Research line:

Resilient cities

According to the United Nations, although cities covered less than 2 % of the earth’s surface in 2011, they consumed nearly 80% of the world’s energy and produced more than 60% of all carbon dioxide. This is particularly relevant in Chile, where nearly 90% of the population is considered urban, and approximately 50% of the population is concentrated in only three metropolitan areas: Santiago, Valparaíso and Concepción.

Several cities in Chile experience poor air quality during winter months, associated primarily with residential combustion and transportation. This explains in part the decision of the Chilean government to include plans to address air quality, as well as the introduction of a green tax that penalizes the use of diesel fuel, in its Nationally Determined Contribution (NDC) to the Paris Agreement. Furthermore, Chilean cities are considered highly vulnerable to the effects of climate change, particularly floods, landslides, droughts and heat waves and health impacts. Such threats and vulnerabilities are further exacerbated by social inequity and urban segregation.

 (CR)2 has developed and implemented tools (models, emission inventories, etc.) performed diagnostic and comprehensive analyses of urban issues. However, there is still a need for improved understanding of the intertwined dynamics of urban energy, land use, emissions, demographics, governance, and societal and biophysical processes.

To this effect, the research team at (CR)2 will examine urban impacts over varying timescales, from paleo climatic records of first human settlements in Chile, to projections of potential urban conditions in future climate scenarios.

The social scientists in our group will work towards understanding the ways in which society, from local communities to national authorities, is adapting to changes in extreme events, through research focused on current practices, their usefulness, the barriers to implementation, and the opportunities for improvement.









TítuloAutoresLínea de InvestigaciónAñoDOIAbstractRevistaISSNAccesoPáginasVolumenIndexKey Words
Overcoming energy poverty through micro-grids: An integrated framework for resilient, participatory sociotechnical transitionsValencia, Felipe; Billi, Marco; Urquiza, AnahíCiudades Resilientes; Gobernanza e Interfaz Ciencia y Política2021.010.1016/j.erss.2021.102030Nowadays, 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.Energy Research & Social Science22146296 Reuters ISIchile, energy poverty, micro-grids, participatory co-construction, socio-ecological resilience, socio-technical transitions, sustainability
The role of climate and disturbance regimes upon temperate rainforests during the Holocene: A stratigraphic perspective from Lago Fonk (∼40°S), northwestern PatagoniaHenríquez, Carla A.; Moreno, Patricio I.; Lambert, Fabrice; Alloway, Brent V.Ciudades Resilientes; Agua y Extremos2021.010.1016/j.quascirev.2021.106890Quaternary Science Reviews02773791 Reuters ISIcharcoal, explosives, fires, forestry, stratigraphy, volcanoes, centennial/millennial-scale variability, climate regime, disturbance regime, explosive volcanism, fire disturbance, holocenes, lake sediment cores, patagonia, pollen analysis, temperate rainforest, lakes, charcoal, climate variation, disturbance, explosive volcanism, fossil record, holocene, rainforest, stratigraphy, temperate forest, vegetation dynamics, chile, cumbria, england, lake district, longitudinal valley, patagonia, taiwan, united kingdom, eucryphia
Air pollution and COVID-19 lockdown in a large South American city: Santiago Metropolitan Area, ChileToro A., Richard; Catalán, Francisco; Urdanivia, Francesco R.; Rojas, Jhojan P.; Manzano, Carlos A.; Seguel, Rodrigo; Gallardo, Laura; Osses, Mauricio; Pantoja, Nicolás; Leiva-Guzman, Manuel A.Ciudades Resilientes2021.010.1016/j.uclim.2021.100803The 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.Urban Climate22120955 Reuters ISIcovid-19 lockdown, traffic emission rates, urban air quality
