperarid environment and explore whether the “Principle of Least Effort” applies. First, we present the combustion qualities and characteristics of woody taxa from the Atacama and analyze possible exploitation strategies. Second, we use anthracological analyses from Quebrada Maní 12 (QM12), a late Pleistocene archaeological site (dated from 12,750 to 11,530 cal B.P.) located in the PdT basin, to show the prevalence of two woody species that were either freshly collected or gathered (very likely on purpose) from subfossil wood. Our results suggest that fuel selection strategies were based on prior knowledge of the qualities of these woody taxa and how they burned. Thus we conclude that fuel management was part of a number of social and economic decisions that allowed for effective colonization of this region. Furthermore, we stress the need for caution when using charcoal to exclusively date archaeological sites located in desert environments. , Las sociedades de cazadores-recolectores del Cono Sur recolectaron y utilizaron diversas especies leñosas dependiendo de las condiciones del paisaje, las comunidades de plantas disponibles y consideraciones socio-culturales. Las cuencas hidrográficas, como Pampa del Tamarugal (PdT) en el Desierto de Atacama, contaban con extensos paleo-humedales y oasis sustentados con aguas subterráneas, intercalados con bosques ribereños que proporcionaron recursos vitales (combustible, agua y caza) hacia finales del Pleistoceno. Este estudio utiliza análisis antracológicos para definir las estrategias empleadas por los grupos de cazadores-recolectores para la gestión del combustible en este ambiente híper árido y explorar si dicho comportamiento social puede ser explicado por el “principio del menor esfuerzo”. En primer lugar, se presentan las cualidades y características de quema de los taxones leñosos del Desierto de Atacama y un análisis de sus estrategias de explotación. En segundo lugar, se utilizan los resultados de análisis antracológicos de muestras de carbones y maderas del sitio arqueológico Quebrada Maní 12 (QM12), ubicado en la PdT y asignado al Pleistoceno tardío (datado entre 12.750 y 11.530 cal a.P.). Estos muestran un predominio de dos especies leñosas recogidas como madera fresca ocolectadas, posiblemente en forma intencional, como “madera vieja”. Los resultados revelan que las estrategias de selección del material para la combustión requirieron de un conocimiento previo acerca de cómo se quemaban los taxones leñosos. Consecuentemente, se concluye que la gestión del combustible formó parte de las decisiones sociales y económicas que permitieron una colonización efectiva de esta región. Finalmente, se señala la necesidad de cautela a la hora de interpretar las cronologías arqueológicas basadas exclusivamente en dataciones sobre carbón en sitios ubicados en desiertos. |
| Forests and water in South America | Hydrological Processes | Jones, J.; Almeida, A.; Cisneros, F.; Iroumé, A.; Jobbágy, E.; Lara, A.; Lima, W.; Little, C.; Llerena, C.; Silveira, L.; Villegas, J. | 2017 | Servicios Ecosistémicos | 10.1002/hyp.11035 | http://onlinelibrary.wiley.com/doi/10.1002/hyp.11035/abstract | 972-980 | Vol: 31 Issue: 5 | 0885-6087 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | South America is experiencing rapid change in forest cover, of both native and planted forest. Forest cover loss is primarily attributable to fire, logging, and conversion of native forest to agriculture, pasture, and forest plantations, and types of change vary within and among the many diverse types of forests in South America. Major changes in forest cover and growing policy concerns underscore an urgent need for research on sustainable forest management and water ecosystem services in South America. Differences in land ownership and management objectives create trade-offs between wood production and water ecosystem services from forests. Work is needed to quantify how forest change and management affect ecosystem services, such as wood production versus water provision. Current scientific understanding of forest management effects on water ecosystem services in South America has important limitations, including a scarcity of long-term records and few long-term integrated watershed studies. Industry, government, universities, and local communities should collaborate on integrated applied studies of forests and water. Data archiving and publically available data are required. The creation of national networks and a multi-country South America network to identify and implement common water research protocols, share results, and explore their implications would promote common and well-supported policies. Hydrologists working in South America are well placed to tackle the challenges and opportunities for collaborative research that will maintain the intrinsic values and water ecosystem services provided by South America's forests. |
| The PMIP4 contribution to CMIP6 – Part 4: Scientific objectives and experimental design of the PMIP4-CMIP6 Last Glacial Maximum experiments and PMIP4 sensitivity experiments | Geoscientific Model Development | Kageyama, M.; Albani, S.; Braconnot, P.; Harrison, S.; Hopcroft, P.; Ivanovic, R.; Lambert, F.; Marti, O.; Peltier, W.; Peterschmitt, J.; Roche, D.; Tarasov, L.; Zhang, X.; Brady, E.; Haywood, A.; LeGrande, A.; Lunt, D.; Mahowald, N.; Mikolajewicz, U.; Nisancioglu, K.; Otto-Bliesner, B.; Renssen, H.... | 2017 | Ciudades Resilientes | 10.5194/gmd-10-4035-2017 | https://www.geosci-model-dev.net/10/4035/2017/ | 4035-4055 | Vol: 10 Issue: 11 | 1991-9603 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Last Glacial Maximum (LGM, 21 000 years ago) is one of the suite of paleoclimate simulations included in the current phase of the Coupled Model Intercomparison Project (CMIP6). It is an interval when insolation was similar to the present, but global ice volume was at a maximum, eustatic sea level was at or close to a minimum, greenhouse gas concentrations were lower, atmospheric aerosol loadings were higher than today, and vegetation and land-surface characteristics were different from today. The LGM has been a focus for the Paleoclimate Modelling Intercomparison Project (PMIP) since its inception, and thus many of the problems that might be associated with simulating such a radically different climate are well documented. The LGM state provides an ideal case study for evaluating climate model performance because the changes in forcing and temperature between the LGM and pre-industrial are of the same order of magnitude as those projected for the end of the 21st century. Thus, the CMIP6 LGM experiment could provide additional information that can be used to constrain estimates of climate sensitivity. The design of the Tier 1 LGM experiment (lgm) includes an assessment of uncertainties in boundary conditions, in particular through the use of different reconstructions of the ice sheets and of the change in dust forcing. Additional (Tier 2) sensitivity experiments have been designed to quantify feedbacks associated with land-surface changes and aerosol loadings, and to isolate the role of individual forcings. Model analysis and evaluation will capitalize on the relative abundance of paleoenvironmental observations and quantitative climate reconstructions already available for the LGM. |
| Research on Climate Change Policies and Rural Development in Latin America: Scope and Gaps | Sustainability | Locatelli, B.; Aldunce, P.; Fallot, A.; Le Coq, J.; Sabourin, E.; Tapasco, J. | 2017 | Agua y Extremos | 10.3390/su9101831 | http://www.mdpi.com/2071-1050/9/10/1831 | 1831 | Vol: 9 Issue: 10 | 2071-1050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Research on climate change policies can contribute to policy development by building an understanding of the barriers faced in policy processes, and by providing knowledge needed throughout policy cycles. This paper explores the thematic coverage of research on climate change policies related to rural areas, rural development, and natural resource management in Latin America. A three-tier framework is proposed to analyse the selected literature. The results show that research studies have focussed on the mitigation of greenhouse gas emissions from forests, and adaptations to climate change in agriculture. There is little policy research on other vulnerable sectors (e.g., water and health) and emitting sectors (e.g., energy and industry) in the context of rural development. Our analysis highlights the various research gaps that deserve increased scientific attention, including: cross-sector approaches, multi-level governance, and the stages of policy adoption, implementation and evaluation. In addition, the selected literature has a limited contribution to theoretical discussions in policy sciences. |
| Sensitivity of subtropical forest and savanna productivity to climate variability in South America, Uruguay | Journal of Vegetation Science | Lucas, C.; Ceroni, M.; Baeza, S.; Muñoz, A.; Brazeiro, A. | 2017 | Servicios Ecosistémicos | 10.1111/jvs.12475 | http://doi.wiley.com/10.1111/jvs.12475 | 192-205 | Vol: 28 Issue: 1 | 11009233 | Thomson Reuters ISI (SCIE) | English | Questions: Increasing climate variability has major effects on forest productivity, as well as transitions between forest and savanna ecosystems. While drought-induced declines in tropical forest productivity and forest loss is a global concern, forest expansion in subtropical South America predicted by climate models has received little attention. In the forest–grassland transition zone encompassing Uruguay, we ask: (1) how does climate variability affect woodland productivity and at what time scales; and (2) how do different woodland types (riparian, hillside and wooded savanna) differ in their sensitivity to climate variability?. Location: Forests and wooded savanna in Uruguay, subtropical southeast South America. Methods: Primary productivity was measured as the fraction of photosynthetically active radiation (fPAR) based on monthly normalized difference vegetation index (NDVI) from multitemporal (1998–2012) SPOT imagery at a 1 km × 1 km resolution, covering 19% of Uruguayan woodlands. The effects of accumulated rainfall and mean temperature on the productivity of riparian and hillside forests and wooded savanna were evaluated using correlations and time series analysis over multiple time windows ranging from 1–24 mo. Results: Inter-annual rainfall variability and seasonal temperatures affected forest productivity even though average conditions were largely non-limiting. Periods of exceptionally high rainfall and warm winters had positive effects on forest productivity, but hot summers had a negative effect on all woodland productivity. Riparian and hillside forest productivity was equally susceptible to drought, showing similar relationships to accumulated rainfall over multiple time periods, as well as similar susceptibility to high summer temperatures. Wooded savanna – a composite cover of trees and a grass/forb understorey – productivity was linked to seasonal rainfall over 3–6 mo, and in general showed the lowest correlation with inter-annual variability in rainfall. Conclusions: Results suggest functional convergence in the response of riparian and hillside forests to water deficit and hot summers. The increases in forest productivity with increasing rainfall and declining drought risk – as predicted by the IPCC for this region – are a potential mechanism for increased growth and future expansion of forests in this biogeographic transition zone. © 2016 International Association for Vegetation Science | |
| The Chilean Coastal Orographic Precipitation Experiment: Observing the Influence of Microphysical Rain Regimes on Coastal Orographic Precipitation | Journal of Hydrometeorology | Massmann, A.; Minder, J.; Garreaud, R.; Kingsmill, D.; Valenzuela, R.; Montecinos, A.; Fults, S.; Snider, J. | 2017 | Agua y Extremos | 10.1175/JHM-D-17-0005.1 | http://journals.ametsoc.org/doi/10.1175/JHM-D-17-0005.1 | 2723-2743 | Vol: 18 Issue: 10 | 1525-755X, 1525-7541 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The Chilean Coastal Orographic Precipitation Experiment (CCOPE) was conducted during the austral winter of 2015 (May-August) in the Nahuelbuta Mountains (peak elevation 1.3 km MSL) of southern Chile (38°S). CCOPE used soundings, two profiling Micro Rain Radars, a Parsivel disdrometer, and a rain gauge network to characterize warm and ice-initiated rain regimes and explore their consequences for orographic precipitation. Thirty-three percent of foothill rainfall fell during warm rain periods, while 50% of rainfall fell during ice-initiated periods. Warm rain drop size distributions were characterized by many more and relatively smaller drops than ice-initiated drop size distributions. Both the portion and properties of warm and ice-initiated rainfall compare favorably with observations of coastal mountain rainfall at a similar latitude in California. Orographic enhancement is consistently strong for rain of both types, suggesting that seeding from ice aloft is not a requisite for large orographic enhancement. While the data suggest that orographic enhancement may be greater during warm rain regimes, the difference in orographic enhancement between regimes is not significant. Sounding launches indicate that differences in orographic enhancement are not easily explainable by differences in low-level moisture flux or nondimensional mountain height between the regimes. |
| The pre-Columbian introduction and dispersal of Algarrobo (Prosopis, Section Algarobia) in the Atacama Desert of northern Chile | PLOS ONE | McRostie, V.; Gayo, E.; Santoro, C.; De Pol-Holz, R.; Latorre, C. | 2017 | Cambio de Uso de Suelo; Ciudades Resilientes | 10.1371/journal.pone.0181759 | http://dx.plos.org/10.1371/journal.pone.0181759 | e0181759 | Vol: 12 Issue: 7 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Archaeological and palaeoecological studies throughout the Americas have documented widespread landscape and environmental transformation during the pre-Columbian era. The highly dynamic Formative (or Neolithic) period in northern Chile (ca. 3700–1550 yr BP) brought about the local establishment of agriculture, introduction of new crops (maize, quinoa, manioc, beans, etc.) along with a major population increase, new emergent villages and technological innovations. Even trees such as the Algarrobos (Prosopis section Algarobia) may have been part of this transformation. Here, we provide evidence that these species were not native to the Atacama Desert of Chile (18–27S), appearing only in the late Holocene and most likely due to human actions. We assembled a database composed of 41 taxon specific AMS radiocarbon dates from archaeobotanical and palaeoecological records (rodent middens, leaf litter deposits), as well an extensive bibliographical review comprising archaeobotanical, paleoecological, phylogenetic and taxonomic data to evaluate the chronology of introduction and dispersal of these trees. Although Algarrobos could have appeared as early as 4200 yr BP in northernmost Chile, they only became common throughout the Atacama over a thousand years later, during and after the Formative period. Cultural and natural factors likely contributed to its spread and consolidation as a major silvicultural resource. |
| Native forest loss in the Chilean biodiversity hotspot: revealing the evidence | Regional Environmental Change | Miranda, A.; Altamirano, A.; Cayuela, L.; Lara, A.; González, M. | 2017 | Servicios Ecosistémicos | 10.1007/s10113-016-1010-7 | http://link.springer.com/article/10.1007/s10113-016-1010-7 | 285-297 | Vol: 17 Issue: 1 | 1436-3798 | Thomson Reuters ISI (SCIE; SSCI) | English | The understanding of the spatial and temporal patterns in land use and land cover (LULC) change is a key issue for conservation efforts. In the Chilean hotspot, different studies have attempted to understand variations of LULC change. Nevertheless, a broader understanding of common patterns and variability of LULC over the entire range of the hotspot is lacking. We performed a complete review of the different studies reporting LULC changes and performed a joint analysis of their results using an integrated comprehensive approach. We related the variation of LULC change to latitude, time period and vascular plant richness using generalized linear models. Overall, there were nine studies, which covered 36.5 % of the study area, and reported the loss of 19 % of native forest (782,120 ha) between 1973 and 2011. The highest net forest loss was observed in the 1970–1990 period. This decreased in the 1990–2000 period and rose again in the 2000–2010 period. This result reveals a continuous forest loss in the last 40 years. Conversion of native forest to shrublands is the most important contributor to net native forest loss, accounting for 45 % of the loss. However, in the area of greatest species richness native forests are mainly converted to exotic tree plantations. Chilean forestry model has proved successful in expanding exotic tree plantation, but so far it has not been compatible with native forest conservation and restoration. It is imperative to design a new forestry policy to assure the conservation of one of the most unique biodiversity hotspots worldwide. | |
| A solar radiation database for Chile | Scientific Reports | Molina, A.; Falvey, M.; Rondanelli, R. | 2017 | Zonas Costeras | 10.1038/s41598-017-13761-x | http://www.nature.com/articles/s41598-017-13761-x | art14823 | Vol: 7 Issue: 1 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Chile hosts some of the sunniest places on earth, which has led to a growing solar energy industry in recent years. However, the lack of high resolution measurements of solar irradiance becomes a critical obstacle for both financing and design of solar installations. Besides the Atacama Desert, Chile displays a large array of "solar climates" due to large latitude and altitude variations, and so provides a useful testbed for the development of solar irradiance maps. Here a new public database for surface solar irradiance over Chile is presented. This database includes hourly irradiance from 2004 to 2016 at 90 m horizontal resolution over continental Chile. Our results are based on global reanalysis data to force a radiative transfer model for clear sky solar irradiance and an empirical model based on geostationary satellite data for cloudy conditions. The results have been validated using 140 surface solar irradiance stations throughout the country. Model mean percentage error in hourly time series of global horizontal irradiance is only 0.73%, considering both clear and cloudy days. The simplicity and accuracy of the model over a wide range of solar conditions provides confidence that the model can be easily generalized to other regions of the world. |
| Techno-Economic Forecasts of Lithium Nitrates for Thermal Storage Systems | Sustainability | Montané, M.; Cáceres, G.; Villena, M.; O’Ryan, R. | 2017 | Dimensión Humana | 10.3390/su9050810 | http://www.mdpi.com/2071-1050/9/5/810 | art810 | Vol: 9 Issue: 5 | 2071-1050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Thermal energy storage systems (TES) are a key component of concentrated solar power (CSP) plants that generally use a NaNO3/KNO3 mixture also known as solar salt as a thermal storage material. Improvements in TES materials are important to lower CSP costs, increase energy efficiency and competitiveness with other technologies. A novel alternative examined in this paper is the use of salt mixtures with lithium nitrate that help to reduce the salt’s melting point and improve thermal capacity. This in turn allows the volume of materials required to be reduced. Based on data for commercial plants and the expected evolution of the lithium market, the technical and economic prospects for this alternative are evaluated considering recent developments of Lithium Nitrates and the uncertain future prices of lithium. Through a levelized cost of energy (LCOE) analysis it is concluded that some of the mixtures could allow a reduction in the costs of CSP plants, improving their competitiveness. |
| La Definición de Nuevos Estándares en Materia de Participación Ciudadana en el Sistema de Evaluación de Impacto Ambiental | Revista Derecho del Estado | Moraga Sariego, P. | 2017 | Dimensión Humana | 10.18601/01229893.n38.07 | https://revistas.uexternado.edu.co/index.php/derest/article/view/4931 | 177–198 | Issue: 38 | 2346-2051 | SciELO | All Open Access; Gold Open Access; Green Open Access | Spanish | La Ley 19.300, sobre Bases Generales del Medio Ambiente, del año 1994, brindó el primer marco legal para la protección ambiental en el país, en el contexto de la Cumbre de Río realizada dos años antes. Luego de las recomendaciones efectuadas por la OCDE en el sentido de fortalecer la institucionalidad ambiental (2005), el legislador dicta la Ley 20.417 que introduce la reforma ambiental (2010) y la Ley 20.600 que crea los tribunales ambientales (2012). La primera amplía el ámbito de aplicación de la participación ciudadana del sistema de evaluación de impacto ambiental; sin embargo, es el trabajo jurisprudencial del Segundo Tribunal Ambiental el que permitirá comprender el real alcance de la modificación legislativa. Esta judicatura especializada desarrolla nuevos estándares de participación ciudadana en el marco del proyecto de la Empresa de Ferrocarriles del Estado. Se trata de una interpretación amplia del principio en miras a una aplicación real y no únicamente formal del mismo, lo que contribuye al fortalecimiento de esta institución en relación al principio de acceso a la información y a la justicia en materia ambiental. |
| Análisis crítico de la judicialización del cambio climático y la economía baja en carbono frente a las categorías tradicionales del derecho | Revista de Derecho, Universidad de Concepción | Moraga Sariego, P.; Meckievi, S. | 2017 | Dimensión Humana | www.revistadederecho.com/pdf.php?id=3199 | 75-95 | Vol: año LXXXIV (Jul-Dic, 2016) Issue: 240 | 0303-9986 0718-591X | Latindex | El desarrollo de casos judiciales vinculados a los efectos y problemáticas del cambio climático comienza en los alrededores del año 2004 en Estados Unidos, para propagarse luego a Europa y Asia, desafiando a las categorías tradicionales del derecho frente a la necesidad de bridar una protección efectiva a los bienes jurídicos en juego. La regulación internacional definida recientemente en el marco del Acuerdo de París, agrega nuevos elementos para la profundización de este fenómeno, especialmente para países vulnerables, como lo es Chile. | |||
| Ecosystem engineering by Fascicularia bicolor in the canopy of the South-American temperate rainforest | Forest Ecology and Management | Ortega-Solís, G.; Díaz, I.; Mellado-Mansilla, D.; Tello, F.; Moreno, R.; Tejo, C. | 2017 | Cambio de Uso de Suelo | 10.1016/j.foreco.2017.06.020 | http://linkinghub.elsevier.com/retrieve/pii/S0378112717302074 | 417-428 | Vol: 400 | 0378-1127 | Thomson Reuters ISI (SCIE) | English | Ecosystem engineers are organisms that modify habitats and resource flows, they therefore could have a disproportionate impact on the diversity of ecological communities. Evidence suggests that trash basket epiphytes (TBE) can be considered ecosystem engineers of forest canopies, due to their relationship with arboreal soil availability and treetop communities. Here we evaluated whether the TBE Fascicularia bicolor (Bromeliaceae), modulates temperature and humidity in the forest canopy. We also investigated if this bromeliad is related with greater arboreal soil accumulation and is associated to higher diversity of other epiphytic plants and invertebrates in the canopy of the South-American temperate rainforest (SATR), in Chile. We measured temperature and humidity in ten trees within the forest before and after the experimental addition of F. bicolor. We also related the presence of F. bicolor with occurrence of soil macrofauna and other canopy dwelling plants in a comparative field survey. Temperature variability in the canopy was reduced by F. bicolor. Soil availability was higher in siteswith mats of F. bicolor. The richness of vascular epiphytes was unaltered by the presence of F. bicolor,but species composition differed between sites with and without mats on each tree. At the group level,the cover of lichens and bryophytes was greater in sites without F. bicolor, while vascular epiphytes showa larger cover in sites with F. bicolor. The species richness of invertebrates increased in treetop sites colonized by F. bicolor but species composition was not different from soil in branch bifurcations. Our resultsshow that F. bicolor must be considered in forest management practices to determine which trees must belogged, in order to preserve the viability of populations of these key organisms in the treetops of South-American temperate rainforests. | |
| Monitoring global drought using the self-calibrating Palmer Drought Severity Index | State of the Climate 2016, Bulletin of the American Meteorological Society | Osborn, T.; Barichivich, J.; Harris, I.; van der Schrier, G.; Jones, P. | 2017 | Cambio de Uso de Suelo | 10.1175/2017BAMSStateoftheClimate.1 | http://journals.ametsoc.org/doi/10.1175/2017BAMSStateoftheClimate.1 | Si-S280 | Vol: 98 Issue: 8 | 0003-0007 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | In 2016, the dominant greenhouse gases released into Earth's atmosphere-carbon dioxide, methane, and nitrous oxide-continued to increase and reach new record highs. The 3.5 ± 0.1 ppm rise in global annual mean carbon dioxide from 2015 to 2016 was the largest annual increase observed in the 58-year measurement record. The annual global average carbon dioxide concentration at Earth's surface surpassed 400 ppm (402.9 ± 0.1 ppm) for the first time in the modern atmospheric measurement record and in ice core records dating back as far as 800000 years. One of the strongest El Niño events since at least 1950 dissipated in spring, and a weak La Niña evolved later in the year. Owing at least in part to the combination of El Niño conditions early in the year and a long-term upward trend, Earth's surface observed record warmth for a third consecutive year, albeit by a much slimmer margin than by which that record was set in 2015. Above Earth's surface, the annual lower troposphere temperature was record high according to all datasets analyzed, while the lower stratospheric temperature was record low according to most of the in situ and satellite datasets. Several countries, including Mexico and India, reported record high annual temperatures while many others observed near-record highs. A week-long heat wave at the end of April over the northern and eastern Indian peninsula, with temperatures surpassing 44°C, contributed to a water crisis for 330 million people and to 300 fatalities. In the Arctic the 2016 land surface temperature was 2.0°C above the 1981-2010 average, breaking the previous record of 2007, 2011, and 2015 by 0.8°C, representing a 3.5°C increase since the record began in 1900. The increasing temperatures have led to decreasing Arctic sea ice extent and thickness. On 24 March, the sea ice extent at the end of the growth season saw its lowest maximum in the 37-year satellite record, tying with 2015 at 7.2% below the 1981-2010 average. The September 2016 Arctic sea ice minimum extent tied with 2007 for the second lowest value on record, 33% lower than the 1981-2010 average. Arctic sea ice cover remains relatively young and thin, making it vulnerable to continued extensive melt. The mass of the Greenland Ice Sheet, which has the capacity to contribute ∼7 m to sea level rise, reached a record low value. The onset of its surface melt was the second earliest, after 2012, in the 37-year satellite record. Sea surface temperature was record high at the global scale, surpassing the previous record of 2015 by about 0.01°C. The global sea surface temperature trend for the 21st centuryto-date of +0.162°C decade-1 is much higher than the longer term 1950-2016 trend of +0.100°C decade-1. Global annual mean sea level also reached a new record high, marking the sixth consecutive year of increase. Global annual ocean heat content saw a slight drop compared to the record high in 2015. Alpine glacier retreat continued around the globe, and preliminary data indicate that 2016 is the 37th consecutive year of negative annual mass balance. Across the Northern Hemisphere, snow cover for each month from February to June was among its four least extensive in the 47-year satellite record. Continuing a pattern below the surface, record high temperatures at 20-m depth were measured at all permafrost observatories on the North Slope of Alaska and at the Canadian observatory on northernmost Ellesmere Island. In the Antarctic, record low monthly surface pressures were broken at many stations, with the southern annular mode setting record high index values in March and June. Monthly high surface pressure records for August and November were set at several stations. During this period, record low daily and monthly sea ice extents were observed, with the November mean sea ice extent more than 5 standard deviations below the 1981-2010 average. These record low sea ice values contrast sharply with the record high values observed during 2012-14. Over the region, springtime Antarctic stratospheric ozone depletion was less severe relative to the 1991-2006 average, but ozone levels were still low compared to pre-1990 levels. Closer to the equator, 93 named tropical storms were observed during 2016, above the 1981-2010 average of 82, but fewer than the 101 storms recorded in 2015. Three basins-the North Atlantic, and eastern and western North Pacific-experienced above-normal activity in 2016. The Australian basin recorded its least active season since the beginning of the satellite era in 1970. Overall, four tropical cyclones reached the Saffir-Simpson category 5 intensity level. The strong El Niño at the beginning of the year that transitioned to a weak La Niña contributed to enhanced precipitation variability around the world. Wet conditions were observed throughout the year across southern South America, causing repeated heavy flooding in Argentina, Paraguay, and Uruguay. Wetter-than-usual conditions were also observed for eastern Europe and central Asia, alleviating the drought conditions of 2014 and 2015 in southern Russia. In the United States, California had its first wetter-than-average year since 2012, after being plagued by drought for several years. Even so, the area covered by drought in 2016 at the global scale was among the largest in the post-1950 record. For each month, at least 12% of land surfaces experienced severe drought conditions or worse, the longest such stretch in the record. In northeastern Brazil, drought conditions were observed for the fifth consecutive year, making this the longest drought on record in the region. Dry conditions were also observed in western Bolivia and Peru; it was Bolivia's worst drought in the past 25 years. In May, with abnormally warm and dry conditions already prevailing over western Canada for about a year, the human-induced Fort McMurray wildfire burned nearly 590000 hectares and became the costliest disaster in Canadian history, with $3 billion (U.S. dollars) in insured losses. |
| Hunter-Gatherer Mobility Strategies in the High Andes of northern Chile during the late Pleistocene-early Holocene Transition (ca. 11,500-9,500 CAL B.P.) | Journal of Field Archaeology | Osorio, D.; Capriles, J.; Ugalde, P.; Herrera, K.; Salas, C.; Sepulveda, M.; Gayo, E.; Latorre, C.; Jackson, D.; Santoro, C. | 2017 | Biogeoquímica | 10.1080/00934690.2017.1322874 | http://www.tandfonline.com/doi/abs/10.1080/00934690.2017.1322874?journalCode=yjfa20 | 228-240 | Vol: 42 Issue: 3 | 0093-4690 | Thomson Reuters ISI (AHCI) | English | The high Andes of western South America feature extreme ecological conditions that impose important physiological constraints on humans including high-elevation hypoxia and cold stress. This leads to questions regarding how these environments were colonized by the first waves of humans that reached them during the late Pleistocene. Based on previous research, and aided by human behavioral ecology principles, we assess hunter-gatherer behavioral strategies in the Andean highlands during the late Pleistocene and early Holocene. Specifically, we formulate three mobility strategies and their archaeological expectations and test these using technological and subsistence evidence from the six earliest well-dated highland sites in northern Chile. Our results suggest that all of the studied sites were temporarily occupied for hunting, processing animals, and toolkit maintenance. The sites also exhibit shared technological features within a curatorial strategy albeit with different occupation intensities. From this evidence, we infer that the initial occupations of the highlands were logistical and probably facilitated by increased local resource availability during a period of environmental amelioration. |
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| The Dry Puna as an ecological megapatch and the peopling of South America: Technology, mobility, and the development of a late Pleistocene/early Holocene Andean hunter-gatherer tradition in northern Chile | Quaternary International | Osorio, D.; Steele, J.; Sepúlveda, M.; Gayo, E.; Capriles, J.; Herrera, K.; Ugalde, P.; De Pol-Holz, R.; Latorre, C.; Santoro, C. | 2017 | Cambio de Uso de Suelo; Ciudades Resilientes | 10.1016/j.quaint.2017.07.010 | https://linkinghub.elsevier.com/retrieve/pii/S1040618216312368 | 41-53 | Vol: 461 | 10406182 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Current scientific evidence shows that humans colonized South America at least 15,000 years ago, but there are still many unknown aspects of this process, including the major and minor migratory routes involved, and the pattern of successive occupation of a diverse continental mosaic of ecosystems. In this context, the role of the Andean highlands ( 3400 meters above sea level) has been neglected, because of the supposedly harsh conditions for humans including hypoxia and cold climate. Nevertheless, the environmental and cultural resources available in the high Andes constitutes an important “megapatch” that should be assessed in terms of human settlement patterns. We review the evidence for late Pleistocene/early Holocene hunter-gatherer occupation of one part of this megapatch, the northern Chilean Dry Puna, in its palaeoecological context. We focus on lithic technology, faunal remains, radiocarbon dates, and other archaeological materials related to different social activities, which allow us to suggest that groups of hunter-gatherers organized and adapted their way of life to highland ecosystems through logistical mobility, and curatorial strategies for lithic tool kits that included projectile points and other formalized tools. The morphology and technological processes involved are recognized over vast territories along the high Andes. We identify this material expression as the high south central Andean Archaic hunter-gatherer tradition, which also featured long distance mobile settlement systems and communication processes over this broad and distinct megapatch. More speculatively, we outline the hypothesis that these highland ecosystems constituted a suitable migratory route that may have been key for the early peopling of the continent, and contrast it with the alternative hypothesis of the initially secondary and seasonally intermittent exploitation of this habitat by hunter-gatherers dispersing along the Pacific coastal corridor. |
| Carbon allocation to growth and storage in two evergreen species of contrasting successional status | American Journal of Botany | Piper, F.; Sepúlveda, P.; Bustos-Salazar, A.; Zúñiga-Feest, A. | 2017 | Cambio de Uso de Suelo | 10.3732/ajb.1700057 | http://doi.wiley.com/10.3732/ajb.1700057 | 654-662 | Vol: 104 Issue: 5 | 0002-9122, 1537-2197 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Premise of the study: A prevailing hypothesis in forest succession is that shade-tolerant species grow more slowly than shade-intolerant species, across light conditions, because they prioritize carbon (C) allocation to storage. We examined this hypothesis in a confamilial pair of species, including one of the fastest-growing tree species in the world (Eucalyptus globulus) and a shade-tolerant, slow-growing species (Luma apiculata). Methods: Seedlings were subjected to one out of four combinations of light (high vs. low) and initial defoliation (90% defoliated vs. nondefoliated) for four months. Growth, C storage concentration in different organs, leaf shedding, and lateral shoot formation were measured at the end of the experiment. Key results: Eucalyptus globulus grew faster than L. apiculata in high light, but not in low light. Both species had lower C storage concentration in low than in high light, but similar C storage concentrations in each light condition. Defoliation had no effect on C storage, except in the case of the old leaves of both species, which showed lower C storage levels in response to defoliation. Across treatments, leaf shedding was 96% higher in E. globulus than in L. apiculata while, in contrast, lateral shoot formation was 87% higher in L. apiculata. Conclusions: In low light, E. globulus prioritized C storage instead of growth, whereas L. apiculata prioritized growth and lateral branching. Our results suggest that shade tolerance depends on efficient light capture rather than C conservation traits. Keywords: C starvation; Eucalyptus globulus; Luma apiculata; Myrtaceae; defoliation; growth–survival tradeoff; leaf shedding; starch; succession; understory. |
| Potencial de los anillos de crecimiento de Pilgerodendron uviferum para el estudio histórico de las Iglesias de Chiloé, Patrimonio de la Humanidad | Bosque (Valdivia) | Puchi, P.; Muñoz, A.; González, M.; Abarzúa, A.; Araya, K.; Towner, R.; Fitzek, R.; Holz, A.; Stahle, D. | 2017 | Agua y Extremos; Cambio de Uso de Suelo | 10.4067/S0717-92002017000100012 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-92002017000100012&lng=en&nrm=iso&tlng=en | 109-121 | Vol: 38 Issue: 1 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Las iglesias de Chiloé son antiguas estructuras de madera reconocidas patrimonio de la humanidad por la UNESCO. Gran parte de su historia de construcción y reparaciones aún se desconoce. Considerando que muchas de las iglesias de Chiloé fueron construidas utilizando madera de Pilgerodendron uviferum, el objetivo de este trabajo fue evaluar el potencial de esta especie para datar piezas de madera de dos de estas históricas construcciones: las iglesias de Vilupulli e Ichuac. En Vilupulli se dataron piezas de 311 y 181 años provenientes de los pilares de la torre. Estas piezas fueron fechadas con cronologías de ancho de anillos de P. uviferum cercanas a las dos iglesias. También utilizando estas cronologías se dataron piezas de 79, 89, 97 y 135 años obtenidas a partir de los pilotes que sostienen el piso de la iglesia de Ichuac. Considerando que Vilupulli fue construida a principios del siglo XX, es posible que las muestras de la torre que presentaron fechas cercanas a 1918, sean parte del proceso tardío de construcción de la iglesia o de una restauración posterior. Por su parte, Ichuac fue construida a finales del siglo XIX, por lo que las piezas del piso que dataron entre 19201929, formarían parte de una posible restauración no descrita previamente en archivos históricos, la cual pudo ocurrir incluso varios años posterior a la fecha del anillo más reciente encontrado en las piezas estudiadas. Se concluye que P. uviferum tiene alto potencial para estudios históricos en estructuras patrimoniales en el sur de Chile. |
| Climate change education and literacy at the Faculty of Physical and Mathematical Sciences of the University of Chile | International Journal of Global Warming | Rojas, M.; Mac-Lean, C.; Morales, J.; Monares, A.; Fustos, R. | 2017 | Modelación y Sistemas de Observación | 10.1504/IJGW.2017.084785 | https://www.inderscience.com/offer.php?id=84785 | 1-19 | Vol: 12 Issue: 3-4 | 1758-2083 | Thomson Reuters ISI (SCIE) | English | Considering the role that higher education institutions (HEIs) play in terms of catalysing change within societies, over the past years, sustainability initiatives within HEIs have flourished worldwide. Likewise, the scientific evidence of anthropogenic climate change has been on the political and academic agenda for decades, thus, the importance of ameliorating climate change education and literacy both at the society and university training levels. Accordingly, certain questions arise: What are the most effective current climate change educational methodologies? Which road map would be the most appropriate to be suggested to HEIs to promote climate change literacy for future professionals? In order to begin addressing these questions, the Faculty of Mathematical and Physical Sciences of the University of Chile (FCFM) approach to climate change teaching and literacy is here described. The later contemplates the history of the institutionalisation of sustainability at the FCFM, collection of courses and minors for students which incorporate climate change related-topics, as well as climate change related research centres. Keywords: | |
| Anatomic anomalies in annual tree-rings of Austrocedrus chilensis (D. Don) Pic.-Serm. et Bizzarri in its northern distribution range | Gayana. Botánica | Rojas-Badilla, M.; Álvarez, C.; Velásquez-Álvarez, G.; Hadad, M.; Le Quesne, C.; Christie, D. | 2017 | Agua y Extremos | 10.4067/S0717-66432017000200269 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432017000200269&lng=en&nrm=iso&tlng=en | 269-281 | Vol: 74 Issue: 2 | 0717-6643 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Tree-ring anatomical anomalies have received little attention in southern South American trees, however they can contain valuable intra-annual environmental information. This study addressed for the first time the three most frequent tree- ring anomalies recorded in the northern and oldest known Austrocedrus chilensis forest in central Chile (32-35°S). Three anatomic anomalies described were: partially absent rings, intra-annual bands and frost rings. Partially absent rings resulted from cambial inactivity during a complete growing period and require dendrochronological tools to be detected. Intra- annual bands are consequence of the abundance-shortage of environmental resources during the growing season and can be detected by examining the undefined late-wood boundaries. Frost rings, are caused by extreme low temperatures and are characterized by collapsed cells in the tree-ring growth. Results indicate that the northern most population exhibited the highest rate of absent rings, while the occurrence of intra-annual bands seems to be rather minor in the study area. Finally, frost rings are registered mainly in the younger trees in all three studied sites. These results suggest the potential for future spatio-temporal studies that examine the frequency of these anatomical anomalies in A. chilensis chronologies along its wide geographical distribution. This will complement the current environmental information recorded by its growth rates. |
| ¿Cómo llueve cuando llueve en Atacama ? | PRP “Generación de información y monitoreo del Fenómeno El Niño” - IGP | Rondanelli, R. | 2017 | Biogeoquímica | http://intranet.igp.gob.pe/sysppr/results/result_66/Boletin_Tecnico_PPR_El_Nino_IGP_201703.pdf | 4-6 | Vol: 4 Issue: 3 | Cerca de los 24°S y enfrentando la costa oriental de Sudamérica yace el desierto de Atacama, el más árido del planeta. El pueblo de Quillagua (21.6 6°S, 69 69°W), un oasis del Río Loa que nace en los Andes alimentando por la precipitación Altiplánica del verano, presenta la precipitación anual más pequeña de la que se tiene registro en el planeta (0.05 mm/ año, Middleton, 2001). | |||||
| Continuities and discontinuities in the socio-environmental systems of the Atacama Desert during the last 13,000 years | Journal of Anthropological Archaeology | Santoro, C.; Capriles, J.; Gayo, E.; de Porras, M.; Maldonado, A.; Standen, V.; Latorre, C.; Castro, V.; Angelo, D.; McRostie, V.; Uribe, M.; Valenzuela, D.; Ugalde, P.; Marquet, P. | 2017 | Biogeoquímica | 10.1016/j.jaa.2016.08.006 | http://www.sciencedirect.com/science/article/pii/S0278416516301155 | 28-39 | Vol: 46 | 0278-4165 | Thomson Reuters ISI (SSCI; AHCI) | English | Understanding how human societies interacted with environmental changes is a major goal of archaeology and other socio-natural sciences. In this paper, we assess the human-environment interactions in the Pampa del Tamarugal (PDT) basin of the Atacama Desert over the last 13,000 years. By relying on a socio-environmental model that integrates ecosystem services with adaptive strategies, we review past climate changes, shifting environmental conditions, and the continuities and discontinuities in the nature and intensity of the human occupation of the PDT. As a result we highlight the importance of certain key resources such as water, an essential factor in the long-term trajectory of eco-historical change. Without water the outcome of human societies becomes hazardous. | |
| Loco or no Loco? Holocene Climatic Fluctuations, Human Demography, and Community Based Management of Coastal Resources in Northern Chile | Frontiers in Earth Science | Santoro, C.; Gayo, E.; Carter, C.; Standen, V.; Castro, V.; Valenzuela, D.; De Pol-Holz, R.; Marquet, P.; Latorre, C. | 2017 | Cambio de Uso de Suelo; Ciudades Resilientes | 10.3389/feart.2017.00077 | http://journal.frontiersin.org/article/10.3389/feart.2017.00077/full | na | Vol: 5 | 2296-6463 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The abundance of the southern Pacific mollusk loco (Concholepas concholepas), among other conspicuous marine supplies, are often cited as critical resources behind the long-term cultural and demographic fluctuations of prehistoric hunter-gatherers in the coastal Atacama Desert. These societies inhabited one of the world’s most productive marine environments flanked by one the world’s driest deserts. Both of these environments have witnessed significant ecological variation since people first colonized themat the end of the Pleistocene (c. 13,000 cal yr BP). Here, we examine the relationship between the relative abundance of shellfish (a staple resource) along a 9,500-year sequence of archeological shell midden accumulations at Caleta (a small inlet or cove) Vitor, with past demographic trends (established via summed probability distributions of radiocarbon ages) and technological innovations together with paleoceanographic data on past primary productivity. We find that shellfish extraction varied considerably from one cultural period to the next in terms of the number of species and their abundance, with diversity increasing during periods of regionally decreased productivity. Such shifts in consumption patterns are considered community based management decisions, and for the most part they were synchronous with large and unusual regional demographic fluctuations experienced by prehistoric coastal societies in northern Chile. When taken together with their technological innovations, our data illustrates how these human groups tailored their socio-cultural patterns to what were often abrupt and prolonged environmental changes throughout the Holocene. |
| Psychology's contributions to address the human dimensions of climate change in Chile (second part); [Contribuciones de la psicología al abordaje de la dimensión humana del cambio climático en Chile (segunda parte)] | Interdisciplinaria | Sapiains, R.; Ugarte, A. | 2017 | Gobernanza e Interfaz Ciencia y Política | 10.16888/interd.2017.34.2.2 | http://www.ciipme-conicet.gov.ar/ojs/index.php/interdisciplinaria/article/view/332 | 259-274 | Vol: 34 Issue: 2 | 0325-8203 | Thomson Reuters ISI (ESCI) | Spanish | En la primera parte de este trabajo se presentó una revisión bibliográfica sobre el estudio de la dimensión humana del cambio climático, organizado en cuatro grandes ejes de investigación: la comunicación del cambio climático, el estudio de creencias, actitudes, valores y conductas relacionadas con el problema, la identificación de facilitadores y barreras psicológicas para la implementación de prácticas de mitigación y la adaptación y los impactos del cambio climático en la salud mental. En esta segunda parte se informan avances en esta área en el contexto latinoamericano, para posteriormente identificar aquellos ámbitos en los que la Psicología puede contribuir tanto en los planes para el cambio climático como en estudios de caso desarrollados en Chile. Como resultado se proponen cuatro áreas prioritarias: (1) creencias, actitudes, valores y conductas (2) educación y sensibilización, (3) participación ciudadana y (4) salud mental y bienestar social. La investigación en estos ejes puede contribuir al desarrollo de estrategias, políticas y planes más efectivos al profundizar en la dimensión humana del cambio climático en el particular contexto de Chile. | |