Radiocarbon bomb-peak signal in tree-rings from the tropical Andes register low latitude atmospheric dynamics in the Southern HemisphereAncapichún, Santiago; De Pol-Holz, Ricardo; Christie, Duncan A.; Santos, Guaciara M.; Collado-Fabbri, Silvana; Garreaud, René; Lambert, Fabrice; Orfanoz-Cheuquelaf, Andrea; Rojas, Maisa; Southon, John; Turnbull, Jocelyn C.; Creasman, Pearce PaulCiudades Resilientes; Agua y Extremos; Gobernanza e Interfaz Ciencia y Política2021.010.1016/j.scitotenv.2021.145126South 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.Science of The Total Environment00489697 Reuters ISIboundary layers, carbon, forestry, topography, tropics, atmospheric dynamics, carbon reservoirs, continental carbons, geographical provenances, latitudinal gradients, southern hemisphere, tropical climates, upper troposphere, bombs (ordnance), carbon 14, atmospheric circulation, atmospheric dynamics, atmospheric modeling, carbon isotope, latitudinal gradient, paleoclimate, radiocarbon dating, southern hemisphere, tree ring, amazonas (brazil), araucaria, araucaria angustifolia, article, atmosphere, atmospheric circulation, bomb, bomb signal, carbon reservoir effect, chile, controlled study, environmental impact, environmental parameters, geographic distribution, latitude, new zealand, nonhuman, pacific ocean, plant structures, polylepis tarapacana, priority journal, rosaceae, southern hemisphere, surface topography, topography, tree ring, troposphere, turnover rate, bomb, brazil, sea, tree, amazon basin, andes, brazil, new zealand, pacific ocean, bombs, brazil, oceans and seas, pacific ocean, trees
Permafrost evolution in a mountain catchment near Santiago de ChileRuiz Pereira, S.; Marquardt, C.; Beriain, E.; Lambert, F.Ciudades Resilientes2021.010.1016/j.jsames.2021.103293The 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.Journal of South American Earth Sciences08959811 Reuters ISIaggradation, catchment, environmental degradation, mountain environment, permafrost, solar radiation, surface temperature, aconcagua, andes, argentina, chile, cordillera principal, metropolitana, santiago [metropolitana]
Evaluating adaptation to drought in a changing climate: experience at the local scale in the Aconcagua ValleyAldunce, Paulina; Lillo-Ortega, Gloria; Araya-Valenzuela, Dámare; Maldonado-Portilla, Pamela; Gallardo, LauraCiudades Resilientes; Agua y Extremos2021.010.1080/17565529.2021.1893150Since 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.Climate and Development1756-5529, 1756-5537 Reuters ISIchile, climate change, drought, evaluation of adaptation, index for the usefulness of adaptation practices (iupa)
The state of science on severe air pollution episodes: Quantitative and qualitative analysisMorawska, Lidia; Zhu, Tong; Liu, Nairui; Amouei Torkmahalleh, Mehdi; de Fatima Andrade, Maria; Barratt, Benjamin; Broomandi, Parya; Buonanno, Giorgio; Carlos Belalcazar Ceron, Luis; Chen, Jianmin; Cheng, Yan; Evans, Greg; Gavidia, Mario; Guo, Hai; Hanigan, Ivan; Hu, Min; Jeong, Cheol H.; Kelly, Frank; Gallardo, Laura; Kumar, Prashant; Lyu, Xiaopu; Mullins, Benjamin J.; Nordstrøm, Claus; Pereira, Gavin; Querol, Xavier; Yezid Rojas Roa, Nestor; Russell, Armistead; Thompson, Helen; Wang, Hao; Wang, Lina; Wang, Tao; Wierzbicka, Aneta; Xue, Tao; Ye, CelineCiudades Resilientes2021.010.1016/j.envint.2021.106732Severe 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.Environment International01604120 Reuters ISIclimate change, air pollution episodes, anthropogenic sources, fine particles (pm$-2.5$/), formation of secondary pollutant, mitigating air pollutant, pollution emissions, pollution episodes, quantitative and qualitative analysis, severe air pollution event, urban air pollution, air pollution, accuracy assessment, atmospheric pollution, emission, episodic event, forecasting method, human activity, qualitative analysis, quantitative analysis, trend analysis, urban pollution, air pollutant, article, climate change, desert, forecasting, human, meteorology, qualitative analysis, quantitative analysis, wildfire
Forecasting PM2.5 levels in Santiago de Chile using deep learning neural networksMenares, Camilo; Perez, Patricio; Parraguez, Santiago; Fleming, Zoë L.Ciudades Resilientes2021.010.1016/j.uclim.2021.100906Air 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.Urban Climate22120955 Reuters ISIair quality forecasting, deep neural networks, fine particulate matter, lstm, machine learning, meteorology forecast
Long-Term Exposure to Fine and Coarse Particulate Matter and COVID-19 Incidence and Mortality Rate in Chile during 2020Valdés Salgado, Macarena; Smith, Pamela; Opazo, Mariel A.; Huneeus, NicolásCiudades Resilientes2021.010.3390/ijerph18147409Background: 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.International Journal of Environmental Research and Public Health1660-4601 Reuters ISIcovid-19, environmental risk, health impact, health risk, mortality, particulate matter, public health, air pollution, article, chile, climate, concentration (parameter), controlled study, coronavirus disease 2019, demography, environmental indicator, epidemiological data, human, incidence, long term exposure, major clinical study, mortality rate, pandemic, pm10 exposure, pm2.5 exposure, population size, severe acute respiratory syndrome coronavirus 2, social aspect, south america, adverse event, air pollutant, air pollution, environmental exposure, epidemiology, incidence, mortality, particulate matter, south america, sars coronavirus, air pollutants, air pollution, chile, covid-19, environmental exposure, humans, incidence, mortality, pandemics, particulate matter, sars-cov-2
Road Traffic Noise on the Santa Marta City Tourist RouteJiménez-Uribe, Dámaris A.; Daniels, Darwin; Fleming, Zoë L.; Vélez-Pereira, Andrés M.Ciudades Resilientes2021.010.3390/app11167196The 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).Applied Sciences2076-3417 Reuters ISIacoustic pollution, analysis of variance, field measurements, freeway, traffic flow dynamics
Assessment of Cardiovascular Risk in Women with Periodontal Diseases According to C-reactive Protein LevelsDa Venezia, Claudia; Hussein, Nayib; Hernández, Marcela; Contreras, Johanna; Morales, Alicia; Valdés, Macarena; Rojas, Francisca; Matamala, Loreto; Hernández-Ríos, PatriciaCiudades Resilientes2021.010.3390/biom11081238Cardiovascular 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.Biomolecules2218-273X Reuters ISIc reactive protein, cholesterol, hemoglobin a1c, high density lipoprotein cholesterol, lipid, low density lipoprotein cholesterol, triacylglycerol, adult, article, blood sampling, body mass, cardiovascular risk factor, cephalic vein, cholesterol blood level, confidence interval, controlled study, data analysis, diabetes mellitus, diagnostic test accuracy study, diastolic blood pressure, dyslipidemia, educational status, fasting, female, gingival index, gingivitis, high density lipoprotein cholesterol level, human, hypertension, immunoassay, low density lipoprotein cholesterol level, major clinical study, obesity, periodontal disease, periodontitis, physical examination, protein blood level, retrospective study, smoking, systolic blood pressure, triacylglycerol blood level
Validation of 4D Flow based relative pressure maps in aortic flowsNolte, David; Urbina, Jesús; Sotelo, Julio; Sok, Leo; Montalba, Cristian; Valverde, Israel; Osses, Axel; Uribe, Sergio; Bertoglio, CristóbalCiudades Resilientes2021.010.1016/ 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.Medical Image Analysis13618415 Reuters ISIdiagnosis, hospital data processing, navier stokes equations, phantoms, reynolds number, aortic coarctation, convective flow, lower resolution, lumen segmentations, pressure differences, spatially resolved, stokes equations, synthetic noise, blood vessels, adult, aortic coarctation, aortic flow, article, case report, catheterization, clinical article, female, flow measurement, four-dimensional imaging, hemodynamic parameters, human, image analysis, male, nuclear magnetic resonance imaging, patient coding, pressure gradient, pressure measurement