| Psychology's contributions to address the human dimensions of climate change in Chile (first part); [Contribuciones de la psicología al abordaje de la dimensión humana del cambio climático en Chile (primera parte)] | Interdisciplinaria | Sapiains, R.; Ugarte, A. | 2017 | Gobernanza e Interfaz Ciencia y Política | 10.16888/interd.2017.34.1.6 | http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1668-70272017000100006&lng=es&nrm=iso | 91-105 | Vol: 34 Issue: 1 | 0325-8203 | SciELO | Spanish | Múltiples estudios señalan que para abordar integralmente la problemática del cambio climático es fundamental incorporar factores psicológicos y sociales en el diseño, implementación y evaluación de estrategias de mitigación y adaptación. Estos factores resultan claves para incrementar la importancia del cambio climático en la agenda pública, favorecer un mayor involucramiento ciudadano y fortalecer la resiliencia individual, social e institucional, así como el im pacto de las políticas. No obstante, en Chile el estudio de los aspectos psicológicos del cambio climático es muy limitado. Por su extensión este trabajo se presenta en dos partes. En esta primera parte se presenta una revisión bibliográfica que explora los principales ámbitos del cambio climático en los que la Psicología puede contribuir para comprender las complejidades del problema. Esto se organiza en cuatro grandes ejes: (1) la comunicación del cambio climático, (2) el estudio de creencias, actitudes, valores y conductas relacionadas con el problema, (3) la identificación de facilitadores y barreras psicológicas para la implementación de prácticas de mitigación y adaptación y (4) los impactos del cambio climático en la salud mental. Estos ejes constituyen un marco de referencia para el posterior desarrollo de ámbitos de acción que se apliquen específicamente al contexto chileno. | |
| Meteorological Interpretation of Orographic Precipitation Gradients along an Andes West Slope Basin at 30°S (Elqui Valley, Chile) | Journal of Hydrometeorology | Scaff, L.; Rutllant, J.; Rahn, D.; Gascoin, S.; Rondanelli, R. | 2017 | Biogeoquímica | 10.1175/JHM-D-16-0073.1 | http://journals.ametsoc.org/doi/10.1175/JHM-D-16-0073.1 | 713-727 | Vol: 18 Issue: 3 | 1525-755X | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | To better forecast streamflow and water resource availability, it is important to have an understanding of the meteorological drivers of the orographic precipitation gradient (OPG), especially critical in semiarid mountainous areas. Although forced ascent over topography typically results in precipitation increasing with altitude (positive OPGs), mean annual OPGs and especially OPGs associated with individual storms can change widely in magnitude and even sign. Precipitation measurements from the Elqui Valley in the semiarid Andes of Chile (30°S) reveal a mean annual OPG of 6.3 mm km−1 (millimeters of precipitation over kilometers in elevation) ranging from −42 to 52 mm km−1 for individual storms over the last 35 years (1979–2013). Reanalysis data and precipitation measurements are used to characterize the observed OPG in this region in relation with their synoptic-scale flow. It is found that the Froude number correlates positively with the OPG, reflecting stronger zonal winds and less static stability during storms that have positive OPGs. Altitude of the Andes barrier jet shows only a weak relationship with the OPG. Significant storms with positive OPGs are typically linked with an austral blocking of the westerlies and an equatorward migration of the midlatitude storm track. For negative OPGs, either a cutoff low or the northern edge of a surface migratory cyclone reaches the Elqui Valley in such a way that significant rainfall only occurs in the near-coastal region without major snowfall accumulation over the Andes. |
| Implementation of methane cycling for deep-time global warming simulations with the DCESS Earth system model (version 1.2) | Geoscientific Model Development | Shaffer, G.; Fernández Villanueva, E.; Rondanelli, R.; Pedersen, J.; Olsen, S.; Huber, M. | 2017 | Zonas Costeras | 10.5194/gmd-10-4081-2017 | https://www.geosci-model-dev.net/10/4081/2017/ | 4081-4103 | Vol: 10 Issue: 11 | 1991-9603 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Geological records reveal a number of ancient, large and rapid negative excursions of the carbon-13 isotope. Such excursions can only be explained by massive injections of depleted carbon to the Earth system over a short duration. These injections may have forced strong global warming events, sometimes accompanied by mass extinctions such as the Triassic-Jurassic and end-Permian extinctions 201 and 252 million years ago, respectively. In many cases, evidence points to methane as the dominant form of injected carbon, whether as thermogenic methane formed by magma intrusions through overlying carbon-rich sediment or from warming-induced dissociation of methane hydrate, a solid compound of methane and water found in ocean sediments. As a consequence of the ubiquity and importance of methane in major Earth events, Earth system models for addressing such events should include a comprehensive treatment of methane cycling but such a treatment has often been lacking. Here we implement methane cycling in the Danish Center for Earth System Science (DCESS) model, a simplified but well-tested Earth system model of intermediate complexity. We use a generic methane input function that allows variation in input type, size, timescale and ocean–atmosphere partition. To be able to treat such massive inputs more correctly, we extend the model to deal with ocean suboxic/anoxic conditions and with radiative forcing and methane lifetimes appropriate for high atmospheric methane concentrations. With this new model version, we carried out an extensive set of simulations for methane inputs of various sizes, timescales and ocean–atmosphere partitions to probe model behavior. We find that larger methane inputs over shorter timescales with more methane dissolving in the ocean lead to ever-increasing ocean anoxia with consequences for ocean life and global carbon cycling. Greater methane input directly to the atmosphere leads to more warming and, for example, greater carbon dioxide release from land soils. Analysis of synthetic sediment cores from the simulations provides guidelines for the interpretation of real sediment cores spanning the warming events. With this improved DCESS model version and paleo-reconstructions, we are now better armed to gauge the amounts, types, timescales and locations of methane injections driving specific, observed deep-time, global warming events. |
| Climate change and resilience of deciduous Nothofagus forests in central-east Chilean Patagonia over the last 3200 years: RESILIENCE OF DECIDUOUS NOTHOFAGUS FORESTS IN PATAGONIA | Journal of Quaternary Science | Simi, E.; Moreno, P.; Villa-Martínez, R.; Vilanova, I.; de Pol-Holz, R. | 2017 | Agua y Extremos; Cambio de Uso de Suelo | 10.1002/jqs.2948 | http://doi.wiley.com/10.1002/jqs.2948 | 845-856 | Vol: 32 Issue: 6 | 0267-8179 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | We examine the response of Nothofagus forests to climate change and disturbance regimes over the last 3200 years near Coyhaique (45°S), central–east Chilean Patagonia, using fine‐resolution pollen and charcoal records from lake sediment cores. Closed‐canopy deciduous Nothofagus forests have dominated the region with little variation until the arrival of Chilean–European settlers, suggesting a predominance of cool‐temperate and wet conditions. Within this state we identify centennial‐scale episodes of forest fragmentation, increase in littoral macrophytes and volcanic/paleofire disturbance between 2700 and 3000 cal a BP, 2200 and 2500 cal a BP and over the last ∼250 years, which we interpret as intervals with negative hydrologic balance. Natural variability caused little impact on the physiognomy and composition of the vegetation in pre‐European time, in contrast to the accelerated shift that started during the late 19th century associated with deforestation, homogenization and synchronization of ecosystem changes at the landscape level, and spread of exotic plant species brought by Chilean and European settlers during a warm/dry interval. The resilience of deciduous Nothofagus forests to natural disturbance regimes and climate change was exceeded by large‐scale human disturbance since the late 19th century by fire, timber exploitation and livestock grazing. These disturbances caused an ecosystem shift towards artificial meadows and scrublands with frequent high‐magnitude fires. |
| SDR Cloud Radar development with reused radio telescope components | Toledo, F.; Rodriguez, R.; Rondanelli, R.; Aguirre, R.; Diaz, M. | 2017 | Zonas Costeras | 10.1109/GRSS-CHILE.2017.7996016 | http://ieeexplore.ieee.org/document/7996016/ | 1-5 | Not indexed | English | The ongoing implementation of a fog observatory in a coastal fog forest in northern Chile is expected to provide valuable information to improve our comprehension of these ecosystems alongside retrieving valuable data to fog scientists. Observing this opportunity and the increase on radio astronomy instrumental it is proposed to develop a low-cost Cloud Radar reutilizing obsolete but operative radio telescope components and software defined radios for modulation. Only preliminary tests have been conducted so far to test the viability of this approach. These tests show that it is in fact possible to build an emitter and receiver operating at 35 GHz using radio telescope components as a Radio Frequency front-end, and that the detected echo coming from the signal is affected by the presence of liquid water droplets in the air. Further development is being carried on the prototype to enable the detection of fog droplets in the boundary layer up to 2 km of height. | ||||
| Applying a distinction. A systemic-constructivist program for qualitative social science research; [Aplicar una distinción. Un programa sistémicoconstructivista para la investigación social cualitativa] | Revista Mad | Urquiza, A.; Billi, M.; Leal, T. | 2017 | Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política | 10.5354/0718-0527.2017.47269 | https://revistamad.uchile.cl/index.php/RMAD/article/view/47269/49293 | 21-53 | Vol: - Issue: 37 | 07180527 | Thomson Reuters ISI (ESCI) | Spanish | At least since the XVIII century, the 'problem of induction', that is, how to justify the abstractions derived from any empirical observation, has been at the core of a fiery debate both within the philosophy of science, and the praxis of social sciences. Refuting the allegation of 'empirical closure' raised against Niklas Luhmann's Social Systems Theory, we claim that it delivers a privileged epistemological and theoretical platform to face such a dilemma, since it highlights the necessary conditions to produce an 'abductive' reasoning. By way of discussing, on the one hand, Luhmann's understanding of knowledge and science, and on the other, diverse attempts to apply empirically the understand the role and relationships of the principles of theoretical plausibility and empirical grounding within social science research. Based on that, the article identifies the criteria of 'isomorphism', 'perspectivism', transparency' and 'iterability' as indicators of scientific acceptability of a systemic-constructivist research, and offers orientations for the design of such a research. © CC BY-NC 3.0 CL. | |
| Applying a distinction. A systemic-constructivist program for qualitative social science research; [Aplicar una distinción. Un programa sistémicoconstructivista para la investigación social cualitativa] | Revista Mad | Urquiza, A.; Billi, M.; Leal, T. | 2017 | Ciudades Resilientes | 10.5354/0719-0527.2017.47269 | https://revistamad.uchile.cl/index.php/RMAD/article/view/47269 | 21-53 | Issue: 37 | 0718-0527 | Thomson Reuters ISI (ESCI) | Spanish | Por lo menos desde el siglo XVIII, el ‘problema de la inducción’, es decir de cómo justificar las abstracciones que se hacen a partir de la observación empírica, ha estado al centro de un encendido debate tanto en la filosofía de la ciencia, como en la praxis de las ciencias sociales. Rechazando las acusaciones de ‘clausura empírica’ levantadas respecto de la Teoría de Sistemas Sociales de Niklas Luhmann, afirmamos por el contrario que esta proporciona una plataforma epistemológica y teórica privilegiada para hacer frente al citado dilema, explicitando las condiciones para producir un razonamiento de tipo ‘abductivo’. Dialogando, por un lado, con la comprensión de Luhmann respecto del conocimiento y de la ciencia, y por el otro, con diversos intentos para aplicar empíricamente la propuesta sistémica e integrarla con otros enfoques analíticos, el presente paper ofrece un modelo general para comprender el rol y la relación de los principios de plausibilidad teórica y fundamentación empírica en la investigación social. A partir de ello, el artículo identifica los criterios de ‘isomorfismo’, ‘perspectivismo’, ‘transparencia’ e ‘iterabilidad’ como indicadores de aceptabilidad científica de una investigación sistémico-constructivista, y ofrece orientaciones para el diseño de un proceso de investigación de este tipo. | |
| Soil respiration and mass balance estimation of fine root production in Fitzroya cupressoides forests of southern Chile | Ecosphere | Urrutia-Jalabert, R.; Malhi, Y.; Lara, A. | 2017 | Servicios Ecosistémicos | 10.1002/ecs2.1640 | http://doi.wiley.com/10.1002/ecs2.1640 | art01640 | Vol: 8 Issue: 4 | 2150-8925 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The soil carbon dynamics of southern hemisphere temperate rainforests have rarely been studied. Here, we report for the first time soil CO2 effluxes and their partitioning for medium-age and old-growth Fitzroya cupressoides forests growing under contrasting environmental conditions in the Coastal Range and Andean Cordillera of southern Chile. Fitzroya is a high biomass and one of the longest lived species in the world. We characterized soil respiration patterns over almost 2 yr. Annual soil respiration was slightly higher in younger forests from the Coastal Range compared with Andean forests during the first studied year (6.37–6.66 vs. 5.06–6.14 Mg C·ha−1·yr−1), and significantly higher during the second year mainly due to a warmer and drier summer (8.08–8.64 vs. 4.98–5.35 Mg C·ha−1·yr−1). Therefore, warmer and drier conditions, likely to become more common in this region under future climate change, were associated with significantly higher respiration in the shallow soils of the coast, but not in the Andes. A higher proportion of autotrophic respiration was found in the Coastal Range forest probably due to a much higher fine root biomass in this site. However, fine root productivity, an important contributor of belowground carbon fluxes, was a little lower (not significantly) in the coastal site (0.81 ± 0.60 vs. 1.50 ± 0.42 Mg C·ha−1·yr−1), indicating a longer root residence time in forests from this area. Soil CO2 effluxes from these forests and their root productivity are at the lower end of values recorded for other mature and old-growth temperate wet forests worldwide. The intrinsic longevity and the particularly poor soils and rainy conditions where these forests grow may influence these facts. Interannual climate variability appears to be especially important for soil respiration in the Coastal Range due to the more Mediterranean climate influence and shallow, poor water retention soils in this area. |
| Wood burning pollution in southern Chile: PM2.5 source apportionment using CMB and molecular markers | Environmental Pollution | Villalobos, A.; Barraza, F.; Jorquera, H.; Schauer, J. | 2017 | Modelación y Sistemas de Observación | 10.1016/j.envpol.2017.02.069 | http://www.sciencedirect.com/science/article/pii/S0269749116324666 | 514-523 | Vol: 225 | 0269-7491 | Thomson Reuters ISI (SCIE) | English | Temuco is a mid-size city representative of severe wood smoke pollution in southern Chile; i.e., ambient 24-h PM2.5 concentrations have exceeded 150 μg/m3 in the winter season and the top concentration reached 372 μg/m3 in 2010. Annual mean concentrations have decreased but are still above 30 μg/m3. For the very first time, a molecular marker source apportionment of ambient organic carbon (OC) and PM2.5 was conducted in Temuco. Primary resolved sources for PM2.5 were wood smoke (37.5%), coal combustion (4.4%), diesel vehicles (3.3%), dust (2.2%) and vegetative detritus (0.7%). Secondary inorganic PM2.5 (sulfates, nitrates and ammonium) contributed 4.8% and unresolved organic aerosols (generated from volatile emissions from incomplete wood combustion), including secondary organic aerosols, contributed 47.1%. Adding the contributions of unresolved organic aerosols to those from primary wood smoke implies that wood burning is responsible for 84.6% of the ambient PM2.5 in Temuco. This predominance of wood smoke is ultimately due to widespread poverty and a lack of efficient household heating methods. The government has been implementing emission abatement policies but achieving compliance with ambient air quality standards for PM2.5 in southern Chile remains a challenge. | |
| The effect of climate change on electricity expenditures in Massachusetts | Energy Policy | Véliz, K.; Kaufmann, R.; Cleveland, C.; Stoner, A. | 2017 | Ciudades Resilientes | 10.1016/j.enpol.2017.03.016 | http://linkinghub.elsevier.com/retrieve/pii/S030142151730157X | 1-11 | Vol: 106 | 0301-4215 | Thomson Reuters ISI (SCIE; SSCI) | English | Climate change affects consumer expenditures by altering the consumption of and price for electricity. Previous analyses focus solely on the former, which implicitly assumes that climate-induced changes in consumption do not affect price. But this assumption is untenable because a shift in demand alters quantity and price at equilibrium. Here we present the first empirical estimates for the effect of climate change on electricity prices. Translated through the merit order dispatch of existing capacity for generating electricity, climate-induced changes in daily and monthly patterns of electricity consumption cause non-linear changes in electricity prices. A 2 °C increase in global mean temperature increases the prices for and consumption of electricity in Massachusetts USA, such that the average household’s annual expenditures on electricity increase by about 12%. Commercial customers incur a 9% increase. These increases are caused largely by higher prices for electricity, whose impacts on expenditures are 1.3 and 3.6 fold larger than changes in residential and commercial consumption, respectively. This suggests that previous empirical studies understate the effects of climate change on electricity expenditures and that policy may be needed to ensure that the market generates investments in peaking capacity to satisfy climate-driven changes in summer-time consumption. | |
| Spatial Distribution of Nitrous Oxide (N2O) in the Reloncaví Estuary–Sound and Adjacent Sea (41°–43° S), Chilean Patagonia | Estuaries and Coasts | Yevenes, M.; Bello, E.; Sanhueza-Guevara, S.; Farías, L. | 2017 | Biogeoquímica | 10.1007/s12237-016-0184-z | http://link.springer.com/10.1007/s12237-016-0184-z | 807-821 | Vol: 40 Issue: 3 | 1559-2723 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Fjords and estuaries exchange large amounts of solutes, gases, and particulates between fluvial and marine systems. These exchanges and their relative distributions of compounds/particles are partially controlled by stratification and water circulation. The spatial and vertical distributions of N2O, an important greenhouse gas, along with other oceanographic variables, are analyzed from the Reloncaví estuary (RE) (~41° 30′ S) to the gulf of Corcovado in the interior sea of Chiloé (43° 45′ S) during the austral winter. Freshwater runoff into the estuary regulated salinity and stratification of the water column, clearly demarking the surface (<5 m depth) and subsurface layer (>5 m depth) and also separating estuarine and marine influenced areas. N2O levels varied between 8.3 and 21 nM (corresponding to 80 and 170 % saturation, respectively), being significantly lower (11.8 ± 1.70) at the surface than in subsurface waters in the Reloncaví estuary (14.5 ± 1.73). Low salinity and NO3 −, NO2 −, and PO4 3− levels, as well as high Si(OH)4 values were associated with low surface N2O levels. Remarkably, an accumulation of N2O was observed in the subsurface waters of the Reloncaví sound, associated with a relatively high consumption of O2. The sound is exposed to increasing anthropogenic impacts from aquaculture and urban discharge, occurring simultaneously with an internal recirculation, which leads to potential signals of early eutrophication. In contrast, within the interior sea of Chiloé (ISC), most of water column was quasi homohaline and occupied by modified subantarctic water (MSAAW), which was relatively rich in N2O (12.6 ± 2.36 nM) and NO3 − (18.3 ± 1.63 μM). The relationship between salinity, nutrients, and N2O revealed that water from the open ocean, entering into ISC (the Gulf of Corcovado) through the Guafo mouth, was the main source of N2O (up to 21 nM), as it gradually mixed with estuarine water. In addition, significant relationships between N2O excess vs. AOU and N2O excess vs. NO3 − suggest that part of N2O is also produced by nitrification. Our results show that the estuarine and marine waters can act as light source or sink of N2O to the atmosphere (air–sea N2O fluxes ranged from −1.57 to 5.75 μmol m−2 day−1), respectively; influxes seem to be associated to brackish water depleted in N2O that also caused a strong stratification, creating a barrier to gas exchange. |
| Temporal and spatial evaluation of satellite-based rainfall estimates across the complex topographical and climatic gradients of Chile | Hydrology and Earth System Sciences | Zambrano-Bigiarini, M.; Nauditt, A.; Birkel, C.; Verbist, K.; Ribbe, L. | 2017 | Dinámica del Clima | 10.5194/hess-21-1295-2017 | http://www.hydrol-earth-syst-sci.net/21/1295/2017/ | 1295-1320 | Vol: 21 Issue: 2 | 1027-5606 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Accurate representation of the real spatio-temporal variability of catchment rainfall inputs is currently severely limited. Moreover, spatially interpolated catchment precipitation is subject to large uncertainties, particularly in developing countries and regions which are difficult to access. Recently, satellite-based rainfall estimates (SREs) provide an unprecedented opportunity for a wide range of hydrological applications, from water resources modelling to monitoring of extreme events such as droughts and floods.This study attempts to exhaustively evaluate – for the first time – the suitability of seven state-of-the-art SRE products (TMPA 3B42v7, CHIRPSv2, CMORPH, PERSIANN-CDR, PERSIAN-CCS-Adj, MSWEPv1.1, and PGFv3) over the complex topography and diverse climatic gradients of Chile. Different temporal scales (daily, monthly, seasonal, annual) are used in a point-to-pixel comparison between precipitation time series measured at 366 stations (from sea level to 4600 m a.s.l. in the Andean Plateau) and the corresponding grid cell of each SRE (rescaled to a 0.25° grid if necessary). The modified Kling–Gupta efficiency was used to identify possible sources of systematic errors in each SRE. In addition, five categorical indices (PC, POD, FAR, ETS, fBIAS) were used to assess the ability of each SRE to correctly identify different precipitation intensities.Results revealed that most SRE products performed better for the humid South (36.4–43.7° S) and Central Chile (32.18–36.4° S), in particular at low- and mid-elevation zones (0–1000 m a.s.l.) compared to the arid northern regions and the Far South. Seasonally, all products performed best during the wet seasons (autumn and winter; MAM–JJA) compared to summer (DJF) and spring (SON). In addition, all SREs were able to correctly identify the occurrence of no-rain events, but they presented a low skill in classifying precipitation intensities during rainy days. Overall, PGFv3 exhibited the best performance everywhere and for all timescales, which can be clearly attributed to its bias-correction procedure using 217 stations from Chile. Good results were also obtained by the research products CHIRPSv2, TMPA 3B42v7 and MSWEPv1.1, while CMORPH, PERSIANN-CDR, and the real-time PERSIANN-CCS-Adj were less skillful in representing observed rainfall. While PGFv3 (currently available up to 2010) might be used in Chile for historical analyses and calibration of hydrological models, the high spatial resolution, low latency and long data records of CHIRPS and TMPA 3B42v7 (in transition to IMERG) show promising potential to be used in meteorological studies and water resource assessments. We finally conclude that despite improvements of most SRE products, a site-specific assessment is still needed before any use in catchment-scale hydrological studies. |
| Physiological and morphological responses to permanent and intermittent waterlogging in seedlings of four evergreen trees of temperate swamp forests | Tree Physiology | Zúñiga-Feest, A.; Bustos-Salazar, A.; Alves, F.; Martinez, V.; Smith-Ramírez, C. | 2017 | Cambio de Uso de Suelo | 10.1093/treephys/tpx023 | https://academic.oup.com/treephys/article/37/6/779/3069384 | 779-789 | Vol: 37 Issue: 6 | 0829-318X, 1758-4469 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Waterlogging decreases a plant's metabolism, stomatal conductance (gs) and photosynthetic rate (A); however, some evergreen species show acclimation to waterlogging. By studying both the physiological and morphological responses to waterlogging, the objective of this study was to assess the acclimation capacity of four swamp forest species that reside in different microhabitats. We proposed that species (Luma apiculata [D.C.] Burret. and Drimys winteri J.R. et G. Forster.) abundant in seasonally and intermittently waterlogged areas (SIWA) would have a higher acclimation capacity than species abundant in the inner swamp (Blepharocalyx cruckshanksii [H et A.] Mied. and Myrceugenia exsucca [D.C.] Berg.) where permanent waterlogging occurs (PWA); it was expected that the species from SIWA would maintain leaf expansion and gas exchange rates during intermittent waterlogging treatments. Conversely, we expected that PWA species would have higher constitutive waterlogging tolerance, and this would be reflected in the formation of lenticels and adventitious roots. Over the course of 2 months, we subjected seedlings to different waterlogging treatments: (i) permanent (sudden, SW), (ii) intermittent (gradual) or (iii) control (field capacity, C). Survival after waterlogging was high (≥80%) for all species and treatments, and only the growth rate of D. winteri subjected to SW was affected. Drimys winteri plants had low, but constant A and g during both waterlogging treatments. Conversely, L. apiculata had the highest A and g values, and g increased significantly during the first several days of waterlogging. In general, seedlings of all species subjected to waterlogging produced more adventitious roots and fully expanded leaves and had higher specific leaf area (SLA) and stomatal density (StD) than seedlings in the C treatment. From the results gathered here, we partially accept our hypothesis as all species showed high tolerance to waterlogging, maintained growth, and had increased A or g during different time points of waterlogging. Differences in leaf (SLA) and stomata functioning (gs, StD) plasticity likely allows plants to maintain positive carbon gains when waterlogging occurs. The species-specific differences found here were not entirely related to microhabitat distribution. |
| A human-scale perspective on global warming: Zero emission year and personal quotes | PloS one | de la Fuente, A.; Rojas, M.; Mac-Lean, C. | 2017 | Modelación y Sistemas de Observación | 10.1371/journal.pone.0179705 | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0179705 | e0179705 | Vol: 12 Issue: 6 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | This article builds on the premise that human consumption of goods, food and transport are the ultimate drivers of climate change. However, the nature of the climate change problem (well described as a tragedy of the commons) makes it difficult for individuals to recognise their personal duty to implement behavioural changes to reduce greenhouse gas emissions. Consequently, this article aims to analyse the climate change issue from a human-scale perspective, in which each of us has a clearly defined personal quota of CO2 emissions that limits our activity and there is a finite time during which CO2 emissions must be eliminated to achieve the “well below 2 °C” warming limit set by the Paris Agreement of 2015 (COP21). Thus, this work’s primary contribution is to connect an equal per capita fairness approach to a global carbon budget, linking personal levels with planetary levels. Here, we show that a personal quota of 5.0 tons of CO 2 yr -1 p -1 is a representative value for both past and future emissions; for this level of a constant per capita emissions and without considering any mitigation, the global accumulated emissions compatible with the “well below 2 °C” and 2 °C targets will be exhausted by 2030 and 2050, respectively. These are references years that provide an order of magnitude of the time that is left to reverse the global warming trend. More realistic scenarios that consider a smooth transition toward a zero-emission world show that the global accumulated emissions compatible with the “well below 2 °C” and 2 °C targets will be exhausted by 2040 and 2080, respectively. Implications of this paper include a return to personal responsibility following equity principles among individuals, and a definition of boundaries to the personal emissions of CO2 . |
| Assessment of quality of input data used to classify ecosystems according to the IUCN Red List methodology: The case of the central Chile hotspot | Biological Conservation | Alaniz, A.; Galleguillos, M.; Perez-Quezada, J. | 2016 | Servicios Ecosistémicos | 10.1016/j.biocon.2016.10.038 | https://www.sciencedirect.com/science/article/pii/S0006320716306954 | 378-385 | Vol: 204 | 0006-3207 | Thomson Reuters ISI (SCIE) | English | During the last decade, the IUCN has developed criteria analogous to the Red List of Threatened Species to perform similar risk assessment on ecosystems, creating the Red List of Ecosystems methodology. One of the most significant challenges for the construction of these lists is the gathering and availability of the information needed to apply the criteria. We present a complement to the IUCN's methodology to assess the threat level to ecosystems, estimating the spatial and temporal quality of the information available in scientific publications. We did this by applying the IUCN criteria to determine the threat level to the sclerophyll ecosystems of central Chile. Spatially explicit studies that identify disturbances in the structure of the vegetation were selected, making it possible to quantify effectively the reduction in the ecosystems' distribution. The spatial and temporal quality of the assessment were estimated as the percentage of the potential ecosystem distribution and the time frame recommended by the IUCN (50 years), that the studies represented for each ecosystem. The application of the methodology allowed the assessment of a high percentage of the ecosystems (85%), which were classified based on the studies with ranges of temporal quality from 30 to 100% and spatial quality from 12 to 100%. If only the assessments with more than medium spatio-temporal quality are considered (> 50%), eight of the 17 evaluated ecosystems are classified in threat categories, which represents 22.9% of the study area. | |
| Regional Sea-Level Change along the Chilean Coast in the 21st century | Journal of Coastal Research | Albrecht, F.; Shaffer, G. | 2016 | Modelación y Sistemas de Observación | 10.2112/JCOASTRES-D-15-00192.1 | http://www.jcronline.org/doi/abs/10.2112/JCOASTRES-D-15-00192.1 | 1322-1332 | Vol: 32 Issue: 6 | 0749-0208 | Thomson Reuters ISI (ESCI) | English | Regional sea-level change for Chile is considered until the end of the 21st century for the RCP4.5 and RCP8.5 scenarios. The main components that contribute to sea-level change are analyzed and summed to achieve a total estimate of sea-level change along the coast of Chile and in the Southeast Pacific. Included are the steric/dynamic component, the contribution from land ice loss and the sea- level change due to the glacial isostatic adjustment. Regional fingerprints and global means are combined to estimate sea-level change in this area. For the steric/dynamic component two different estimates are considered. The results are compared to those found in the IPCC AR5 report. The total mean sea-level rise along the coast lies between 34 cm and 52 cm for the RCP4.5 scenario and between 46 cm and 74 cm for the RCP8.5 scenario, depending on the location and the steric/dynamic component estimate considered. This component is the main contribution in each scenario. All estimates show a modest, relatively constant decrease in sea-level rise along the coast from north to south. | |
| Stakeholder participation in building resilience to disasters in a changing climate | Environmental Hazards | Aldunce, P.; Beilin, R.; Handmer, J.; Howden, M. | 2016 | Dimensión Humana | 10.1080/17477891.2015.1134427 | http://www.tandfonline.com/doi/abs/10.1080/17477891.2015.1134427?journalCode=tenh20 | 58-73 | Vol: 15 Issue: 1 | 1747-7891 | Thomson Reuters ISI (SSCI) | English | The resilience perspective has emerged as a plausible approach to confront the increasingly devastating impacts of disasters; and the challenges and uncertainty climate change poses through an expected rise in frequency and magnitude of hazards. Stakeholder participation is posited as pivotal for building resilience, and resilience is not passive; rather, stakeholders are actively involved in the process of building resilience. Who is involved and how they are involved are crucial aspects for developing resilience in practice. Nevertheless, there are few empirical studies available to inform theory or show how these issues are addressed. This study focuses on revealing how practitioners frame the issue of participation in relation to resilience, its relevance to a changing climate and how, in consequence, they construct practices. Using Hajer's [(1995). The politics of environmental discourse: Ecological modernization and the policy process. New York] ‘Social-interactive discourse theory’, in this... | |
| Unpacking Resilience for Adaptation: Incorporating Practitioners’ Experiences through a Transdisciplinary Approach to the Case of Drought in Chile | Sustainability | Aldunce, P.; Bórquez, R.; Adler, C.; Blanco, G.; Garreaud, R. | 2016 | Dimensión Humana; Dinámica del Clima | 10.3390/su8090905 | http://www.mdpi.com/2071-1050/8/9/905 | art905 | Vol: 8 Issue: 9 | 2071-1050 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | Current debate on the implementation of resilience in addressing climatic impacts calls for more pragmatic means of reducing losses. In this study we aimed to generate context-specific knowledge about resilience factors for addressing the impacts of drought, with the expectation that bringing forth experiential knowledge on how impacts were addressed in the past would shed light on what constitutes key resilience factors for practitioners working in urban contexts. The study was carried in three of the largest cities in Chile: Santiago, Concepción, and Valdivia. The analytical framework consists of urban and regional resilience incorporating transdisciplinary approaches applying the Resilience-Wheel tool, combined with participatory methods for the co-production of knowledge and qualitative content analysis of documents and workshops. Results show that key determinants of building resilience to drought were: improving education and access to information, enhancing preparedness, promoting technology transfer, reinforcing organizational linkages and collaboration, decentralizing governance, and encouraging citizen participation. The Resilience-Wheel was useful for navigating the conceptual complexity and diversity of perspectives inherent among social actors. The transdisciplinary approach allowed us to co-produce key knowledge that can be applied to build resilience in future, through a bottom-up approach that bridges the science–policy interface. |
| Is climate change framed as 'business as usual or as a challenging issue? The practitioners dilemma | Environment and Planning C: Government and Policy | Aldunce, P.; Handmer, J.; Beilin, R.; Howden, M. | 2016 | Dimensión Humana | 10.1177/0263774X15614734 | http://epc.sagepub.com/lookup/doi/10.1177/0263774X15614734 | 999-1019 | Vol: 34 Issue: 5 | 0263-774X | Thomson Reuters ISI (SSCI) | English | There is growing recognition that routine climate change framing is insufficient for addressing the challenges presented by this change, and that different framings of climate change shape stakeholders' practices and guide policy options. This research investigated how stakeholders conceptualise climate change in terms of its seriousness and related uncertainty, and a resilience approach as a possible policy option to confront this uncertainty. An application of the conceptual framework provided by Handmer and Dovers' typology of emergencies is novel to the climate change field. Results show that there is a tendency to frame climate change as complex (with uncertainty representing part of that complexity) and to confront this complexity with less complex policies and solutions. No pattern of a conceptual link between uncertainty and resilience was observed. The results presented in this study offer empirical evidence to inform theory and provide helpful insights to inform policy design and practice. | |
| Informe de devolución Valle del Aconcagua, Primera Parte: Prácticas de adaptación al cambio climático: Sequía | Aldunce, P.; Lillo, G.; Araya, D.; Maldonado, P.; Ramos, I. | 2016 | Agua y Extremos | https://www.cr2.cl/wp-content/uploads/2016/05/devolucion-aconcagua.pdf | 1-15 | Uno de los principales desafíos que enfrenta la sociedad actual es el cambio climático, que ya se comienza a sentir y se proyecta en impactos como el aumento de la temperatura media, derretimiento de nieve y glaciares, cambios en la intensidad y temporalidad de la lluvia, disminución de las reservas de agua dulce superficiales y de la recarga de acuíferos, olas de calor, entre otros1. El Valle del Aconcagua no es ajeno a esta nueva realidad climática y se enfrenta a retos que requieren del trabajo permanente, comprometido e informado de sus habitantes para adaptarse a los efectos del cambio climático, de modo de asegurar el bienestar presente y futuro2. En el presente documento se entregan los resultados del trabajo colectivo realizado con distintos actores sociales del Valle del Aconcagua, respecto de los mecanismos y prácticas desarrolladas para adaptarse a la sequía, así como qué podemos aprender de estas prácticas y cómo podemos fortalecerlas a través del aprendizaje social para aumentar las capacidades adaptativas y de resiliencia. |
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| Dual assimilation of satellite soil moisture to improve streamflow prediction in data-scarce catchments | Water Resources Research | Alvarez-Garreton, C.; Ryu, D.; Western, A.; Crow, W.; Su, C.; Robertson, D. | 2016 | Servicios Ecosistémicos | 10.1002/2015WR018429 | http://onlinelibrary.wiley.com/doi/10.1002/2015WR018429/abstract | 5357-5375 | Vol: 52 Issue: 7 | 0043-1397 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | This paper explores the use of active and passive microwave satellite soil moisture products for improving streamflow prediction within four large (>5000km2) semiarid catchments in Australia. We use the probability distributed model (PDM) under a data-scarce scenario and aim at correcting two key controlling factors in the streamflow generation: the rainfall forcing data and the catchment wetness condition. The soil moisture analysis rainfall tool (SMART) is used to correct a near real-time satellite rainfall product (forcing correction scheme) and an ensemble Kalman filter is used to correct the PDM soil moisture state (state correction scheme). These two schemes are combined in a dual correction scheme and we assess the relative improvements of each. Our results demonstrate that the quality of the satellite rainfall product is improved by SMART during moderate-to-high daily rainfall events, which in turn leads to improved streamflow prediction during high flows. When employed individually, the soil moisture state correction scheme generally outperforms the rainfall correction scheme, especially for low flows. Overall, the combined dual correction scheme further improves the streamflow predictions (reduction in root mean square error and false alarm ratio, and increase in correlation coefficient and Nash-Sutcliffe efficiency). Our results provide new evidence of the value of satellite soil moisture observations within data-scarce regions. We also identify a number of challenges and limitations within the schemes. |
| Fostering a Collaborative Atmospheric Chemistry Research Community in the Latin America and Caribbean Region | Bulletin of the American Meteorological Society | Andrade-Flores, M.; Rojas, N.; Melamed, M.; Mayol-Bracero, O.; Grutter, M.; Dawidowski, L.; Antuña-Marrero, J.; Rudamas, C.; Gallardo, L.; Mamani-Paco, R.; Andrade, M.; Huneeus, N. | 2016 | Modelación y Sistemas de Observación | 10.1175/BAMS-D-14-00267.1 | http://journals.ametsoc.org/doi/10.1175/BAMS-D-14-00267.1 | 1929-1939 | Vol: 97 Issue: 10 | 0003-0007 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | In 2013, the international Commission on Atmospheric Chemistry and Global Pollution (iCACGP) and the International Global Atmospheric Chemistry (IGAC) Project Americas Working Group (iCACGP/IGAC AWG) was formed to build a cohesive network and foster the next generation of atmospheric scientists with the goal of contributing to a scientific community focused on building collective knowledge for the Americas. The Latin America–Caribbean (LAC) region shares common history, culture, and socioeconomic issues but, at the same time, it is highly diverse in its physical and human geography. The LAC region is unique because approximately 80% of its population lives in urban areas, resulting in high-density hotspots of urbanization and vast unpopulated rural areas. In recent years, most countries of the region have experienced rapid growth in population and industrialization as their economies emerge. The rapid urbanization, the associated increases in mobile and industrial sources, and the growth of the agricultural activities related to biomass burning have degraded air quality in certain areas of the LAC region. Air pollution has negative implications for human health, ecosystems, and climate. In addition, air pollution and the warming caused by greenhouse gases could impact the melting of Andean glaciers, an important source of freshwater. To better understand the links between air pollution and climate, it is necessary to increase the number of atmospheric scientists and improve our observational, analytical, and modeling capacities. This requires sustained and prioritized funding as well as stronger collaboration within the LAC region. |
| Derecho internacional y política de adaptación al cambio climático en Reino Unido | OPERA Colombia* | Araya, G. | 2016 | Dimensión Humana | 10.18601/16578651.n19.03 | http://revistas.uexternado.edu.co/index.php/opera/article/view/4737 | 11-34 | Issue: 19 | 1657-8651 | Thomson Reuters ISI (ESCI) | Spanish | Este artículo describe la influencia que ha ejercido el derecho internacional desde las orientaciones provenientes del régimen internacional del cambio climático y la Unión Europea, en la gobernanza actual de la adaptación al cambio climático en el Reino Unido, especialmente en relación con la política del desarrollo sustentable. | |
| Contenidos mínimos y lineamientos metodológicos para la evaluación económica y social de una ley de cambio climático para Chile | Arriagada, R.; Meckievi, S.; Moraga, P.; Vasconi, P. | 2016 | https://www.cr2.cl/wp-content/uploads/2015/08/Contenidos_evaluacion.pdf | 52 | |||||||||
| Extreme temperature and precipitation events in March 2015 in central and northern Chile | Journal of Geophysical Research: Atmospheres | Barrett, B.; Campos, D.; Veloso, J.; Rondanelli, R. | 2016 | Biogeoquímica | 10.1002/2016JD024835 | http://onlinelibrary.wiley.com/doi/10.1002/2016JD024835/abstract | 4563-4580 | Vol: 121 Issue: 9 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | From 18 to 27 March 2015, northern, central, and southern Chile experienced a series of extreme hydrometeorological events. First, the highest surface air temperature ever recorded in Santiago (with reliable records dating to 1877), 36.8°C at Quinta Normal, was measured at 15:47 local time on 20 March 2015. Immediately following this high heat event, an extreme precipitation event, with damaging streamflows from precipitation totals greater than 45 mm, occurred in the semiarid and hyperarid Atacama regions. Finally, concurrent with the heavy precipitation event, extremely warm temperatures were recorded throughout southern Chile. These events were examined from a synoptic perspective with the goal of identifying forcing mechanisms and potential interaction between each analysis which provides operational context by which to identify and predict similar events in the future. Primary findings were as follows: (1) record warm temperatures in central Chile resulted from anomalous lower troposphere ridging and easterly downslope flow, both of which developed in response to an anomalous midtroposphere ridge-trough pattern; (2) a cutoff low with anomalous heights near one standard deviation below normal slowly moved east and was steered ashore near 25°S by circulation around a very strong ridge (anomalies more than 3 standard deviations above normal) centered near 60°S; (3) anomalously high precipitable water content (20 mm above climatological norms) over the Peruvian Bight region was advected southward and eastward ahead of the cutoff low by low-level northwesterly flow, greatly enhancing observed precipitation over northern Chile. |
| Anthropogenic and natural contributions to the Southeast Pacific precipitation decline and recent mega-drought in central Chile | Geophysical Research Letters | Boisier, J.; Rondanelli, R.; Garreaud, R.; Muñoz, F. | 2016 | Biogeoquímica; Dinámica del Clima; Modelación y Sistemas de Observación | 10.1002/2015GL067265 | http://doi.wiley.com/10.1002/2015GL067265 | 413–421 | Vol: 43 Issue: 1 | 0094-8276 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Within large uncertainties in the precipitation response to greenhouse gas forcing, the Southeast Pacific drying stands out as a robust signature within climate models. A precipitation decline, of consistent direction but of larger amplitude than obtained in simulations with historical climate forcing, has been observed in central Chile since the late 1970s. To attribute the causes of this trend, we analyze local rain gauge data and contrast them to a large ensemble of both fully coupled and sea surface temperature-forced simulations. We show that in concomitance with large-scale circulation changes, the Pacific Decadal Oscillation explains about half of the precipitation trend observed in central Chile. The remaining fraction is unlikely to be driven exclusively by natural phenomena but rather consistent with the simulated regional effect of anthropogenic climate change. We particularly estimate that a quarter of the rainfall deficit affecting this region since 2010 is of anthropogenic origin. An increased persistence and recurrence of droughts in central Chile emerges then as a realistic scenario under the current socioeconomic pathway. |
| Impact of warmer eastern tropical Pacific SST on the March 2015 Atacama floods | Monthly Weather Review | Bozkurt, D.; Rondanelli, R.; Garreaud, R.; Arriagada, A. | 2016 | Biogeoquímica; Dinámica del Clima; Modelación y Sistemas de Observación | 10.1175/MWR-D-16-0041.1 | http://journals.ametsoc.org/doi/10.1175/MWR-D-16-0041.1 | 4441-4460 | Vol: 144 Issue: 11 | 0027-0644 | Thomson Reuters ISI (SCIE) | English | Northern Chile hosts the driest place on Earth in the Atacama Desert. Nonetheless, an extreme precipitation event affected the region on 24-26 March 2015 with 1-day accumulated precipitation exceeding 40 mm in several locations and hourly mean rainfall rates higher than 10 mm h−1, producing floods and resulting in casualties and significant damage. The event is analyzed using ERA-Interim reanalysis, surface station data, sounding observations and satellite based radar. Two main conditions favorable for precipitation were present at the time of the event: (i) a cut-off low (COL) off the coast of Northern Chile and (ii) positive sea surface temperature (SST) anomalies over the eastern tropical Pacific. The circulation driven by the COL was strong but not extraordinary. A regional climate model (RegCM4) is used to test the sensitivity of precipitation to SST anomalies by removing the warm SST anomaly in the eastern tropical Pacific. The cooler simulation produced a very similar COL dry dynamics than that simulated in a control run (with observed SST), but, suppressed the precipitation by 60-80% over Northern Chile and 100% in parts of the Atacama Desert due to the decreased availability of precipitable water. The results indicate that the warm SST anomaly over eastern Pacific, favored by the onset of El Niño 2015-2016, was instrumental to the extreme precipitation event by providing an anomalous source of water vapor transported to Atacama by the circulation ahead of the COL. | |