Present‐Day Patagonian Dust Emissions: Combining Surface Visibility, Mass Flux, and Reanalysis DataCosentino, N. J.; Gaiero, D. M.; Lambert, F.Ciudades Resilientes2021.010.1029/2020JD034459The 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.Journal of Geophysical Research: Atmospheres2169-897X, 2169-8996 Reuters ISIatmospheric pollution, long range transport, mass transfer, mineral dust, pollutant source, pollution monitoring, visibility, antarctica, patagonia, south america
A global observational analysis to understand changes in air quality during exceptionally low anthropogenic emission conditionsSokhi, Ranjeet S.; Singh, Vikas; Querol, Xavier; Finardi, Sandro; Targino, Admir Créso; Andrade, Maria de Fatima; Pavlovic, Radenko; Garland, Rebecca M.; Massagué, Jordi; Kong, Shaofei; Baklanov, Alexander; Ren, Lu; Tarasova, Oksana; Carmichael, Greg; Peuch, Vincent-Henri; Anand, Vrinda; Arbilla, Graciela; Badali, Kaitlin; Beig, Gufran; Belalcazar, Luis Carlos; Bolignano, Andrea; Brimblecombe, Peter; Camacho, Patricia; Casallas, Alejandro; Charland, Jean-Pierre; Choi, Jason; Chourdakis, Eleftherios; Coll, Isabelle; Collins, Marty; Cyrys, Josef; da Silva, Cleyton Martins; Di Giosa, Alessandro Domenico; Di Leo, Anna; Ferro, Camilo; Gavidia-Calderon, Mario; Gayen, Amiya; Ginzburg, Alexander; Godefroy, Fabrice; Gonzalez, Yuri Alexandra; Guevara-Luna, Marco; Haque, Sk. Mafizul; Havenga, Henno; Herod, Dennis; Hõrrak, Urmas; Hussein, Tareq; Ibarra, Sergio; Jaimes, Monica; Kaasik, Marko; Khaiwal, Ravindra; Kim, Jhoon; Kousa, Anu; Kukkonen, Jaakko; Kulmala, Markku; Kuula, Joel; La Violette, Nathalie; Lanzani, Guido; Liu, Xi; MacDougall, Stephanie; Manseau, Patrick M.; Marchegiani, Giada; McDonald, Brian; Mishra, Swasti Vardhan; Molina, Luisa T.; Mooibroek, Dennis; Mor, Suman; Moussiopoulos, Nicolas; Murena, Fabio; Niemi, Jarkko V.; Noe, Steffen; Nogueira, Thiago; Norman, Michael; Pérez-Camaño, Juan Luis; Petäjä, Tuukka; Piketh, Stuart; Rathod, Aditi; Reid, Ken; Retama, Armando; Rivera, Olivia; Rojas, Néstor Y.; Rojas-Quincho, Jhojan P.; San José, Roberto; Sánchez, Odón; Seguel, Rodrigo J.; Sillanpää, Salla; Su, Yushan; Tapper, Nigel; Terrazas, Antonio; Timonen, Hilkka; Toscano, Domenico; Tsegas, George; Velders, Guus J.M.; Vlachokostas, Christos; von Schneidemesser, Erika; Vpm, Rajasree; Yadav, Ravi; Zalakeviciute, Rasa; Zavala, MiguelCiudades Resilientes2021.010.1016/j.envint.2021.106818This 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.Environment International01604120 Reuters ISIatmospheric movements, carbon monoxide, geographical regions, nitrogen oxides, ozone, particles (particulate matter), quality control, sulfur dioxide, % reductions, air pollutants, biomass-burning, covid-19, nitrogen dioxides, no $-2$, observational analysis, particulate matter, pm$-2.5$, sulphur dioxide, air quality, air quality, atmospheric pollution, carbon monoxide, concentration (composition), covid-19, nitrogen dioxide, ozone, particulate matter, sulfur dioxide
Landscape Engineering Impacts the Long-Term Stability of Agricultural PopulationsFreeman, Jacob; Anderies, John M.; Beckman, Noelle G.; Robinson, Erick; Baggio, Jacopo A.; Bird, Darcy; Nicholson, Christopher; Finley, Judson Byrd; Capriles, José M.; Gil, Adolfo F.; Byers, David; Gayo, Eugenia; Latorre, ClaudioCiudades Resilientes2021.010.1007/s10745-021-00242-zExplaining 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.Human Ecology0300-7839, 1572-9915 Reuters ISIhuman population ecology, intensification, population stability, radiocarbon, resilience