| Climate Services: Lessons Learned and Future Prospects | Earth's Future | Brasseur, G.; Gallardo, L. | 2016 | Modelación y Sistemas de Observación | 10.1002/2015EF000338 | http://onlinelibrary.wiley.com/doi/10.1002/2015EF000338/full | 79-89 | Vol: 4 Issue: 3 | 2328-4277 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | This perspective paper reviews progress made in the last decades to enhance the communication and use of climate information relevant to the political and economic decision process. It focuses, specifically, on the creation and development of climate services, and highlights a number of difficulties that have limited the success of these services. Among them are the insufficient awareness by societal actors of their vulnerability to climate change, the lack of relevant products and services offered by the scientific community, the inappropriate format in which the information is provided, and the inadequate business model adopted by climate services. The authors suggest that, to be effective, centers should host within the same center a diversity of staff including experts in climate science, specialists in impact, adaptation and vulnerability, representatives of the corporate world, agents of the public service as well as social managers and communication specialists. The role and importance of environmental engineering is emphasized. |
| Predicting Vascular Plant Richness in a Heterogeneous Wetland Using Spectral and Textural Features and a Random Forest Algorithm | IEEE Geoscience and Remote Sensing Letters | Cabezas, J.; Galleguillos, M.; Perez-Quezada, J. | 2016 | Servicios Ecosistémicos | 10.1109/LGRS.2016.2532743 | http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=7438775 | 646-650 | Vol: 13 Issue: 5 | 1545-598X | Thomson Reuters ISI (SCIE) | English | A method to predict vascular plant richness using spectral and textural variables in a heterogeneous wetland is presented. Plant richness was measured at 44 sampling plots in a 16-ha anthropogenic peatland. Several spectral indices, first-order statistics (median and standard deviation), and second-order statistics [metrics of a gray-level co-occurrence matrix (GLCM)] were extracted from a Landsat 8 Operational Land Imager image and a Pleiades 1B image. We selected the most important variables for predicting richness using recursive feature elimination and then built a model using random forest regression. The final model was based on only two textural variables obtained from the GLCM and derived from the Landsat 8 image. An accurate predictive capability was reported ( R2=0.6; [Formula: see text]), highlighting the possibility of obtaining parsimonious models using textural variables. In addition, the results showed that the mid-resolution Landsat 8 image provided better predictors of richness than the high-resolution Pleiades image. This is the first study to generate a model for plant richness in a wetland ecosystem. | |
| Climatic responses of Pinus pseudostrobus and Abies religiosa in the Monarch Butterfly Biosphere Reserve, Central Mexico | Dendrochronologia | Carlón Allende, T.; Mendoza, M.; Pérez-Salicrup, D.; Villanueva-Díaz, J.; Lara, A. | 2016 | Servicios Ecosistémicos | 10.1016/j.dendro.2016.04.002 | http://linkinghub.elsevier.com/retrieve/pii/S1125786516300352 | 103-116 | Vol: 38 | 1125-7865 | Thomson Reuters ISI (SCIE) | English | Understanding the effects of climate on the growth of trees is important to project the response of forests to climate change. Dendrochronological analysis offers a “proxy” source for the effects of climatic variation on tree growth at different spatial and temporal scales. To examine influences of temperature and precipitation on radial growth of Pinus pseudostrobus and Abies religiosa, this study combines measurements of radial growth patterns of forest trees in the Monarch Butterfly Biosphere Reserve (MBBR) in central Mexico with temperature and precipitation variables from instrumental records. Dendrochronological samples were collected as cross sections and increment cores by using a chainsaw and increment borers, respectively. Total ring-width chronologies were developed for each site. Principal component analyses (PCA) were used to identify common temperature, precipitation and tree growth variation patterns. Correlation and response function analyses between chronologies and records of temperature and precipitation were used to evaluate the relation of climate variables on tree growth. The months during which tree growth was most strongly affected by precipitation were January, February and October from the previous year; only the temperature of September from the previous year affected the tree growth. In some chronologies, May’s average monthly maximum temperature was negatively correlated with tree growth. PCA and a comparison of PCA factor scores of climatic variables and chronologies showed no significant differences between northern, central or southern portions of the MBBR. Apparently, tree growth in the MBBR is reduced in years of low January–May precipitation combined with high summer (September of the previous year) temperatures, a scenario which is likely to occur as a consequence of global climate change. | |
| Balance de masa glaciar | Revista de geografía Norte Grande | Christie, D. | 2016 | Dinámica del Clima | 10.4067/S0718-34022016000300013 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-34022016000300013&lng=en&nrm=iso&tlng=en | 239-241 | Issue: 65 | 0718-3402 | Thomson Reuters ISI (ESCI) | Spanish | Reseñas de Andrés Rivera; Francisca Bown; Felipe Napoleoni; Camilo Muñoz y Mathias Vüille. Balance de masa glaciar. | |
| The Solar Spectrum in the Atacama Desert | Scientific Reports | Cordero, R.; Damiani, A.; Seckmeyer, G.; Jorquera, J.; Caballero, M.; Rowe, P.; Ferrer, J.; Mubarak, R.; Carrasco, J.; Rondanelli, R.; Matus, M.; Laroze, D. | 2016 | Biogeoquímica | 10.1038/srep22457 | http://www.nature.com/srep/2016/160302/srep22457/full/srep22457.html | art22457 | Vol: 6 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The Atacama Desert has been pointed out as one of the places on earth where the highest surface irradiance may occur. This area is characterized by its high altitude, prevalent cloudless conditions and relatively low columns of ozone and water vapor. Aimed at the characterization of the solar spectrum in the Atacama Desert, we carried out in February-March 2015 ground-based measurements of the spectral irradiance (from the ultraviolet to the near infrared) at seven locations that ranged from the city of Antofagasta (on the southern pacific coastline) to the Chajnantor Plateau (5,100 m altitude). Our spectral measurements allowed us to retrieve the total ozone column, the precipitable water, and the aerosol properties at each location. We found that changes in these parameters, as well as the shorter optical path length at high-altitude locations, lead to significant increases in the surface irradiance with the altitude. Our measurements show that, in the range 0–5100 m altitude, surface irradiance increases with the altitude by about 27% in the infrared range, 6% in the visible range, and 20% in the ultraviolet range. Spectral measurements carried out at the Izaña Observatory (Tenerife, Spain), in Hannover (Germany) and in Santiago (Chile), were used for further comparisons. |
| On the Transport of Urban Pollution in an Andean Mountain Valley | Aerosol and Air Quality Research | Cordova, A.; Arévalo, J.; Marín, J.; Baumgardner, D.; Graciela B. Raga, G.; Pozo, D.; Ochoa, C.; Rondanelli, R. | 2016 | Biogeoquímica | 10.4209/aaqr.2015.05.0371 | http://www.aaqr.org/Doi.php?id=11_AAQR-15-05-SIMtS-0371&v=16&i=3&m=3&y=2016 | 593-605 | Vol: 16 Issue: 3 | 1680-8584 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Urban pollution can often impact surrounding, non-urban regions, through advection and dispersal of pollutants by the prevailing winds. Urban regions located upstream of high mountains, such as the Andes, can potentially impact the cryosphere by deposition of particles onto the surface of the snowpack and glaciers. Santiago, the capital of Chile, has more than 6 million inhabitants and regularly experiences episodes of severe pollution, particularly during the austral winter. Some studies have hypothesized that particle pollution from Santiago can reach the cryosphere downwind of the city, but the scarcity of measurements made high in the mountains prevents the validation of mesoscale models so the proof of actual impact remains elusive. A research project was designed to provide some insight into this question. The Pollution Impact on Snow in the Cordillera - Experiments and Simulations (PISCES) project was carried out in 2014 and includes both observational and modeling components. A five-week field campaign was conducted at the end of winter, at an elevated site in a mountain valley, 65 km to the southeast of the center of Santiago, to characterize some aspects of particulate pollution. During synoptic conditions that result in clear days at the site, the mesoscale mountain-valley circulation is effective in transporting pollutants upwards during the day, leading to diluted particle concentrations beyond the summits of the highest peaks. Cloudy days with reduced up-valley circulation do not show increased concentrations associated with transport. Back trajectories indicate that airmasses reaching the site during the field campaign are seldom influenced by pollution from Santiago. |
| Biogeochemical characteristics of a long-lived anticyclonic eddy in the eastern South Pacific Ocean | Biogeosciences | Cornejo D'Ottone, M.; Bravo, L.; Ramos, M.; Pizarro, O.; Karstensen, J.; Gallegos, M.; Correa-Ramirez, M.; Silva, N.; Farías, L.; Karp-Boss, L. | 2016 | Biogeoquímica | 10.5194/bg-13-2971-2016 | http://www.biogeosciences.net/13/2971/2016/ | 2971-2979 | Vol: 13 Issue: 10 | 1726-4170 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Mesoscale eddies are important, frequent, and persistent features of the circulation in the eastern South Pacific (ESP) Ocean, transporting physical, chemical and biological properties from the productive shelves to the open ocean. Some of these eddies exhibit subsurface hypoxic or suboxic conditions and may serve as important hotspots for nitrogen loss, but little is known about oxygen consumption rates and nitrogen transformation processes associated with these eddies. In the austral fall of 2011, during the Tara Oceans expedition, an intrathermocline, anticyclonic, mesoscale eddy with a suboxic (< 2 µmol kg−1 of O2), subsurface layer (200–400 m) was detected ∼ 900 km off the Chilean shore (30° S, 81° W). The core of the eddy's suboxic layer had a temperature-salinity signature characteristic of Equatorial Subsurface Water (ESSW) that at this latitude is normally restricted to an area near the coast. Measurements of nitrogen species within the eddy revealed undersaturation (below 44 %) of nitrous oxide (N2O) and nitrite accumulation (> 0.5 µM), suggesting that active denitrification occurred in this water mass. Using satellite altimetry, we were able to track the eddy back to its region of formation on the coast of central Chile (36.1° S, 74.6° W). Field studies conducted in Chilean shelf waters close to the time of eddy formation provided estimates of initial O2 and N2O concentrations of the ESSW source water in the eddy. By the time of its offshore sighting, concentrations of both O2 and N2O in the subsurface oxygen minimum zone (OMZ) of the eddy were lower than concentrations in surrounding water and “source water” on the shelf, indicating that these chemical species were consumed as the eddy moved offshore. Estimates of apparent oxygen utilization rates at the OMZ of the eddy ranged from 0.29 to 44 nmol L−1 d−1 and the rate of N2O consumption was 3.92 nmol L−1 d−1. These results show that mesoscale eddies affect open-ocean biogeochemistry in the ESP not only by transporting physical and chemical properties from the coast to the ocean interior but also during advection, local biological consumption of oxygen within an eddy further generates conditions favorable to denitrification and loss of fixed nitrogen from the system. |
| Climate change and the distribution and conservation of the world’s highest elevation woodlands in the South American Altiplano | Global and Planetary Change | Cuyckens, G.; Christie, D.; Domic, A.; Malizia, L.; Renison, D. | 2016 | Dinámica del Clima | 10.1016/j.gloplacha.2015.12.010 | http://www.sciencedirect.com/science/article/pii/S092181 8115301600 | 79–87 | Vol: 137 | 0921-8181 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Climate change is becoming an increasing threat to biodiversity. Consequently, methods for delineation, establishment and management of protected areas must consider the species' future distribution in response to future climate conditions. Biodiversity in high altitude semiarid regions may be particularly threatened by future climate change. In this study we assess the main environmental variables that best explain present day presence of the world's highest elevation woodlands in the South American Altiplano, and model how climate change may affect the future distribution of this unique ecosystem under different climate change scenarios. These woodlands are dominated by Polylepis tarapacana (Rosaceae), a species that forms unique biological communities with important conservation value. Our results indicate that five environmental variables are responsible for 91% and 90.3% of the present and future P. tarapacana distribution models respectively, and suggest that at the end of the 21st century, there will be a significant reduction (56%) in the potential habitat for this species due to more arid conditions. Since it is predicted that P. tarapacana's potential distribution will be severely reduced in the future, we propose a new network of national protected areas across this species distribution range in order to insure the future conservation of this unique ecosystem. Based on an extensive literature review we identify research topics and recommendations for on-ground conservation and management of P. tarapacana woodlands. |
| Human impacts and aridity differentially alter soil N availability in drylands worldwide | Global Ecology and Biogeography | Delgado-Baquerizo, M.; Maestre, F.; Gallardo, A.; Eldridge, D.; Soliveres, S.; Bowker, M.; Prado-Comesaña, A.; Gaitán, J.; Quero, J.; Ochoa, V.; Gozalo, B.; García-Gómez, M.; García-Palacios, P.; Berdugo, M.; Valencia, E.; Escolar, C.; Arredondo, T.; Barraza-Zepeda, C.; Boeken, B.; Bran, D.; Cabrera... | 2016 | Servicios Ecosistémicos | 10.1111/geb.12382 | http://onlinelibrary.wiley.com/doi/10.1111/geb.12382/abstract | 36-45 | Vol: 25 Issue: 1 | 1466-822X | Thomson Reuters ISI (SCIE) | English | Aims Climate and human impacts are changing the nitrogen (N) inputs and losses in terrestrial ecosystems. However, it is largely unknown how these two major drivers of global change will simultaneously influence the N cycle in drylands, the largest terrestrial biome on the planet. We conducted a global observational study to evaluate how aridity and human impacts, together with biotic and abiotic factors, affect key soil variables of the N cycle. Location Two hundred and twenty-four dryland sites from all continents except Antarctica widely differing in their environmental conditions and human influence. Methods Using a standardized field survey, we measured aridity, human impacts (i.e. proxies of land uses and air pollution), key biophysical variables (i.e. soil pH and texture and total plant cover) and six important variables related to N cycling in soils: total N, organic N, ammonium, nitrate, dissolved organic:inorganic N and N mineralization rates. We used structural equation modelling to assess the direct and indirect effects of aridity, human impacts and key biophysical variables on the N cycle. Results Human impacts increased the concentration of total N, while aridity reduced it. The effects of aridity and human impacts on the N cycle were spatially disconnected, which may favour scarcity of N in the most arid areas and promote its accumulation in the least arid areas. Main conclusions We found that increasing aridity and anthropogenic pressure are spatially disconnected in drylands. This implies that while places with low aridity and high human impact accumulate N, most arid sites with the lowest human impacts lose N. Our analyses also provide evidence that both increasing aridity and human impacts may enhance the relative dominance of inorganic N in dryland soils, having a negative impact on key functions and services provided by these ecosystems. |
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| Spatio-temporal analyses of wildfires in the region of Maule, Chile | Bosque | Díaz-Hormazábal, I.; González, M. | 2016 | Servicios Ecosistémicos | 10.4067/S0717-92002016000100014 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-92002016000100014&lng=en&nrm=iso&tlng=en | 147-158 | Vol: 37 Issue: 1 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | Spanish | In the last decades, forest fires have been a concern in different regions of the world, especially by increased occurrences product of human activities and climate changes. In this study the spatio-temporal trends in the occurrence and area affected by fire in the Maule region during the period 1986-2012 were examined. We use the Corporación Nacional Forestal fire database, whose records were spatially represented by a grid of 2x2 km. The occurrence was stable during the analyzed period with an average of 378 events per year. The burned area presented three periods above average with 5.273 hectares per year. Most of the fires affected surfaces of less than 5 hectares, while a very small number of events explain most of the area annually burned in the region. According to the startup fuel, we found an increasing number of events initiated in forest plantations in contrast to the decreasing number of fires originated in the native forests. Causes of fires associated with transit and transportation were the most important. The number of events accidentally caused by burning waste significantly increased in the period studied. Most of the fires occurred in the coastal area and the central valley, strongly associated with the road network and the most populated cities. This work represents an important contribution to the characterization of forest fires in the region of Maule, being the first to represent the fire statistics in Chile in a spatially explicit way. |
| Metagenomic Analysis of the Indian Ocean Picocyanobacterial Community: Structure, Potential Function and Evolution | PloS one | Díez, B.; Nylander, J.; Ininbergs, K.; Dupont, C.; Allen, A.; Yooseph, S.; Rusch, D.; Bergman, B. | 2016 | Biogeoquímica | 10.1371/journal.pone.0155757 | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0155757 | art0155757 | Vol: 11 Issue: 5 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Unicellular cyanobacteria are ubiquitous photoautotrophic microbes that contribute substantially to global primary production. Picocyanobacteria such as Synechococcus and Prochlorococcus depend on chlorophyll a-binding protein complexes to capture light energy. In addition, Synechococcus has accessory pigments organized into phycobilisomes, and Prochlorococcus contains chlorophyll b . Across a surface water transect spanning the sparsely studied tropical Indian Ocean, we examined Synechococcus and Prochlorococcus occurrence, taxonomy and habitat preference in an evolutionary context. Shotgun sequencing of size fractionated microbial communities from 0.1 μm to 20 μm and subsequent phylogenetic analysis indicated that cyanobacteria account for up to 15% of annotated reads, with the genera Prochlorococcus and Synechococcus comprising 90% of the cyanobacterial reads, even in the largest size fraction (3.0–20 mm). Phylogenetic analyses of cyanobacterial light-harvesting genes (chl-binding pcb/isi A, allophycocyanin ( apc AB), phycocyanin ( cpc AB) and phycoerythin ( cpe AB)) mostly identified picocyanobacteria clades comprised of overlapping sequences obtained from Indian Ocean, Atlantic and/or Pacific Oceans samples. Habitat reconstructions coupled with phylogenetic analysis of the Indian Ocean samples suggested that large Synechococcus -like ancestors in coastal waters expanded their ecological niche towards open oligotrophic waters in the Indian Ocean through lineage diversification and associated streamlining of genomes ( e . g . loss of phycobilisomes and acquisition of Chl b ); resulting in contemporary small celled Prochlorococcus . Comparative metagenomic analysis with picocyanobacteria populations in other oceans suggests that this evolutionary scenario may be globally important. |
| Subregional inversion of North African dust sources | Journal of Geophysical Research: Atmospheres | Escribano, J.; Boucher, O.; Chevallier, F.; Huneeus, N. | 2016 | Modelación y Sistemas de Observación | 10.1002/2016JD025020 | http://onlinelibrary.wiley.com/doi/10.1002/2016JD025020/abstract | 8549-8566 | Vol: 121 Issue: 14 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The emission of mineral dust aerosols in arid and semiarid regions is a complex process whose representation in atmospheric models remains crude, due to insufficient knowledge about the aerosol lifting process itself, the lack of global data on soil characteristics, and the impossibility for the models to resolve the fine-scale variability in the wind field that drives some of the dust events. As a result, there are large uncertainties in the total emission flux of mineral dust, its natural variability at various timescales, and the possible contribution from anthropogenic land use changes. This work aims for estimating dust emissions and reduces their uncertainty over the Sahara desert and the Arabian Peninsula—the largest dust source region of the globe. We use a data assimilation approach to constrain dust emission fluxes at a monthly resolution for 18 subregions. The Moderate Resolution Imaging Spectroradiometer satellite-derived aerosol optical depth is assimilated in a regional configuration of a general circulation model coupled to an aerosol model. We describe this data assimilation system and apply it for 1 year, resulting in a total mineral dust emissions flux estimate of 2900 Tg yr−1 over the Sahara desert and the Arabian Peninsula for the year 2006. The analysis field of aerosol optical depth shows an improved fit relative to independent Aerosol Robotic Network measurements as compared to the model prior field. |
| The first twenty years (1994–2014) of ozone soundings from Rapa Nui (27°S, 109°W, 51 m a.s.l.) | Tellus B: Chemical and Physical Meteorology | Gallardo, L.; Henríquez, A.; Thompson, A.; Rondanelli, R.; Carrasco, J.; Orfanoz-Cheuquelaf, A.; Velásquez, P. | 2016 | Biogeoquímica; Modelación y Sistemas de Observación | 10.3402/tellusb.v68.29484 | http://www.tellusb.net/index.php/tellusb/article/view/29484 | art29484 | Vol: 68 Issue: 1 | 0280-6509 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Ozone (O3) soundings have been performed on Easter Island or Rapa Nui (27 °S, 109 °W, 51 m a.s.l.) since 1994 as part of the Global Atmospheric Watch Programme of the World Meteorological Organization. In this work, we analyse 260 soundings compiled over the period 1994–2014, and make the data available for the international community. We characterise O3 profiles over this remote area of the Pacific by means of statistical analyses that consider, on the one hand, a traditional climatology that describes the data in terms of seasonal cycles based on monthly averages and, on the other hand, a process-oriented analysis based on self-organising maps. Our analyses show the influence of both tropical and subtropical/mid-latitude air masses at Rapa Nui. The former occurs in summer and fall when convective conditions prevail, and the latter in late winter and spring when subsiding conditions are recurrent. The occurrence of stratospheric intrusions in late winter and spring in connection with deep troughs and the presence of the subtropical jet stream is also apparent in the data set. The tropospheric ozone column is in good agreement with the corresponding data derived from satellites but with a systematic overestimate of summer and fall values. There is evidence of an upward trend in ozone near the surface, which suggests the impact of local pollution. We look forward to an enhancement of the Rapa Nui observing site, given its location that offers a privileged position to observe climate change over the sparsely sampled and vast South Pacific Ocean. |
| Explorador Climático https://explorador.cr2.cl Centro de Ciencia del Clima y la Resiliencia (CR)² | Garreaud, R.; Bravo, F. | 2016 | 10.13140/RG.2.2.20199.62881 | https://rgdoi.net/10.13140/RG.2.2.20199.62881 | ResearchGate | Spanish | |||||||
| Orographic Precipitation in Coastal Southern Chile: Mean Distribution, Temporal Variability, and Linear Contribution | Journal of Hydrometeorology | Garreaud, R.; Falvey, M.; Montecinos, A. | 2016 | Dinámica del Clima | 10.1175/JHM-D-15-0170.1 | http://journals.ametsoc.org/doi/abs/10.1175/JHM-D-15-0170.1 | 1185-1202 | Vol: 17 Issue: 4 | 1525-755X | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The Nahuelbuta Mountains (NM) are a semielliptical massif 1300 m high in coastal southern Chile (37°–38°S) facing frontal storms that move from the Pacific. Mean precipitation between 900 and 1200 mm yr−1 is observed in the surrounding lowland, but river flow measurements suggest values ≥3000 mm yr−1 atop the mountains. To verify and characterize such marked orographic enhancement, 15 rain gauges were deployed around and over the NM. The observations were supplemented by a high-resolution WRF simulation and linear theory (LT) modeling during the winter of 2011. The estimated mean precipitation increases gradually from offshore (~1000 mm yr−1) to the north-facing foothills (2000 mm yr−1). The precipitation rapidly increases in the upslope sector to reach ~4000 mm yr−1 over the northern half of the NM elevated plateau, and decreases farther south to reach background values 20–30 km downstream of the mountains. The upstream (downstream) orographic enhancement (suppression) was relatively uniform among storms when considering event accumulations but varied substantially within each storm, with larger modifications during pre- and postfrontal stages and minor modifications during the brief but intense frontal passage. WRF results are in good agreement with observations in terms of seasonal and daily mean rainfall distributions, as well as temporal variability. Given its linear, steady-state formulation, the LT model cannot resolve rainfall variability at short (hourly) time scales, which in WRF is at least characterized by transient, mesoscale rainbands. Nonetheless, the rainbands are mobile so the accumulation field at monthly or longer time scales produced by the linear model is remarkably similar to its WRF counterpart. |
| Seed Pubescence and Shape Modulate Adaptive Responses to Fire Cues | PloS one | Gómez-González, S.; Ojeda, F.; Torres-Morales, P.; Palma, J. | 2016 | Servicios Ecosistémicos | 10.1371/journal.pone.0159655 | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0159655 | art0159655 | Vol: 11 Issue: 7 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Post-fire recruitment by seeds is regarded as an adaptive response in fire-prone ecosystems. Nevertheless, little is known about which heritable seed traits are functional to the main signals of fire (heat and smoke), thus having the potential to evolve. Here, we explored whether three seed traits (pubescence, dormancy and shape) and fire regime modulate seed response to fire cues(heat and smoke). As a model study system, we used Helenium aromaticum (Asteraceae), a native annual forb from the Chilean matorral, where fires are anthropogenic. We related seed trait values with fitness responses (germination and survival) after exposure to heat-shock and smoke experimental treatments on seeds from 10 H . aromaticum wild populations. We performed a phenotypic selection experiment to examine the relationship of seed traits with post-treatment fitness within a population (adaptive hypothesis). We then explored whether fire frequency in natural habitats was associated with trait expression across populations, and with germination and survival responses to experimental fire-cues. We found that populations subjected to higher fire frequency had, in average, more rounded and pubescent seeds than populations from rarely burned areas. Populations with more rounded and pubescent seeds were more resistant to 80°C heat-shock and smoke treatments.There was correlated selection on seed traits: pubescent-rounded or glabrouscent-elongated seeds had the highest probability of germinating after heat-shock treatments. Seed pubescence and shape in H . aromaticum are heritable traits that modulate adaptive responses to fire. Our results provide new insights into the process of plant adaptation to fire and highlight the relevance of human-made fires as a strong evolutionary agent in the Anthropocene. |
| Forecasting the northern African dust outbreak towards Europe in April 2011: a model intercomparison | Atmospheric Chemistry and Physics | Huneeus, N.; Basart, S.; Fiedler, S.; Morcrette, J.; Benedetti, A.; Mulcahy, J.; Terradellas, E.; Pérez García-Pando, C.; Pejanovic, G.; Nickovic, S.; Arsenovic, P.; Schulz, M.; Cuevas, E.; Baldasano, J.; Pey, J.; Remy, S.; Cvetkovic, B. | 2016 | Modelación y Sistemas de Observación | 10.5194/acp-16-4967-2016 | http://www.atmos-chem-phys.net/16/4967/2016/ | 4967-4986 | Vol: 16 Issue: 8 | 1680-7316 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In the framework of the World Meteorological Organisation's Sand and Dust Storm Warning Advisory and Assessment System, we evaluated the predictions of five state-of-the-art dust forecast models during an intense Saharan dust outbreak affecting western and northern Europe in April 2011. We assessed the capacity of the models to predict the evolution of the dust cloud with lead times of up to 72 h using observations of aerosol optical depth (AOD) from the AErosol RObotic NETwork (AERONET) and the Moderate Resolution Imaging Spectroradiometer (MODIS) and dust surface concentrations from a ground-based measurement network. In addition, the predicted vertical dust distribution was evaluated with vertical extinction profiles from the Cloud and Aerosol Lidar with Orthogonal Polarization (CALIOP). To assess the diversity in forecast capability among the models, the analysis was extended to wind field (both surface and profile), synoptic conditions, emissions and deposition fluxes. Models predict the onset and evolution of the AOD for all analysed lead times. On average, differences among the models are larger than differences among lead times for each individual model. In spite of large differences in emission and deposition, the models present comparable skill for AOD. In general, models are better in predicting AOD than near-surface dust concentration over the Iberian Peninsula. Models tend to underestimate the long-range transport towards northern Europe. Our analysis suggests that this is partly due to difficulties in simulating the vertical distribution dust and horizontal wind. Differences in the size distribution and wet scavenging efficiency may also account for model diversity in long-range transport. |
| Record-breaking warming and extreme drought in the Amazon rainforest during the course of El Niño 2015–2016 | Scientific Reports | Jiménez-Muñoz, J.; Mattar, C.; Barichivich, J.; Santamaría-Artigas, A.; Takahashi, K.; Malhi, Y.; Sobrino, J.; Schrier, G. | 2016 | Dinámica del Clima | 10.1038/srep33130 | http://www.nature.com/srep/2016/160908/srep33130/full/srep33130.html | art33130 | Vol: 6 | 2045-2322 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The El Niño-Southern Oscillation (ENSO) is the main driver of interannual climate extremes in Amazonia and other tropical regions. The current 2015/2016 EN event was expected to be as strong as the EN of the century in 1997/98, with extreme heat and drought over most of Amazonian rainforests. |
| “Climate change damages”, conceptualization of a legal notion with regard to reparation under international law | Climate Risk Management | Kugler, N.; Moraga Sariego, P. | 2016 | Dimensión Humana | 10.1016/j.crm.2016.06.004 | http://www.sciencedirect.com/science/article/pii/S2212096316300213 | 103-111 | Vol: 13 | 2212-0963 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | The damages related to climate change are a concerning issue for the international community, as no country will escape the impacts of climate change. Indeed, it is a preoccupation for the countries (mostly vulnerable) that will suffer those damages, but also for the States that emitted greenhouse gases which fear to have to repair them. That’s why the international negotiation related to the climate regime use the ambiguous term “loss and damage” to design the impacts related to climate change. The purpose of this article is to know if the term “loss and damage” is a useful one in view of reparation under international law or if it is necessary to conceptualize the “climate change damage” notion employed by the doctrine. More precisely, the central question is the following: why is it necessary to conceptualize the “climate change damage” notion? Even though “loss and damage” could formally be a legal concept, it is substantially useless with regard to reparation under international law because it is too ambiguous. Therefore, we judged necessary to clarify the concept of “climate change damage” used by the doctrine but that unfortunately defines it insufficiently. Indeed, it could be useful for the doctrine but also for the lawyers of vulnerable countries and the judges to dispose of a legal notion in order to consider the reparation of the damages related to climate change under international law. Consequently, we propose in this article a definition of climate change damage that could be useful with regard to reparation under international law. |
| Focusing Conservation Efforts on Ecosystem Service Supply May Increase Vulnerability of Socio-Ecological Systems | PloS one | Laterra, P.; Barral, P.; Carmona, A.; Nahuelhual, L. | 2016 | Dimensión Humana | 10.1371/journal.pone.0155019 | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0155019 | art0155019 | Vol: 11 Issue: 5 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Growing concern about the loss of ecosystem services (ES) promotes their spatial representation as a key tool for the internalization of the ES framework into land use policies. Paradoxically, mapping approaches meant to inform policy decisions focus on the magnitude and spatial distribution of the biophysical supply of ES, largely ignoring the social mechanisms by which these services influence human wellbeing. If social mechanisms affecting ES demand, enhancing it or reducing it, are taken more into account, then policies are more effective. By developing and applying a new mapping routine to two distinct socio-ecological systems, we show a strong spatial uncoupling between ES supply and socio-ecological vulnerability to the loss of ES, under scenarios of land use and cover change. Public policies based on ES supply might not only fail at detecting priority conservation areas for the wellbeing of human societies, but may also increase their vulnerability by neglecting areas of currently low, but highly valued ES supply. |
| Coupled Socio-Environmental Changes Triggered Indigenous Aymara Depopulation of the Semiarid Andes of Tarapacá-Chile during the Late 19th-20th Centuries | PloS one | Lima, M.; Christie, D.; Santoro, M.; Latorre, C. | 2016 | Dinámica del Clima | 10.1371/journal.pone.0160580 | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0160580 | art0160580 | Vol: 11 Issue: 8 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Socio-economic and environmental changes are well known causes of demographic collapse of agrarian cultures. The collapse of human societies is a complex phenomenon where historical and cultural dimensions play a key role, and they may interact with the environmental context. However, the importance of the interaction between socio-economic and climatic factors in explaining possible breakdowns in Native American societies has been poorly explored. The aim of this study is to test the role of socio-economic causes and rainfall variability in the collapse suffered by the Aymara people of the semiarid Andean region of Tarapacá during the period 1820–1970. Our motivation is to demonstrate that simple population dynamic models can be helpful in understanding the causes and relative importance of population changes in Andean agro-pastoral societies in responses to socio-environmental variability. Simple logistic models that combine the effects of external socio-economic causes and past rainfall variability (inferred from Gross Domestic Product [GDP] and tree-rings, respectively) were quite accurate in predicting the sustained population decline of the Aymara people. Our results suggest that the depopulation in the semiarid Tarapacá province was caused by the interaction among external socio-economic pressures given by the economic growth of the lowlands and demands for labor coupled with a persistent decline in rainfall. This study constitutes an example of how applied ecological knowledge, in particular the application of the logistic equation and theories pertaining to nonlinear population dynamics and exogenous perturbations, can be used to better understand major demographic changes in human societies. |
| Comparing Generalized Linear Models and random forest to model vascular plant species richness using LiDAR data in a natural forest in central Chile | Remote Sensing of Environment | Lopatin, J.; Dolos, K.; Hernández, H.; Galleguillos, M.; Fassnacht, F. | 2016 | Servicios Ecosistémicos | 10.1016/j.rse.2015.11.029 | http://linkinghub.elsevier.com/retrieve/pii/S0034425715302169 http://www.sciencedirect.com/science/article/pii/S0034425715302169 | 200–210 | Vol: 173 | 0034-4257 | Thomson Reuters ISI (SCIE) | English | Biodiversity is considered to be an essential element of the Earth system, driving important ecosystem services. However, the conservation of biodiversity in a quickly changingworld is a challenging task which requires cost- efficient and precise monitoring systems. In the present study, the suitability of airborne discrete-return LiDAR data for the mapping of vascular plant species richness within a Sub-Mediterranean second growth native forest ecosystemwas examined. The vascular plant richness of four different layers (total, tree, shrub andherb richness) was modeled using twelve LiDAR-derived variables. As species richness values are typically count data, the cor- responding asymmetry and heteroscedasticity in the error distribution has to be considered. In this context,we compared the suitability of randomforest (RF) and a Generalized Linear Model (GLM)with a negative binomial error distribution. Both models were coupled with a feature selection approach to identify the most relevant LiDAR predictors and keep the models parsimonious. The results of RF and GLM agreed that the three most im- portant predictors for all four layers were altitude above sea level, standard deviation of slope and mean canopy height. Thiswas consistent with the preconception of LiDAR's suitability for estimating species richness,which is its capacity to capture three types of information: micro-topographical, macro-topographical and canopy struc- tural. Generalized LinearModels showed higher performances (r2: 0.66, 0.50, 0.52, 0.50; nRMSE: 16.29%, 19.08%, 17.89%, 21.31% for total, tree, shrub and herb richness respectively) than RF (r2: 0.55, 0.33, 0.45, 0.46; nRMSE: 18.30%, 21.90%, 18.95%, 21.00% for total, tree, shrub and herb richness, respectively). Furthermore, the results of the best GLMweremore parsimonious (three predictors) and less biased than the best RFmodels (twelve pre- dictors). We think that this is due to the mentioned non-symmetric error distribution of the species richness values, which RF is unable to properly capture. Fromanecological perspective, thepredicted patterns agreedwell with theknown vegetationcomposition of the area. We found especially high species numbers at low elevations and along riversides. In these areas, overlap- ping distributions of thermopile sclerophyllos species,water demanding Valdivian evergreen species and species growing in Nothofagus obliqua forests occur. The three main conclusions of the study are: 1) appropriatemodel selection is crucialwhenworkingwith biodiver- sitycountdata; 2) the applicationofRFfordatawithnon-symmetricerrordistributions isquestionable; and3) struc- tural and topographic information derived fromLiDAR data is useful for predicting local plant species richness. © | |
| Reconstructing the annual mass balance of the Echaurren Norte glacier (Central Andes, 33.5° S) using local and regional hydroclimatic data | The Cryosphere | Masiokas, M.; Christie, D.; Le Quesne, C.; Pitte, P.; Ruiz, L.; Villalba, R.; Luckman, B.; Berthier, E.; Nussbaumer, S.; González-Reyes, Á.; McPhee, J.; Barcaza, G. | 2016 | Dinámica del Clima | 10.5194/tc-10-927-2016 | http://www.the-cryosphere.net/10/927/2016/ | 927-940 | Vol: 10 Issue: 2 | 1994-0416 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Despite the great number and variety of glaciers in southern South America, in situ glacier mass-balance records are extremely scarce and glacier–climate relationships are still poorly understood in this region. Here we use the longest (> 35 years) and most complete in situ mass-balance record, available for the Echaurren Norte glacier (ECH) in the Andes at ∼ 33.5° S, to develop a minimal glacier surface mass-balance model that relies on nearby monthly precipitation and air temperature data as forcing. This basic model is able to explain 78 % of the variance in the annual glacier mass-balance record over the 1978–2013 calibration period. An attribution assessment identified precipitation variability as the dominant forcing modulating annual mass balances at ECH, with temperature variations likely playing a secondary role. A regionally averaged series of mean annual streamflow records from both sides of the Andes between ∼ 30 and 37° S is then used to estimate, through simple linear regression, this glacier's annual mass-balance variations since 1909. The reconstruction model captures 68 % of the observed glacier mass-balance variability and shows three periods of sustained positive mass balances embedded in an overall negative trend over the past 105 years. The three periods of sustained positive mass balances (centered in the 1920s–1930s, in the 1980s and in the first decade of the 21st century) coincide with several documented glacier advances in this region. Similar trends observed in other shorter glacier mass-balance series suggest that the Echaurren Norte glacier reconstruction is representative of larger-scale conditions and could be useful for more detailed glaciological, hydrological and climatological assessments in this portion of the Andes. |
| Effects of light and phosphorus on summer DMS dynamics in subtropical waters using a global ocean biogeochemical model | Environmental Chemistry | Masotti, I.; Belviso, S.; Bopp, L.; Tagliabue, A.; Bucciarelli, E. | 2016 | Biogeoquímica | 10.1071/EN14265 | http://www.publish.csiro.au/paper/EN14265.htm | 379-389 | Vol: 13 Issue: 2 | 1448-2517 | Thomson Reuters ISI (SCIE) | English | The occurrence of a summer DMS paradox in the vast subtropical gyres is a strong matter of debate because approaches using discrete measurements, climatological data and model simulations yielded contradictory results. The major conclusion of the first appraisal of prognostic ocean DMS models was that such models need to give more weight to the direct effect of environmental forcings (e.g. irradiance) on DMS dynamics to decouple them from ecological processes. Here, the relative role of light and phosphorus on summer DMS dynamics in subtropical waters is assessed using the ocean general circulation and biogeochemistry model NEMO-PISCES in which macronutrient concentrations were restored to monthly climatological data values to improve the representation of phosphate concentrations. Results show that the vertical and temporal decoupling between chlorophyll and DMS concentrations observed in the Sargasso Sea during the summer months is captured by the model. Additional sensitivity tests show that the simulated control of phosphorus on surface DMS concentrations in the Sargasso Sea is much more important than that of light. By extending the analysis to the whole North Atlantic Ocean, we show that the longitudinal distribution of DMS during summer is asymmetrical and that a correlation between the solar radiation dose and DMS concentrations only occurs in the Sargasso Sea. The lack of a widespread summer DMS paradox in our model simulation as well as in the comparison of discrete and climatological data could be due to the limited occurrence of phosphorus limitation in the global ocean. | |
| Fixed-points in random Boolean networks: The impact of parallelism in the Barabási–Albert scale-free topology case | Biosystems | Moisset de Espanés, P.; Osses, A.; Rapaport, I. | 2016 | Modelación y Sistemas de Observación | 10.1016/j.biosystems.2016.10.003 | https://www.sciencedirect.com/science/article/pii/S0303264716302520 | 167-176 | Vol: 150 | 0303-2647 | Thomson Reuters ISI (SCIE) | English | Fixed points are fundamental states in any dynamical system. In the case of gene regulatory networks (GRNs) they correspond to stable genes profiles associated to the various cell types. We use Kauffman's approach to model GRNs with random Boolean networks (RBNs). In this paper we explore how the topology affects the distribution of the number of fixed points in randomly generated networks. We also study the size of the basins of attraction of these fixed points if we assume the α-asynchronous dynamics (where every node is updated independently with probability 0 ≤ α ≤ 1). It is well-known that asynchrony avoids the cyclic attractors into which parallel dynamics tends to fall. We observe the remarkable property that, in all our simulations, if for a given RBN with Barabási–Albert topology and α-asynchronous dynamics an initial configuration reaches a fixed point, then every configuration also reaches a fixed point. By contrast, in the parallel regime, the percentage of initial configurations reaching a fixed point (for the same networks) is dramatically smaller. We contrast the results of the simulations on Barabási–Albert networks with the classical Erdös–Rényi model of random networks. Everything indicates that Barabási–Albert networks are extremely robust. Finally, we study the mean and maximum time/work needed to reach a fixed point when starting from randomly chosen initial configurations. | |
| Variation in coastal Antarctic microbial community composition at sub-mesoscale: spatial distance or environmental filtering? | FEMS Microbiology Ecology | Moreno-Pino, M.; Iglesia, R.; Valdivia, N.; Henríquez-Castilo, C.; Galán, A.; Díez, B.; Trefault, N. | 2016 | Biogeoquímica | 10.1093/femsec/fiw088 | http://femsec.oxfordjournals.org/content/92/7/fiw088 | fiw088 | Vol: 92 Issue: 7 | 0168-6496 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Spatial environmental heterogeneity influences diversity of organisms at different scales. Environmental filtering suggests that local environmental conditions provide habitat-specific scenarios for niche requirements, ultimately determining the composition of local communities. In this work, we analyze the spatial variation of microbial communities across environmental gradients of sea surface temperature, salinity and photosynthetically active radiation and spatial distance in Fildes Bay, King George Island, Antarctica. We hypothesize that environmental filters are the main control of the spatial variation of these communities. Thus, strong relationships between community composition and environmental variation and weak relationships between community composition and spatial distance are expected. Combining physical characterization of the water column, cell counts by flow cytometry, small ribosomal subunit genes fingerprinting and next generation sequencing, we contrast the abundance and composition of photosynthetic eukaryotes and heterotrophic bacterial local communities at a submesoscale. Our results indicate that the strength of the environmental controls differed markedly between eukaryotes and bacterial communities. Whereas eukaryotic photosynthetic assemblages responded weakly to environmental variability, bacteria respond promptly to fine-scale environmental changes in this polar marine system. |