An Integrated Framework to Streamline Resilience in the Context of Urban Climate Risk AssessmentUrquiza, A.; Amigo, C.; Billi, M.; Calvo, R.; Gallardo, L.; Neira, C. I.; Rojas, M.Ciudades Resilientes; Gobernanza2021.010.1029/2020EF001508Cities 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.Earth's Future2328-4277, 2328-4277 Reuters ISIclimate risk, ecosystem services, polycentric governance, socio-ecological systems, systems-of-systems, urban resilience
Paving the road for electric vehicles: Lessons from a randomized experiment in an introduction stage marketGuevara, C. Angelo; Figueroa, Esteban; Munizaga, Marcela A.Ciudades Resilientes2021.010.1016/j.tra.2021.09.011We 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.Transportation Research Part A: Policy and Practice09658564 Reuters ISIpublic policy, acquisition programmes, driving range, electric distribution company, environmental attitudes, focus groups, group users, maintenance cost, randomized experiments, stated preference surveys, stated preferences, electric vehicles
Global resilience models and territories of the South. A critical reviewMarin, JulietteCiudades Resilientes2021.010.1016/j.ijdrr.2021.102541The 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.International Journal of Disaster Risk Reduction22124209 Reuters ISIglobal south, literature review, sustainability, urban resilience
Study of the urban microclimate using thermal UAV. The case of the mid-sized cities of Arica (arid) and Curicó (Mediterranean), ChileSmith, Pamela; Sarricolea, Pablo; Peralta, Orlando; Aguila, Juan Pablo; Thomas, FelipeCiudades Resilientes2021.010.1016/j.buildenv.2021.108372The 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.Building and Environment03601323 Reuters ISIcosts, drones, remote sensing, satellite imagery, climate parameters, climate studies, field works, mid-sized city, surface emissions, surface temperatures, thermal, unmanned aerial vehicle, urban climates, urban microclimate, antennas
Overcoming energy poverty through micro-grids: An integrated framework for resilient, participatory sociotechnical transitionsValencia, Felipe; Billi, Marco; Urquiza, AnahíCiudades Resilientes; Gobernanza e Interfaz Ciencia y Política2021.010.1016/j.erss.2021.102030Nowadays, 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.Energy Research & Social Science22146296 Reuters ISIchile, energy poverty, micro-grids, participatory co-construction, socio-ecological resilience, socio-technical transitions, sustainability
Procurement of camelid fiber in the hyperarid Atacama Desert coast: Insights from stable isotopesGayo, E. M.; Martens, T.; Stuart-Williams, H.; Fenner, J.; Santoro, C.; Carter, C.; Cameron, J.Ciudades Resilientes10.1016/j.quaint.2019.12.008Pastoralism 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).Quaternary International10406182 Reuters ISIanimal husbandry, archaeology, arid environment, byproduct, hunter-gatherer, pastoralism, prehistoric, stable isotope, ungulate, atacama desert, chile, animalia, camelidae
Investigating the regional contributions to air pollution in Beijing: a dispersion modelling study using CO as a tracerPanagi, Marios; Fleming, Zoë L.; Monks, Paul S.; Ashfold, Matthew J.; Wild, Oliver; Hollaway, Michael; Zhang, Qiang; Squires, Freya A.; Vande Hey, Joshua D.Ciudades Resilientes2020.010.5194/acp-20-2825-2020Abstract. 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.Atmospheric Chemistry and Physics1680-7324 Reuters ISIair mass, air quality, atmospheric modeling, atmospheric pollution, carbon monoxide, emission inventory, meteorology, tracer, beijing [beijing (ads)], beijing [china], china, hebei, tianjin