| Streamflow variability in the Chilean Temperate-Mediterranean climate transition (35°S–42°S) during the last 400 years inferred from tree-ring records | Climate Dynamics | Munoz, A.; Gonzalez-Reyes, A.; Lara, A.; Sauchyn, D.; Christie, D.; Villalba, R.; Isabella, A.; Urrutia-Jalabert, R.; Mundo, I.; Szejner, P.; Puchi, P.; Toledo, I.; Le Quesne, C.; Vanstone, J.; Stahle, D.; Sheppard, P. | 2016 | Dinámica del Clima; Servicios Ecosistémicos | 10.1007/s00382-016-3068-9 | http://link.springer.com/article/10.1007%2Fs00382-016-3068-9 | 4051-4066 | Vol: 47 Issue: 12 | 0930-7575 | Thomson Reuters ISI (SCIE) | English | As rainfall in South-Central Chile has decreased in recent decades, local communities and industries have developed an understandable concern about their threatened water supply. Reconstructing streamflows from tree-ring data has been recognized as a useful paleoclimatic tool in providing long-term perspectives on the temporal characteristics of hydroclimate systems. Multi-century long streamflow reconstructions can be compared to relatively short instrumental observations in order to analyze the frequency of low and high water availability through time. In this work, we have developed a Biobío River streamflow reconstruction to explore the long-term hydroclimate variability at the confluence of the Mediterranean-subtropical and the Temperate-humid climate zones, two regions represented by previous reconstructions of the Maule and Puelo Rivers, respectively. In a suite of analyses, the Biobío River reconstruction proves to be more similar to the Puelo River than the Maule River, despite its closer geographic proximity to the latter. This finding corroborates other studies with instrumental data that identify 37.5°S as a latitudinal confluence of two climate zones. The analyzed rivers are affected by climate forcings on interannual and interdecadal time-scales, Tropical (El Niño Southern Oscillation; ENSO) and Antarctic (Southern Annular Mode; SAM). Longer cycles found, around 80-years, are well correlated only with SAM variation, which explains most of the variance in the Biobío and Puelo rivers. This cycle also has been attributed to orbital forcing by other authors. All three rivers showed an increase in the frequency of extreme high and low flow events in the 20th century. The most extreme dry and wet years in the instrumental record (1943-2000) were not the most extreme of the past 400-years reconstructed for the three rivers (1600-2000), yet both instrumental record years did rank in the five most extreme of the streamflow reconstructions as a whole. These findings suggest a high level of natural variability in the hydro-climatic conditions of the region, where extremes characterized the 20th century. This information is particularly useful when evaluating and improving a wide variety of water management models that apply to water resources that are sensitive to agricultural and hydropower industries. | |
| Conocimiento Climático y Redes de Datos Meteorológicos ¿Por qué necesitamos monitorear el clima? | Bits de Ciencias (DCC-UCH) | Muñoz, F. | 2016 | Modelación y Sistemas de Observación | https://www.dcc.uchile.cl/Bitsdeciencia14.pdf | 35-41 | Issue: 14 | 0718-8005 | El tiempo y el clima afectan la forma en que vivimos y las decisiones que tomamos. La disponibilidad hídrica, actividades económicas, interacciones sociales, migraciones, planificación e implementación de políticas públicas a diferentes escalas, e incluso la biodiversidad del planeta se relacionan con las tendencias climáticas o con la recurrencia de eventos extremos y los escenarios futuros. A nivel global, eventos meteorológicos extremos tales como sequías, tormentas de viento, olas de calor, inundaciones fluviales y costeras han aumentado considerablemente en las últimas décadas (ver Jennings 2011), y las proyecciones climáticas (IPCC, 2014) muestran que estos serán más frecuentes y severos. En nuestro país, por ejemplo, la sequía extrema y los aumentos de temperatura que hemos experimentado en los últimos seis años no tienen precedentes en el registro histórico. Esta condición se presenta en siete regiones con un déficit de precipitaciones cercano al 30% y en el contexto de la década más seca y cálida de los últimos 100 años. Pero, ¿cómo podemos realizar predicciones a largo plazo y así determinar la eventual recurrencia de algún evento, diferenciando la contribución antropogénica de la variabilidad natural? Sólo es posible si contamos con datos observados de larga data, robustos y confiables que sirvan de entrada a los modelos climáticos. En tanto, para predecir y generar alertas tempranas de eventos extremos –como aluviones, in-cendios forestales derivados de olas de calor, o tormentas inusuales– es también necesario contar con redes automáticas de monitoreo que recolecten, procesen y modelen estas observaciones en tiempo real. |
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| Coastal Clouds at the Eastern Margin of the Southeast Pacific: Climatology and Trends | Journal of Climate | Muñoz, R.; Quintana, J.; Falvey, M.; Rutllant, J.; Garreaud, R. | 2016 | Dinámica del Clima | 10.1175/JCLI-D-15-0757.1 | http://journals.ametsoc.org/doi/10.1175/JCLI-D-15-0757.1 | 4525-4542 | Vol: 29 Issue: 12 | 0894-8755 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The climatology and recent trends of low-level coastal clouds at three sites along the northern Chilean coast (18.3°–23.4°S) are documented based upon up to 45 years of hourly observations of cloud type, coverage, and heights. Consistent with the subtropical location, cloud types are dominated by stratocumuli having greatest coverage (>7 oktas) and smaller heights (600–750 m) during the nighttime of austral winter and spring. Meridionally, nighttime cloud fraction and cloud-base heights increase from south to north. Long-term trends in mean cloud cover are observed at all sites albeit with a seasonal modulation, with increasing (decreasing) coverage in the spring (fall). Consistent trend patterns are also observed in independent sunshine hour measurements at the same sites. Cloud heights show negative trends of about 100 m decade−1 (1995–2010), although the onset time of this tendency differs between sites. The positive cloud fraction trends during the cloudy season reported here disagree with previous studies, with discrepancies attributed to differences in datasets used or to methodological differences in data analysis. The cloud-base height tendency, together with a less rapid lowering of the subsidence inversion base height, suggests a deepening of the coastal cloud layer. While consistent with the tendency toward greater low-level cloud cover and the known cooling of the marine boundary layer in this region, these tendencies are at odds with a drying trend of the near-surface air documented here as well. Assessing whether this intriguing result is caused by physical factors or by limitations of the data demands more detailed observations, some of which are currently under way. |
| Mapping social values of ecosystem services: What is behind the map? | Ecology and Society | Nahuelhual, L.; Benra Ochoa, F.; Rojas, F.; Díaz, G.; Carmona, A. | 2016 | Dimensión Humana | 10.5751/ES-08676-210324 | http://www.ecologyandsociety.org/vol21/iss3/art24/ | art24 | Vol: 21 Issue: 3 | 1708-3087 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Gold Open Access | English | A growing interest in mapping the social value of ecosystem services (ES) is not yet methodologically aligned with what is actually being mapped. We critically examine aspects of the social value mapping process that might influence map outcomes and limit their practical use in decision making. We rely on an empirical case of participatory mapping, for a single ES (recreation opportunities), which involves diverse stakeholders such as planners, researchers, and community representatives. Value elicitation relied on an individual open-ended interview and a mapping exercise. Interpretation of the narratives and GIS calculations of proximity, centrality, and dispersion helped in exploring the factors driving participants’ answers. Narratives reveal diverse value types. Whereas planners highlighted utilitarian and aesthetic values, the answers from researchers revealed naturalistic values as well. In turn community representatives acknowledged symbolic values. When remitted to the map, these values were constrained to statements toward a much narrower set of features of the physical (e.g., volcanoes) and built landscape (e.g., roads). The results suggest that mapping, as an instrumental approach toward social valuation, may capture only a subset of relevant assigned values. This outcome is the interplay between participants’ characteristics, including their acquaintance with the territory and their ability with maps, and the mapping procedure itself, including the proxies used to represent the ES and the value typology chosen, the elicitation question, the cartographic features displayed on the base map, and the spatial scale. |
| Monitoring global drought using the self-calibrating Palmer Drought Severity Index | State of the Climate 2015, Bulletin of the American Meteorological Society | Osborn, T.; Barichivich, J.; Harris, I.; van der Schrier, G.; Jones, P. | 2016 | Servicios Ecosistémicos | 10.1175/2016BAMSStateoftheClimate.1 | http://journals.ametsoc.org/doi/10.1175/2016BAMSStateoftheClimate.1 | S32-S36 | Vol: 97 Issue: 8 | 0003-0007 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Chapter 2. GLOBAL CLIMATE, Section 9. Monitoring global drought using the self-calibrating Palmer drought severity index. |
| South Pacific Integrated Ecosystem Studies meeting: toward conservation and sustainable use of marine resources in the South Pacific | Fisheries Oceanography | Parada, C.; Frusher, S.; Bustamante, R.; Di Lorenzo, E.; Bernal, P.; Cryer, M.; Dunn, A.; Garreaud, R.; Gutierrez, M.; Jennings, S.; Montecinos, A.; Neira, S.; Quiñones, R.; Takahashi, K.; Tascheri, R.; Yannicelli, B. | 2016 | Dinámica del Clima | 10.1111/fog.12148 | http://doi.wiley.com/10.1111/fog.12148 | 1-4 | Vol: 25 | 1054-6006 | Thomson Reuters ISI (SCIE) | English | The South Pacific region represents the world's largest oceanic water mass and plays a significant role in the earth's climate systems. This region also contains the largest group of island nations, most of whom are dependent on marine resources for their livelihoods. Several of the largest coastal and oceanic gisheries also occur in this region (FAO, 2014). In addition, for the countries associated with the southern Pacific Ocean region, the sea provides significant social, cultural and economic benefits, with many countries being heavily reliant on both coastal and oceanic marine resources (Bell et al., 2013). Increasing coastal populations and climate change are expected to augment human demands on already fully exploited or over-exploited marine resources, threatening both food security and sustainable livelihoods (Bell et al. 2011). Therefore, its imperative that the science that describes and predicts linked biophysical and human systems is understood and developed to meet these needs. Climate change will have many impacts on marine ecosystems, with implications for end users including individuals, local communities, industries and governments. Improved scientific support for policy and management decision-making in the face of these potential impacts is essential. | |
| How many measurements are needed to estimate accurate daily and annual soil respiration fluxes? Analysis using data from a temperate rainforest | Biogeosciences | Perez-Quezada, J.; Brito, C.; Cabezas, J.; Galleguillos, M.; Fuentes, J.; Bown, H.; Franck, N. | 2016 | Servicios Ecosistémicos | 10.5194/bg-13-6599-2016 | http://www.biogeosciences.net/13/6599/2016/ | 6599-6609 | Vol: 13 Issue: 24 | 1726-4170 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Making accurate estimations of daily and annual Rs fluxes is key for understanding the carbon cycle process and projecting effects of climate change. In this study we used high-frequency sampling (24 measurements per day) of Rs in a temperate rainforest during 1 year, with the objective of answering the questions of when and how often measurements should be made to obtain accurate estimations of daily and annual Rs. We randomly selected data to simulate samplings of 1, 2, 4 or 6 measurements per day (distributed either during the whole day or only during daytime), combined with 4, 6, 12, 26 or 52 measurements per year. Based on the comparison of partial-data series with the full-data series, we estimated the performance of different partial sampling strategies based on bias, precision and accuracy. In the case of annual Rs estimation, we compared the performance of interpolation vs. using non-linear modelling based on soil temperature. The results show that, under our study conditions, sampling twice a day was enough to accurately estimate daily Rs (RMSE < 10 % of average daily flux), even if both measurements were done during daytime. The highest reduction in RMSE for the estimation of annual Rs was achieved when increasing from four to six measurements per year, but reductions were still relevant when further increasing the frequency of sampling. We found that increasing the number of field campaigns was more effective than increasing the number of measurements per day, provided a minimum of two measurements per day was used. Including night-time measurements significantly reduced the bias and was relevant in reducing the number of field campaigns when a lower level of acceptable error (RMSE < 5 %) was established. Using non-linear modelling instead of linear interpolation did improve the estimation of annual Rs, but not as expected. In conclusion, given that most of the studies of Rs use manual sampling techniques and apply only one measurement per day, we suggest performing an intensive sampling at the beginning of the study to determine minimum daily and annual frequencies of sampling. |
| The South American monsoon variability over the last millennium in climate models | Climate of the Past | Rojas, M.; Arias, P.; Flores-Aqueveque, V.; Seth, A.; Vuille, M. | 2016 | Modelación y Sistemas de Observación | 10.5194/cp-12-1681-2016 | http://www.clim-past.net/12/1681/2016/ | 1681-1691 | Vol: 12 Issue: 8 | 1814-9324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In this paper we assess South American monsoon system (SAMS) variability in the last millennium as depicted by global coupled climate model simulations. High-resolution proxy records for the South American monsoon over this period show a coherent regional picture of a weak monsoon during the Medieval Climate Anomaly and a stronger monsoon during the Little Ice Age (LIA). Due to the small external forcing during the past 1000 years, model simulations do not show very strong temperature anomalies over these two specific periods, which in turn do not translate into clear precipitation anomalies, in contrast with the rainfall reconstructions in South America. Therefore, we used an ad hoc definition of these two periods for each model simulation in order to account for model-specific signals. Thereby, several coherent large-scale atmospheric circulation anomalies are identified. The models feature a stronger monsoon during the LIA associated with (i) an enhancement of the rising motion in the SAMS domain in austral summer; (ii) a stronger monsoon-related upper-tropospheric anticyclone; (iii) activation of the South American dipole, which results in a poleward shift of the South Atlantic Convergence Zone; and (iv) a weaker upper-level subtropical jet over South America. The diagnosed changes provide important insights into the mechanisms of these climate anomalies over South America during the past millennium. |
| Radiocarbon constraints on the extent and evolution of the South Pacific glacial carbon pool | Nature Communications | Ronge, T.; Tiedemann, R.; Lamy, F.; Köhler, P.; Alloway, B.; De Pol-Holz, R.; Pahnke, K.; Southon, J.; Wacker, L. | 2016 | Biogeoquímica | 10.1038/ncomms11487 | http://www.nature.com/ncomms/2016/160509/ncomms11487/full/ncomms11487.html | art11487 | Vol: 7 | 2041-1723 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | During the last deglaciation, the opposing patterns of atmospheric CO2 and radiocarbon activities (Δ14C) suggest the release of 14C-depleted CO2 from old carbon reservoirs. Although evidences point to the deep Pacific as a major reservoir of this 14C-depleted carbon, its extent and evolution still need to be constrained. Here we use sediment cores retrieved along a South Pacific transect to reconstruct the spatio-temporal evolution of Δ14C over the last 30,000 years. In ~2,500–3,600 m water depth, we find 14C-depleted deep waters with a maximum glacial offset to atmospheric 14C (ΔΔ14C=−1,000‰). Using a box model, we test the hypothesis that these low values might have been caused by an interaction of aging and hydrothermal CO2 influx. We observe a rejuvenation of circumpolar deep waters synchronous and potentially contributing to the initial deglacial rise in atmospheric CO2. These findings constrain parts of the glacial carbon pool to the deep South Pacific. |
| Air quality forecasting for winter-time PM 2.5 episodes occurring in multiple cities in central and southern Chile | Journal of Geophysical Research: Atmospheres | Saide, P.; Mena-Carrasco, M.; Tolvett, S.; Hernandez, P.; Carmichael, G. | 2016 | Modelación y Sistemas de Observación | 10.1002/2015JD023949 | http://doi.wiley.com/10.1002/2015JD023949 | 558-575 | Vol: 121 Issue: 1 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Episodic air quality degradation due to particles occurs in multiple cities in central and southern Chile during the austral winter reaching levels up to 300–800 µg/m3 hourly PM2.5, which can be associated with severe effects on human health. An air quality prediction system is developed to predict such events in near real time up to 3 days in advance for nine cities with regular air quality monitoring: Santiago, Rancagua, Curicó, Talca, Chillan, Los Ángeles, Temuco, Valdivia, and Osorno. The system uses the Weather Research and Forecasting with Chemistry model configured with a nested 2 km grid-spacing domain to predict weather and inert tracers. The tracers are converted to hourly PM2.5 concentrations using an observationally based calibration which is substantially less computationally intensive than a full chemistry model. The conversion takes into account processes occurring in these cities, including higher likelihood of episode occurrence during weekends and during colder days, the latter related to increased wood-burning-stove activity for heating. The system is calibrated and evaluated for April–August 2014 where it has an overall skill of 53–72% of episodes accurately forecasted (61–76% for the best initialization) which is better than persistence for most stations. Forecasts one, two, and three days in advance all have skill in forecasting events but often present large variability within them due to different meteorological initializations. The system is being implemented in Chile to assist authority decisions not only to warn the population but also to take contingency-based emission restrictions to try to avoid severe pollution events. |
| ¿Ocupaciones tardías del Complejo Cultural Bato en Maitencillo? Implicancias para la trayectoria histórica de las poblaciones del litoral de Chile Central | Boletín de la Sociedad Chilena de Arqueología | Salazar, D.; Corral, I.; Corrales, P.; Avilés, S.; Escudero, A.; Estévez, D.; Flores, C.; Oyarzo, C.; Palma, C. | 2016 | Biogeoquímica | https://boletin.scha.cl/boletin/index.php/boletin/article/view/567 | 46-69 | Vol: 46 | 0716-5730 | Latindex | Se discute la existencia y características de ocupaciones posiblemente correspondientes al Complejo Cultural Bato en la costa de Maitencillo, a inicios del segundo milenio de nuestra era. Los datos provienen de excavaciones de rescate en los sitios Abanico 1 y Abanico 3, así como del análisis de sus materiales y contextos. Ambos sitios serían conchales efímeros con ocupaciones del Período Alfarero Temprano datadas entre los siglos XII y XIV, además de una ocupación histórica temprana en Abanico 3. Los resultados sugieren la posibilidad de que formas de vida tradicionales, originadas en el PAT de Chile Central, se mantengan en ciertos sectores hasta tiempos prehispánicos tardíos e incluso históricos tempranos, abriendo interesantes interrogantes acerca de las condiciones de coexistencia de estas poblaciones con otras sociedades más complejas tales como la Cultura Aconcagua, el Tawantinsuyu y el imperio hispano colonial. | |||
| Hydrologic control of carbon cycling and aged carbon discharge in the Congo River basin | Nature Geoscience | Schefuß, E.; Eglinton, T.; Spencer-Jones, C.; Rullkötter, J.; De Pol-Holz, R.; Talbot, H.; Grootes, P.; Schneider, R. | 2016 | Biogeoquímica | 10.1038/ngeo2778 | http://www.nature.com/ngeo/journal/v9/n9/full/ngeo2778.html | 687-690 | Vol: 9 Issue: 9 | 1752-0894 | Thomson Reuters ISI (SCIE) | English | The age of organic material discharged by rivers provides information about its sources and carbon cycling processes within watersheds. Although elevated ages in fluvially transported organic matter are usually explained by erosion of soils and sedimentary deposits, it is commonly assumed that mainly young organic material is discharged from flat tropical watersheds due to their extensive plant cover and rapid carbon turnover. Here we present compound-specific radiocarbon data of terrigenous organic fractions from a sedimentary archive offshore the Congo River, in conjunction with molecular markers for methane-producing land cover reflecting wetland extent. We find that the Congo River has been discharging aged organic matter for several thousand years, with apparently increasing ages from the mid- to the Late Holocene. This suggests that aged organic matter in modern samples is concealed by radiocarbon from atmospheric nuclear weapons testing. By comparison to indicators for past rainfall changes we detect a systematic control of organic matter sequestration and release by continental hydrology, mediating temporary carbon storage in wetlands. As aridification also leads to exposure and rapid remineralization of large amounts of previously stored labile organic matter, we infer that this process may cause a profound direct climate feedback that is at present underestimated in carbon cycle assessments. | |
| Deep time evidence for climate sensitivity increase with warming | Geophysical Research Letters | Shaffer, G.; Huber, M.; Rondanelli, R.; Pepke Pedersen, J. | 2016 | Biogeoquímica | 10.1002/2016GL069243 | http://onlinelibrary.wiley.com/doi/10.1002/2016GL069243/abstract | 6538-6545 | Vol: 43 Issue: 12 | 0094-8276 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Future global warming from anthropogenic greenhouse gas emissions will depend on climate feedbacks, the effect of which is expressed by climate sensitivity, the warming for a doubling of atmospheric CO2 content. It is not clear how feedbacks, sensitivity, and temperature will evolve in our warming world, but past warming events may provide insight. Here we employ paleoreconstructions and new climate-carbon model simulations in a novel framework to explore a wide scenario range for the Paleocene-Eocene Thermal Maximum (PETM) carbon release and global warming event 55.8 Ma ago, a possible future warming analogue. We obtain constrained estimates of CO2 and climate sensitivity before and during the PETM and of the PETM carbon input amount and nature. Sensitivity increased from 3.3–5.6 to 3.7–6.5 K (Kelvin) into the PETM. When taken together with Last Glacial Maximum and modern estimates, this result indicates climate sensitivity increase with global warming. |
| Holocene tephrochronology around Cochrane (∼ 47 S), southern Chile | Andean Geology | Stern, C.; Moreno, P.; Henríquez, W.; Villa-Martínez, R.; Sagredo, E.; Aravena, J.; De Pol-Holz, R. | 2016 | Biogeoquímica; Dinámica del Clima | 10.5027/andgeoV43n1-a01 | http://www.andeangeology.cl/index.php/revista1/article/view/V43n1-a01 | 1-19 | Vol: 43 Issue: 1 | 0718-7106 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Two Holocene tephras encountered in outcrops, cores and trenches in bogs, and lake cores in the area around Cochrane, southern Chile, are identified (based on their age, tephra glass color and morphology, mineralogy, and both bulk and glass chemistry) as H1 derived from Hudson volcano, and MEN1 derived from Mentolat volcano. New AMS radiocarbon ages indicate systematic differences between those determined in lake cores (MEN1=7,689 and H1=8,440 cal yrs BP) and surface deposits (MEN1=7,471 and H1=7,891 cal yrs BP), with the lake cores being somewhat older. H1 tephra layers range from 8 to 18 cm thick, suggesting that both the area of the 10 cm isopach and the volume of this eruption were larger than previously suggested, but not greatly, and that the direction of maximum dispersion was more to the south. MEN1 tephra layers range from 1-4 cm in thickness, indicating that this was probably a reasonably large (>5 km 3 ) eruption. Some of the lake cores also contain thin layers (<2 cm) of late Holocene H2 tephra and the recent H3 (1991 AD) tephra, both derived from the Hudson volcano. No tephra evidence has been observed for any late Pleistocene tephra, nor for the existence of the supposed Arenales volcano, proposed to be located west of Cochrane. |
| Puyehue-Cordón Caulle eruption of 2011: tephra fall and initial forest responses in the Chilean Andes | Bosque | Swanson, F.; Jones, J.; Crisafulli, C.; González, M.; Lara, A. | 2016 | Servicios Ecosistémicos | 10.4067/S0717-92002016000100009 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-92002016000100009&lng=en&nrm=iso&tlng=en | 85-96 | Vol: 37 Issue: 1 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The 2011 eruption in the Puyehue-Cordón Caulle volcanic complex deposited up to 50 cm of tephra in a plume that intersected the crest of the Andes along Route 215, offering an excellent opportunity to study disturbance effects on native forests along a gradient of tephra depth. Our observations focused on short-term, species-level, tree mortality and sprouting and tephra fall effects on foliage and limb fall. More than 80 % of the thickest deposits were composed of a basal, pumice, gravel layer containing individual clasts up to 6 cm in length overlain by finer gravel and capped by several cm of sandy tephra. In a sample of four plots with tephra thickness ranging from 10 to 50 cm, we observed a wide range of tree mortality: about 8 % of stems living at the time of the eruption were killed by 10 cm of tephra fall and 54 % were killed by 50 cm. However, properties of the affected forest, such as species composition, foliage sprouting and retention (deciduous versus evergreen) characteristics, and tree size/age, strongly influenced survival. The sites with 35 and 50 cm thick deposits were dominated by the deciduous tree Nothofagus pumilio, which was leafless in the austral winter, season of the initial phase of the eruption. The evergreen tree N. dombeyi experienced much higher mortality. The low density of the falling pumice particles appeared to cause minimal abrasion of the canopy. |
| Mitigation of Drought Negative Effect on Ecosystem Productivity by Vegetation Mixing | Journal of Geophysical Research: Biogeosciences | Van den Hoof, C.; Lambert, F. | 2016 | Modelación y Sistemas de Observación | 10.1002/2016JG003625 | http://onlinelibrary.wiley.com/doi/10.1002/2016JG003625/abstract | 2667-2683 | Vol: 121 Issue: 10 | 0148-0227 | Thomson Reuters ISI (SCIE) | English | Vegetation diversity and interaction is thought to have a beneficial effect on ecosystem functioning, particularly improving ecosystem resistance to drought. This is of significant importance in the context of a warmer world, as extreme events such as droughts become more likely. Most of the studies performed so far on vegetation interaction are based on observations. Here we use the land surface model JULES to study the potential of vegetation mixing to mitigate the negative effect of drought events on the land surface through interaction, a mechanism which is difficult to study in situ at large scales. Using a set of simulations with mixed and unmixed vegetation, we show that the carbon, water, and energy fluxes are significantly affected by vegetation competition for water resources. The interaction is in general beneficial for the ecosystem carbon assimilation due to a better use of water resources. This benefit is highest when traits between vegetation types concerning resource competition overlap least. For a tree-grass combination, mixing improves carbon assimilation by 5% to 8% during summer. The NPP benefit of mixing increases further under progressively more resource-limited conditions up to an inflection point with a benefit of 14%, after which it falls back to zero under extremely dry conditions. Mixing also tends to reduce the inter-annual variability of the ecosystem carbon sink and therefore improves the resistance of the ecosystem. Our results highlight the importance of vegetation interaction in climate simulations and impact studies, and the potential of vegetation mixing as a mitigation tool. | |
| Tectonic ecology of the temperate forests of South America and New Zealand | New Zealand Journal of Botany | Veblen, T.; González, M.; Stewart, G.; Kitzberger, T.; Brunet, J. | 2016 | Servicios Ecosistémicos | 10.1080/0028825X.2015.1130726 | http://www.tandfonline.com/doi/full/10.1080/0028825X.2015.1130726 | 223-246 | Vol: 54 Issue: 2 | 0028-825X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Ecological disturbances triggered by earthquakes and volcanic eruptions are of fundamental importance in structuring the temperate forests of southwestern South America and New Zealand. We review studies of the ecological effects of these tectonic phenomena and how they have been central to progress in the modern development of forest ecology in both regions. Studies of tectonic influences on the dynamics of southern temperate rainforests of Chile and New Zealand published in the 1970s and early 1980s contributed prominently to the shift away from the equilibrium paradigms dominant globally in the 1960s and towards modern non- equilibrium frameworks of forest dynamics. Empirical studies of tectonic ecology in these temperate forests in combination with critical evaluations of earlier successional theory have significantly advanced understanding of the roles of coarse scale disturbance in the dynamics of forests in southwestern South America and New Zealand. Recognition that cohort forest For Peer Review Only structures triggered by exogenous disturbances such as wind storms and tectonic events are the norm rather than all-aged structures has been of fundamental importance to understanding the dynamics of these forests. The non-equilibrium patch dynamics framework for interpreting forest structure and dynamics bolstered by tectonic ecology studies in southern South America and New Zealand was of key importance in refining older views of these forests as being out of equilibrium with contemporary climate, revising understanding of the effects of introduced browsing animals on forest structure, and guiding the development of appropriate forest management practices. |
| Climate relevant trace gases (N2O and CH4) in the Eurasian Basin (Arctic Ocean) | Deep Sea Research Part I: Oceanographic Research Papers | Verdugo, J.; Damm, E.; Snoeijs, P.; Díez, B.; Farías, L. | 2016 | Biogeoquímica | 10.1016/j.dsr.2016.08.016 | http://www.sciencedirect.com/science/article/pii/S0967063715301345 | 84-94 | Vol: 117 | 0967-0637 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The concentration of greenhouse gases, including nitrous oxide (N2O), methane (CH4), and compounds such as total dimethylsulfoniopropionate (DMSPt), along with other oceanographic variables were measured in the ice-covered Arctic Ocean within the Eurasian Basin (EAB). The EAB is affected by the perennial ice-pack and has seasonal microalgal blooms, which in turn may stimulate microbes involved in trace gas cycling. Data collection was carried out on board the LOMROG III cruise during the boreal summer of 2012. Water samples were collected from the surface to the bottom layer (reaching 4300 m depth) along a South-North transect (SNT), from 82.19°N, 8.75°E to 89.26°N, 58.84°W, crossing the EAB through the Nansen and Amundsen Basins. The Polar Mixed Layer and halocline waters along the SNT showed a heterogeneous distribution of N2O, CH4 and DMSPt, fluctuating between 42-111 and 27–649% saturation for N2O and CH4, respectively; and from 3.5 to 58.9 nmol L−1 for DMSPt. Spatial patterns revealed that while CH4 and DMSPt peaked in the Nansen Basin, N2O was higher in the Amundsen Basin. In the Atlantic Intermediate Water and Arctic Deep Water N2O and CH4 distributions were also heterogeneous with saturations between 52% and 106% and 28% and 340%, respectively. Remarkably, the Amundsen Basin contained less CH4 than the Nansen Basin and while both basins were mostly under-saturated in N2O. We propose that part of the CH4 and N2O may be microbiologically consumed via methanotrophy, denitrification, or even diazotrophy, as intermediate and deep waters move throughout EAB associated with the overturning water mass circulation. This study contributes to baseline information on gas distribution in a region that is increasingly subject to rapid environmental changes, and that has an important role on global ocean circulation and climate regulation. |
| Unravel biophysical factors on river water quality response in Chilean Central-Southern watersheds | Environmental Monitoring and Assessment | Yevenes, M.; Arumí, J.; Farías, L. | 2016 | Biogeoquímica | 10.1007/s10661-016-5235-1 | http://link.springer.com/10.1007/s10661-016-5235-1 | 264-281 | Vol: 188 Issue: 5 | 0167-6369 | Thomson Reuters ISI (SCIE) | English | Identifying the key anthropogenic (land uses) and natural (topography and climate) biophysical drivers affecting river water quality is essential for efficient management of water resources. We tested the hypothesis that water quality can be predicted by different biophysical factors. Multivariate statistics based on a geographical information system (GIS) were used to explore the influence of factors (i.e., precipitation, topography, and land uses) on water quality (i.e., nitrate (NO 3 − ), phosphate (PO 4 3 − ), silicate (Si(OH)4), dissolved oxygen (DO), suspended solids (TSS), biological oxygen demand (DO), temperature (T), conductivity (EC), and pH) for two consecutive years in the Itata and Biobío river watersheds, Central Chile (36° 00′ and 38° 30′). The results showed that (NO 3 − ), (PO 4 3 − ), Si(OH)4, TSS, EC, and DO were higher during rainy season (austral fall, winter, and spring), whereas BOD and temperature were higher during dry season. The spatial variation of these parameters in both watersheds was related to land use, topography (e.g., soil moisture, soil hydrological group, and erodability), and precipitation. Soil hydrological group and soil moisture were the strongest explanatory predictors for PO 4 3 − , Si(OH)4 and EC in the river, followed by land use such as agriculture for NO 3 − and DO and silviculture for TSS and Si(OH)4. High-resolution water leaching and runoff maps allowed us to identify agriculture areas with major probability of water leaching and higher probability of runoff in silviculture areas. Moreover, redundancy analysis (RDA) revealed that land uses (agriculture and silviculture) explained in 60 % the river water quality variation. Our finding highlights the vulnerability of Chilean river waters to different biophysical drivers, rather than climate conditions alone, which is amplified by human-induced degradation. | |
| Tracing Nitrate-Nitrogen Sources and Modifications in a Stream Impacted by Various Land Uses, South Portugal | Water | Yevenes, M.; Soetaert, K.; Mannaerts, C. | 2016 | Biogeoquímica | 10.3390/w8090385 | http://www.mdpi.com/2073-4441/8/9/385 | art385 | Vol: 8 Issue: 9 | 2073-4441 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The identification of nitrate-nitrogen (NO3–N) origin is important in the control of surface and ground water quality. These are the main sources of available drinking water. Stable isotopes (15N and 18O) for NO3–N and along with a 1-D reactive transport model were used to study the origin and processes that lead to nitrogen transformation and loss in a major stream that flows into a reservoir within an intensively cultivated catchment area (352 km2) in Alentejo-Portugal. Seasonal water samples (October–November 2008, March 2009 and September 2009) of stream surface water, wells and sediment pore water were collected. The results showed consistently increasing isotope values and decreasing NO3–N concentrations downstream. During winter (wet period, November 2008 and March 2009) slightly higher NO3–N concentrations were found in comparison to early fall (dry period: October 2008) and summer (dry period: September 2009). Isotopic composition of 15N and 18O values in surface water samples from the stream and wells indicated that the dominant NO3–N sources were derived mainly from the soil and fertilizers. There was also significant nitrification in surface water at the head of the stream. Sediment pore waters showed high NO3–N values near the sediment-water interface (reaching 25 mg·N·L−1) and NO3–N concentrations sharply decreasing with sediment depth, suggesting significant NO3–N consumption. Denitrification was also detected using the 15N signature in upstream waters, but not downstream where very low NO3–N levels were measured. In the stream, the calculated isotopic enrichment factor for NO3–N was −2.9‰ for 15N and −1.78 for 18O, this indicates that denitrification accounts for 7.8% to 48% of nitrate removal. |
| Detailed dynamic land cover mapping of Chile: Accuracy improvement by integrating multi-temporal data | Remote Sensing of Environment | Zhao, Y.; Feng, D.; Yu, L.; Wang, X.; Chen, Y.; Bai, Y.; Hernández, H.; Galleguillos, M.; Estades, C.; Biging, G.; Radke, J.; Gong, P. | 2016 | Servicios Ecosistémicos | 10.1016/j.rse.2016.05.016 | http://www.sciencedirect.com/science/article/pii/S0034425716302188 | 170-185 | Vol: 183 | 0034-4257 | Thomson Reuters ISI (SCIE) | English | Stretching over 4300 km north to south, Chile is a special country with complicated landscapes and rich biodiversity. Accurate and timely updated land cover map of Chile in detailed classification categories is highly demanded for many applications. A conclusive land cover map integrated from multi-seasonal mapping results and a seasonal dynamic map series were produced using Landsat 8 imagery mainly acquired in 2013 and 2014, supplemented by MODIS Enhanced Vegetation Index data, high resolution imagery on Google Earth, and Shuttle Radar Topography Mission DEM data. The overall accuracy is 80% for the integrated map at level 1 and 73% for level 2 based on independent validation data. Accuracies for seasonal map series were also assessed, which is around 70% for each season, greatly improved by integrated use of seasonal information. The importance of growing season imagery was proved in our analysis. The analysis of the spatial variation of accuracies among various ecoregions indicates that the accuracy for land cover mapping decreases gradually from central Chile to both north and south. More mapping efforts for those ecoregions are needed. In addition, the training dataset includes sample points spatially distributed in the whole country, temporally distributed throughout the year, and categorically encompassing all land cover types. This training dataset constitutes a universal sample set allowing us to map land cover from any Landsat 8 image acquired in Chile without additional ad hoc training sample collection. | |
| Informe a la Nación: La megasequía 2010-2015: Una lección para el futuro | 2015 | Biogeoquímica; Dimensión Humana; Dinámica del Clima; Modelación y Sistemas de Observación; Servicios Ecosistémicos | https://www.cr2.cl/informe-a-la-nacion-la-megasequia-2010-2015-una-leccion-para-el-futuro/ | cr2.cl | |||||||||
| The cyanobacterium Mastigocladus fulfills the nitrogen demand of a terrestrial hot spring microbial mat | The ISME Journal | Alcamán, M.; Fernandez, C.; Delgado-Huertas, A.; Bergman, B.; Díez, B. | 2015 | Biogeoquímica | 10.1038/ismej.2015.63 | http://www.nature.com/ismej/journal/v9/n10/full/ismej201563a.html | 2290–2303 | Vol: 9 Issue: 10 | 1751-7362 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Cyanobacteria from Subsection V (Stigonematales) are important components of microbial mats in non-acidic terrestrial hot springs. Despite their diazotrophic nature (N2 fixers), their impact on the nitrogen cycle in such extreme ecosystems remains unknown. Here, we surveyed the identity and activity of diazotrophic cyanobacteria in the neutral hot spring of Porcelana (Northern Patagonia, Chile) during 2009 and 2011-2013. We used 16S rRNA and the nifH gene to analyze the distribution and diversity of diazotrophic cyanobacteria. Our results demonstrate the dominance of the heterocystous genus Mastigocladus (Stigonematales) along the entire temperature gradient of the hot spring (69-38 °C). In situ nitrogenase activity (acetylene reduction), nitrogen fixation rates (cellular uptake of (15)N2) and nifH transcription levels in the microbial mats showed that nitrogen fixation and nifH mRNA expression were light-dependent. Nitrogen fixation activities were detected at temperatures ranging from 58 °C to 46 °C, with maximum daily rates of 600 nmol C2H4 cm(-2) per day and 94.1 nmol N cm(-2) per day. These activity patterns strongly suggest a heterocystous cyanobacterial origin and reveal a correlation between nitrogenase activity and nifH gene expression during diurnal cycles in thermal microbial mats. N and C fixation in the mats contributed ∼3 g N m(-2) per year and 27 g C m(-2) per year, suggesting that these vital demands are fully met by the diazotrophic and photoautotrophic capacities of the cyanobacteria in the Porcelana hot spring. |
| Resilience for disaster risk management in a changing climate: Practitioners’ frames and practices | Global Environmental Change | Aldunce, P.; Beilin, R.; Howden, M.; Handmer, J. | 2015 | Dimensión Humana | 10.1016/j.gloenvcha.2014.10.010 | http://www.sciencedirect.com/science/article/pii/S0959378014001770 | 1–11 | Vol: 30 | 0959-3780 | Thomson Reuters ISI (SCIE; SSCI) | English | There is a growing use of resilience ideas within the disaster risk management literature and policy domain. However, few empirical studies have focused on how resilience ideas are conceptualized by practitioners, as they implement them in practice. Using Hajer's 'social-interactive discourse theory' this research contributes to the understanding of how practitioners frame, construct and make sense of resilience ideas in the context of changes in institutional arrangements for disaster risk management that explicitly include the resilience approach and climate change considerations. The case study involved the roll out of the Natural Disaster Resilience Program in Queensland, Australia, and the study involved three sites in Queensland. The methods used were observation of different activities and the physical sites, revision of documents related to the Natural Disaster Resilience Program and in-depth semi-structured interviews with key informants, all practitioners who had direct interaction with the program. The research findings show that practitioners construct the meaning of disaster resilience differently, and these are embedded in diverse storylines. Within these storylines, practitioners gave different interpretations and emphasis to the seven discourse categories that characterized their resilience discourse. Self-reliance emerged as one of the paramount discourse categories but we argue that caution needs to be used when promoting values of self-reliance. If the policy impetus is a focus on learning, research findings indicate it is also pertinent to move from experiential learning toward social learning. The results presented in this study provide helpful insights to inform policy design and implementation of resilience ideas in disaster risk management and climate change, and to inform theory. | |
| Identificación de actores relacionados a la sequía en Chile | Aldunce, P.; Borquez, R.; Indvik, K.; Lillo, G. | 2015 | Dimensión Humana | https://www.cr2.cl/identificacion-de-actores-relacionados-a-la-sequia-en-chile/ | 47 | ||||||||
| A correlated shortening of the North and South American monsoon seasons in the past few decades | Climate Dynamics | Arias, P.; Fu, R.; Vera, C.; Rojas, M. | 2015 | Modelación y Sistemas de Observación | 10.1007/s00382-015-2533-1 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84947491620&partnerID=tZOtx3y1 http://link.springer.com/article/10.1007%2Fs00382-015-2533-1 | 3183–3203 | Vol: 45 Issue: 11-12 | 0930-7575 | Thomson Reuters ISI (SCIE) | English | Our observational analysis shows that the wet seasons of the American monsoon systems have shortened since 1978 due to correlated earlier retreats of the North American monsoon (NAM) and late onsets of the southern Amazon wet season, an important part of the South American monsoon (SAM). These changes are related to the combination of the global sea surface temperature (SST) warming mode, the El Niño-Southern Oscillation (ENSO), the Atlantic Multidecadal Oscillation (AMO), the westward shift of the North Atlantic subtropical high (NASH), and the enhancement of Pacific South American and Pacific North American wave train patterns, which induces variations of the regional circulation at interannual and decadal scales. The joint contributions from these forcing factors are associated with a stronger and more equatorward regional Hadley cell, which enhances convergence towards the equator, strengthening and possibly delaying the retreat of the tropical part of the NAM. This in turn accelerates the demise of the northern NAM and delays the reversal of the cross-equatorial flow over South America, reducing moisture transport to the SAM and delaying its onset. In addition, the thermodynamic response to warming appears to cause local drier land conditions over both regions, reinforcing the observed changes in these monsoons. Although previous studies have identified the isolated influence of the regional Hadley cell, ENSO, AMO, global SST warming, and NASH on the NAM, the correlated changes between NAM and SAM through variations of the cross-equatorial flow had not been established before. | |
| Projected strengthening of Amazonian dry season by constrained climate model simulations | Nature Climate Change | Boisier, J.; Ciais, P.; Ducharne, A.; Guimberteau, M. | 2015 | Dinámica del Clima | 10.1038/nclimate2658 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84932110744&partnerID=tZOtx3y1 | 656–660 | Vol: 5 Issue: 7 | 1758-678X | Thomson Reuters ISI (SCIE; SSCI) | English | The vulnerability of Amazonian rainforest, and the ecological services it provides, depends on an adequate supply of dry-season water, either as precipitation or stored soil moisture. How the rain-bearing South American monsoon will evolve across the twenty-first century is thus a question of major interest. Extensive savanization, with its loss of forest carbon stock and uptake capacity, is an extreme although very uncertain scenario. We show that the contrasting rainfall projections simulated for Amazonia by 36 global climate models (GCMs) can be reproduced with empirical precipitation models, calibrated with historical GCM data as functions of the large-scale circulation. A set of these simple models was therefore calibrated with observations and used to constrain the GCM simulations. In agreement with the current hydrologic trends, the resulting projection towards the end of the twenty-first century is for a strengthening of the monsoon seasonal cycle, and a dry-season lengthening in southern Amazonia. With this approach, the increase in the area subjected to lengthy - savannah-prone - dry seasons is substantially larger than the GCM-simulated one. Our results confirm the dominant picture shown by the state-of-the-art GCMs, but suggest that the â € model democracy'view of these impacts can be significantly underestimated. | |
| Projected river discharge in the Euphrates–Tigris Basin from a hydrological discharge model forced with RCM and GCM outputs | Climate Research | Bozkurt, D.; Sen, O.; Hagemann, S. | 2015 | Modelación y Sistemas de Observación | 10.3354/cr01268 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84920986276&partnerID=tZOtx3y1 | 131–147 | Vol: 62 Issue: 2 | 0936-577X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | The hydrological discharge (HD) model of Max Planck Institute for Meteorology is forced by a variety of climate model datasets to investigate the future of discharge in the Euphrates-Tigris Basin. The data include daily time series of surface runoff and sub-surface runoff outputs of 2 global climate models (GCMs) (the SRES A1B scenario simulation of ECHAM5/MPIOM and the RCP 4.5 scenario simulation of MPI-ESM-LR) and the dynamically downscaled outputs of ECHAM5/MPIOM and NCAR-CCSM3 scenario (SRES A1FI, A2 and B1) simulations. The suite of simulations enables a comprehensive analysis of the projected river discharge, and allows a comparison between CMIP5 simulations of MPI-ESM-LR and CMIP3 results from its predecessor ECHAM5/MPIOM on a basin scale. We demonstrate that HD simulations forced with relatively low-resolution GCM outputs are not good at reproducing the seasonal cycle of discharge, which is typically characterized by less flow in the peak season and an earlier peak in annual discharge. Simulations forced with the MPI-ESM-LR yield more robust information on the annual cycle and timing of the annual peak discharge than ECHAM5-forced simulations. In contrast to GCM-forced simulations, high-resolution RCM-forced simulations reproduce the annual cycle of discharge reasonably well; however, overestimation of discharge during the cold season and bias in the timing of springtime snowmelt peaks persist in the RCM-forced simulations. Different RCM-forced scenario simulations indicate substantial decreases in mean annual discharge for the Euphrates and Tigris Rivers by the end of the century, ranging from 19-58%. Significant temporal shifts to earlier days (3-5 wk by the end of the 21st century) in the center time of the discharges are also projected for these rivers. As the basin is considered water-stressed and the region is strongly influenced by water-scarcity events, these unfavorable changes may potentially increase water disputes among the basin countries. |
| Modelled glacier equilibrium line altitudes during the mid-Holocene in the southern mid-latitudes | Climate of the Past | Bravo, C.; Rojas, M.; Anderson, B.; Mackintosh, A.; Sagredo, E.; Moreno, P. | 2015 | Dinámica del Clima; Modelación y Sistemas de Observación | 10.5194/cp-11-1575-2015 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84948461078&partnerID=tZOtx3y1 | 1575–1586 | Vol: 11 Issue: 11 | 1814-9324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Glacier behaviour during the mid-Holocene (MH, 6000 years BP) in the Southern Hemisphere provides observational data to constrain our understanding of the origin and propagation of palaeoclimate signals. In this study we examine the climatic forcing of glacier response in the MH by evaluating modelled glacier equilibrium line altitudes (ELAs) and climatic conditions during the MH compared with pre-industrial time (PI, year 1750). We focus on the middle latitudes of the Southern Hemisphere, specifically Patagonia and the South Island of New Zealand. Climate conditions for the MH were obtained from PMIP2 model simulations, which in turn were used to force a simple glacier mass balance model to simulate changes in ELA. In Patagonia, the models simulate colder conditions during the MH in austral summer (-0.2 °C), autumn (-0.5 °C), and winter (-0.4), and warmer temperatures (0.2 °C) during spring. In the Southern Alps the models show colder MH conditions in autumn (-0.7 °C) and winter (-0.4 °C), warmer conditions in spring (0.3 °C), and no significant change in summer temperature. Precipitation does not show significant changes but exhibits a seasonal shift, with less precipitation from April to September and more precipitation from October to April during the MH in both regions. The mass balance model simulates a climatic ELA that is 15-33 m lower during the MH compared with PI conditions. We suggest that the main causes of this difference are driven mainly by colder temperatures associated with the MH simulation. Differences in temperature have a dual effect on glacier mass balance: (i) less energy is available for ablation during summer and early autumn and (ii) lower temperatures cause more precipitation to fall as snow rather than rain in late autumn and winter, resulting in more accumulation and higher surface albedo. For these reasons, we postulate that the modelled ELA changes, although small, may help to explain larger glacier extents observed by 6000 years BP in South America and New Zealand. |
| Evaluation of impacts of management in an anthropogenic peatland using field and remote sensing data | Ecosphere | Cabezas, J.; Galleguillos, M.; Valdés, A.; Fuentes, J.; Pérez, C.; Perez-Quezada, J. | 2015 | Servicios Ecosistémicos | 10.1890/ES15-00232.1 | http://doi.wiley.com/10.1890/ES15-00232.1 | art282 | Vol: 6 Issue: 12 | 2150-8925 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Peatlands are a type of wetland characterized by the accumulation of organic matter, called peat, and are important carbon reservoirs. In areas with poor drainage, human-induced forest fires and logging can produce flooded conditions and organic matter accumulation, which generates an ecosystem called anthropogenic peatland. Productive management activities such as Sphagnum moss harvesting and livestock grazing take place there. Our hypothesis was that productive management has a strong impact on the aboveground C reservoir and increases the presence of exotic species. We established 44 sampling points in a 16-ha anthropogenic peatland on Chiloé Island, Chile, comparing productive and conservation types of managements. Carbon stocks, vegetation structure and composition variables were quantified. These variables were used to classify the ecosystem into microsites to analyze the different locations in the peatland. In addition, predictive models of aboveground carbon were created using Landsat 8 OLI and Pleiades images. The results revealed a carbon stock of 11.99 ± 0.77 kg C m−2, which is smaller than in natural peatlands, and showed a wide variability of conditions within the peatland itself. This variability, mainly expressed in aboveground carbon, produces microsites dominated by either shrubs, species of the genus Juncus or grasses. Productive management reduced accumulated carbon in the aboveground stock and in the woody debris. However, the strongest impact was found on the vegetation variables, with a decrease in total cover, cover of shrubs and herbaceous plants, and in vegetation height. There was also an increase in the richness and presence of exotic species. The spatial prediction of aboveground carbon yielded significant results using only spectral indices, showing also that the impact of productive management is not homogenous, being less intense in waterlogged areas. This study is the first to quantify carbon reservoirs in this type of ecosystem and to propose variables that can be used as indicators of the impact of human activities. |
| The influence of anoxia and substrate availability on N2O cycling by denitrification in the upper boundary of the oxygen minimum zone off northern Chile | Journal of Marine Research | Castro-González, M.; Farías, L. | 2015 | Biogeoquímica | 10.1357/002224015817391285 | http://www.ingentaconnect.com/content/jmr/jmr/2015/00000073/00000006/art00002?crawler=true | 185–205 | Vol: 73 Issue: 6 | 0022-2402 | Thomson Reuters ISI (ESCI) | English | Strong accumulations of N2O at oxyclines are some of the most conspicuous features of the world’s oceans. However, the origin of these maxima, and the relative contribution of nitrification and denitrification in N2O cycling, remains unclear. In order to gain insight into the importance of denitrification and factors regulating N2O cycling at upper oxyclines in the eastern South Pacific, the production and consumption of N2O by denitrification were measured using a classical acetylene method under induced anoxia with the addition of an electron acceptor (nitrite) and donors (sodium acetate and glucose). The results indicated that decreased O2 clearly affected the ratio in which N2O is reduced to N2 at the midoxycline (∼40 m depth) and at the oxycline’s base (∼80 m depth). Under induced anoxia, higherN2Oproduction (fromNO− 2 toN2Oof 67.2 nM d−1) occurred at 40mdepth, with half of the total quantity being consumed by denitrification (from N2OtoN2 of 32 nM d−1); conversely,100%of theN2Owas reduced toN2 at 80mdepth. In comparison with previously reported results at the base of the oxycline at an offshore station, the addition ofNO− 2 (as sodium nitrite) along with dissolved organic carbon (as sodium acetate and glucose) doubled the net N2O production by denitrification (∼20 nM d−1). Our results suggest that decreasing O2 levels along with an increased availability of NO− 2 and organic compounds in the upper oxycline may impact the N2O/N2 ratio and, therefore, the N2O efflux to the atmosphere | |
| Structure of denitrifying communities reducing N2O at suboxic waters off northern Chile and Perú | Revista de Biologia Marina y Oceanografia | Castro-González, M.; Ulloa, O.; Farías, L. | 2015 | Biogeoquímica | 10.4067/S0718-19572015000100008 | http://scielo-test.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-19572015000100008&lng=en&nrm=iso&tlng=en | 95–110 | Vol: 50 Issue: 1 | 0717-3326 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The nosZ gene, which encodes for N2 O reduction to N2 , was used to study the structure of denitrifying communities in the oxygen minimum zone off Chilean and Peruvian coast throughout terminal restriction fragment length polymorphism (TRFLP) and cloning of nosZ genes. TRFLP analysis showed little diversity of nosZ genes at suboxic depths (Oxygen Minimum Zone´s core) compared with depths where O2 largely varied (upper limit of OMZ or ULOMZ). The nosZ-denitrifying communities showed differences in its structure between geographical locations and time sampling suggesting an association with the shift in the environmental conditions. The canonical correspondence analysis showed that the environmental parameters selected as predictor variables (N2 O, O2 , NH4 + and NO2 -) explained well the differences in nosZ-denitrifying community composition among sampling sites. The phylogenetic analysis showed little nosZ sequence diversity and grouped 81% of nosZ-clones near the cluster of sediments sequences from Pacific. Our sequences did not branch with any known denitrifying bacteria or seawater nosZ-sequences available, demonstrating the novelty of phylotypes founded in this area. |
| An unaccounted for N2O sink in the surface water of the eastern subtropical South Pacific: Physical versus biological mechanisms | Progress in Oceanography | Cornejo, M.; Murillo, A.; Farías, L. | 2015 | Biogeoquímica | 10.1016/j.pocean.2014.12.016 | http://www.sciencedirect.com/science/article/pii/S0079661114002262 | 12–23 | Vol: 137 | 0079-6611 | Thomson Reuters ISI (SCIE) | English | Nitrous oxide (N2O) is a trace gas affecting atmospheric radiative forcing through its greenhouse effect in the troposphere and destroying the ozone in the stratosphere. The oceans account for one-third of the global atmospheric N2O emissions, in which they are primarily cycled by nitrification and denitrification, with high N2O production in the subsurface waters. The surface waters are generally reported to be in equilibrium or slightly supersaturated with respect to the atmosphere. However, surface N2O sub-saturations have been observed in several regions of the world's oceans, such as off south-central Chile, which is bathed by the Sub-Antarctic Water Mass (SAAW), where N2O subsaturations as low as 35% have been registered during the austral spring and summer. An analysis of the mechanisms driving such surface N2O subsaturations (physical or biological) showed that physical mechanisms were not responsible for the high surface N2O deficit. In contrast, in situ potential experiments in surface waters with 15N2O addition showed an active biological N2O fixation (between 0.43 and 87.34nmol/L/d), with the highest N2O fixation rates associated with the SAAW (25.25-25.75kg/m3).Additionally, incubation experiments with 15N2O in surface water samples from one oceanic station showed high 15N-POM enrichment (0.44‰) and an inhibition of 15N-POM enrichment when an additional nitrogen source was added (NO2 - and NH4 +). These results suggest the existence of a mechanism able to use several nitrogen sources, including N2O. Molecular analyses (16S rRNA gene) from these experiments showed the presence of three major groups of bacteria: Gammaproteobacteria, Flavobacteria and Cyanobacteria, with Synechococcus sp. being the dominant group in the culture. However, the analysis of the nifH gene showed a taxonomic affiliation to the order Stigonematales associated with Mastigocladus sp. and Fischerella sp. and the order Oscillatoriales associated with Trichodesmium sp.Finally, the oceanic region exhibiting surface N2O subsaturations acts as a sink for atmospheric N2O, consuming ∼11.4 Gg of N2O in a six-month period. The N2O levels in the sink are 75% higher than those of the reported N2O source from the coastal band. The balance between the oceanic region and the coastal band results in a sink region of 4.94 Gg of N2O during this period. | |
| Presence of nitrous oxide hotspots in the coastal upwelling area off central Chile: an analysis of temporal variability based on ten years of a biogeochemical time series | Environmental Research Letters | Farías, L.; Besoain, V.; García-Loyola, S. | 2015 | Biogeoquímica | 10.1088/1748-9326/10/4/044017 | http://iopscience.iop.org/1748-9326/10/4/044017/article/ | art044017 | Vol: 10 Issue: 4 | 1748-9326 | Thomson Reuters ISI (SCIE) | English | Seasonal and inter-annual variabilities of biogeochemical variables, including nitrous oxide (N2O), an important climate active gas, were analyzed during monthly observations between 2002 and 2012 at an ocean Time-Series station in the coastal upwelling area off central Chile (36° 30.8′; 73° 15′). Oxygen, N2O, nutrients and chlorophyll-a (Chl-a) showed clear seasonal variability associated with upwelling favorable winds (spring–summer) and also inter-annual variability, which in the case of N2O was clearly observed during the occurrence of N2O hotspots with saturation levels of up to 4849%. These hotspots consistently took place during the upwelling-favorable periods in 2004, 2006, 2008, 2010 and 2011, below the mixed layer (15–50 m depth) in waters with hypoxia and some accumulation. The N2O hotspots displayed excesses of N2O (ΔN2O) three times higher than the average monthly anomalies (2002–2012). Estimated relationships of ΔN2O versus apparent oxygen utilization (AOU), and ΔN2O versus suggest that aerobic ammonium oxidation (AAO) and partial denitrification are the processes responsible for high N2O accumulation in subsurface water. Chl-a levels were reasonably correlated with the presence of the N2O hotspots, suggesting that microbial activities fuelled by high availability of organic matters lead to high N2O production. As a result, this causes a substantial N2O efflux into the atmosphere of up to 260 μmol m−2 d−1. The N2O hotspots are transient events or hot moments, which may occur more frequently than they are observed. If so, this upwelling area is producing and emitting greater than expected amounts of N2O and is therefore an important N2O source that should be considered in the global atmospheric N2O balance. | |
| Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean | Biogeosciences | Farías, L.; Florez-Leiva, L.; Besoain, V.; Sarthou, G.; Fernández, C. | 2015 | Biogeoquímica | 10.5194/bg-12-1925-2015 | http://www.biogeosciences.net/12/1925/2015/ | 1925–1940 | Vol: 12 Issue: 6 | 1726-4170 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The concentrations of greenhouse gases (GHGs), such as nitrous oxide (N |
| Temporal and spatial variability of biological nitrogen fixation off the upwelling system of central Chile (35-38.5°S) | Journal of Geophysical Research: Oceans | Fernandez, C.; González, M.; Muñoz, C.; Molina, V.; Farías, L. | 2015 | Biogeoquímica | 10.1002/2014JC010410 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84934894933&partnerID=tZOtx3y1 | 3330–3349 | Vol: 120 Issue: 5 | 0148-0227 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Although N |
| Spatio-temporal distribution patterns of Mediterranean cold-water corals (Lophelia pertusa and Madrepora oculata) during the past 14,000 years | Deep Sea Research Part I: Oceanographic Research Papers | Fink, H.; Wienberg, C.; De Pol-Holz, R.; Hebbeln, D. | 2015 | Biogeoquímica | 10.1016/j.dsr.2015.05.006 | http://linkinghub.elsevier.com/retrieve/pii/S0967063715001028 http://www.scopus.com/inward/record.url?eid=2-s2.0-84934899742&partnerID=tZOtx3y1 | 37–48 | Vol: 103 | 0967-0637 | Thomson Reuters ISI (SCIE) | English | This study presents newly obtained coral ages of the cold-water corals Lophelia pertusa and Madrepora oculata collected in the Alboran Sea and the Strait of Sicily (Urania Bank). These data were combined with all available Mediterranean Lophelia and Madrepora ages compiled from literature to conduct a basin-wide assessment of the spatial and temporal occurrence of these prominent framework-forming scleractinian species in the Mediterranean realm and to unravel the palaeo-environmental conditions that controlled their proliferation or decline. For the first time special focus was placed on a closer examination of potential differences occurring between the eastern and western Mediterranean sub-basins. Our results clearly demonstrate that cold-water corals occurred sparsely in the entire Mediterranean during the last glacial before becoming abundant during the Bølling-Allerød warm interval, pointing to a basin-wide, almost concurrent onset in (re-)colonisation after ∼13.5. ka. This time coincides with a peak in meltwater discharge originating from the northern Mediterranean borderlands which caused a major reorganisation of the Mediterranean thermohaline circulation. During the Younger Dryas and Holocene, some striking differences in coral proliferation were identified between the sub-basins such as periods of highly prolific coral growth in the eastern Mediterranean Sea during the Younger Dryas and in the western basin during the Early Holocene, whereas a temporary pronounced coral decline during the Younger Dryas was exclusively affecting coral sites in the Alboran Sea. Comparison with environmental and oceanographic data revealed that the proliferation of the Mediterranean corals is linked with enhanced productivity conditions. Moreover, corals thrived in intermediate depths and showed a close relationship with intermediate water mass circulation in the Mediterranean sub-basins. For instance, reduced Levantine Intermediate Water formation hampered coral growth in the eastern Mediterranean Sea during sapropel S1 event as reduced Winter Intermediate Water formation did in the westernmost part of the Mediterranean (Alboran Sea) during the Mid-Holocene. Overall, this study clearly demonstrates the importance to consider region-specific environmental changes as well as species-specific environmental preferences in interpreting coral chronologies. Moreover, it highlights that the occurrence or decline of cold-water corals is not controlled by one key parameter but rather by a complex interplay of various environmental variables. | |
| Photosynthetic responses of trees in high-elevation forests: Comparing evergreen species along an elevation gradient in the Central Andes. | AoB plants | García-Plazaola, J.; Rojas, R.; Christie, D.; Coopman, R. | 2015 | Dinámica del Clima | 10.1093/aobpla/plv058 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84939789142&partnerID=tZOtx3y1 http://aobpla.oxfordjournals.org/content/7/plv058.abstract?ct | plv058 | Vol: 7 | 2041-2851 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Plant growth at extremely high elevations is constrained by high daily thermal amplitude, strong solar radiation, and water scarcity. These conditions are particularly harsh in the tropics, where the highest elevation treelines occur. In this environment the maintenance of a positive carbon balance involves protecting the photosynthetic apparatus and taking advantage of any climatically favorable periods. To characterize photoprotective mechanisms at such high elevations, and particularly to address the question of whether these mechanisms are the same as those previously described in woody plants along extratropical treelines, we have studied photosynthetic responses in Polylepis tarapacana in the central Andes (18 °S) along an elevational gradient from 4,300 to 4,900 m. For comparative purposes this gradient has been complemented with a lower elevation site (3,700 m) where another Polylepis species (P. rugulosa) occurs. During the daily cycle, two periods of photosynthetic activity were observed: one during the morning when, despite low temperatures, assimilation was high; and the second starting at noon when the stomata closed because of a rise in the vapor pressure deficit and thermal dissipation is prevalent over photosynthesis. From dawn to noon there was a decrease in the content of antenna pigments (chlorophyll b and neoxanthin), together with an increase in the content of xanthophyll cycle carotenoids. These results could be caused by a reduction in the antenna size along with an increase in photo-protection. Additionally, photo-protection was enhanced by a partial overnight retention of de-epoxised xanthophylls. The unique combination of all of these mechanisms made possible the efficient use of the favorable conditions during the morning while still providing enough protection for the rest of the day. This strategy differs completely from that of extratropical mountain trees, which uncouple light-harvesting and energy-use during long periods of unfavorable, winter conditions. |
| Timing of occupation and regional settlement patterns revealed by time-series analyses of an archaeological radiocarbon database for the South-Central Andes (16°–25°S) | Quaternary International | Gayo, E.; Latorre, C.; Santoro, C. | 2015 | Biogeoquímica | 10.1016/j.quaint.2014.09.076 | http://www.sciencedirect.com/science/article/pii/S1040618214007496 | 4–14 | Vol: 356 | 1040-6182 | Thomson Reuters ISI (SCIE) | English | Developing spatially resolved high-resolution datasets of robust long-term changes in human demography constitutes a major challenge for archaeology. One approach is to use the distribution of summed radiocarbon-age probabilities to infer long-term population dynamics (i.e. palaeodemography). However, these can often be biased by preservation potential, site taphonomy or researcher priorities among other aspects, all of which require large datasets to resolve adequately. For this report, we have created such a dataset for the South-Central Andes (16°-25°S), here termed the South Central Andes Radiocarbon (SCAR) database. SCAR spans the last 15,000 years and incorporates ∼1700 14C-dates from 519 archeological sites reported across an extreme bioclimatic gradient that includes the hyperarid coastal Atacama Desert and adjacent cold, high-elevation Altiplano. Among the possible methodological biases, we first evaluated those related to calibration procedures. Otherwise, changes in summed probability curves show no other relevant biases except for possible research interest/priorities that could be responsible for the gaps in the record from the Bolivian altiplano. Our temporally continuous time-series indicates that prehispanic populations exhibited significant demographic changes during the last 13,100calBP. Except for coastal populations; most regions show strongly coordinated demographic fluctuations that follow the same major patterns. Thus, we identified two broad scale population events across the South-Central Andes (Atacama inland, Bolivian Altiplano) from 13,100-4000calBP and then from 4000calBP to the present. In contrast, the Atacama coastal records suggest a different and more variable occupation pattern over the last 13,460calBP, which could be driven by the interaction with oceanographic processes (i.e. upwelling). A widespread major decline at 700calBP clearly predates the Spanish colonization and occurs in all of our regions. This widespread decline does not appear to be due to methodological biases, and suggests that a population crash occurred before European occupation. Overall, the SCAR database constitutes a valuable proxy for establishing the long-term dynamics of prehistoric societies that inhabited the western Andean slope. Time-series analyses that use SCAR will shed new light on the demographic and cultural dynamics at different spatial-scales, and help clarify the processes involved in the migrational trajectories and cultural evolution of the peoples that inhabited the South-Central Andes over the last 15,000 years. | |
| Tree-fall gaps and patterns of tree recruitment and growth in Andean old-growth forests in south-central Chile | Bosque | González, M.; Donoso, P.; Szejner, P. | 2015 | Servicios Ecosistémicos | 10.4067/S0717-92002015000300006 | http://www.scielo.cl/pdf/bosque/v36n3/art06.pdf | 383–394 | Vol: 36 Issue: 3 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Canopy gaps have been recognized as an important process in the regeneration dynamics of Andean old-growth forests (ca. 40º S). The objectives of the study were to determine main tree-fall gap attributes and to assess tree recruitment and growth patterns in tree-fall gaps of two mid-elevation Andean old-growth forests. We measured the canopy and expanded area of each gap, and for the gap-maker species we measured its diameter at breast height (dbh), felling direction and type of treefall. In each gap, tree seedlings, saplings and bamboo culms were counted in subplots. Increment cores of potential successors were obtained to examine growth patterns. There was a larger area in canopy gaps in NF than in STF (25.8 vs. 11.9 %). Expanded gaps were on average larger in NF than in STF (547 vs. 440 m2 ). Most gaps were originated by wind-snap and upturned root-plates of all the major tree species (Laureliopsis philippiana, Saxegothaea conspicua and Dasyphyllum diacanthoides, and Nothofagus dombeyi in NF). The understory species Chusquea culeou was an important competitor in gaps, especially in STF where the bamboo was more effective inhibiting the recruitment of tree seedlings. The successful recruitment of shade-tolerant tree species beneath endogenous tree-fall gaps indicates that these species follow a gap-phase regeneration mode through which –after several growth releases- they can reach the main canopy. These studies could offer valuable insights for the urgently required restoration and management of Andean old-growth forests. |
| Large fires in the Andean Araucaria forests: when a natural ecological process becomes a threat | Oryx | González, M.; Lara, A. | 2015 | Servicios Ecosistémicos | 10.1017/S0030605315000599 | http://journals.cambridge.org/abstract_S0030605315000599 | 394-394 | Vol: 49 Issue: 3 | 0030-6053 | Thomson Reuters ISI (SCIE) | English | The fire season of 2014–2015 in Chile has been one of the worst of the last 50 years, with large and simultaneous fires affecting vast areas of Andean Araucaria–Nothofagus forests in several national parks, forest reserves and private properties. The worst-affected protected areas are China Muerta and Malleco National Reserves, and Conguillío and Tolhuaca National Parks, with an estimated total area of.12,000 ha burned. In 2002 fires burned.20,000 ha, af- fecting mostly the same protected areas and other private land covered by Araucaria forests, with c. 30 and 60%of the total area of Malleco National Reserve and Tolhuaca National Park burned, respectively. As then, the 2014–2015 fires have stirred public, political and scientific concern. | |
| Fire, logging and establishment patterns of second-growth forests in south-central Chile: implications for their management and restoration | Ciencia e investigación agraria | González, M.; Szejner, P.; Donoso, P.; Salas, C. | 2015 | Servicios Ecosistémicos | 10.4067/S0718-16202015000300011 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202015000300011&lng=en&nrm=iso&tlng=en http://rcia.uc.cl/index.php/rcia/article/view/1580/1178 | 11–11 | Vol: 42 Issue: 3 | 0718-1620 | Thomson Reuters ISI (ESCI) | All Open Access; Hybrid Gold Open Access | English | Second-growth forests represent the greatest potential resource for forest management and large-scale ecological restoration in many regions. In south-central Chile, second-growth forests include those dominated by Nothofagus obliqua , N. dombeyi , Drimys winteri , and a mixture of evergreen species, especially hardwoods. This article examines the influence of fire and logging on the establishment patterns and development of second-growth forests in south-central Chile. We characterize the size structure and composition of these four types of forests with sampling plots. The identification of the type of disturbance and its date of occurrence was determined from evidence such as fire scars and even-aged pulses of tree establishment. The size, structure and species composition of these forests indicate an intermediate state of development with an average density and basal area ranging from 1294 to 5038 trees ha -1 and from 59 to 85 m 2 ha -1 , respectively. Logging and/or devastating fires that occurred in the early decades of the 1900s promoted the relatively rapid establishment and growth of pioneer species ( Nothofagus obliqua, N. dombeyi, D. winteri ). In the Mixed Evergreen second-growth forests, mid-shade or shade tolerant species (e.g., Gevuina avellana, Eucryphia cordifolia, Amomyrtus luma, and A. meli ) became established mostly through vegetative sprouting. Fires and logging have been pervasive factors in determining the structural and compositional uniformity of the native forests of south-central Chile. Ecological restoration at a landscape level, either by ecological processes (i.e., a reduction in fire frequency) and/or the structure and composition of second-growth forests, provide a relevant approach to accelerating the generation of attributes of old-growth forests, therefore meeting manifold societal demands for forest goods and services. Los bosques secundarios representan el mayor recurso forestal para el manejo y la restauración de gran escala en muchas regiones del mundo. En el centro-sur de Chile los bosques secundarios están dominados por Nothofagus obliqua , N. dombeyi , D. winteri , y Siempreverde mixtos. El presente artículo examina la influencia del fuego y tala en los patrones de establecimiento y desarrollo de bosques secundarios de la región centro-sur de Chile. Para la caracterización de la estructura y composición de cada bosque secundario se seleccionaron rodales representativos estableciendo 4-6 parcelas de 900 m 2 . El tipo de disturbio y su fecha de ocurrencia fue establecido a través de evidencias tales como cicatrices de fuego y pulsos de establecimiento de árboles. La estructura de tamaños y composición indican un estado de desarrollo intermedio o de reiniciación del sotobosque presentando en promedio una densidad y área basal que varía entre 1294 y 5038 árboles ha -1 y entre 59 y 85 m 2 ha -1 , respectivamente. Incendios de gran severidad y/o madereo ocurridos en las primeras décadas de los 1900 promovieron un rápido establecimiento de las principales especies pioneras ( Nothofagus obliqua, N. dombeyi, D. winteri ). En los bosques secundarios Siempreverde mixtos, el establecimiento de especies tolerantes o semi-tolerantes a la sombra (ej., Gevuina avellana, Eucryphia cordifolia ), fue principalmente por rebrotes vegetativos. El fuego y madereo han sido agentes clave en determinar la uniformidad estructural y composicional de los bosques nativos del centro-sur de Chile. La restauración ecológica a escala de paisaje, tanto de procesos ecológicos (frecuencia incendios) como de la estructura y composición de los bosques secundarios, ofrece una relevante aproximación para acelerar la generación de atributos de bosques antiguos que satisfagan los múltiples bienes y servicios ecosistémicos demandados por la sociedad. |
| Analysis and optimal design of air quality monitoring networks using a variational approach | Tellus B: Chemical and Physical Meteorology | Henriquez, A.; Osses, A.; Gallardo, L.; Diaz Resquin, M. | 2015 | Modelación y Sistemas de Observación | 10.3402/tellusb.v67.25385 | http://www.tellusb.net/index.php/tellusb/article/view/25385 | art25385 | Vol: 67 Issue: 1 | 0280-6509 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Air quality networks need revision and optimisation as instruments and network requirements, both scientific and societal, evolve over time. Assessing and optimising the information content of a monitoring network is a non-trivial problem. Here, we introduce a methodology formulated in a variational framework using an air quality model to simulate the dispersion of carbon monoxide (CO) as a passive tracer at the city scale.Weaddress the specific case of adding or removing stations, and the more general situation of optimally distributing a given number of stations in a domain taking into account transport patterns and spatial factors such as population density and emission patterns.Weconsider three quality indicators: precision gain, information gain and degrees of freedom for a signal. These metrics are all functions of the singular values of the sensitivity matrix that links emissions and observations in the variational framework.Weillustrate the application of the methodology in the case of Santiago (33.58S, 70.58W, 500ma.s.l.), a city of ca. 7 million inhabitants with significant pollution levels. Wedeem information gain as the best of the above indicators for this case.Wethen quantify the actual evolution of Santiago’s network and compare it with the optimal configuration suggested by our methodology and with results previously obtained using a statistical approach. The application is restricted to diurnal and summer conditions, for which the dispersion model shows a good agreement with observations. The current method offers advantages in that it allows extending a network to include new sites, and it explicitly considers the effects of dispersion patterns, and desired weighting functions such as emission fluxes and population density. We find that Santiago’s air quality has improved two-fold since 1988, regarding CO under diurnal summer conditions. Still, according to our results, the current configuration could be improved by integrating more suburban stations in the southwest of the basin. |
| Vegetation and climate change, fire-regime shifts and volcanic disturbance in Chiloé Continental (43°S) during the last 10,000 years | Quaternary Science Reviews | Henríquez, W.; Moreno, P.; Alloway, B.; Villarosa, G. | 2015 | Dinámica del Clima | 10.1016/j.quascirev.2015.06.017 | http://www.sciencedirect.com/science/article/pii/S0277379115300263 http://www.scopus.com/inward/record.url?eid=2-s2.0-84936875083&partnerID=tZOtx3y1 | 158–167 | Vol: 123 | 0277-3791 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Disentangling the roles of paleofires and explosive volcanism from climatic drivers of past vegetation change is a subject insufficiently addressed in the paleoecological literature. The coastal region of the Chiloé Continental sector of northwestern Patagonia is ideal in this regard considering its proximity to active eruptive centers and the possibility of establishing comparisons with more distal, upwind sites where volcanic influence is minimal. Here we present a fine-resolution pollen and macroscopic charcoal record from Lago Teo with the aim of documenting the local vegetation and climate history, and assessing the role of disturbance regimes as drivers of vegetation change during the last ∼10,000 years. The Lago Teo record shows a conspicuous warm/dry interval between ∼7500 and 10,000 cal yrs BP followed by a cooling trend and increase in precipitation that has persisted until the present, in agreement with previous studies in the region and interpretations of past southern westerly wind activity at multi-millennial scales. The presence of 26 tephras throughout the record allows examination of the relationship between explosive volcanism and vegetation change under contrasting climatic states of the Holocene. We found consistent statistically significant increases in Tepualia stipularis after tephra deposition over the last 10,000 years, in Eucryphia/Caldcluvia between 7500 and 10,000 cal yrs BP and in Hydrangea over the last 7500 years. Our results indicate a primary role of climate change as driver of long-term vegetation change and as a modulator of vegetation responses to volcanic disturbance at multidecadal and centennial timescales. |
| Characterization of the 1970s climate shift in South America | International Journal of Climatology | Jacques-Coper, M.; Garreaud, R. | 2015 | Dinámica del Clima | 10.1002/joc.4120 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84939471539&partnerID=tZOtx3y1 | 2164–2179 | Vol: 35 Issue: 8 | 0899-8418 | Thomson Reuters ISI (SCIE) | English | The 1976-1977 cold-to-warm sea surface temperature (SST) shift in the tropical Pacific Ocean, which has been associated with a phase change of the Pacific Decadal Oscillation (PDO) index, separated a 'La Niña-like' decadal regime from an 'El Niño-like' one. In this article, we analyse the differences of mean of annual and austral-summer (DJF) temperature, precipitation, and sea-level pressure (SLP) over South America (SA) between 1961-1973 and 1978-1990, and explore the occurrence of significant shifts in their time series. Our sources are instrumental records, gridded interpolated data, and reanalyses. Although major regional differences in the intensity of the signal are detected, the climate shift is identified in all variables. In the mid-1970s at annual level, reanalysis SLP data reveal the onset of a step-like anticyclonic circulation anomaly in the southern tip of SA and an abrupt weakening of the Southeast Pacific Subtropical Anticyclone (SEPA). This latter feature may have partly induced the rapid warming observed along the tropical-extratropical west coast of the continent through the weakening of the cold Humboldt current system. An abrupt warming was also detected in surface air temperature (SAT) composites located along the coast of the northern part of SA and in Southeastern SA (SESA). During summer, we found a particularly conspicuous shift-like warming over Southern South America (SSA, comprising Patagonia). Besides, a shift-like increase (decrease) in annual mean precipitation is observed over Central Argentina and in the tropics, to the south (north) of 10°S. In line with previous studies, we conclude that both the interannual (El Niño-Southern Oscillation, ENSO) and the interdecadal (PDO) variability modes seem to have had an incidence in the manifestation of the 1970s climate shift, and that its magnitude appears to be unprecedented during the 20th century, as shown in particular by century-long SAT composites from northern Chile and SSA. | |
| Dust fluxes and iron fertilization in Holocene and Last Glacial Maximum climates | Geophysical Research Letters | Lambert, F.; Tagliabue, A.; Shaffer, G.; Lamy, F.; Winckler, G.; Farías, L.; Gallardo, L.; De Pol-Holz, R. | 2015 | Biogeoquímica; Modelación y Sistemas de Observación | 10.1002/2015GL064250 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84938971959&partnerID=tZOtx3y1 | 6014–6023 | Vol: 42 Issue: 14 | 0094-8276 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Mineral dust aerosols play a major role in present and past climates. To date, we rely on climate models for estimates of dust fluxes to calculate the impact of airborne micronutrients on biogeochemical cycles. Here we provide a new global dust flux data set for Holocene and Last Glacial Maximum (LGM) conditions based on observational data. A comparison with dust flux simulations highlights regional differences between observations and models. By forcing a biogeochemical model with our new data set and using this model's results to guide a millennial-scale Earth System Model simulation, we calculate the impact of enhanced glacial oceanic iron deposition on the LGM-Holocene carbon cycle. On centennial timescales, the higher LGM dust deposition results in a weak reduction of <10ppm in atmospheric CO2 due to enhanced efficiency of the biological pump. This is followed by a further ∼10ppm reduction over millennial timescales due to greater carbon burial and carbonate compensation. |
| A review of the bipolar see–saw from synchronized and high resolution ice core water stable isotope records from Greenland and East Antarctica | Quaternary Science Reviews | Landais, A.; Masson-Delmotte, V.; Stenni, B.; Selmo, E.; Roche, D.; Jouzel, J.; Lambert, F.; Guillevic, M.; Bazin, L.; Arzel, O.; Vinther, B.; Gkinis, V.; Popp, T. | 2015 | Modelación y Sistemas de Observación | 10.1016/j.quascirev.2015.01.031 | http://www.sciencedirect.com/science/article/pii/S0277379115000554 | 18–32 | Vol: 114 | 0277-3791 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Numerous ice core records are now available that cover the Last Glacial cycle both in Greenland and in Antarctica. Recent developments in coherent ice core chronologies now enable us to depict with a precision of a few centuries the relationship between climate records in Greenland and Antarctica over the millennial scale variability of the Last Glacial period. Stacks of Greenland and Antarctic water isotopic records nicely illustrate a seesaw pattern with the abrupt warming in Greenland being concomitant with the beginning of the cooling in Antarctica at the Antarctic Isotopic Maximum (AIM). In addition, from the precise estimate of chronological error bars and additional high resolution measurements performed on the EDC and TALDICE ice cores, we show that the seesaw pattern does not explain the regional variability in Antarctic records with clear two step structures occurring during the warming phase of AIM 8 and 12. Our Antarctic high resolution data also suggest possible teleconnections between changes in low latitude atmospheric circulation and Antarctic without any Greenland temperature fingerprint. |
| Reconstructing streamflow variation of the Baker River from tree-rings in Northern Patagonia since 1765 | Journal of Hydrology | Lara, A.; Bahamondez, A.; González-Reyes, A.; Muñoz, A.; Cuq, E.; Ruiz-Gómez, C. | 2015 | Servicios Ecosistémicos | 10.1016/j.jhydrol.2014.12.007 | http://www.sciencedirect.com/science/article/pii/S0022169414010099 | 511–523 | Vol: 529 | 0022-1694 | Thomson Reuters ISI (SCIE) | English | The understanding of the long-term variation of large rivers streamflow with a high economic and social relevance is necessary in order to improve the planning and management of water resources in different regions of the world. The Baker River has the highest mean discharge of those draining both slopes of the Andes South of 20°S and it is among the six rivers with the highest mean streamflow in the Pacific domain of South America (1100m3s-1 at its outlet). It drains an international basin of 29,000km2 shared by Chile and Argentina and has a high ecologic and economic value including conservation, tourism, recreational fishing, and projected hydropower. This study reconstructs the austral summer - early fall (January-April) streamflow for the Baker River from Nothofagus pumilio tree-rings for the period 1765-2004. Summer streamflow represents 45.2% of the annual discharge. The regression model for the period (1961-2004) explains 54% of the variance of the Baker River streamflow (R2adj=0.54). The most significant temporal pattern in the record is the sustained decline since the 1980s (τ=-0.633, p=1.0144*10-5 for the 1985-2004 period), which is unprecedented since 1765. The Correlation of the Baker streamflow with the November-April observed Southern Annular Mode (SAM) is significant (1961-2004, r=-0.55, p | |
| Anillos de crecimiento de Austrocedrus chilensis: un archivo natural del cambio climático | Revista del Jardin Botánico Chagual | LeQuesne, C.; Rojas, M.; Christie, D. | 2015 | Dinámica del Clima | http://www.jardinbotanicochagual.cl | 31-35 | Vol: 12 | The International Journal of Climate Change: Impacts and Responses | Anillos de crecimiento y registro del clima del pasado | ||||
| Buffer effects of streamside native forests on water provision in watersheds dominated by exotic forest plantations | Ecohydrology | Little, C.; Cuevas, J.; Lara, A.; Pino, M.; Schoenholtz, S. | 2015 | Servicios Ecosistémicos | 10.1002/eco.1575 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84945264768&partnerID=tZOtx3y1 | 1205–1217 | Vol: 8 Issue: 7 | 1936-0584 | Thomson Reuters ISI (SCIE) | English | The Valdivian rainforest ecoregion in Chile (35°-48°S) has a high conservation priority worldwide. These forests are also keys for social welfare as a result of their supply of timber as well as ecosystem services. Forests in the ecoregion have been extensively converted to fast growing Pinus radiata and Eucalyptus spp. plantations for timber production promoted by public policies and timber companies. This study describes the results of detailed measurements of hydrology and stream water chemistry in eight small watersheds in south central Chile, subjected to replacement of native temperate rainforest by exotic Eucalyptus plantations. In this system, watersheds have streamside buffers of native forest (SNFW) with varying widths. Results indicate that retention of SNFW counteracts hydrologic effects of Eucalyptus plantations, which are widely known to reduce water yields. A 1.4% rate of increase of the run-off coefficient for each metre of increase of SNFW was observed. In addition, a decrease in the concentrations of total nitrogen, dissolved inorganic nitrogen (DIN), nitrate-N, and different sized fractions of particulate organic matter were found in streams draining these plantations as a function of increasing SNFW. Streamside buffer widths of 17-22m for total nitrogen and DIN concentrations and ≥36m for sediments were required to provide comparable values to reference watersheds (100% native forest). The findings from this study suggest that SNFW may significantly reduce adverse effects from exotic species forestry plantations on water provision in an area of south central Chile where exotic forest plantations are rapidly expanding. © 2015 John Wiley | |
| Different times, same story: Native forest loss and landscape homogenization in three physiographical areas of south-central of Chile | Applied Geography | Miranda, A.; Altamirano, A.; Cayuela, L.; Pincheira, F.; Lara, A. | 2015 | Servicios Ecosistémicos | 10.1016/j.apgeog.2015.02.016 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84928324890&partnerID=tZOtx3y1 http://www.sciencedirect.com/science/article/pii/S0143622815000478 | 20–28 | Vol: 60 | 0143-6228 | Thomson Reuters ISI (SSCI) | English | Temperate forest represents the smallest area among the main world's forest biomes, but is one of those most threatened by forest loss. Chile contains most of the temperate forest in South America and more than half of the temperate forest in the southern hemisphere. Chilean temperate forest is considered to be one of the world's biodiversity hotspots. In this study we assessed the rate of land use and land cover (LULC) change over time, identified the main LULCs replacing native forest, and described how changes have evolved in contrasting physiographical conditions and through different historical phases of the landscape over the last 40 years. To achieve this, we analysed LULC change with particular focus on forest cover in three areas representing different physiographical conditions and histories of human occupation in the Araucanía Region of Chile, namely the Central Valley, the Coastal range, and the Andean range. We found substantial differences in temporal and intra-regional patterns of forest loss and LULC change. In the Central Valley, forest loss started long ago, and the area occupied by native forest nowadays is less than 5% of the landscape. In the Coastal range, rapid land cover change has taken place since 1973, with an increasing rate of forest loss over time. We detected a similar but less intense pattern in the forests of the Andean range. Overall, the general pattern points to a process of landscape homogenization in all three physiographical areas. Exotic tree plantations have spread over large geographical areas, becoming the dominant land cover. Land cover change in the Araucanía Region reflects a model of change in which areas with better environmental conditions and accessibility are occupied first for productive activities. As the availability of suitable areas for the expansion of productive activities diminishes, these activities start to move into physiographical areas which were previously “protected” by adverse environmental conditions or poor accessibility. This model of production growth could lead to the complete deforestation of areas outside national protected areas, and other areas which still remain inaccessible due to technological restrictions on exploitation. | |
| Pollution and its Impacts on the South American Cryosphere | Earth's Future | Molina, L.; Gallardo, L.; Andrade, M.; Baumgardner, D.; Borbor-Córdova, M.; Bórquez, R.; Casassa, G.; Cereceda-Balic, F.; Dawidowski, L.; Garreaud, R.; Huneeus, N.; Lambert, F.; McCarty, J.; Mc Phee, J.; Mena-Carrasco, M.; Raga, G.; Schmitt, C.; Schwarz, J. | 2015 | Dimensión Humana; Dinámica del Clima; Modelación y Sistemas de Observación | 10.1002/2015EF000311 | http://onlinelibrary.wiley.com/doi/10.1002/2015EF000311/abstract | 345-369 | Vol: 3 Issue: 12 | 2328-4277 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | This article is a review of the science goals and activities initiated within the framework of the Pollution and its Impacts on the South American Cryosphere (PISAC) initiative. Air pollution associated with biomass burning and urban emissions affects extensive areas of South America. We focus on black carbon (BC) aerosol and its impacts on air quality, water availability, and climate, with an emphasis on the Andean cryosphere. BC is one of the key short-lived climate pollutants that is a topic of growing interest for near-term mitigation of these issues. Limited scientific evidence indicates that the Andean cryosphere has already responded to climate change with receding glaciers and snow cover, which directly affect water resources, agriculture, and energy production in the Andean region of South America. Despite the paucity of systematic observations along the Andes, a few studies have detected BC on snow and glaciers in the Andes. These, in addition to existing and projected emissions and weather patterns, suggest a possible contribution of BC to the observed retreat of the Andean cryosphere. Here we provide an overview of the current understanding of these issues from scientific and policy perspectives, and propose strategic expansions to the relevant measurement infrastructure in the region. |