Soccer games and record-breaking PM2.5 pollution events in Santiago, ChileLapere, Rémy; Menut, Laurent; Mailler, Sylvain; Huneeus, NicolásCiudades Resilientes2020.010.5194/acp-20-4681-2020Abstract. 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.Atmospheric Chemistry and Physics1680-7324 Reuters ISIair quality, atmospheric chemistry, atmospheric pollution, concentration (composition), emission inventory, metropolitan area, particulate matter, pollutant source, pollution control, pollution incidence, sport, urban atmosphere, urban pollution, winter, chile, metropolitana
El Formativo en Tarapacá (3000-1000 aP): Arqueología, naturaleza y cultura en la Pampa del Tamarugal, Desierto de Atacama, norte de ChileUribe, Mauricio; Angelo, Dante; Capriles, José; Castro, Victoria; de Porras, María Eugenia; García, Magdalena; Gayo, Eugenia; González, Josefina; Herrera, María José; Izaurieta, Roberto; Maldonado, Antonio; Mandakovic, Valentina; McRostie, Virginia; Razeto, Jorge; Santana, Francisca; Santoro, Calogero; Valenzuela, Jimena; Vidal, AlejandraCiudades Resilientes2020.010.1017/laq.2019.92En este trabajo se describen las relaciones que las sociedades humanas establecieron con su entorno durante el período Formativo (3000-1000 aP) en la Pampa del Tamarugal, Desierto de Atacama, desde una perspectiva teórico-metodológica que pone el acento en el potencial del registro ecofactual. Éste, al mediar entre lo cultural y lo ambiental, proporciona información vital para una mejor comprensión de la relación entre naturaleza y cultura construida por estas sociedades. Queremos demostrar que este proceso forma parte de una larga historia de racionalización del desierto y de sus recursos silvestres, locales e introducidos, así como de la vivencia particular que tuvieron estas comunidades andinas. Por consiguiente, proponemos que la intervención humana en la Pampa del Tamarugal puede ser entendida como un cambio no sólo ecológico y económico, sino también cosmológico. , 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.Latin American Antiquity1045-6635, 2325-5080 Reuters ISIarqueobotánica, arqueología simétrica, formativo, palabras claveandes centro-sur, tarapacá, zooarqueología
Mathematical Modeling for 2D Light--Sheet Fluorescence Microscopy image reconstructionCueva, Evelyn; Courdurier, Matias; Osses, Axel; Castañeda, Victor; Palacios, Benjamin; Härtel, SteffenCiudades Resilientes2020.010.1088/1361-6420/ab80d8Inverse Problems0266-5611, 1361-6420 Reuters ISIcameras, fluorescence, fluorescence microscopy, image reconstruction, iterative methods, light, linear systems, molecules, direct acquisition, excitation process, fluorescence microscopy images, fluorescent molecules, numerical experiments, regularized method, sparse linear systems, transport equation, inverse problems
MMP-8, TRAP-5, and OPG Levels in GCF Diagnostic Potential to Discriminate between Healthy Patients’, Mild and Severe Periodontitis SitesHernández, Marcela; Baeza, Mauricio; Contreras, Johanna; Sorsa, Timo; Tervahartiala, Taina; Valdés, Macarena; Chaparro, Alejandra; Hernández-Ríos, PatriciaCiudades Resilientes2020.010.3390/biom10111500Biomarkers 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.Biomolecules2218-273X Reuters ISIacid phosphatase tartrate resistant isoenzyme, neutrophil collagenase, osteoprotegerin, tartrate resistant acid phosphatase 5, unclassified drug, acid phosphatase tartrate resistant isoenzyme, acp5 protein, human, biological marker, mmp8 protein, human, neutrophil collagenase, osteoprotegerin, tnfrsf11b protein, human, adult, area under the curve, article, clinical article, controlled study, cross-sectional study, diagnostic accuracy, diagnostic test accuracy study, disease severity, female, fluorometry, gingivitis, human, immunoassay, male, middle aged, periodontal disease, periodontal pocket depth, periodontitis, receiver operating characteristic, sensitivity and specificity, time resolved spectroscopy, blood, chronic periodontitis, differential diagnosis, genetics, gingivitis, metabolism, pathology, periodontitis, severity of illness index, adult, biomarkers, chronic periodontitis, diagnosis, differential, female, gingival crevicular fluid, humans, male, matrix metalloproteinase 8, middle aged, osteoprotegerin, periodontitis, severity of illness index, tartrate-resistant acid phosphatase