| La Gobernanza del Cambio Climático. Propuesta de Marco Legal para abordar el Cambio Climático en Chile | Moraga, P.; Araya, G. | 2015 | Dimensión Humana | https://www.cr2.cl/wp-content/uploads/2018/03/Gobernanza_CambioClimatico.pdf | 54 | En un año crucial para las negociaciones climáticas internacionales, resulta fundamental disponer de la mejor información para que tomadores de decisión, y público en general, puedan conocer el estado de la institucionalidad y la política pública del cambio climático en el País. El informe “La Gobernanza del Cambio Climático en Chile”, enmarcado en el proyecto “Propuesta de marco legal e institucional para abordar el cambio climático”, financiado por la Embajada Británica en Chile y patrocinado por el Ministerio del Medio Ambiente, responde a dicha necesidad, ofreciendo una completa y actualizada descripción en esta materia, a través del análisis del marco jurídico que la regula y de la política pública desarrollada en este ámbito. El informe cuenta con dos capítulos referidos a las “bases de la política de cambio climático” y a su “implementación”. El primero contiene un análisis de los primeros compromisos internacionales suscritos por Chile y de la institucionalidad creada en este ámbito. Destacan a este respecto la referencia a la Primera Comunicación Nacional presentada a la Secretaría de la Convención. Luego, el estudio aborda la Segunda Comunicación Nacional, el compromiso voluntario de reducción de emisiones surgido tras el Acuerdo de Copenhague del año 2009, la elaboración de los Informes Bienales de Actualización, y la Contribución Nacional Tentativa. Por último se aborda un análisis del Plan Nacional de Cambio Climático 2008-2012 y los diferentes planes de adaptación vigentes y en preparación. Asimismo, se revisan los diferentes diseños institucionales que se han establecido a la fecha, con énfasis en las instituciones gubernamentales involucradas y las respectivas competencias asignadas. |
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| Análisis comparativo de legislación de cambio climático | Moraga, P.; Meckievi, S. | 2015 | https://www.cr2.cl/wp-content/uploads/2015/08/Derecho_comparado.pdf | 106 | |||||||||
| Radiocarbon chronology of the last glacial maximum and its termination in northwestern Patagonia | Quaternary Science Reviews | Moreno, P.; Denton, G.; Moreno, H.; Lowell, T.; Putnam, A.; Kaplan, M. | 2015 | Dinámica del Clima | 10.1016/j.quascirev.2015.05.027 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84936771311&partnerID=tZOtx3y1 http://linkinghub.elsevier.com/retrieve/pii/S0277379115300044 | 233–249 | Vol: 122 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | We examine the timing and magnitude of the last glacial maximum (LGM) and the last glacial termination (LGT) in northwestern Patagonia, situated in the middle latitudes of South America. Our data indicate that the main phase of the LGT began with abrupt warm pulses at 17,800 and 17,100calyrs BP, accompanied by rapid establishment of evergreen temperate rainforests and extensive deglaciation of the Andes within 1000 years. This response shows that South American middle-latitude temperatures had approached average interglacial values by 16,800calyrs BP. The temperature rise in northwestern Patagonia coincides with the beginning of major warming and glacier recession in the Southern Alps of New Zealand at southern mid-latitudes on the opposite side of the Pacific Ocean. From this correspondence, the warming that began at 17,800calyrs BP appears to have been widespread in middle latitudes of the Southern Hemisphere, accounting for at least 75% of the total temperature recovery from the LGM to the Holocene. Moreover, this warming pulse is coeval with the first half of the Heinrich Stadial 1 (HS1) in the North Atlantic region. HS1 featured a decline of North Atlantic meridional overturning circulation, a southward shift of the westerly wind belt in both hemispheres and of the Intertropical Convergence Zone, as well as a weakening of the Asian monsoon. Along with the initiating trigger, identifying the mechanisms whereby these opposing climate signals in the two polar hemispheres interacted -whether through an oceanic or an atmospheric bipolar seesaw, or both- lies at the heart of understanding the LGT. | |
| Mapping of ecosystem services: Missing links between purposes and procedures | Ecosystem Services | Nahuelhual, L.; Laterra, P.; Villarino, S.; Mastrángelo, M.; Carmona, A.; Jaramillo, A.; Barral, P.; Burgos, N. | 2015 | Dimensión Humana | 10.1016/j.ecoser.2015.03.005 | http://www.sciencedirect.com/science/article/pii/S2212041615000340 | 162-172 | Vol: 13 | 2212-0416 | Thomson Reuters ISI (SCIE; SSCI) | All Open Access; Green Open Access | English | The literature on ecosystem services mapping presents a diversity of procedures whose consistency might question the reliability of maps for decision-making. This study aims at analyzing the correspondence between the purpose of maps (e.g. land use planning) and the procedures used for mapping (e.g. benefit transfer, ecological transfer). Fifty scientific studies published between 2005 and 2012 were selected and analyzed according to 19 variables, applying independence tests over contingency tables, ANOVA and regression analysis. The results show that most studies declared a decision-making purpose (82%), which in 50% of the cases, was land use planning. Only few relationships were found between variables selected to describe the purpose of the maps and those selected to describe the mapping procedures. Thus for example, maps aimed at supporting land use planning did not include any level of stakeholder participation or scenario analysis, as it would have been expected given this purpose. Likewise, maps were based on either economic value or biophysical transfers, regardless of the spatial and temporal scales of mapping. This generally weak relation between map׳s purposes with the used procedures could explain the still restricted incidence of ES on decision-making by limiting the transmission, comparison and synthesis of results. |
| Facing unprecedented drying of the Central Andes? Precipitation variability over the period AD 1000–2100 | Environmental Research Letters | Neukom, R.; Rohrer, M.; Calanca, P.; Salzmann, N.; Huggel, C.; Acuña, D.; Christie, D.; Morales, M. | 2015 | Dinámica del Clima | 10.1088/1748-9326/10/8/084017 | http://iopscience.iop.org/article/10.1088/1748-9326/10/8/084017 | art084017 | Vol: 10 Issue: 8 | 1748-9326 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Projected future trends in water availability are associated with large uncertainties in many regions of the globe. In mountain areas with complex topography, climate models have often limited capabilities to adequately simulate the precipitation variability on small spatial scales. Also, their validation is hampered by typically very low station density. In the Central Andes of South America, a semi-arid high-mountain region with strong seasonality, zonal wind in the upper troposphere is a good proxy for interannual precipitation variability. Here, we combine instrumental measurements, reanalysis and paleoclimate data, and a 57-member ensemble of CMIP5 model simulations to assess changes in Central Andes precipitation over the period AD 1000–2100. This new database allows us to put future projections of precipitation into a previously missing multi-centennial and pre-industrial context. Our results confirm the relationship between regional summer precipitation and 200 hPa zonal wind in the Central Andes, with stronger Westerly winds leading to decreased precipitation. The period of instrumental coverage (1965–2010) is slightly dryer compared to pre-industrial times as represented by control simulations, simulations from the past Millennium, ice core data from Quelccaya ice cap and a tree-ring based precipitation reconstruction. The model ensemble identifies a clear reduction in precipitation already in the early 21st century: the 10 year running mean model uncertainty range (ensemble 16–84% spread) is continuously above the pre-industrial mean after AD 2023 (AD 2028) until the end of the 21st century in the RCP2.6 (RCP8.5) emission scenario. Average precipitation over AD 2071–2100 is outside the range of natural pre-industrial variability in 47 of the 57 model simulations for both emission scenarios. The ensemble median fraction of dry years (defined by the 5th percentile in pre-industrial conditions) is projected to increase by a factor of 4 until 2071–2100 in the RCP8.5 scenario. Even under the strong reduction of greenhouse gas emissions projected by the RCP2.6 scenario, the Central Andes will experience a reduction in precipitation outside pre-industrial natural variability. This is of concern for the Central Andes, because society and economy are highly vulnerable to changes in the hydrological cycle and already have to face decreases in fresh water availability caused by glacier retreat. |
| Chile Confronts its Environmental Health Future After 25 Years of Accelerated Growth | Annals of Global Health | Pino, P.; Iglesias, V.; Garreaud, R.; Cortés, S.; Canals, M.; Folch, W.; Burgos, S.; Levy, K.; Naeher, L.; Steenland, K. | 2015 | Dinámica del Clima | 10.1016/j.aogh.2015.06.008 | http://www.ncbi.nlm.nih.gov/pubmed/26615070 | 354–367 | Vol: 81 Issue: 3 | 2214-9996 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | BACKGROUND: Chile has recently been reclassified by the World Bank from an upper-middle-income country to a high-income country. There has been great progress in the last 20 to 30 years in relation to air and water pollution in Chile. Yet after 25 years of unrestrained growth, there remain clear challenges posed by air and water pollution, as well as climate change. OBJECTIVE: The aim of this study was to review environmental health in Chile. METHODS: In late 2013, a 3-day workshop on environmental health was held in Santiago, Chile, bringing together researchers and government policymakers. As a follow-up to that workshop, here we review the progress made in environmental health in the past 20 to 30 years and discuss the challenges of the future. We focus on air and water pollution and climate change, which we believe are among the most important areas of environmental health in Chile. RESULTS: Air pollution in some cities remains among the highest in the continent. Potable water is generally available, but weak state supervision has led to serious outbreaks of infectious disease and ongoing issues with arsenic exposure in some regions. Climate change modeling in Chile is quite sophisticated, and a number of the impacts of climate change can be reasonably predicted in terms of which areas of the country are most likely to be affected by increased temperature and decreased availability of water, as well as expansion of vector territory. Some health effects, including changes in vector-borne diseases and excess heat mortality, can be predicted. However, there has yet to be an integration of such research with government planning. CONCLUSIONS: Although great progress has been made, currently there are a number of problems. We suspect that the Chilean experience in environmental health may be of some use for other Latin American countries with rapid economic development. |
| The Atacama Surface Solar Maximum | Bulletin of the American Meteorological Society | Rondanelli, R.; Molina, A.; Falvey, M. | 2015 | Biogeoquímica | 10.1175/BAMS-D-13-00175.1 | http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-13-00175.1 | 405–418 | Vol: 96 Issue: 3 | 0003-0007 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | We have presented a descriptive analysis showing a suite of different global products that combine information from models and satellites to provide the global distribution of surface total solar radiation as well as the distribution of the main substances that explain the atmospheric extinction of solar radiation reaching the surface. Latitude, elevation, cloud fraction, water vapor, and aerosols have a first-order influence on the distribution of surface solar radiation over the planet, and no single factor explains the combined distribution. The most likely location of the total solar radiation over the surface of the planet is on the pre-Andean Domeyko Cordillera, a mountain range with elevations between 3,500 and 5,000 m. The regional climate of the Atacama is such that extremely low values of water vapor, cloud cover, ozone, and aerosols concur in this region. The atmospheric transparency in the visible and infrared provided by these conditions, together with a relatively high elevation and low latitude, conspire to produce a region where mean total radiation values exceed 300 W m-2. According to a semiempirical model for surface solar radiation that takes into account extinction by gases, clouds, aerosols, and the effect of topography, the maximum is about 310 ± 15 W m-2, although for individual years, especially those with dry summertime Altiplano conditions, the solar maximum should be located in the Altiplano region near to the Chajnantor Plateau. The delicate combination of elements that concurs in the Atacama region still justifies the increase in observational capabilities of solar radiation and atmospheric composition as it was first devised and executed by the pioneers of solar research in Mount Montezuma in the early twentieth century. |
| Effect of Nearby Forest Fires on Ground Level Ozone Concentrations in Santiago, Chile | Atmosphere | Rubio, M.; Lissi, E.; Gramsch, E.; Garreaud, R. | 2015 | Dinámica del Clima | 10.3390/atmos6121838 | http://www.mdpi.com/2073-4433/6/12/1838 http://www.mdpi.com/2073-4433/6/12/1838/htm | 1926–1938 | Vol: 6 Issue: 12 | 2073-4433 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | On 4 and 8 January 2014, at the height of the austral summer, intense wildfires in forests and dry pastures occurred in the Melipilla sector, located about 70 km to the southwest of Santiago, the Chilean capital, affecting more than 6 million inhabitants. Low level winds transported the forest fire plume towards Santiago causing a striking decrease in visibility and a marked increase in the concentration of both primary (PM10 and CO) and secondary (Ozone) pollutants in the urban atmosphere. In particular, ozone maximum concentrations in the Santiago basin reached hourly averages well above 80 ppb, the national air quality standard. This ozone increase took place at the three sampling sites considered in the present study. These large values can be explained in terms of high NOx concentrations and NO2/NO ratios in biomass burning emissions. |
| Estado actual de la Restauración ecológica en Chile, perspectivas y desafíos | Anales del Instituto de la Patagonia | Smith-Ramírez, C.; González, M.; Echeverría, C.; Lara, A. | 2015 | Servicios Ecosistémicos | 10.4067/S0718-686X2015000100002 | http://analesdelinstitutodelapatagonia.cl/index.php/analespatagonia/article/view/693 | 11-21 | Vol: 43 Issue: 1 | 0718-686X | SciELO | Spanish | Ecological restoration is a discipline that was born just under 30 years. In Latin America it is in a formation stage, with Chile as one of the countries that has led in some aspects of restoration. The purpose of this paper is to review the state of the art of Ecological Restoration (ER) in Chile. Specifically we aim to: i) a brief compilation of the first actions of ecological restoration developed in the country; ii) to identify the ecological restoration of forest ecosystems that have been or are being implemented; iii) to identify the organizations that have been involved; and iv) to outline the main challenges and opportunities of ER in the country. We found about 60 ER initiatives in the country, that are being developed by NGOs, government, forest companies and universities. Despite being many initiatives, the area covered by each one is rather small. However, there are commitments to expand it considerably. ER is increasingly beingtaught in universities. The challenges aimed primarily at generating a National and Regional ER Plans that includes various ways of funding. | |
| Aggradation and carbonate accumulation of Holocene Norwegian cold-water coral reefs | Sedimentology | Titschack, J.; Baum, D.; de Pol-Holz, R.; López Correa, M.; Forster, N.; Flögel, S.; Hebbeln, D.; Freiwald, A. | 2015 | Biogeoquímica | 10.1111/sed.12206 | http://doi.wiley.com/10.1111/sed.12206 | 1873–1898 | Vol: 62 Issue: 7 | 0037-0746 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Cold-water coral ecosystems present common carbonate factories along the Atlantic continental margins, where they can form large reef structures. There is increasing knowledge on their ecology, molecular genetics, environmental controls and threats available. However, information on their carbo-nate production and accumulation is still very limited, even though this information is essential for their evaluation as carbonate sinks. The aim of this study is to provide high-resolution reef aggradation and carbonate accumulation rates for Norwegian cold-water coral reefs from various settings (sunds, inner shelf and shelf margin). Furthermore, it introduces a new approach for the evaluation of the cold-water coral preservation within cold-water coral deposits by computed tomography analysis. This approach allows the differentiation of various kinds of cold-water coral deposits by their macrofossil clast size and orientation signature. The obtained results suggest that preservation of cold-water coral frameworks in living position is favoured by high reef aggradation rates, while preservation of coral rubble prevails by moderate aggradation rates. A high degree of macrofossil fragmentation indicates condensed intervals or unconformities. The observed aggradation rates with up to 1500 cm kyr−1 exhibit the highest rates from cold-water coral reefs so far. Reef aggradation within the studied cores was restricted to the Early and Late Holocene. Available datings of Norwegian cold-water corals support this age pattern for other fjords while, on the shelf, cold-water coral ages are reported additionally from the early Middle Holocene. The obtained mean carbonate accumulation rates of up to 103 g cm−2 kyr−1 exceed previous estimates of cold-water coral reefs by a factor of two to three and by almost one order of magnitude to adjacent sedimentary environments (shelf, slope and deep sea). Only fjord basins locally exhibit carbonate accumulation rates in the range of the cold-water coral reefs. Furthermore, cold-water coral reef carbonate accumulation rates are in the range of tropical reef carbonate accumulation rates. These results clearly suggest the importance of cold-water coral reefs as local, maybe regional to global, carbonate sinks. |
| How Do Surficial Lithic Assemblages Weather in Arid Environments? A Case Study from the Atacama Desert, Northern Chile | Geoarchaeology | Ugalde, P.; Santoro, C.; Gayo, E.; Latorre, C.; Maldonado, S.; De Pol-Holz, R.; Jackson, D. | 2015 | Biogeoquímica | 10.1002/gea.21512 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84936859701&partnerID=tZOtx3y1 http://doi.wiley.com/10.1002/gea.21512 | 352–368 | Vol: 30 Issue: 4 | 0883-6353 | Thomson Reuters ISI (SCIE; AHCI) | English | Archaeological sites composed only of surficial lithics are widespread in arid environments. Numerical dating of such sites is challenging, however, and even establishing a relative chronology can be daunting. One potentially helpful method for assigning relative chronologies is to use lithic weathering, on the assumption that the most weathered artifacts are also the oldest. Yet, few studies have systematically assessed how local environmental processes affect weathering of surficial lithics. Using macroscopic analyses, we compared the weathering of surficial lithic assemblages from seven mid-to-late Holocene archaeological sites sampled from four different microenvironments in the Atacama Desert of northern Chile. Changes in polish, texture, shine, and color were used to establish significant differences in weathering between two kinds of locations: interfluves and canyon sites. Lithics from interfluve sites were moderately to highly weathered by wind and possessed a dark coating, whereas canyon lithics were mildly weathered despite greater exposure to moisture, often lacked indications of eolian abrasion, and lacked dark coatings. Our results show that lithic weathering can be used as a proxy for relative age, but only after considering local environmental factors. The power of such chronologies can be improved by combining archaeological, paleoenvironmental, geomorphological, and taphonomic data. | |
| La observación del problema ambiental en un contexto de diferenciación funcional | Revista Mad | Urquiza, A.; Morales, B. | 2015 | Dimensión Humana | 10.5354/0718-0527.2015.37324 | https://www.revistamad.uchile.cl/index.php/RMAD/article/view/37324 | 64-93 | Issue: 33 | 0718-0527 | Thomson Reuters ISI (ESCI) | El presente trabajo es fruto de una investigación social cualitativa realizada el año 2014 en el marco del Núcleo Interdisciplinario de Estudios Socioambientales de la Universidad de Chile (NIES) y con el apoyo del Centro de Ciencia del Clima y Resiliencia (CR2). La investigación se centra en el problema ambiental desde tres ámbitos sociales: público, privado y conocimiento experto. El estudio identificó la existencia de tres tipos de obstáculos que dificultarían el diálogo entre los actores que son parte de la discusión, así como el tratamiento del problema socioambiental, estos son: obstáculos a nivel de institucionalidad y normativa vigente; obstáculos a nivel del actuar y de las relaciones entre los actores; y obstáculos que se presentan a nivel de los significados asignados al problema. En el presente artículo se abordan los últimos dos tipos de obstáculos desde una perspectiva sistémico constructivista. | ||
| Increased water use efficiency but contrasting tree growth patterns in Fitzroya cupressoides forests of southern Chile during recent decades | Journal of Geophysical Research: Biogeosciences | Urrutia-Jalabert, R.; Malhi, Y.; Barichivich, J.; Lara, A.; Delgado-Huertas, A.; Rodríguez, C.; Cuq, E. | 2015 | Servicios Ecosistémicos | 10.1002/2015JG003098 | http://doi.wiley.com/10.1002/2015JG003098 | 2505–2524 | Vol: 120 Issue: 12 | 0148-0227 | Thomson Reuters ISI (SCIE) | English | Little is known about how old-growth and massive forests are responding to environmental change. We investigated tree-ring growth and carbon isotopes of the long-lived and high biomass Fitzroya cupressoides in two stands growing in contrasting environmental conditions in the Coastal Range (∼300 years old) and Andean Cordilleras (>1500 years old) of southern Chile. The interannual variability in δ13C was assessed for the period 1800–2010, and changes in discrimination and intrinsic water use efficiency (iWUE) were evaluated in relation to changes in climate and tree-ring growth during the last century. 13C discrimination has significantly decreased, and iWUE has increased since the 1900s in both sites. However, these trends in isotopic composition have been accompanied by different growth patterns: decreasing growth rates in the Coastal Range since the 1970s and increasing growth rates in the Andes since the 1900s. Trees growing in the Coastal Range have become more efficient in their use of water, probably due to reduced stomatal conductance caused by increases in CO2 and warming. Trees growing in the Andes have also become more water use efficient, but this has been likely due to increased photosynthetic rates. Fitzroya forests, including particularly old-growth stands, are responding to recent environmental changes, and their response has been site dependent. The growth of forests under a more Mediterranean climate influence and restrictive soil conditions in the Coastal Range has been more negatively affected by current warming and drying; while the growth of old stands in thewet Andes has been positively affected by changes in climate (decreasing cloudiness) and increasing CO2. Permanent monitoring of these endangered forests under ongoing environmental changes is needed in order to reassure the long-term preservation of this millennial-aged species. | |
| The Oldest, Slowest Rainforests in the World? Massive Biomass and Slow Carbon Dynamics of Fitzroya cupressoides Temperate Forests in Southern Chile | PloS one | Urrutia-Jalabert, R.; Malhi, Y.; Lara, A. | 2015 | Servicios Ecosistémicos | 10.1371/journal.pone.0137569 | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0137569 | art0137569 | Vol: 10 Issue: 9 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Old-growth temperate rainforests are, per unit area, the largest and most long-lived stores of carbon in the terrestrial biosphere, but their carbon dynamics have rarely been described. The endangered Fitzroya cupressoides forests of southern South America include stands that are probably the oldest dense forest stands in the world, with long-lived trees and high standing biomass. We assess and compare aboveground biomass, and provide the first estimates of net primary productivity (NPP), carbon allocation and mean wood residence time in medium-age stands in the Alerce Costero National Park (AC) in the Coastal Range and in old-growth forests in the Alerce Andino National Park (AA) in the Andean Cordillera. Aboveground live biomass was 113-114 Mg C ha(-1) and 448-517 Mg C ha(-1) in AC and AA, respectively. Aboveground productivity was 3.35-3.36 Mg C ha(-1) year(-1) in AC and 2.22-2.54 Mg C ha(-1) year(-1) in AA, values generally lower than others reported for temperate wet forests worldwide, mainly due to the low woody growth of Fitzroya. NPP was 4.21-4.24 and 3.78-4.10 Mg C ha(-1) year(-1) in AC and AA, respectively. Estimated mean wood residence time was a minimum of 539-640 years for the whole forest in the Andes and 1368-1393 years for only Fitzroya in this site. Our biomass estimates for the Andes place these ecosystems among the most massive forests in the world. Differences in biomass production between sites seem mostly apparent as differences in allocation rather than productivity. Residence time estimates for Fitzroya are the highest reported for any species and carbon dynamics in these forests are the slowest reported for wet forests worldwide. Although primary productivity is low in Fitzroya forests, they probably act as ongoing biomass carbon sinks on long-term timescales due to their low mortality rates and exceptionally long residence times that allow biomass to be accumulated for millennia. |
| Environmental correlates of stem radius change in the endangered Fitzroya cupressoides forests of southern Chile | Agricultural and Forest Meteorology | Urrutia-Jalabert, R.; Rossi, S.; Deslauriers, A.; Malhi, Y.; Lara, A. | 2015 | Servicios Ecosistémicos | 10.1016/j.agrformet.2014.10.001 | http://www.sciencedirect.com/science/article/pii/S0168192314002524 | 209–221 | Vol: 200 | 0168-1923 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Relationships between environmental factors and stem radius variation at short temporal scales can provide useful information regarding the sensitivity of tree species' productivity to climate change. This study used automatic point dendrometers to assess the relationship between environmental variables and stem radius contraction and increment in ten Fitzroya cupressoides trees growing in two sites, the Coastal Range (Alerce Costero National Park) and the Andean Cordillera (Alerce Andino National Park) of southern Chile. The growing season in each site, determined using stem daily cycle patterns for each month, was longer in the Coastal Range site than in the Andes. Warmer and sunnier conditions were positively related with daytime tree radius contraction in both areas, and relationships were stronger in the Coastal Range site where more pronounced shrinking events were associated with prolonged warm and dry conditions compared to the Andes. Stem increment was positively related with precipitation and humidity in both sites, reflecting the positive effect of water on cell turgidity and consequent enlargement. Relationships between stem radius change and environmental variables considering longer temporal scales (7 to 31 days), confirmed a stronger association with humidity/vapor pressure deficit and precipitation, rather than with temperature. Although Fitzroya grows in particularly wet and cool areas, current and projected drier and warmer summer conditions in southern Chile may have a negative effect on Fitzroya stem increment and carbon accumulation in both sites. This effect would be more critical in the Coastal Range compared with the Andes though, due in part to more limiting soil conditions and less summer precipitation in this area. Long-term research is needed to monitor different aspects of the response of these endangered ecosystems to this additional threat imposed by climate change. |
| Consumption of animals beyond diet in the Atacama Desert, northern Chile (13,000–410BP): Comparing rock art motifs and archaeofaunal records | Journal of Anthropological Archaeology | Valenzuela, D.; Santoro, C.; Capriles, J.; Quinteros, M.; Peredo, R.; Gayo, E.; Montt, I.; Sepúlveda, M. | 2015 | Biogeoquímica | 10.1016/j.jaa.2015.09.004 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84942807642&partnerID=tZOtx3y1 http://www.sciencedirect.com/science/article/pii/S0278416515000872 | 250–265 | Vol: 40 | 0278-4165 | Thomson Reuters ISI (SSCI; AHCI) | All Open Access; Hybrid Gold Open Access | English | The relations between humans and animals extend into socio-cultural aspects that go beyond the mere acquisition of food, meaning that animals constitute cultural resources that fulfill diverse roles in social and cultural systems. Visual images in different media, including rock art, represent one of the ways in which these complex relationships take place. While in the New World few comparative analyses of archaeofaunal and visual data have been addressed, in the Old World these studies have been framed by a dichotomist view between drawn (thought) and consumed (eaten) understanding, both terms as separate and disconnected social realms. This view also structures an abstract, non-pragmatic, rather passive, world drawn in art, against a concrete, practical, active world of consumption. The analysis we present here, based on principles of substantive economy theory, explores the relation between humans and animals in the prehistory of the Atacama Desert (ca. 13,000-410. BP), by comparing visual images of fauna depicted in rock art (engravings and paintings) with archaeofaunal remains from domestic and funerary contexts. The dataset (comprised of 1534 archaeofaunal items and 729 rock art animal motifs from 117 sites) was standardized by calculating the percentage of ubiquity of each animal item per period of time, using Spearman's rank correlation coefficients to identify synchronic and diachronic changes in the relative importance of certain animals consumed. We observed important temporal and contextual variations in the consumption of animals drawn in rock art in the Atacama Desert, and we conclude that they reflect a selection of a wide range of ritual and utilitarian, but not mutually exclusive, functions. In particular, images of camelids emphasized the importance of providing fiber for the creation of textile artifacts and camelid use as pack animals in the caravan trade, both activities that were fundamental in the economy of local societies. |
| Orographic effects of the subtropical and extratropical Andes on upwind precipitating clouds | Journal of Geophysical Research: Atmospheres | Viale, M.; Garreaud, R. | 2015 | Dinámica del Clima | 10.1002/2014JD023014 | http://onlinelibrary.wiley.com/doi/10.1002/2014JD023014/abstract? | 4962-4974 | Vol: 120 Issue: 10 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | The orographic effect of the Andes (30°S–55°S) on upwind precipitating clouds from midlatitude frontal systems is investigated using surface and satellite data. Rain gauges between 33°S and 44°S indicate that annual precipitation increases from the Pacific coast to the windward slopes by a factor of 1.8 ± 0.3. Hourly gauges and instantaneous satellite estimates reveal that the cross-barrier increase in annual precipitation responds to an increase in both the intensity and frequency of precipitation. CloudSat satellite data indicate that orographic effects of the Andes on precipitating ice clouds increase gradually from midlatitudes to subtropics, likely as a result of a reduction of synoptic forcing and an increase of the height of the Andes equatorward. To the south of 40°S, the thickness of clouds slightly decreases from offshore to the Andes. The total ice content increases substantially from the open ocean to the coastal zone (except to the south of 50°S, where there is no much variation over the ocean), and then experience little changes in the cross-mountain direction over the upstream and upslope sectors. Nevertheless, the maximum ice content over the upslope sector is larger and occurs at a lower level than their upwind counterparts. In the subtropics, the offshore clouds contain almost no ice, but the total and maximum ice content significantly increases toward the Andes, with values being much larger than their counterparts over the extratropical Andes. Further, the largest amounts of cloud ice are observed upstream of the tallest Andes, suggesting that upstream blocking dominates there. |
| Impact of the global warming hiatus on Andean temperature | Journal of Geophysical Research: Atmospheres | Vuille, M.; Franquist, E.; Garreaud, R.; Sven, W.; Casimiro, L.; Cáceres, B. | 2015 | Dinámica del Clima | 10.1002/2015JD023126 | http://onlinelibrary.wiley.com/doi/10.1002/2015JD023126/abstract? | 3745–3757 | Vol: 120 Issue: 9 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | The recent hiatus in global warming is likely to be reflected in Andean temperature, given its close dependence on tropical Pacific sea surface temperature (SST). While recent work in the subtropical Andes has indeed documented a cooling along coastal areas, trends in the tropical Andes show continued warming. Here we analyze spatiotemporal temperature variability along the western side of the Andes with a dense station network updated to 2010 and investigate its linkages to tropical Pacific modes of variability. Results indicate that the warming in tropical latitudes has come to a halt and that the subtropical regions continue to experience cooling. Trends, however, are highly dependent on elevation. While coastal regions experience cooling, higher elevations continue to warm. The coastal cooling is consistent with the observed Pacific Decadal Oscillation (PDO) fingerprint and can be accurately simulated using a simple PDO-analog model. Much of the PDO imprint is modulated and transmitted through adjustments in coastal SST off western South America. At inland and higher-elevation locations, however, temperature trends start to diverge from this PDO-analog model in the late 1980s and have by now emerged above the 1σ model spread. Future warming at higher elevation is likely and will contribute to further vertical stratification of atmospheric temperature trends. In coastal locations, future warming or cooling will depend on the potential future intensification of the South Pacific anticyclone but also on continued temperature dependence on the state of the PDO. ©2015. |
| The southern South American Proteaceae, Embothrium coccineum exhibits intraspecific variation in growth and cluster-root formation depending on climatic and edaphic origins | Plant and Soil | Zúñiga-Feest, A.; Delgado, M.; Bustos-Salazar, A.; Ochoa, V. | 2015 | Cambio de Uso de Suelo | 10.1007/s11104-015-2574-6 | http://link.springer.com/10.1007/s11104-015-2574-6 | 201-213 | Vol: 396 Issue: 1-2 | 0032-079X, 1573-5036 | Thomson Reuters ISI (SCIE) | English | Background and aims Cluster root (CR) functioning has been studied mainly in Proteaceae species from (P)-deficient old soils. However, in southern South America, six species occur in young P rich soils. The aims were: i) to study the growth and CR formation of Embothrium coccineum seedlings from populations contrasting in edaphic and climatic conditions and, ii) to study the effect of P availability on CR formation. Methods Seedlings were grown from seeds collected from nine Chilean populations of E. coccineum (36° to 45° S). After 9 months in a nursery, CR formation and growth were determined. Additionally, seedlings from the two populations at the extreme ends of the distribution were maintained on sand and watered with nutrient solutions including or excluding P. Results All seedlings showed CR formation at 4 months old; however, CR allocation differed in that it was lower in plants from the north versus from the south. CR in seedlings from Curacautín (38°) were suppressed when P supply increased, though this was not seen in seedlings from Coyhaique (45°). Conclusions Results suggest local root adaptation related to both climatic and edaphic conditions. We hypothesize that these features could favor Proteaceae persistence in southern South American ecosystems. |
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| Monitoring global drought using the self-calibrating Palmer Drought Severity Index | State of the Climate 2014, Bulletin of the American Meteorological Society | van der Schrier, G.; Barichivich, J.; Harris, I.; Jones, P.; Osborn, T. | 2015 | Servicios Ecosistémicos | 10.1175/2015BAMSStateoftheClimate.1 | https://journals.ametsoc.org/view/journals/bams/96/7/2015bamsstateoftheclimate.1.xml | S30-S31 | Vol: 96 Issue: 7 | 0003-0007 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | Chapter 2. GLOBAL CLIMATE, Sidebar 2.2 Monitoring global drought using the self-calibrating Palmer drought severity index. |
| Relationships between climate variability and radial growth of Nothofagus pumilio near altitudinal treeline in the Andes of northern Patagonia, Chile | Forest Ecology and Management | Álvarez, C.; Veblen, T.; Christie, D.; González-Reyes, Á. | 2015 | Dinámica del Clima | 10.1016/j.foreco.2015.01.018 | http://www.sciencedirect.com/science/article/pii/S0378112715000201 | 112–121 | Vol: 342 | 0378-1127 | Thomson Reuters ISI (SCIE) | English | Global warming is expected to enhance radial tree growth at alpine treeline sites worldwide. We developed a well-replicated tree-ring chronology from Nothofagus pumilio near treeline in a high precipitation climate on Choshuenco Volcano (40°S) in Chile to examine: (a) variation in tree radial growth in relation to interannual climatic variability; and (b) relationships of radial growth to variability in El Niño Southern Oscillation (ENSO) and the Antarctic Oscillation (AAO) at interannual and decadal time scales. A tree-ring chronology based on 99 tree-ring series from 80 N. pumilio trees near treeline showed a high series intercorrelation (0.48) indicating a strong common environmental signal. Radial growth is negatively correlated with precipitation in late spring (November–December). Temperature and tree growth are positively correlated during late spring and early summer (November–January). Interannual variability in both seasonal climate and in tree growth is strongly teleconnected to ENSO and AAO variability. Radial growth of N. pumilio in this humid high-elevation forest does not show a positive trend over the past half century as predicted from global treeline theory and broadscale warming in the Patagonian-Andean region. Instead, tree growth increased sharply from the 1960s to a peak in the early 1980s but subsequently declined for c. 30years to its lowest level in >100years. The shift to higher radial growth after c. 1976 coincides with a shift towards warmer sea surface temperatures in the tropical Pacific which in turn are associated with warmer growing season temperatures. The decline in tree growth since the mid-1990s is coincident with the increasingly positive phase of the AAO and high spring precipitation periods associated with El Niño conditions. The recent shift towards reduced growth of N. pumilio at this humid high-elevation site coincident with rising AAO mirrors the reduced tree growth beginning in the 1960s for trees growing in relatively xeric, lower elevation sites throughout the Patagonian-Andean region. The current study indicates that N. pumilio growth response in humid high-elevation environments to recent broad-scale warming has been non-linear, and that AAO and ENSO are key climatic forcings of tree growth variability. | |
| Surface ocean response to synoptic-scale variability in wind stress and heat fluxes off south-central Chile | Dynamics of Atmospheres and Oceans | Aguirre, C.; Garreaud, R.; Rutllant, J. | 2014 | Dinámica del Clima | 10.1016/j.dynatmoce.2013.11.001 | http://linkinghub.elsevier.com/retrieve/pii/S0377026513000699 | 64-85 | Vol: 65 | 0377-0265 | Thomson Reuters ISI (SCIE) | All Open Access; Hybrid Gold Open Access | English | The effect of the high frequency (synoptic) variability of wind and heat fluxes upon the surface ocean off south-central Chile (west coast of South America) is investigated using a regional ocean model. We focus our analysis in austral summer, when the regional wind experiences significant day-to-day variability superimposed on a mean, upwelling favorable flow. To evaluate the nature and magnitude of these effects, we performed three identical simulations except for the surface forcing: the climatological run, with long-term monthly mean wind-stresses and heat fluxes; the wind-synoptic run, with daily wind stresses and climatological heat fluxes; and the full-synoptic run, with daily wind-stresses and daily fluxes. The mean currents and surface geostrophic EKE fields show no major differences between simulations, and agree well with those observed in this ocean area. Nevertheless, substantially more ageostrophic EKE is found in the simulations which include synoptic variability of wind-stresses, impacting the total surface EKE and diffusivities, particularly south of Punta Lavapie (37° S), where the lack of major currents implies low levels of geostrophic EKE. Summer mean SSTs are similar in all simulations and agree with observations, but SST variability along the coast is larger in the runs including wind-stress synoptic variability, suggesting a rather linear response of the ocean to cycles of southerly wind strengthening and relaxation. We found that coastal SST variability does not change significantly in the first tenths of kilometers from the shore when including daily heat fluxes, highlighting the prominent role of wind-driven upwelling cycles. In contrast, in the offshore region situated beyond the 50 km coastal strip, it is necessary to include synoptic variability in the heat fluxes to account for a realistic SST variability. |
| Framing disaster resilience: The implications of the diverse conceptualisations of “bouncing back” | Disaster Prevention and Management | Aldunce, P.; Beilin, R.; Handmer, J.; Howden, M. | 2014 | Dimensión Humana | 10.1108/DPM-07-2013-0130 | http://www.emeraldinsight.com/doi/full/10.1108/DPM-07-2013-0130 | 252–270 | Vol: 23 Issue: 3 | 0965-3562 | Thomson Reuters ISI (SSCI) | English | Purpose: To confront the increasingly devastating impacts of disasters and the challenges that climate change is posing to disaster risk management (DRM) there is an imperative to further develop DRM. The resilience approach is emerging as one way to do this, and in the last decade has been strongly introduced into the policy arena, although it is not new for DRM practitioners and researchers. Nevertheless, resilience is a highly contested issue, and there is no agreed definition of it, which has resulted in confusion for stakeholders when applying it to practice. Therefore, the purpose of this paper is to investigate how resilience is framed by researchers and DRM practitioners. Design/methodology/approach: The analytical framework used was Hajer's "social-interactive discourse theory", combined with analysis of government documents, in-depth interviews with practitioners and observation of field and practices within the context of the Natural Disaster Resilience Program in Queensland, Australia. Findings: One of the key findings is that the idea of "bouncing back" is central to the resilience discourse but different interpretations of this idea results in real-world implications. Three different ways (storylines) in which practitioners construct the meaning of disaster resilience emerge from this study. Importantly the divergences between these storylines reveal possibilities for reframing to occur and these could lead to different policy options and practices. Originality/value: The results presented in this paper offer empirical evidence on how resilience is understood on the ground, contributing to extending resilience theory and informing DRM and resilience practice. © Emerald Group Publishing Limited. | |
| Satellite Retrievals of Aerosol Optical Depth over a Subtropical Urban Area: The Role of Stratification and Surface Reflectance | Aerosol and Air Quality Research | Escribano, J.; Gallardo, L.; Rondanelli, R.; Choi, Y. | 2014 | Biogeoquímica; Modelación y Sistemas de Observación | 10.4209/aaqr.2013.03.0082 | https://aaqr.org/articles/aaqr-13-03-oa-0082 | 596-607 | Vol: 14 Issue: 3 | 1680-8584 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | We explore the relationship between satellite retrievals of aerosol optical depth (AOD) and surface aerosol mass concentrations over a subtropical urban area, namely, Santiago, Chile (33.5°S, 70.6°W, 500 m.a.s.l.). We compare 11 years of AOD from the MODerate resolution Imaging Spectroradiometer (MODIS) with in situ particulate matter mass concentrations (PM). MODIS AOD reaches its maximum in summer and minimum in winter, the opposite of the annual cycle of surface PM. To improve our understanding of the relevant governing processes, we use a simple model that estimates the boundary layer (BL) AOD based on measured PM, relative humidity and BL height (BLH) as well as best estimates of aerosol composition, size distribution, and optical properties. Model results indicate that a weak annual AOD cycle is due to the opposite annual cycles in BLH and PM, which is largely supported by the Aerosol Robotic NETwork (AERONET) data collected in 2001 and 2002 in Santiago. We identify a possible bias linked to the operational estimate of surface reflectance that may lead to a spurious summer maximum in MODIS AOD over Santiago. This misfit in surface reflectance appears to affect not only Santiago but also a significant area of the semi-arid Southern South America. Sensitivity experiments with the simple model indicate an underestimate of simulated AOD as compared to AERONET data. This underestimate points to the possible role of residual aerosol layers in the AOD measured at the surface (not included in the simple model). Cirrus clouds appear not to play a significant role in explaining the MODIS AOD seasonality. The need for improved characterizations of aerosol properties and their temporal and spatial distribution in cities such as Santiago is emphasized. |
| OpenFOAM applied to the CFD simulation of turbulent buoyant atmospheric flows and pollutant dispersion inside large open pit mines under intense insolation | Computers & Fluids | Flores, F.; Garreaud, R.; Muñoz, R. | 2014 | Dinámica del Clima | 10.1016/j.compfluid.2013.11.012 | http://www.sciencedirect.com/science/article/pii/S0045793013004507 | 72–87 | Vol: 90 | 0045-7930 | Thomson Reuters ISI (SCIE) | English | The particular conditions of air circulation inside large open pit mines under intense insolation, dominated by mechanical and buoyant effects, are crucial when studying the dispersion of pollutants inside and outside the pit. Considering this, we study this problem using CFD tools able to include the complex geometry characterizing it and the different processes affecting circulation: flow interaction with obstacles, buoyancy, stratification and turbulence. We performed simulations using a previously developed OpenFOAM solver, focusing in the particular case of Chuquicamata, a large open pit mine (∼1. km deep) located in northern Chile. Both idealized and real topographies were used. Given the importance of turbulence in this type of large-scale flows we have used LES to incorporate it in the calculation, using a DES approach to solve the flow near walls.The results from the idealized cases support the idea that buoyant currents foster the exit of particles from the pit and increase the turbulence inside its atmosphere, modifying the purely mechanical recirculatory flow inside the cavity. Differences in the air circulation and dispersion of particles between idealized and non-idealized cases are reported. In particular, there are changes in the intensity and location of the recirculation inside the pit due to variations in the aspect ratio (length/depth) of the cavity along the axis perpendicular to the main flow. Also, the topography surrounding the mine affects the main flow that sweeps the cavity, channeling it along the main axis of the pit and forcing it to enter the cavity through the lower level of the top edge. As a consequence, the patterns of pollutant transport observed in the idealized cases, dominated by near-wall upward currents, are different than those observed in the cases with complex topography, where the dispersion is dominated by internal buoyant upward currents. Anyhow, whether by internal or near wall upward currents, in all buoyant cases considered a large percentage of the particles injected inside the pit leaves the cavity.Further experiments studying the effect of 3D aspect ratio over the mechanically forced internal flow are needed to fully understand the effect of the internal geometry of the pit over the flow. © 2013 Elsevier Ltd. | |
| Temporal dynamics of nitrogen loss in the coastal upwelling ecosystem off central Chile: Evidence of autotrophic denitrification through sulfide oxidation | Limnology and Oceanography | Galán, A.; Faúndez, J.; Thamdrup, B.; Santibáñez, J.; Farías, L. | 2014 | Biogeoquímica | 10.4319/lo.2014.59.6.1865 | http://onlinelibrary.wiley.com/doi/10.4319/lo.2014.59.6.1865/abstract | 1865–1878 | Vol: 59 Issue: 6 | 0024-3590 | Thomson Reuters ISI (SCIE) | English | Coastal upwelling areas are highly productive marine systems in which the development of oxygen-depleted conditions and the availability of diverse electron donors (e.g., organic matter, NHz 4 ,H2S) favor the processes involved in nitrogen (N) loss. We characterize the temporal and vertical variability of anammox and denitrification over the continental shelf off central Chile (36.5°S), through 15N and 13C tracer experiments, including amendments with H2S and S2O2- 3 along with measurements of 15N2 and 15N2O production and oceanographic variables during a year (2009 to 2010). Restricted to the bottom waters, both anammox and denitrification contributed similarly (∼ 500 nmol N2 L-1 d-1) to N loss during spring, while a marked decrease in the activity of these processes occurred in summer (103 and 14 nmolN2 L-1 d-1 for anammox and denitrification, respectively). During fall, denitrification was the only contributor to the observed nitrogen deficit (894 nmol N2 L-1 d-1). Interestingly, a substantial increase in the rates of denitrification (∼ 1200 nmol N2 L-1 d-1) and dark 13C assimilation were observed after the addition of H2S, indicating an autotrophic contribution to denitrification, which could be fueled in situ by H2S emitted from sediments or produced in the water column. The observed patterns seem to be controlled (stimulated or inhibited) by the availability of oxygen, organic matter, andH2S. This study establishes the magnitude and co-occurrence of the different processes responsible for N removal in the coastal upwelling system of central Chile. This linkage of the nitrogen, carbon, and sulfur cycles is relevant to a global climate change scenario. | |
| Lightning in Western Patagonia | Journal of Geophysical Research: Atmospheres | Garreaud, R.; Gabriela Nicora, M.; Bürgesser, R.; Ávila, E. | 2014 | Dinámica del Clima | 10.1002/2013JD021160 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84900524944&partnerID=tZOtx3y1 | 4471–4485 | Vol: 119 Issue: 8 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | On the basis of 8-years (2005-2012) of stroke data from the World Wide Lightning Location Network we describe the spatial distribution and temporal variability of lightning activity over Western Patagonia. This region extends from ∼40°S to 55°S along the west coast of South America, is limited to the east by the austral Andes, and features a hyper-humid, maritime climate. Stroke density exhibits a sharp maximum along the coast of southern Chile. Although precipitation there is largely produced by cold nimbostratus, days with more than one stroke occur up to a third of the time somewhere along the coastal strip. Disperse strokes are also observed off southern Chile. In contrast, strokes are virtually nonexistent over the austral Andes - where precipitation is maximum - and farther east over the dry lowlands of Argentina. Atmospheric reanalysis and satellite imagery are used to characterize the synoptic environment of lightning-producing storms, exemplified by a case study and generalized by a compositing analysis. Lightning activity tends to occur when Western Patagonia is immersed in a pool of cold air behind a front that has reached the coast at ∼40°S. Under these circumstances, midlevel cooling occurs before and is more prominent than near-surface cooling, leading to a weakly unstable postfrontal condition. Forced uplift of the strong westerlies impinging on the coastal mountains can trigger convection and produces significant lightning activity in this zone. Farther offshore, large-scale ascent near the cyclone's center may lift near-surface air parcels, fostering shallow convection and dispersing lightning activity. Key Points Significant lightning activity occurs in Western Patagonia Lightning storms develop under a cold, weakly unstable postfrontal condition Topography and ocean conditions favor lightning activity in Western Patagonia. © 2014. American Geophysical Union. All Rights Reserved. |
| Análisis de los fenómenos meteorológicos y climáticos que afectan la cuenca del río Maipo | Aquae Papers | Garreaud, R.; Viale, M. | 2014 | Dinámica del Clima | http://www.fundacionaquae.org/aquaeteca/aquae-papers/aquae-papers-5/ | 17-29 | Vol: 5 | 2340-3675 | Not indexed | Realizado bajo la coordinación de Manuel Cermerón, en el estudio han participado profesores e investigadores de la Universidad de Chile y de la Universidad Federico Santa María. El estudio considera tres ámbitos de investigación: análisis de los fenómenos Meteorológicos y Climáticos que afectan la Cuenca del Maipo, análisis de las características Geológicas y Geotécnicas de laderas en la Cuenca del Maipo, y un estudio sobre la determinación de posibles impactos en la gestión de los abastecimientos humanos de agua de la zona metropolitana de Chile y una proposición de alternativas de solución que mitiguen dichos impactos. | |||
| Forcings and feedbacks in the GeoMIP ensemble for a reduction in solar irradiance and increase in CO 2 | Journal of Geophysical Research: Atmospheres | Huneeus, N.; Boucher, O.; Alterskjaer, K.; Cole, J.; Curry, C.; Ji, D.; Jones, A.; Kravitz, B.; Kristjánsson, J.; Moore, J.; Muri, H.; Niemeier, U.; Rasch, P.; Robock, A.; Singh, B.; Schmidt, H.; Schulz, M.; Tilmes, S.; Watanabe, S.; Yoon, J. | 2014 | Modelación y Sistemas de Observación | 10.1002/2013JD021110 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84901723947&partnerID=tZOtx3y1 | 5226–5239 | Vol: 119 Issue: 9 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | The effective radiative forcings (including rapid adjustments) and feedbacks associated with an instantaneous quadrupling of the preindustrial CO |
| Ecosystem services in changing landscapes: An introduction | Landscape Ecology | Iverson, L.; Echeverría, C.; Nahuelhual, L.; Luque, S. | 2014 | Dimensión Humana | 10.1007/s10980-014-9993-2 | http://link.springer.com/article/10.1007%2Fs10980-014-9993-2 | 181–186 | Vol: 29 Issue: 2 | 0921-2973 | Thomson Reuters ISI (SCIE) | English | The concept of ecosystem services from landscapes is rapidly gaining momentum as a language to communicate values and benefits to scientists and lay alike. Landscape ecology has an enormous contribution to make to this field, and one could argue, uniquely so. Tools developed or adapted for landscape ecology are being increasingly used to assist with the quantification, modelling, mapping, and valuing of ecosystem services. Several of these tools and methods encased therein are described among the eleven papers presented in this special issue, and their application has the potential to facilitate the management and promotion of services within ecosystems. Papers are associated with each of the four key categories of services that ecosystems provide to humans: supporting, provisioning, regulating, and cultural. The papers represent work conducted in eleven different countries, especially from South America. Each carries a unique approach to address a particular question pertaining to a particular set of ecosystem services. These studies are designed to inform and improve the economic, environmental and social values of the ecosystem services. This knowledge should help to develop new management alternatives for sustaining and planning ecosystems and the services they provide at different scales in space and time. We believe that these papers will create interest and inform management of some potential methods to evaluate ecosystem services at the landscape level with an integrative approach, offering new tools for management and conservation. © 2014 Springer Science+Business Media Dordrecht (outside the USA). | |
| Climatic and disturbance influences on the temperate rainforests of northwestern Patagonia (40 °S) since ∼14,500 cal yr BP | Quaternary Science Reviews | Jara, I.; Moreno, P. | 2014 | Dinámica del Clima | 10.1016/j.quascirev.2014.01.024 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84897080261&partnerID=tZOtx3y1 | 217–228 | Vol: 90 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | We present a detailed record from Lago Pichilafquén to unravel the vegetation, climate and disturbance history of the lowlands of northwestern Patagonia (40°S) since 14,500calyrBP. The presence of 30 tephras throughout the record attest for the proximity of the site to active volcanic centres and allows assessment of the role of volcanic disturbance on past vegetation and fire regime shifts. We interpretalternations in dominance between North Patagonian and Valdivian rainforests driven by changes in temperature and precipitation of westerly origin at multi-millennial and millennial timescales. These trends were punctuated by centennial-scale changes, most of which were coeval with or immediately followed the deposition of tephras and/or paleofires. We identify departures of the local vegetation from the regional trend between 2400 and 7100calyrBP, which we interpret as a response of rainforest vegetation and local fire regimes to the disturbance effect of tephra deposition near Lago Pichilafquén. We also find that volcanic disturbance promoted consistent increases in Eucryphia/Caldcluvia within 30 years and paleofires between 60 and 120years following tephra deposition. Comparisons with palynological records having similar span, time resolution and age control suggest that regional climate has played a central role on the establishment, composition and maintenance of temperate rainforests. This influence is overprinted by disturbance regimes at the local and landscape level, driving divergences and heterogeneity especially at times of relatively weak climatic forcing. © 2014 Elsevier Ltd. | |
| An episode of extremely low precipitable water vapour over Paranal observatory | Monthly Notices of the Royal Astronomical Society | Kerber, F.; Querel, R.; Rondanelli, R.; Hanuschik, R.; van den Ancker, M.; Cuevas, O.; Smette, A.; Smoker, J.; Rose, T.; Czekala, H. | 2014 | Biogeoquímica | 10.1093/mnras/stt2404 | http://mnras.oxfordjournals.org/content/439/1/247 | 247–255 | Vol: 439 Issue: 1 | 0035-8711 | Thomson Reuters ISI (SCIE) | English | We report on an episode of extremely low precipitable water vapour (PWV) of approximately 0.1mm with a duration of more than 12 h at European Southern Observatory's Paranal observatory [2635m above sea level (asl)]. Such conditions are more commonly expected at sites at much higher altitude such as ALMA on the Chajnantor plateau (5000m asl) or otherwise particularly dry sites such as locations in Antarctica. We provide a full account ofthe measurements of PWV and other relevant atmospheric parameters. An explanation of the observed conditions is given in terms of the prevailing meteorological pattern. Based on statistical evidence from measurements by VLT spectrographs (UVES and CRIRES) covering more than a decade, we find that PWV <0.2mm can be expected on less than 1 per cent of the nights, while <0.5mm is encountered on 6-7 nights per year (≈2 per cent). The scientificpotential of using this small but significant fraction of observing time is illustrated in the context of service modeSociety. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. | |
| Increased dust deposition in the Pacific Southern Ocean during glacial periods. | Science | Lamy, F.; Gersonde, R.; Winckler, G.; Esper, O.; Jaeschke, A.; Kuhn, G.; Ullermann, J.; Martinez-Garcia, A.; Lambert, F.; Kilian, R. | 2014 | Modelación y Sistemas de Observación | 10.1126/science.1245424 | http://science.sciencemag.org/content/343/6169/403 | 403–407 | Vol: 343 Issue: 6169 | 0036-8075 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Dust deposition in the Southern Ocean constitutes a critical modulator of past global climate variability, but how it has varied temporally and geographically is underdetermined. Here, we present data sets of glacial-interglacial dust-supply cycles from the largest Southern Ocean sector, the polar South Pacific, indicating three times higher dust deposition during glacial periods than during interglacials for the past million years. Although the most likely dust source for the South Pacific is Australia and New Zealand, the glacial-interglacial pattern and timing of lithogenic sediment deposition is similar to dust records from Antarctica and the South Atlantic dominated by Patagonian sources. These similarities imply large-scale common climate forcings, such as latitudinal shifts of the southern westerlies and regionally enhanced glaciogenic dust mobilization in New Zealand and Patagonia. |
| Le principe des responsabilités communes mais différenciées dans le régime international du climat | Les Cahiers de droit | Maljean-Dubois, S. | 2014 | Dimensión Humana | 10.7202/1025500ar | http://www.erudit.org/fr/revues/cd1/2014-v55-n1-cd01443/1025500ar/ | 83-112 | Vol: 55 Issue: 1 | 1918-8218 | Lexis Nexis; LegalTrac | In the area of international environmental agreements, the field of climate change provides the best illustration of the application of the principle of common but differentiated responsibilities. However, it also reveals the difficulties raised by its application. Justice, equity and common but differentiated responsibilities can be claimed by all Parties, sometimes with diametrically-opposed goals. Since the adoption of the Framework Convention (1992) and the Kyoto Protocol (1997), the structure of global carbon emissions has changed considerably, in particular as a result of increased emissions from China. The principle, used as a shield by some and as a foil by others, is currently referred to frequently in difficult « post-2012 » and « post 2020 » negotiations, and its role is gradually changing. | ||
| Concepts and methods for landscape multifunctionality and a unifying framework based on ecosystem services | Landscape Ecology | Mastrangelo, M.; Weyland, F.; Villarino, S.; Barral, M.; Nahuelhual, L.; Laterra, P. | 2014 | Dimensión Humana | 10.1007/s10980-013-9959-9 | http://link.springer.com/10.1007/s10980-013-9959-9 | 345-358 | Vol: 29 Issue: 2 | 0921-2973 | Thomson Reuters ISI (SCIE) | English | The potential of landscapes to supply multiple benefits to society beyond commodities production has received increasing research and policy attention. Linking the concept of multifunctionality with the ecosystem services (ES) approach offers a promising avenue for producing scientific evidence to inform landscape planning, e.g., about the relative utility of land-sharing and land-sparing. However, the value for decision-making of ES-based multifunctionality assessments has been constrained by a significant conceptual and methodological dispersion. To contribute towards a cohesive framework for landscape multifunctionality, we analyse case studies of joint ES supply regarding ten criteria designed to ultimately answer four aspects: (i) the multifunctionality of what (e.g., landscapes), (ii) the type of multifunctionality (e.g., based on ES synergies), (iii) the procedure of multifunctionality assessments, and (iv) the purpose of multifunctionality. We constructed a typology of methodological approaches based on scores for criteria describing the evaluation method and the level of stakeholder participation in assessments of joint ES supply. Surveyed studies and underlying types of methodological approaches (spatial, socio-spatial, functional, spatio-functional) differed in most criteria. We illustrate the influence of methodological divergence on planning recommendations by comparing two studies employing contrasting approaches (spatial and functional) to assess the joint supply of wildlife habitat and agricultural production in the Argentine Chaco. We distinguish between a pattern-based and process-based multifunctionality, where the latter can only be detected through approaches considering the ecological processes (e.g., ES complementarities) supporting the supply of multiple ES (functional and spatio-functional). Finally, we propose an integrated approach for assessing a socially-relevant process-based multifunctionality. | |
| Ocean–Cloud–Atmosphere–Land Interactions in the Southeastern Pacific: The VOCALS Program | Bulletin of the American Meteorological Society | Mechoso, C.; Wood, R.; Weller, R.; Bretherton, C.; Clarke, A.; Coe, H.; Fairall, C.; Farrar, J.; Feingold, G.; Garreaud, R.; Grados, C.; McWilliams, J.; de Szoeke, S.; Yuter, S.; Zuidema, P. | 2014 | Dinámica del Clima | 10.1175/BAMS-D-11-00246.1 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84900314869&partnerID=tZOtx3y1 | 357–375 | Vol: 95 Issue: 3 | 0003-0007 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | The Variability of American Monsoon Systems (VAMOS) Ocean-Cloud-Atmosphere- Land Study (VOCALS) is an international research program focused upon improved understanding and modeling of the southeast Pacific (SEP) climate system on diurnal to inter annual time scales. The SEP is characterized by strong coastal ocean upwelling, the coldest sea surface temperatures (SST) at comparable latitudes, the planet's most extensive subtropical stratocumulus deck, and a high and steep cordillera to the east. The VOCALS program is built on several research activities in SEP climate research (Mechoso and Wood 2010). The preceding Eastern Pacific Investigation of Climate Processes in the Coupled Ocean-Atmosphere System (EPIC) provided important insight on the intertropical convergence zone (ITCZ)/cold-tongue complex and marine boundary layer (MBL) clouds over the SEP. |
| North Atlantic forcing of tropical Indian Ocean climate. | Nature | Mohtadi, M.; Prange, M.; Oppo, D.; De Pol-Holz, R.; Merkel, U.; Zhang, X.; Steinke, S.; Lückge, A. | 2014 | Biogeoquímica | 10.1038/nature13196 | http://www.nature.com/doifinder/10.1038/nature13196 http://www.ncbi.nlm.nih.gov/pubmed/24784218 | 76–80 | Vol: 509 Issue: 7498 | 0028-0836 | Thomson Reuters ISI (SCIE) | English | The response of the tropical climate in the Indian Ocean realm to abrupt climate change events in the North Atlantic Ocean is contentious. Repositioning of the intertropical convergence zone is thought to have been responsible for changes in tropical hydroclimate during North Atlantic cold spells, but the dearth of high-resolution records outside the monsoon realm in the Indian Ocean precludes a full understanding of this remote relationship and its underlying mechanisms. Here we show that slowdowns of the Atlantic meridional overturning circulation during Heinrich stadials and the Younger Dryas stadial affected the tropical Indian Ocean hydroclimate through changes to the Hadley circulation including a southward shift in the rising branch (the intertropical convergence zone) and an overall weakening over the southern Indian Ocean. Our results are based on new, high-resolution sea surface temperature and seawater oxygen isotope records of well-dated sedimentary archives from the tropical eastern Indian Ocean for the past 45,000 years, combined with climate model simulations of Atlantic circulation slowdown under Marine Isotope Stages 2 and 3 boundary conditions. Similar conditions in the east and west of the basin rule out a zonal dipole structure as the dominant forcing of the tropical Indian Ocean hydroclimate of millennial-scale events. Results from our simulations and proxy data suggest dry conditions in the northern Indian Ocean realm and wet and warm conditions in the southern realm during North Atlantic cold spells. | |
| Southern Annular Mode-like changes in southwestern Patagonia at centennial timescales over the last three millennia. | Nature Communications | Moreno, P.; Vilanova, I.; Villa-Martínez, R.; Garreaud, R.; Rojas, M.; De Pol-Holz, R. | 2014 | Dinámica del Clima; Modelación y Sistemas de Observación; Servicios Ecosistémicos | 10.1038/ncomms5375 | http://www.nature.com/ncomms/2014/140710/ncomms5375/full/ncomms5375.html | art4375 | Vol: 5 | 2041-1723 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Late twentieth-century instrumental records reveal a persistent southward shift of the Southern Westerly Winds during austral summer and autumn associated with a positive trend of the Southern Annular Mode (SAM) and contemporaneous with glacial recession, steady increases in atmospheric temperatures and CO2 concentrations at a global scale. However, despite the clear importance of the SAM in the modern/future climate, very little is known regarding its behaviour during pre-Industrial times. Here we present a stratigraphic record from Lago Cipreses (51°S), southwestern Patagonia, that reveals recurrent ∼200-year long dry/warm phases over the last three millennia, which we interpret as positive SAM-like states. These correspond in timing with the Industrial revolution, the Mediaeval Climate Anomaly, the Roman and Late Bronze Age Warm Periods and alternate with cold/wet multi-centennial phases in European palaeoclimate records. We conclude that SAM-like changes at centennial timescales in southwestern Patagonia represent in-phase interhemispheric coupling of palaeoclimate over the last 3,000 years through atmospheric teleconnections. |
| Patterns and drivers of Araucaria araucana forest growth along a biophysical gradient in the northern Patagonian Andes: Linking tree rings with satellite observations of soil moisture: Patterns and drivers of Araucaria growth | Austral Ecology | Muñoz, A.; Barichivich, J.; Christie, D.; Dorigo, W.; Sauchyn, D.; González-Reyes, Á.; Villalba, R.; Lara, A.; Riquelme, N.; González, M. | 2014 | Dinámica del Clima; Servicios Ecosistémicos | 10.1111/aec.12054 | http://doi.wiley.com/10.1111/aec.12054 | 158-169 | Vol: 39 Issue: 2 | 1442-9985 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Araucaria araucana (Araucaria) is a long-lived conifer growing along a sharp west–east biophysical gradient in the Patagonian Andes. The patterns and climate drivers of Araucaria growth have typically been documented on the driest part of the gradient relying on correlations with meteorological records, but the lack of in situ soil moisture observations has precluded an assessment of the growth responses to soil moisture variability. Here, we use a network of 21 tree-ring width chronologies to investigate the spatiotemporal patterns of tree growth through the entire gradient and evaluate their linkages with regional climate and satellite-observed surface soil moisture variability. We found that temporal variations in tree growth are remarkably similar throughout the gradient and largely driven by soil moisture variability. The regional spatiotemporal pattern of tree growth was positively correlated with precipitation (r = 0.35 for January 1920–1974; P < 0.01) and predominantly negatively correlated with temperature (r = −0.38 for January–March 1920–1974; P < 0.01) during the previous growing season. These correlations suggest a temporally lagged growth response to summer moisture that could be associated with known physiological carry-over processes in conifers and to a response to moisture variability at deeper layers of the rooting zone. Notably, satellite observations revealed a previously unobserved response of Araucaria growth to summer surface soil moisture during the current rather than the previous growing season (r = 0.65 for 1979–2000; P < 0.05). This new response has a large spatial footprint across the mid-latitudes of the South American continent (35°–45°S) and highlights the potential of Araucaria tree rings for palaeoclimatic applications. The strong moisture constraint on tree growth revealed by satellite observations suggests that projected summer drying during the coming decades may result in regional growth declines in Araucaria forests and other water-limited ecosystems in the Patagonian Andes. |
| Land use change and ecosystem services provision: a case study of recreation and ecotourism opportunities in southern Chile | Landscape Ecology | Nahuelhual, L.; Carmona, A.; Aguayo, M.; Echeverria, C. | 2014 | Dimensión Humana | 10.1007/s10980-013-9958-x | http://link.springer.com/10.1007/s10980-013-9958-x | 329-344 | Vol: 29 Issue: 2 | 0921-2973 | Thomson Reuters ISI (SCIE) | English | Land use and cover change (LUCC) is among the most important factors affecting ecosystem services. This study examines the influence of LUCC on recreation and ecotourism opportunities over three decades in southern Chile. An in-depth analysis of the transition matrix was conducted based on Landsat images from 1976, 1985, 1999 and 2007. Main LUCC trajectories were linked to two ecosystem service indicators: (i) Recreation and ecotourism potential, measured in a 0–100 point scale; and (ii) Recreation and ecotourism opportunities, measured in visitors/ha. A total of 900 trajectories occurred in the landscape between 1976 and 2007. The most important trajectories in terms of area, were the recent degradation of old-growth to secondary forest between 1999 and 2007 (23,290 ha; 13.5 % of landscape), and the early clearing of shrublands for agriculture and pasture land between 1976 and 1985 (7,187 ha, 4.2 % of landscape). In turn, the single most influential trajectory on the magnitude of the indicators was early and permanent degradation of old-growth forest to secondary forest. As a result of these landscape changes, recreation and ecotourism opportunities for the entire landscape were reduced from 65,050 persons in 1976 to 25,038 persons in 1985, further declining to 22,346 and 21,608 persons in 1999 and 2007, respectively. This decrease resulted from changes in specific attributes (i.e. emblematic flora and fauna and forest structure) that were affected by forest degradation and fragmentation. These results highlight the substantial impact of LUCC on recreation opportunity decline, which mirrors biodiversity losses in the study area. | |
| A mapping approach to assess intangible cultural ecosystem services: The case of agriculture heritage in Southern Chile | Ecological Indicators | Nahuelhual, L.; Carmona, A.; Laterra, P.; Barrena, J.; Aguayo, M. | 2014 | Dimensión Humana | 10.1016/j.ecolind.2014.01.005 | http://www.sciencedirect.com/science/article/pii/S1470160X14000077 | 90–101 | Vol: 40 | 1470-160X | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Modeling and mapping of cultural ecosystem services (CES) represents a significant gap in ecosystem service research. A GIS-based methodological framework was developed and applied to map agricultural heritage (AH), understood as a non-divisible combination of three cultural services (dimensions, D): the heritage value associated to a culturally significant species (i.e. Chiloé native potato) (D1); the traditional systems of knowledge of AH keepers (D2); and the social relations among them (D3). The final aim of the study was to provide indicators of the "final" service (AHi, measured in a 0-100 point scale) and its benefits (AHB, measured in US$/ha), capable to display areas where high value farmland was located. In essence, AHi comprised a set of biocultural variables validated and weighted by expert opinion. The experts gave the maximum importance to 5 variables: number of native potato varieties cultivated (D1), use of own seed (D1), form in which cultivation knowledge was acquired by the keeper (D2), exchange of own seed (D3), and number of other potato keepers known (D3). In turn, AHB reflected society's willingness to pay for the nonmaterial benefits of AH conservation. Since these benefits "propagate" across space extending from local to unknown and distant beneficiaries, and the aim was to identify the most valuable areas for their capacity to satisfy a potential demand, AHB was spatialized following the approach of "ascribing" the potential benefits to their "point of provision". Thus the highest values of AHi coincided with the highest values of AHB (US$10.64-8.64 ha-1) a comprised 5608 ha of the landscape, and similarly the lowest values of AHi matched the lowest values of AHB (US$1.69-0.18 ha-1) comprising 13,070 ha of the landscape. © 2014 Elsevier Ltd. |
| Vegetation, fire and climate change in central-east Isla Grande de Chiloé (43°S) since the Last Glacial Maximum, northwestern Patagonia | Quaternary Science Reviews | Pesce, O.; Moreno, P. | 2014 | Dinámica del Clima | 10.1016/j.quascirev.2014.02.021 | http://www.sciencedirect.com/science/article/pii/S0277379114000705 | 143–157 | Vol: 90 | 0277-3791 | Thomson Reuters ISI (SCIE) | English | We present a detailed record from Lago Lepué to examine vegetation, climate and fire-regime changes since the Last Glacial Maximum (LGM) in central-east Isla Grande de Chiloé (43°S), northwestern Patagonia. Precipitation in this region correlates with the intensity of the southern westerly winds (SWW), allowing reconstruction of past SWW behavior through precipitation-sensitive sensors. Recession from the LGM glacier margins exposed the central-east sector of Isla Grande de Chiloé by 17,800calyrBP, followed by the immediate colonization of pioneer cold-resistant herbs/shrubs and rapid establishment of closed-canopy Nothofagus forests by 17,000calyrBP. Broad-leaved temperate rainforests have persisted since then with compositional changes driven by changes in temperature, hydrologic balance and disturbance regimes. We detect low lake levels and enhanced fire activity between 800-2000, 4000-4300, ∼8000-11,000 and 16,100-17,800calyrBP, implying southward shifts and/or weaker SWW flow that alternated with cold, humid phases with muted fire activity. Covariation in paleoclimate trends revealed by the Lago Lepué record with tropical and Antarctic records since the LGM, suggests that the SWW have been a highly dynamic component of the climate system capable of linking climate changes from low- and high-southern latitudes during the Last Glacial termination and the current interglacial. © 2014 Elsevier Ltd. | |
| A synoptic climatology of the near-surface wind along the west coast of South America | International Journal of Climatology | Rahn, D.; Garreaud, R. | 2014 | Dinámica del Clima | 10.1002/joc.3724 | http://doi.wiley.com/10.1002/joc.3724 | 780-792 | Vol: 34 Issue: 3 | 0899-8418 | Thomson Reuters ISI (SCIE) | English | Prevailing wind along the west coast of South America is equatorward, driven by the southeast Pacific anticyclone. The wind induces strong coastal upwelling that supports one of the most important fisheries in the world. This region lacks a dense network of in situ observations, so the high resolution (0.313°) NCEP Climate Forecast System Reanalysis is used here to present a synoptic climatology of the coastal wind along the Chile/Peru coast. Covariability between the alongshore pressure gradient and alongshore wind, which was previously identified for synoptic time scales near central Chile, is generalized for the whole coast and over annual time scales. Particular attention is paid to three prominent upwelling regions: Pisco (14.8°S), Punta Lengua de Vaca (30.0°S), and Punta Lavapie (36.4°S). Previous work has identified local maxima at these points but these are embedded in a broader low-level jet that exhibits a marked seasonal cycle of strong wind days due to the migration of the anticyclone and is associated with a shift of both the mean wind and a more frequent recurrence of strong wind events. Alongshore wind near Pisco is normally distributed year-round with a seasonal shift in the mean. Larger variability in the mean and distribution is found at Lavapie, associated with the seasonal change in storm tracks. The synoptic evolution that drives high-wind events at each location is characterized. A midlevel trough and surface cyclone precede wind maxima at each location and are followed by strong midlevel ridging and a strengthened surface anticyclone. | |
| Scale, urban risk and adaptation capacity in neighborhoods of Latin American cities | Habitat International | Romero-Lankao, P.; Hughes, S.; Qin, H.; Hardoy, J.; Rosas-Huerta, A.; Borquez, R.; Lampis, A. | 2014 | Dimensión Humana | 10.1016/j.habitatint.2013.12.008 | http://www.sciencedirect.com/science/article/pii/S0197397513001331 http://www.scopus.com/inward/record.url?eid=2-s2.0-84893420542&partnerID=tZOtx3y1 | 224–235 | Vol: 42 | 0197-3975 | Thomson Reuters ISI (SSCI) | English | While urbanites are vulnerable to a suite of risks that climate change might aggravate (e.g., mortality from extreme temperatures and property damages from floods), urban populations and decision makers may also be positioned to most effectively respond to such risks. Research is needed however, exploring both the multilevel factors and processes that determine urban risk and the complex pathways from hazards to impacts, and from perceptions and coping responses to adaptation. This paper analyzes whether and under what circumstances urban populations experience risk in selected Latin American neighborhoods of Bogotá, Buenos Aires, Mexico and Santiago; it assesses their adaptation capacity, i.e., ability to perceive and respond to hazards. It finds that urban risk depends on scale: hazards, adaptation capacities, responses and their underlying societal and physical drivers vary across urban households, neighborhoods and cities. Informality is a state of regulatory flux, where access to land and livelihood options cannot be fixed and mapped according to any prearranged sets of laws and planning mechanisms, that has a profound influence on risk and adaptation capacities across scales. For instance, informality becomes the site of considerable state power where some forms of growth in risk-prone areas enjoy state sanction while others are criminalized. The informal status becomes both a source of stigmatization that disempowers informal neighborhoods and a systemic determinant of lack of access to assets and options for adaptation capacity. | |
| Recuperación natural del bosque siempreverde afectado por tala rasa y quema en la Reserva Costera Valdiviana, Chile | Bosque | Romero-Mieres, M.; González, M.; Lara, A. | 2014 | Servicios Ecosistémicos | 10.4067/S0717-92002014000300001 | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-92002014000300001&lng=en&nrm=iso&tlng=en | 257–267 | Vol: 35 Issue: 3 | 0717-9200 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | Spanish | This study aimed at understanding the natural recovery of the evergreen forest a decade after being affected by clearcutting and burning, in a site located in the Valdivian Coastal Reserve (39°56’ S-73°40’ W). A total of 27 circular (50.2 m2) plots with eight subplots each were established. Floristic composition was recorded and quantitative, diametric and age structures were determined. The results show a richness of 77 vascular species (84.4% natives), with Lophosoria quadripinnata presenting the highest relative cover (20.7%). The presence of hemicryptophytes (35%) indicates human intervention in the place. Trees were the main form of growth, being Drimys winteri, Saxegothaea conspicua and Amomyrtus luma the species with higher plant density. The latter two species growing under Chusquea macrostachya and Lophosoria quadripinnata cover. Drimys winteri and Embothrium coccineum were established immediately after the anthropogenic disturbance of clearcutting and burning, confirming the pioneering character of these two species after highly severe disturbances. Regeneration of Nothofagus nitida was scarce in the area, probably associated with low availability and seed dispersal capacity from surrounding forests. Understanding the early response of evergreen forests affected by anthropogenic disturbance is very important for assisting and guiding the ecological restoration of these forest ecosystems. |
| Formulation, calibration and validation of the DAIS model (version 1), a simple Antarctic ice sheet model sensitive to variations of sea level and ocean subsurface temperature | Geoscientific Model Development | Shaffer, G. | 2014 | Modelación y Sistemas de Observación | 10.5194/gmd-7-1803-2014 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84940312463&partnerID=tZOtx3y1 | 1803–1818 | Vol: 7 Issue: 4 | 1991-9603 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The DCESS (Danish Center for Earth System Science) Antarctic Ice Sheet (DAIS) model is presented. Model hindcasts of Antarctic ice sheet (AIS) sea level equivalent are forced by reconstructed Antarctic temperatures, global mean sea level and high-latitude, ocean subsurface temperatures, the latter calculated using the DCESS model forced by reconstructed global mean atmospheric temperatures. The model is calibrated by comparing such hindcasts for different model configurations with paleoreconstructions of AIS sea level equivalent from the last interglacial, the last glacial maximum and the mid-Holocene. The calibrated model is then validated against present estimates of the rate of AIS ice loss. It is found that a high-order dependency of ice flow at the grounding line on water depth there is needed to capture the observed response of the AIS at ice age terminations. Furthermore, it is found that a dependency of this ice flow on ocean subsurface temperature by way of ice shelf demise and a resulting buttressing decrease is needed to explain the contribution of the AIS to global mean sea level rise at the last interglacial. When forced and calibrated in this way, model hindcasts of the rate of present-day AIS ice loss agree with recent, data-based estimates of this ice loss rate. © Author(s) 2014. |
| Climate and soil attributes determine plant species turnover in global drylands. | Journal of biogeography | Ulrich, W.; Soliveres, S.; Maestre, F.; Gotelli, N.; Quero, J.; Delgado-Baquerizo, M.; Bowker, M.; Eldridge, D.; Ochoa, V.; Gozalo, B.; Valencia, E.; Berdugo, M.; Escolar, C.; García-Gómez, M.; Escudero, A.; Prina, A.; Alfonso, G.; Arredondo, T.; Bran, D.; Cabrera, O.; Cea, A.; Chaieb, M.; Contreras... | 2014 | Servicios Ecosistémicos | 10.1111/jbi.12377 | http://www.scopus.com/inward/record.url?eid=2-s2.0-84939260935&partnerID=tZOtx3y1 | 2307–2319 | Vol: 41 Issue: 12 | 0305-0270 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | AIM: Geographic, climatic, and soil factors are major drivers of plant beta diversity, but their importance for dryland plant communities is poorly known. This study aims to: i) characterize patterns of beta diversity in global drylands, ii) detect common environmental drivers of beta diversity, and iii) test for thresholds in environmental conditions driving potential shifts in plant species composition. LOCATION: 224 sites in diverse dryland plant communities from 22 geographical regions in six continents. METHODS: Beta diversity was quantified with four complementary measures: the percentage of singletons (species occurring at only one site), Whittake's beta diversity (β(W)), a directional beta diversity metric based on the correlation in species occurrences among spatially contiguous sites (β(R(2))), and a multivariate abundance-based metric (β(MV)). We used linear modelling to quantify the relationships between these metrics of beta diversity and geographic, climatic, and soil variables. RESULTS: Soil fertility and variability in temperature and rainfall, and to a lesser extent latitude, were the most important environmental predictors of beta diversity. Metrics related to species identity (percentage of singletons and β(W)) were most sensitive to soil fertility, whereas those metrics related to environmental gradients and abundance ((β(R(2))) and β(MV)) were more associated with climate variability. Interactions among soil variables, climatic factors, and plant cover were not important determinants of beta diversity. Sites receiving less than 178 mm of annual rainfall differed sharply in species composition from more mesic sites (> 200 mm). MAIN CONCLUSIONS: Soil fertility and variability in temperature and rainfall are the most important environmental predictors of variation in plant beta diversity in global drylands. Our results suggest that those sites annually receiving ∼ 178 mm of rainfall will be especially sensitive to future climate changes. These findings may help to define appropriate conservation strategies for mitigating effects of climate change on dryland vegetation. |
| Summer Precipitation Events over the Western Slope of the Subtropical Andes | Monthly Weather Review | Viale, M.; Garreaud, R. | 2014 | Dinámica del Clima | 10.1175/MWR-D-13-00259.1 | http://journals.ametsoc.org/doi/abs/10.1175/MWR-D-13-00259.1 | 1074–1092 | Vol: 142 Issue: 3 | 0027-0644 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Summertime [December-February (DJF)] precipitation over the western slopes of the subtropical Andes (32°-368°) accounts for less than 10% of the annual accumulation, but it mostly occurs as rain and may trigger landslides leading to serious damages. Based on 13 year of reanalysis, in situ observations, and satellite imagery, a synoptic climatology and physical diagnosis reveal two main weather types lead to distinct precipitation systems. The most frequent type (̃80% of the cases) occurs when a short-wave midlevel trough with weak winds and thermally driven mountain winds favor the development of convective precipitation during the daytime. The trough progresses northwest of a long-lasting warm ridge, which produces low-level easterly airflow that enhances its buoyancy as it moves over the arid land of western Argentina toward the Andes. The weak winds aloft facilitate the penetration of the moist easterly flow into the Andes. Midlevel flow coming from the west side of the Andes is decoupled from the low-level maritime air by a temperature inversion, and thus provides little moisture to support precipitation. The less frequent type (̃20% of the cases) occurs when a deep midlevel trough and strong westerly flow produces stratiform precipitation. This type has a baroclinic nature akin to winter storms, except that they are rare in summer and there is no evidence of a frontal passage at low levels. The lifting and cooling ahead of the trough erode the typical temperature inversion over the Pacific coast, and thus allows upslope transport of low-level marine air by the strong westerlies forming a precipitating cloud cap on the western slope of the Andes. © 2014 American Meteorological Society. |
| Continental-scale temperature variability during the past two millennia | Nature Geoscience | Ahmed, M.; Anchukaitis, K.; Asrat, A.; Borgaonkar, H.; Braida, M.; Buckley, B.; Büntgen, U.; Chase, B.; Christie, D.; Cook, E.; Curran, M.; Diaz, H.; Esper, J.; Fan, Z.; Gaire, N.; Ge, Q.; Gergis, J.; González-Rouco, J.; Goosse, H.; Grab, S.; Graham, N.; Graham, R.; Grosjean, M.; Hanhijärvi, S.; Kau... | 2013 | Dinámica del Clima; Servicios Ecosistémicos | 10.1038/NGEO1797 | http://www.nature.com/ngeo/journal/v6/n5/full/ngeo1797.html | 339–346 | Vol: 6 | 1752-0894 | Thomson Reuters ISI (SCIE) | English | Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century. At multi- decadal to centennial scales, temperature variability shows distinctly different regional patterns, with more similarity within each hemisphere than between them. There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between ad 1580 and 1880, punctuated in some regions by warm decades during the eighteenth century. The transition to these colder conditions occurred earlier in the Arctic, Europe and Asia than in North America or the Southern Hemisphere regions. Recent warming reversed the long-term cooling; during the period ad 1971–2000, the area-weighted average reconstructed temperature was higher than any other time in nearly 1,400 years. D | |
| Greenhouse gas emissions from the Tubul-Raqui estuary (central Chile 36°S) | Estuarine, Coastal and Shelf Science | Daniel, I.; DeGrandpre, M.; Farías, L. | 2013 | Biogeoquímica | 10.1016/j.ecss.2013.09.019 | http://www.sciencedirect.com/science/article/pii/S0272771413004265 | 31–44 | Vol: 134 | 0272-7714 | Thomson Reuters ISI (SCIE) | English | The Tubul-Raqui estuary is a coastal system off central Chile at 37°S, adjacent to an active coastal upwelling area, which undergoes rapid changes associated with natural and anthropogenic perturbations. Biogenic greenhouse gas cycling and the gas saturation levels are good indicators of microbial metabolism and trophic status in estuaries. The dissolved greenhouse gases CO2, CH4 and N2O and other biological and chemical variables were spatially recorded in this estuary over two seasons (summer and winter) and over one-half of one tidal cycle. Tidal and spatial variability of these gases indicated they had different origins within the system. Surface waters were always oversaturated in CO2 (up to 578%) and CH4 (up to 6200%) with respect to the atmosphere. But while CO2 seems to come from marine and in situ metabolism, CH4 appears to be more influenced by fluvial and adjacent salt marsh areas. In contrast, N2O was mostly undersaturated and sediments seem to be largely responsible for its consumption. Strong seasonal variability was also observed in CO2 and CH4 fluxes, being tenfold (from-319 to 714mmolm-2d-1) and fivefold (from 0.33 to 2.5mmolm-2d-1) higher, respectively, in the austral summer compared to winter. In contrast, only small seasonal differences in N2O fluxes were found ranging from -59 to 28 μmol m-2 d-1. These temporal patterns can be explained not only in terms of hydrological and nutrient balances within the system, but also by the influence of wind-driven upwelling processes. Additionally, potential effects of changes in nutrient load and freshwater discharge on net ecosystem metabolism (i.e., autotrophy or heterotrophy) and therefore, on the production/removal of greenhouse gases in this system were explored. © 2013 Elsevier Ltd. | |
| Decoupling of soil nutrient cycles as a function of aridity in global drylands | Nature | Delgado-Baquerizo, M.; Maestre, F.; Gallardo, A.; Bowker, M.; Wallenstein, M.; Quero, J.; Ochoa, V.; Gozalo, B.; García-Gómez, M.; Soliveres, S.; García-Palacios, P.; Berdugo, M.; Valencia, E.; Escolar, C.; Arredondo, T.; Barraza-Zepeda, C.; Bran, D.; Carreira, J.; Chaieb, M.; Conceição, A.; Derak, ... | 2013 | Modelación y Sistemas de Observación; Servicios Ecosistémicos | 10.1038/nature12670 | http://www.nature.com/doifinder/10.1038/nature12670 | 672-676 | Vol: 502 Issue: 7473 | 0028-0836 | Thomson Reuters ISI (SCIE) | English | The biogeochemical cycles of carbon (C), nitrogen (N) and phosphorus (P) are interlinked by primary production, respiration and decomposition in terrestrial ecosystems1. It has been suggested that the C, N and P cycles could become uncoupled under rapid climate change because of the different degrees of control exerted on the supply of these elements by biological and geochemical processes1, 2, 3, 4, 5. Climatic controls on biogeochemical cycles are particularly relevant in arid, semi-arid and dry sub-humid ecosystems (drylands) because their biological activity is mainly driven by water availability6, 7, 8. The increase in aridity predicted for the twenty-first century in many drylands worldwide9, 10, 11 may therefore threaten the balance between these cycles, differentially affecting the availability of essential nutrients12, 13, 14. Here we evaluate how aridity affects the balance between C, N and P in soils collected from 224 dryland sites from all continents except Antarctica. We find a negative effect of aridity on the concentration of soil organic C and total N, but a positive effect on the concentration of inorganic P. Aridity is negatively related to plant cover, which may favour the dominance of physical processes such as rock weathering, a major source of P to ecosystems, over biological processes that provide more C and N, such as litter decomposition12, 13, 14. Our findings suggest that any predicted increase in aridity with climate change will probably reduce the concentrations of N and C in global drylands, but increase that of P. These changes would uncouple the C, N and P cycles in drylands and could negatively affect the provision of key services provided by these ecosystems. | |
| Historical and idealized climate model experiments: an intercomparison of Earth system models of intermediate complexity | Climate of the Past | Eby, M.; Weaver, A.; Alexander, K.; Zickfeld, K.; Abe-Ouchi, A.; Cimatoribus, A.; Crespin, E.; Drijfhout, S.; Edwards, N.; Eliseev, A.; Feulner, G.; Fichefet, T.; Forest, C.; Goosse, H.; Holden, P.; Joos, F.; Kawamiya, M.; Kicklighter, D.; Kienert, H.; Matsumoto, K.; Mokhov, I.; Monier, E.; Olsen, S... | 2013 | Modelación y Sistemas de Observación | 10.5194/cp-9-1111-2013 | http://www.clim-past.net/9/1111/2013/ | 1111-1140 | Vol: 9 Issue: 3 | 1814-9324 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Both historical and idealized climate model experiments are performed with a variety of Earth system models of intermediate complexity (EMICs) as part of a community contribution to the Intergovernmental Panel on Climate Change Fifth Assessment Report. Historical simulations start at 850 CE and continue through to 2005. The standard simulations include changes in forcing from solar luminosity, Earth's orbital configuration, CO2, additional greenhouse gases, land use, and sulphate and volcanic aerosols. In spite of very different modelled pre-industrial global surface air temperatures, overall 20th century trends in surface air temperature and carbon uptake are reasonably well simulated when compared to observed trends. Land carbon fluxes show much more variation between models than ocean carbon fluxes, and recent land fluxes appear to be slightly underestimated. It is possible that recent modelled climate trends or climate–carbon feedbacks are overestimated resulting in too much land carbon loss or that carbon uptake due to CO2 and/or nitrogen fertilization is underestimated. Several one thousand year long, idealized, 2 × and 4 × CO2 experiments are used to quantify standard model characteristics, including transient and equilibrium climate sensitivities, and climate–carbon feedbacks. The values from EMICs generally fall within the range given by general circulation models. Seven additional historical simulations, each including a single specified forcing, are used to assess the contributions of different climate forcings to the overall climate and carbon cycle response. The response of surface air temperature is the linear sum of the individual forcings, while the carbon cycle response shows a non-linear interaction between land-use change and CO2 forcings for some models. Finally, the preindustrial portions of the last millennium simulations are used to assess historical model carbon-climate feedbacks. Given the specified forcing, there is a tendency for the EMICs to underestimate the drop in surface air temperature and CO2 between the Medieval Climate Anomaly and the Little Ice Age estimated from palaeoclimate reconstructions. This in turn could be a result of unforced variability within the climate system, uncertainty in the reconstructions of temperature and CO2, errors in the reconstructions of forcing used to drive the models, or the incomplete representation of certain processes within the models. Given the forcing datasets used in this study, the models calculate significant land-use emissions over the pre-industrial period. This implies that land-use emissions might need to be taken into account, when making estimates of climate–carbon feedbacks from palaeoclimate reconstructions. |
| Biological N2O fixation in the Eastern South Pacific Ocean and marine cyanobacterial cultures. | PloS one | Farías, L.; Faúndez, J.; Fernández, C.; Cornejo, M.; Sanhueza, S.; Carrasco, C. | 2013 | Biogeoquímica | 10.1371/journal.pone.0063956 | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0063956 | art63956 | Vol: 8 Issue: 5 | 1932-6203 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | Despite the importance of nitrous oxide (N2O) in the global radiative balance and atmospheric ozone chemistry, its sources and sinks within the Earth's system are still poorly understood. In the ocean, N2O is produced by microbiological processes such as nitrification and partial denitrification, which account for about a third of global emissions. Conversely, complete denitrification (the dissimilative reduction of N2O to N2) under suboxic/anoxic conditions is the only known pathway accountable for N2O consumption in the ocean. In this work, it is demonstrated that the biological assimilation of N2O could be a significant pathway capable of directly transforming this gas into particulate organic nitrogen (PON). N2O is shown to be biologically fixed within the subtropical and tropical waters of the eastern South Pacific Ocean, under a wide range of oceanographic conditions and at rates ranging from 2 pmol N L(-1) d(-) to 14.8 nmol N L(-1) d(-1) (mean ± SE of 0.522 ± 1.06 nmol N L(-1) d(-1), n = 93). Additional assays revealed that cultured cyanobacterial strains of Trichodesmium (H-9 and IMS 101), and Crocosphaera (W-8501) have the capacity to directly fix N2O under laboratory conditions; suggesting that marine photoautotrophic diazotrophs could be using N2O as a substrate. This metabolic capacity however was absent in Synechococcus (RCC 1029). The findings presented here indicate that assimilative N2O fixation takes place under extreme environmental conditions (i.e., light, nutrient, oxygen) where both autotrophic (including cyanobacteria) and heterotrophic microbes appear to be involved. This process could provide a globally significant sink for atmospheric N2O which in turn affects the oceanic N2O inventory and may also represent a yet unexplored global oceanic source of fixed N. |
| CFD simulations of turbulent buoyant atmospheric flows over complex geometry: Solver development in OpenFOAM | Computers & Fluids | Flores, F.; Garreaud, R.; Muñoz, R. | 2013 | Dinámica del Clima; Modelación y Sistemas de Observación | 10.1016/j.compfluid.2013.04.029 | http://www.sciencedirect.com/science/article/pii/S0045793013001795 | 1-13 | Vol: 82 | 0045-7930 | Thomson Reuters ISI (SCIE) | English | This paper, first of a two-part work, presents an overview of the development of a computational fluid dynamics (CFD) solver in OpenFOAM platform to simulate the internal ventilation regime within an open pit including the effects of developed turbulence, buoyancy and stratification. To incorporate the effect of stratification in the simulations we have chosen a formulation that includes density as a variable in the system of equations, thus facilitating further study of buoyant flows. Given the importance of turbulence in this type of large-scale flows we have used Large Eddy Simulation (LES) to incorporate it in the calculation, using a Detached Eddy Simulation (DES) approach to solve the flow near walls. Specific initial and boundary conditions were defined. The results presented in this paper, including several tests of the solver where we compared our results with experimental or numerical data, have demonstrated the validity of using OpenFOAM to study this type of complex multiphysics problems. Especially advantageous in this regard are the flexibility provided by the modular structure of the code, the possibility of defining specific boundary and initial conditions for each case, and the ability of generating detailed meshes of complex geometries. Also we probed the benefits of using a DES approach, allowing us to solve developed turbulence and the interaction of the flow with detailed geometry. A second paper associated to this work will expose the application of the solver to large open pit mines, simulating the particular case of Chuquicamata, one of the largest open pit mines in the world, located in northern Chile. |
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| Methane production induced by dimethylsulfide in surface water of an upwelling ecosystem | Progress in Oceanography | Florez-Leiva, L.; Damm, E.; Farías, L. | 2013 | Biogeoquímica | 10.1016/j.pocean.2013.03.005 | http://www.sciencedirect.com/science/article/pii/S007966111300030X | 38–48 | Vol: 112-113 | 0079-6611 | Thomson Reuters ISI (SCIE) | English | Coastal upwelling ecosystems are areas of high productivity and strong outgassing, where most gases, such as N2O and CH4, are produced in subsurface waters by anaerobic metabolisms. We describe seasonal CH4 variation as well as potential mechanisms producing CH4 in surface waters of the central Chile upwelling ecosystem (36°S). Surface waters were always supersaturated in CH4 (from 125% up to 550%), showing a clear seasonal signal triggered by wind driven upwelling processes (austral spring-summer period), that matched with the periods of high chlorophyll-a and dimethylsulfoniopropionate (DMSP) levels. Methane cycling experiments, with/without the addition of dimethylsulfide (including 13C-DMS) and acetylene (a nonspecific inhibitor of CH4 oxidation) along with monthly measurements of CH4, DMSP and other oceanographic variables revealed that DMS can be a CH4 precursor. Net CH4 cycling rates (control) fluctuated between -0.64 and 1.44nmolL-1d-1. After the addition of acetylene, CH4 cycling rates almost duplicated relative to the control, suggesting a strong methanotrophic activity. With a spike of DMS, the net CH4 cycling rate significantly increased relative to the acetylene and control treatment. Additionally, the δ13C values of CH4 at the end of the incubations (after addition of 13C enriched-DMS) were changed, reaching -32‰ PDB compared to natural values between -44‰ and -46‰ PDB. These findings indicate that, in spite of the strong CH4 consumption by methanotrophs, this upwelling area is an important source of CH4 to the atmosphere. The effluxes are derived partially from in situ surface production and seem to be related to DMSP/DMS metabolism. © 2013 Elsevier Ltd. | |
| The acceleration of oceanic denitrification during deglacial warming | Nature Geoscience | Galbraith, E.; Kienast, M.; Albuquerque, A.; Altabet, M.; Batista, F.; Bianchi, D.; Calvert, S.; Contreras, S.; Crosta, X.; Pol-Holz, R.; Dubois, N.; Etourneau, J.; Francois, R.; Hsu, T.; Ivanochko, T.; Jaccard, S.; Kao, S.; Kiefer, T.; Kienast, S.; Lehmann, M.; Martinez, P.; McCarthy, M.; Meckler, ... | 2013 | Biogeoquímica | 10.1038/ngeo1832 | http://www.nature.com/ngeo/journal/v6/n7/full/ngeo1832.html | 579–584 | Vol: 6 Issue: 7 | 1752-0894 | Thomson Reuters ISI (SCIE) | English | Over much of the ocean’s surface, productivity and growth are limited by a scarcity of bioavailable nitrogen. Sedimentary δ15N records spanning the last deglaciation suggest marked shifts in the nitrogen cycle during this time, but the quantification of these changes has been hinderedby the complexity of nitrogen isotope cycling. Herewe present a database of δ15Nin sediments throughout the world’s oceans, including 2,329 modern seafloor samples, and 76 timeseries spanning the past 30,000 years. We showthat the δ15Nvalues of modern seafloor sediments are consistent with values predicted by our knowledge of nitrogen cycling in thewater column. Despite many local deglacial changes, the globally averaged δ15N values of sinking organic matter were similar during the Last Glacial Maximum and Early Holocene. Considering the global isotopic mass balance, we explain these observations with the following deglacial history of nitrogen inventory processes. During the Last Glacial Maximum, the nitrogen cycle was near steady state. During the deglaciation, denitrification in the pelagic water column accelerated. The flooding of continental shelves subsequently increased denitrification at the seafloor, and denitrification reached near steady-state conditions again in the Early Holocene.We use a recent parameterization of seafloor denitrification to estimate a 30–120% increase in benthic denitrification between 15,000 and 8,000 years ago. Based on the similarity of globally averaged δ15N values during the Last Glacial Maximum and Early Holocene, we infer that pelagic denitrification must have increased by a similar amount between the two steady states. | |
| Warm Winter Storms in Central Chile | Journal of Hydrometeorology | Garreaud, R. | 2013 | Dinámica del Clima | 10.1175/JHM-D-12-0135.1 | http://journals.ametsoc.org/doi/abs/10.1175/JHM-D-12-0135.1 | 1515–1534 | Vol: 14 Issue: 5 | 1525-755X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Central Chile is a densely populated region along the west coast of subtropical SouthAmerica (30°-36°S), limited to the east by the Andes. Precipitation is concentrated in austral winter, mostly associated with the passage of cold fronts. The freezing level over central Chile is typically between 1500 and 2500m when precipitation is present. In about a third of the cases, however, precipitation occurs accompanied by warm temperatures and freezing levels above 3000 m, leading to a sizeable increment in the pluvial area of Andean basins and setting the stage for hydrometeorological hazards. Here, warm winter storms in central Chile are studied, including a statistical description of their occurrence and an estimate of their hydrological impacts. Remote-sensed data and high-resolution reanalysis are used to explore the synoptic-scale environment of a typical case, generalized later by a compositing analysis. The structure of warm storms is also contrasted with that of the more recurrent cold cases. Precipitation during warm events occurs in the warm sector of a slow-moving cold front because of the intense moisture flux against the mountains in connection with a land-falling atmospheric river. This is in turn driven by a strong zonal jet aloft and reduced mechanical blocking upstream of the Andes. On a broader scale, a key element is the presence of a slowly moving anticyclone over the south Pacific, fostering advection of cold air intomidlatitudes. The intense and persistent zonal jet stretches a moist-air corridor from the central Pacific to the west coast of South America. © 2013 American Meteorological Society. |
| Large-Scale Control on the Patagonian Climate | Journal of Climate | Garreaud, R.; Lopez, P.; Minvielle, M.; Rojas, M. | 2013 | Dinámica del Clima; Modelación y Sistemas de Observación | 10.1175/JCLI-D-12-00001.1 | http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00001.1 | 215-230 | Vol: 26 Issue: 1 | 0894-8755 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | Patagonia, located in southern South America, is a vast and remote region holding a rich variety of past environmental records but a small number of meteorological stations. Precipitation over this region is mostly produced by disturbances embedded in the westerly flow and is strongly modified by the austral Andes. Uplift on the windward side leads to hyperhumid conditions along the Pacific coast and the western slope of the Andes; in contrast, downslope subsidence dries the eastern plains leading to arid, highly evaporative conditions.The authors investigate the dependence of Patagonia’s local climate (precipitation and near-surface air temperature) year-to-year variability on large-scale circulation anomalies using results from a 30-yr-long high-resolution numerical simulation. Variations of the low-level zonal wind account for a large fraction of the rainfall variability at synoptic and interannual time scales. Zonal wind also controls the amplitude of the air temperature annual cycle by changing the intensity of the seasonally varying temperature advection.The main modes of year-to-year variability of the zonal flow over southern South America are also investigated. Year round there is a dipole between mid- and high latitudes. The node separating wind anomalies of opposite sign migrates through the seasons, leading to a dipole over Patagonia during austral summer and a monopole during winter. Reanalysis data also suggests that westerly flow has mostly decreased over north-central Patagonia during the last four decades, causing a drying trend to the west of the Andes, but a modest increase is exhibited over the southern tip of the continent. |
| Carbon dioxide and climate impulse response functions for the computation of greenhouse gas metrics: a multi-model analysis | Atmospheric Chemistry and Physics | Joos, F.; Roth, R.; Fuglestvedt, J.; Peters, G.; Enting, I.; von Bloh, W.; Brovkin, V.; Burke, E.; Eby, M.; Edwards, N.; Friedrich, T.; Frölicher, T.; Halloran, P.; Holden, P.; Jones, C.; Kleinen, T.; Mackenzie, F.; Matsumoto, K.; Meinshausen, M.; Plattner, G.; Reisinger, A.; Segschneider, J.; Shaff... | 2013 | Modelación y Sistemas de Observación | 10.5194/acp-13-2793-2013 | http://www.atmos-chem-phys.net/13/2793/2013/ | 2793-2825 | Vol: 13 Issue: 5 | 1680-7316 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The responses of carbon dioxide (CO2) and other climate variables to an emission pulse of CO2 into the atmosphere are often used to compute the Global Warming Potential (GWP) and Global Temperature change Potential (GTP), to characterize the response timescales of Earth System models, and to build reduced-form models. In this carbon cycle-climate model intercomparison project, which spans the full model hierarchy, we quantify responses to emission pulses of different magnitudes injected under different conditions. The CO2 response shows the known rapid decline in the first few decades followed by a millennium-scale tail. For a 100 Gt-C emission pulse added to a constant CO2 concentration of 389 ppm, 25 ± 9% is still found in the atmosphere after 1000 yr; the ocean has absorbed 59 ± 12% and the land the remainder (16 ± 14%). The response in global mean surface air temperature is an increase by 0.20 ± 0.12 °C within the first twenty years; thereafter and until year 1000, temperature decreases only slightly, whereas ocean heat content and sea level continue to rise. Our best estimate for the Absolute Global Warming Potential, given by the time-integrated response in CO2 at year 100 multiplied by its radiative efficiency, is 92.5 × 10−15 yr W m−2 per kg-CO2. This value very likely (5 to 95% confidence) lies within the range of (68 to 117) × 10−15 yr W m−2 per kg-CO2. Estimates for time-integrated response in CO2 published in the IPCC First, Second, and Fourth Assessment and our multi-model best estimate all agree within 15% during the first 100 yr. The integrated CO2 response, normalized by the pulse size, is lower for pre-industrial conditions, compared to present day, and lower for smaller pulses than larger pulses. In contrast, the response in temperature, sea level and ocean heat content is less sensitive to these choices. Although, choices in pulse size, background concentration, and model lead to uncertainties, the most important and subjective choice to determine AGWP of CO2 and GWP is the time horizon. |
| Los Lamini (Cetartiodactyla: Camelidae) extintos del yacimiento de Pilauco (Norpatagonia chilena): aspectos taxonómicos y tafonómicos preliminares | Estudios Geologicos | Labarca Encina, R.; Pino, M.; Recabarren, O. | 2013 | Modelación y Sistemas de Observación; Servicios Ecosistémicos | 10.3989/egeol.40862.219 | http://estudiosgeol.revistas.csic.es/index.php/estudiosgeol/article/view/881/913 | 255-269 | Vol: 69 Issue: 2 | 0367-0449 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | Spanish | We present a preliminary description and taxonomic assignment of the Lamini fossil remains recovered from the paleontological site of Pilauco (late Pleistocene) in southern Chile. Based on metric variables the fossils are temporarily asigned to cf. Hemiauchenia paradoxa Gervais & Ameghino 1880, waiting for new and more diagnostic remains. We present and discuss some taphonomic processes occurring within the site, starting from the study of the marks observed in the surface of the fossils, wich are consistent with the bog environment with occasional fluvial flooding described for the site. |
| El Niño modulations over the past seven centuries | Nature Climate Change | Li, J.; Xie, S.; Cook, E.; Morales, M.; Christie, D.; Johnson, N.; Chen, F.; D’Arrigo, R.; Fowler, A.; Gou, X.; Fang, K. | 2013 | Dinámica del Clima | 10.1038/nclimate1936 | http://www.nature.com/doifinder/10.1038/nclimate1936 | 822-826 | Vol: 3 Issue: 9 | 1758-678X | Thomson Reuters ISI (SCIE; SSCI) | English | Predicting how the El Niño/Southern Oscillation (ENSO) will change with global warming is of enormous importance to society 1-4. ENSO exhibits considerable natural variability at interdecadal–centennial timescales5. Instrumental records are too short to determine whether ENSO has changed6 and existing reconstructions are often developed without adequate tropical records. Here we present a seven-century-long ENSO reconstruction based on 2,222 tree-ring chronologies from both the tropics and mid-latitudes in both hemispheres. The inclusion of tropical records enables us to achieve unprecedented accuracy, as attested by high correlations with equatorial Pacific corals 7-8 and coherent modulation of global teleconnections that are consistent with an independent Northern Hemisphere temperature reconstruction9. Our data indicate that ENSO activity in the late twentieth century was anomalously high over the past seven centuries, suggestive of a response to continuing global warming. Climate models disagree on the ENSO response to global warming 3-4, suggesting that many models underestimate the sensitivity to radiative perturbations. Illustrating the radiative effect, our reconstruction reveals a robust ENSO response to large tropical eruptions, with anomalous cooling in the east-central tropical Pacific in the year of eruption, followed by anomalous warming one year after. Our observations provide crucial constraints for improving climate models and their future projections. | |
| Changes in the advection of Antarctic Intermediate Water to the northern Chilean coast during the last 970 kyr | Paleoceanography and Paleoclimatology | Martínez-Méndez, G.; Hebbeln, D.; Mohtadi, M.; Lamy, F.; De Pol-Holz, R.; Reyes-Macaya, D.; Freudenthal, T. | 2013 | Biogeoquímica | 10.1002/palo.20047 | http://onlinelibrary.wiley.com/doi/10.1002/palo.20047/abstract | 607–618 | Vol: 28 Issue: 4 | 2572-4517 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The Antarctic Intermediate Water (AAIW) is a key player in global-scale oceanic overturning processes and an important conduit for heat, fresh water, and carbon transport. The AAIW past variability is poorly understood mainly due to the lack of sedimentary archives at intermediate water depths. We present records of benthic stable isotopes from sediments retrieved with the seafloor drill rig MARUM-MeBo at 956 m water depth off northern Chile (GeoB15016, 27°29.48′S, 71°07.58′W) that extend back to 970 ka. The sediments at this site are presently deposited at the boundary between AAIW and Pacific Deep Water (PDW). For previous peak interglacials, our results reveal similar benthic δ13C values at site GeoB15016 and of a newly generated stack of benthic δ13C from various deep Pacific cores representing the "average PDW." This suggests, unlike today, the absence of AAIW at the site and the presence of nearly pure PDW. In contrast, more positive δ13C values at site GeoB15016 compared to the stack imply a considerable AAIW contribution during cold phases of interglacials and especially during glacials. Besides, we used three short sediment cores to reconstruct benthic δ13C values from the AAIW core during the last glacial and found a δ13C signature similar to today's. Assuming that this was the case also for the past 970 kyr, we demonstrate that sea level changes and latitudinal migrations of the AAIW formation site can only account for about 50% of the full range of past δ13C increases at site GeoB15016 during cold periods. Other processes that could explain the remaining of the positive δ13C anomalies are increases in glacial AAIW production and/or deeper convection of the AAIW with respect to preceding interglacials. Key Points Absence of AAIW off northern Chile during past peak interglacial periods Increase advection of AAIW to the northern Chilean margin during cold periods Present and LGM AAIW production similar and the highest since 970 ka ©2013. American Geophysical Union. All Rights Reserved. |
| Positive interactions between the lichen Usnea antarctica (Parmeliaceae) and the native flora in Maritime Antarctica | Journal of Vegetation Science | Molina-Montenegro, M.; Ricote-Martínez, N.; Muñoz-Ramírez, C.; Gómez-González, S.; Torres-Díaz, C.; Salgado-Luarte, C.; Gianoli, E. | 2013 | Modelación y Sistemas de Observación; Servicios Ecosistémicos | 10.1111/j.1654-1103.2012.01480.x | http://onlinelibrary.wiley.com/doi/10.1111/j.1654-1103.2012.01480.x/abstract | 463-472 | Vol: 24 Issue: 3 | 1100-9233 | Thomson Reuters ISI (SCIE) | English | Questions Is the macrolichen Usnea antarctica a ‘nurse’ species to Antarctic flora? Are positive plant–plant interactions more frequent than negative interactions in Antarctic ecosystems? Are microclimatic modifications by cushions of U. antarctica responsible for the nurse effect? Location Two sites in Antarctica: King George Island, South Shetland (62°11′ S, 58°56′ W; 62°11′ S, 58°59′ W). Methods We evaluated the association of plant species with U. antarctica cushions by recording species growing – in equivalent areas – within and outside U. antarctica cushions. Additionally, we performed transplant experiments with Deschampsia antarctica individuals to assess if U. antarctica cushions enhance plant survival. In both study sites we monitored temperature, moisture and nutrient status of soil outside and within the cushions to provide insights into potential mechanisms underlying possible interactions between U. antarctica and other plant species. Results Eight out of 13 species were positively associated with cushions of the widespread lichen U. antarctica, while only one species (U. aurantiaco-atra) showed a negative association with U. antarctica. Survival of Deschampsia was enhanced when growing associated with U. antarctica cushions. Our results indicate that cushions ameliorated the extreme conditions of Antarctic islands through increased temperature and soil moisture, decreased radiation and evaporative water loss and increased nutrient availability. Conclusions The nurse effect of U. antarctica is verified. Cushions of this macrolichen may be a key component in structuring the Antarctic landscape and maintaining local species richness, and their presence might influence range expansion of other species. |
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| Analysis and evolution of air quality monitoring networks using combined statistical information indexes | Tellus B: Chemical and Physical Meteorology | Osses, A.; Gallardo, L.; Faundez, T. | 2013 | Modelación y Sistemas de Observación | 10.3402/tellusb.v65i0.19822 | https://www.tandfonline.com/doi/full/10.3402/tellusb.v65i0.19822 | art19822 | Vol: 65 Issue: 1 | 0280-6509 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | In this work, we present combined statistical indexes for evaluating air quality monitoring networks based on concepts derived from the information theory and Kullback–Liebler divergence. More precisely, we introduce: (1) the standard measure of complementary mutual information or ‘specificity’ index; (2) a new measure of information gain or ‘representativity’ index; (3) the information gaps associated with the evolution of a network and (4) the normalised information distance used in clustering analysis. All these information concepts are illustrated by applying them to 14 yr of data collected by the air quality monitoring network in Santiago de Chile (33.5 S, 70.5 W, 500 m a.s.l.). We find that downtown stations, located in a relatively flat area of the Santiago basin, generally show high ‘representativity’ and low ‘specificity’, whereas the contrary is found for a station located in a canyon to the east of the basin, consistently with known emission and circulation patterns of Santiago. We also show interesting applications of information gain to the analysis of the evolution of a network, where the choice of background information is also discussed, and of mutual information distance to the classifications of stations. Our analyses show that information as those presented here should of course be used in a complementary way when addressing the analysis of an air quality network for planning and evaluation purposes. |
| The late Pleistocene Pilauco site, Osorno, south-central Chile | Quaternary International | Pino, M.; Chávez-Hoffmeister, M.; Navarro-Harris, X.; Labarca, R. | 2013 | Modelación y Sistemas de Observación; Servicios Ecosistémicos | 10.1016/j.quaint.2012.05.001 | http://www.sciencedirect.com/science/article/pii/S1040618212003199 | 3-12 | Vol: 299 | 1040-6182 | Thomson Reuters ISI (SCIE) | English | Paleontological and archaeological sites have frequently been found in open locations of the Intermediate Depression of south-central Chile. This paper presents the results of two field sampling seasons carried out at the Pilauco Site (ca. 39°S) and compares them with those of three well known sites in Chile: Quereo, Tagua-Tagua and Monte Verde, ca. 32°, 34° and 41°S, respectively. Stratigraphic data collected at Pilauco and the resulting radiocarbon age model suggest that before 12,540 ± 90 BP the old Damas River eroded an older volcaniclastic hill, which was followed by a bog formation in an ox-bow lake. The site was developing up to 11,004 ± 186 BP, the date of the youngest vertebrate fossil. Two younger peat beds seal the site. As in Tagua-Tagua and Monte Verde, Gomphotheres are the most represented megafauna. Fossils of Equidae, Camelidae, Cervidae, Mephitidae, Muridae, Myocastoridae and Xenarthra are also found in Pilauco. As a whole, 718 bones, 30 teeth and 11 coprolites represent the extinct and extant vertebrates. Preliminary taphonomic results suggest action of various agents in the bones, i.e. trampling, root etching, abrasion, and carnivore gnawing. The spatial analysis suggests the transfer of smaller anatomical units (e.g. bones of camelids and horses) and the rearrangement of some pieces comparatively large (e.g. gomphothere bones). Similar to the present day north Patagonian landscape, the area where Pilauco site is located had a variety of animal resources, plants and stones in an ecotone between hills, floodplains and wetlands. A total of 101 lithics were recorded: basalt and quartzite were collected from nearby fluvial deposits and dacitic obsidian from the local volcaniclastic deposits. Debitage is the most represented lithic item (75%); cores and marginal edge-trimmed artifacts represented 12 and 13%, respectively. Artifacts and flakes are spatially and temporality associated in the same PB-7 bed with high bone concentrations in some specific areas, between 361 and 424 cm of local altitude. This industry is characterized by a recurrent lithic expedite technology with production of flakes and chips which mastered marginal retouches over the bifacial trimming. This seems to be connected to strategic conditions of high resource diversity, especially of human groups with a high or medium mobility across land. Pilauco represents a site contemporaneous to Monte Verde related as well to the first human occupation in the southern cone of South America, but with higher mammal diversity. | |
| Climatic control of the biomass-burning decline in the Americas after ad 1500 | The Holocene | Power, M.; Mayle, F.; Bartlein, P.; Marlon, J.; Anderson, R.; Behling, H.; Brown, K.; Carcaillet, C.; Colombaroli, D.; Gavin, D.; Hallett, D.; Horn, S.; Kennedy, L.; Lane, C.; Long, C.; Moreno, P.; Paitre, C.; Robinson, G.; Taylor, Z.; Walsh, M. | 2013 | Dinámica del Clima; Modelación y Sistemas de Observación | 10.1177/0959683612450196 | http://hol.sagepub.com/content/23/1/3 | 3-13 | Vol: 23 Issue: 1 | 0959-6836 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | The significance and cause of the decline in biomass burning across the Americas after ad 1500 is a topic of considerable debate. We synthesized charcoal records (a proxy for biomass burning) from the Americas and from the remainder of the globe over the past 2000 years, and compared these with paleoclimatic records and population reconstructions. A distinct post-ad 1500 decrease in biomass burning is evident, not only in the Americas, but also globally, and both are similar in duration and timing to ‘Little Ice Age’ climate change. There is temporal and spatial variability in the expression of the biomass-burning decline across the Americas but, at a regional–continental scale, ‘Little Ice Age’ climate change was likely more important than indigenous population collapse in driving this decline. |
| Sensitivity of Southern Hemisphere circulation to LGM and 4 × CO2 climates | Geophysical Research Letters | Rojas, M. | 2013 | Modelación y Sistemas de Observación | 10.1002/grl.50195 | http://onlinelibrary.wiley.com/doi/10.1002/grl.50195/abstract | 965-970 | Vol: 40 Issue: 5 | 0094-8276 | Thomson Reuters ISI (SCIE) | English | This paper investigates the effect of Last Glacial Maximum (LGM) versus high CO2 world boundary condition on the Southern Hemisphere atmospheric circulation, in particular on the strength and latitudinal position of the near surface Southern Westerly Winds (SWW). PMIP2 and PMIP3 experiments, as well as the “abrupt 4 × CO2” simulations from CMIP5, were analyzed. Robust findings include poleward expansion of the Mean Meridional Circulation (MMC) and intensified and poleward-shifted SWW in the 4 × CO2 simulations (consistent with recent observations and 21st century climate change projections); and for the LGM, stronger and southward shifted northern hemisphere MMC, and weakened southern Hadley cell. However, six of the eight LGM simulations show a decrease in the SWW, the other two models simulate the opposite. A critical difference between the models is strong coupling between sea-ice extent, surface temperature gradients, SWW, and Ferrel cell in the two models with stronger and poleward-shifted SWW. | |
| Winter weather regimes over the Mediterranean region: their role for the regional climate and projected changes in the twenty-first century | Climate Dynamics | Rojas, M.; Li, L.; Kanakidou, M.; Hatzianastassiou, N.; Seze, G.; Treut, H. | 2013 | Modelación y Sistemas de Observación | 10.1007/s00382-013-1823-8 | http://link.springer.com/article/10.1007/s00382-013-1823-8 | 551-571 | Vol: 41 Issue: 3 | 0930-7575 | Thomson Reuters ISI (SCIE) | English | The winter time weather variability over the Mediterranean is studied in relation to the prevailing weather regimes (WRs) over the region. Using daily geopotential heights at 700 hPa from the ECMWF ERA40 Reanalysis Project and Cluster Analysis, four WRs are identified, in increasing order of frequency of occurrence, as cyclonic (22.0 %), zonal (24.8 %), meridional (25.2 %) and anticyclonic (28.0 %). The surface climate, cloud distribution and radiation patterns associated with these winter WRs are deduced from satellite (ISCCP) and other observational (E-OBS, ERA40) datasets. The LMDz atmosphere–ocean regional climate model is able to simulate successfully the same four Mediterranean weather regimes and reproduce the associated surface and atmospheric conditions for the present climate (1961–1990). Both observational- and LMDz-based computations show that the four Mediterranean weather regimes control the region’s weather and climate conditions during winter, exhibiting significant differences between them as for temperature, precipitation, cloudiness and radiation distributions within the region. Projections (2021–2050) of the winter Mediterranean weather and climate are obtained using the LMDz model and analysed in relation to the simulated changes in the four WRs. According to the SRES A1B emission scenario, a significant warming (between 2 and 4 °C) is projected to occur in the region, along with a precipitation decrease by 10–20 % in southern Europe, Mediterranean Sea and North Africa, against a 10 % precipitation increase in northern European areas. The projected changes in temperature and precipitation in the Mediterranean are explained by the model-predicted changes in the frequency of occurrence as well as in the intra-seasonal variability of the regional weather regimes. The anticyclonic configuration is projected to become more recurrent, contributing to the decreased precipitation over most of the basin, while the cyclonic and zonal ones become more sporadic, resulting in more days with below normal precipitation over most of the basin, and on the eastern part of the region, respectively. The changes in frequency and intra-seasonal variability highlights the usefulness of dynamics versus statistical downscaling techniques for climate change studies. | |
| Institutional Capacity for Climate Change Responses: An Examination of Construction and Pathways in Mexico City and Santiago | Environment and Planning C: Government and Policy | Romero-Lankao, P.; Hughes, S.; Rosas-Huerta, A.; Borquez, R.; Gnatz, D. | 2013 | Dimensión Humana | 10.1068/c12173 | http://journals.sagepub.com/doi/10.1068/c12173 | 785-805 | Vol: 31 Issue: 5 | 0263-774X | Thomson Reuters ISI (SSCI) | English | Scholars have focused on understanding the motivations behind urban authorities' efforts to respond to climate change, yet the determinants of institutional response capacity are less well known, particularly in Latin America. This paper develops a framework to understand the political–economic determinants of institutional response capacity through an examination of climate change governance in Mexico City and Santiago, Chile. We ask whether being a frontrunner (Mexico City) is an indicator of greater institutional response capacity. Although Mexico City has slightly higher levels of institutional capacity than Santiago, both are faced with similar challenges, such as fragmented governance arrangements, asymmetries in access to information, and top-down decision making. However, both also have similar opportunities, such as leadership, participation in transnational networks, and potential to integrate climate change goals into existing policy agendas. Examining urban climate change planning in isolation from other institutions is therefore likely to provide a false sense of a city's response capacity. | |
| Meteorological observations on the northern Chilean coast during VOCALS-REx | Atmospheric Chemistry and Physics | Rutllant, J.; Muñoz, R.; Garreaud, R. | 2013 | Dinámica del Clima | 10.5194/acp-13-3409-2013 | http://www.atmos-chem-phys.net/13/3409/2013/ | 3409-3422 | Vol: 13 Issue: 6 | 1680-7316 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access; Green Open Access | English | Surface coastal observations from two automatic weather stations at Paposo (~25° S) and radiosonde observations at Paposo and Iquique (~20° S) were carried out during VOCALS-REx (VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment). Within the coastal marine boundary layer (MBL), sea–land breezes are superimposed on the prevailing southerlies, resulting in light northeasterly winds from midnight to early morning and strong southwesterlies in the afternoon. The prevailing northerlies above the MBL and below the top of the Andes are modulated by the onshore-offshore (zonal) flow forced by the diurnal cycle of surface heating/cooling along the western slope of the Andes. The daytime phase of this diurnal cycle is consistent with an enhanced afternoon coastal subsidence manifested in afternoon warming near the top of the subsidence inversion (~1.8 K at 800 hPa), lowering (~130 m) of its base (top of the MBL), and clearing of coastal Sc (stratocumulus) clouds. Results from a numerical simulation of the atmospheric circulation in a mean zonal cross section over the study area capture the afternoon zonal wind divergence and resulting subsidence of about 2 cm s−1 along a narrow (~10 km) coastal strip maximizing at around 800 hPa. Day-to-day variability in the MBL depth during VOCALS-REx shows sub-synoptic oscillations, aside from two major disruptions in connection with a deep trough and a cutoff low, as described elsewhere. These oscillations are phase-locked to those in sea-level pressure and afternoon alongshore southerlies, as found in connection with coastal lows farther south. From 24-h forward trajectories issued from significant points at the coast and inland at the extremes of the diurnal cycle, it can be concluded that the strong mean daytime Andean pumping prevents any possibility of continental sulfur sources from reaching the free troposphere above the Sc cloud deck in at least a one-day timescale, under mean conditions. Conversely, coastal sources could contribute with sulfur aerosols preferentially in the morning, provided that the weak daytime inland flow becomes partially blocked by the coastal terrain. |
| Ozone distribution in the lower troposphere over complex terrain in Central Chile | Journal of Geophysical Research: Atmospheres | Seguel, R.; Mancilla, C.; Rondanelli, R.; Leiva, M.; Morales, R. | 2013 | Biogeoquímica | 10.1002/jgrd.50293 | http://doi.wiley.com/10.1002/jgrd.50293 | 2966-2980 | Vol: 118 Issue: 7 | 2169-897X | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | [1] Observations were performed in 12 communities of Central Chile in order to determine the horizontal gradients of ozone in the Santiago Basin and surrounding valleys. Higher ozone mixing ratios were found northeast of the Santiago Basin and included east of the Aconcagua Valley (~70 km from Santiago) suggesting that photochemical pollution produced in Santiago is capable of passing through the Chacabuco mountain chain (~1.3 km) and have impact downwind from the regions with the largest NOx and VOC emissions. To complement existing surface observations, ozonesonde and tethersonde campaigns were performed in the Santiago Basin and the Aconcagua Valley. The results suggest ozone can accumulate in layers aloft (e.g., >102 ppb at 2 km) similarly to layers observed in complex topography coastal regions like Southern California. Layers of significant ozone concentrations having a near surface origin were observed above the mixed layer and below the subsidence inversion base. We propose that the ozone in this residual layer can be transported large distances (at least to 70 km) to further penetrate into the local environment under conditions of a well-mixed boundary layer. |
| Carbon isotope records reveal precise timing of enhanced Southern Ocean upwelling during the last deglaciation | Nature Communications | Siani, G.; Michel, E.; De Pol-Holz, R.; DeVries, T.; Lamy, F.; Carel, M.; Isguder, G.; Dewilde, F.; Lourantou, A. | 2013 | Biogeoquímica | 10.1038/ncomms3758 | http://www.nature.com/ncomms/2013/131108/ncomms3758/full/ncomms3758.html | art2758 | Vol: 4 | 2041-1723 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access; Green Open Access | English | Upwelling of CO2 from the Southern Ocean may have played a key role in deglacial warming, but marine sediment studies are hindered by inaccurate chronologies. |
| Effects of volcanic and hydrologic processes on forest vegetation: Chaitén Volcano, Chile | Andean Geology | Swanson, F.; Jones, J.; Crisafulli, C.; Lara, A. | 2013 | Modelación y Sistemas de Observación; Servicios Ecosistémicos | 10.5027/andgeoV40n2-a10 | http://www.andeangeology.cl/index.php/revista1/article/view/2710 | 359-391 | Vol: 40 Issue: 2 | 0718-7106 | Thomson Reuters ISI (SCIE) | All Open Access; Gold Open Access | English | The 2008-2009 eruption of Chaitén Volcano (Chile) involved a variety of volcanic and associated hydrologic processes that damaged nearby forests. These processes included coarse (gravel) and fine (silt to sand) tephra fall, a laterally directed blast, fluvial deposition of remobilized tephra, a variety of low-temperature mass-movement processes, and a pyroclastic flow. Each of these geophysical processes constitutes a type of ecosystem disturbance which involves a distinctive suite of disturbance mechanisms, namely burial by tephra and sediment, heating, abrasion, impact force, and canopy loading (accumulation of tephra in tree crowns). Each process affected specific areas, and created patches and disturbance gradients in the forest landscape. Coarse tephra (‘gravel rain’, >5 cm depth) abraded foliage from tree canopies over an area of approximately 50 km2 north-northeast of the vent. Fine tephra (>10 cm depth) accumulated in tree crowns and led to breakage of branches in old forest and bowing of flexible, young trees over an area of about 480 km2. A directed blast down the north flank of the volcano damaged forest over an area of 4 km2. This blast zone included an area of tree removal near the crater rim, toppled forest farther down the slope, and standing, scorched forest around the blast perimeter. Fluvial deposition of >100 cm of remobilized tephra, beginning about 10 days after initiation of the eruption, buried floodplain forest in distinct, elongate streamside patches covering 5 km2 of the lower 19 km of the Rayas River and several km2 of the lower Chaitén River. Across this array of disturbance processes the fate of affected trees varied from complete mortality in the tree removal and pyroclastic flow areas, to no mortality in areas of thin tephra fall deposits. Tree damage included defoliation, loss of branches, snapping of tree trunks, abrasion of bark and ephiphytes, and uprooting. Damaged trees sprouted from epicormic buds located in trunks and branches, but sprouting varied over time among disturbance mechanisms and species. Although some effects of the Chaitén eruption are very similar to those from the 1980 eruption of Mount St. Helens (USA), interactions between biota and geophysical processes at Chaitén produced some unique effects. Examination of vegetation response helps interpret geophysical processes, and disturbance mechanisms influence early stages of biotic response to an eruption. |
| Long-Term Climate Change Commitment and Reversibility: An EMIC Intercomparison | Journal of Climate | Zickfeld, K.; Eby, M.; Weaver, A.; Alexander, K.; Crespin, E.; Edwards, N.; Eliseev, A.; Feulner, G.; Fichefet, T.; Forest, C.; Friedlingstein, P.; Goosse, H.; Holden, P.; Joos, F.; Kawamiya, M.; Kicklighter, D.; Kienert, H.; Matsumoto, K.; Mokhov, I.; Monier, E.; Olsen, S.; Pedersen, J.; Perrette, ... | 2013 | Modelación y Sistemas de Observación | 10.1175/JCLI-D-12-00584.1 | http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00584.1 | 5782-5809 | Vol: 26 Issue: 16 | 0894-8755 | Thomson Reuters ISI (SCIE) | All Open Access; Bronze Open Access | English | This paper summarizes the results of an intercomparison project with Earth System Models of Intermediate Complexity (EMICs) undertaken in support of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). The focus is on long-term climate projections designed to 1) quantify the climate change commitment of different radiative forcing trajectories and 2) explore the extent to which climate change is reversible on human time scales. All commitment simulations follow the four representative concentration pathways (RCPs) and their extensions to year 2300. Most EMICs simulate substantial surface air temperature and thermosteric sea level rise commitment following stabilization of the atmospheric composition at year-2300 levels. The meridional overturning circulation (MOC) is weakened temporarily and recovers to near-preindustrial values in most models for RCPs 2.6–6.0. The MOC weakening is more persistent for RCP8.5. Elimination of anthropogenic CO2 emissions after 2300 results in slowly decreasing atmospheric CO2 concentrations. At year 3000 atmospheric CO2 is still at more than half its year-2300 level in all EMICs for RCPs 4.5–8.5. Surface air temperature remains constant or decreases slightly and thermosteric sea level rise continues for centuries after elimination of CO2 emissions in all EMICs. Restoration of atmospheric CO2 from RCP to preindustrial levels over 100–1000 years requires large artificial removal of CO2 from the atmosphere and does not result in the simultaneous return to preindustrial climate conditions, as surface air temperature and sea level response exhibit a substantial time lag relative to atmospheric CO2. |
| Megacities and Large Urban Agglomerations in the Coastal Zone: Interactions Between Atmosphere, Land, and Marine Ecosystems | AMBIO | von Glasow, R.; Jickells, T.; Baklanov, A.; Carmichael, G.; Church, T.; Gallardo, L.; Hughes, C.; Kanakidou, M.; Liss, P.; Mee, L.; Raine, R.; Ramachandran, P.; Ramesh, R.; Sundseth, K.; Tsunogai, U.; Uematsu, M.; Zhu, T. | 2013 | Modelación y Sistemas de Observación | 10.1007/s13280-012-0343-9 | http://link.springer.com/article/10.1007/s13280-012-0343-9 | 13-28 | Vol: 42 Issue: 1 | 0044-7447 | Thomson Reuters ISI (SCIE) | All Open Access; Green Open Access | English | Megacities are not only important drivers for socio-economic development but also sources of environmental challenges. Many megacities and large urban agglomerations are located in the coastal zone where land, atmosphere, and ocean meet, posing multiple environmental challenges which we consider here. The atmospheric flow around megacities is complicated by urban heat island effects and topographic flows and sea breezes and influences air pollution and human health. The outflow of polluted air over the ocean perturbs biogeochemical processes. Contaminant inputs can damage downstream coastal zone ecosystem function and resources including fisheries, induce harmful algal blooms and feedback to the atmosphere via marine emissions. The scale of influence of megacities in the coastal zone is hundreds to thousands of kilometers in the atmosphere and tens to hundreds of kilometers in the ocean. We list research needs to further our understanding of coastal megacities with the ultimate aim to improve their environmental management. |