Landscape evolution and the environmental context of human occupation of the southern pampa del tamarugal, Atacama Desert, ChileWorkman, T. Race; Rech, Jason A.; Gayó, Eugenia M.; Santoro, Calogero M.; Ugalde, Paula C.; De Pol-Holz, Ricardo; Capriles, Jose M.; Latorre, ClaudioCiudades Resilientes2020.010.1016/j.quascirev.2020.106502As 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.Quaternary Science Reviews02773791 Reuters ISIagricultural robots, banks (bodies of water), deposition, drought, ecology, employment, environmental technology, floods, groundwater, investments, natural resources, population statistics, wetlands, atacama desert , chile, cultural conventions, environmental change, environmental contexts, landscape evolutions, population densities, remotely sensed data, resource availability, biology, archaeological evidence, climate change, drought, floodplain, hunter-gatherer, landscape change, landscape evolution, natural resource, occupation, population density, precipitation (climatology), reconstruction, satellite data, wetland, andes, atacama desert, chile
Association between coal and firewood combustion and hospital admissions and mortality in Chile 2015 – An ecological approachParedes, María; Muñoz, María; Valdés Salgado, Macarena; Maldonado, AnaCiudades Resilientes2020.010.26444/aaem/125010Introduction 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.Annals of Agricultural and Environmental Medicine1232-1966, 1898-2263,125010,0,2.htmlThomson Reuters ISIcoal, coal, adult, all cause mortality, article, cardiovascular mortality, chile, combustion, cooking, female, firewood, heating, hospital admission, hospital mortality, hospitalization, household, human, male, morbidity, mortality rate, poverty, prevalence, trend study, wood, adverse event, cardiovascular disease, epidemiology, indoor air pollution, mortality, respiratory tract disease, wood, air pollution, indoor, cardiovascular diseases, chile, coal, cooking, female, heating, hospital mortality, hospitalization, humans, male, respiratory tract diseases, wood
Ecology of the collapse of Rapa Nui societyLima, M.; Gayo, E. M.; Latorre, C.; Santoro, C. M.; Estay, S. A.; Cañellas-Boltà, N.; Margalef, O.; Giralt, S.; Sáez, A.; Pla-Rabes, S.; Chr. Stenseth, N.Ciudades Resilientes2020.010.1098/rspb.2020.0662Collapses 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’.Proceedings of the Royal Society B: Biological Sciences0962-8452, 1471-2954 Reuters ISIcarrying capacity, climate change, collapse, population decline, population dynamics, population modeling, prehistoric, radiocarbon dating, reconstruction, easter island
Two decades of ozone standard exceedances in Santiago de ChileSeguel, Rodrigo J.; Gallardo, Laura; Fleming, Zoë L.; Landeros, SofíaCiudades Resilientes2020.010.1007/s11869-020-00822-wAir Quality, Atmosphere & Health1873-9318, 1873-9326 Reuters ISIatmospheric pollution, carbon monoxide, climate change, exhaust emission, nitric oxide, ozone, spatiotemporal analysis, urban pollution, urban sprawl, urbanization, volatile organic compound, santiago [metropolitana]
13,000 years of sociocultural plant use in the Atacama Desert of northern ChileUgalde, Paula C.; McRostie, Virginia; Gayo, Eugenia M.; García, Magdalena; Latorre, Claudio; Santoro, Calogero M.Ciudades Resilientes2020.010.1007/s00334-020-00783-1Throughout 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.Vegetation History and Archaeobotany0939-6314, 1617-6278 Reuters ISIarchaeobotany, atacama desert, palaeoenvironments, plant management, socio-cultural change
Trends and emissions of six perfluorocarbons in the Northern Hemisphere and Southern HemisphereDroste, Elise S.; Adcock, Karina E.; Ashfold, Matthew J.; Chou, Charles; Fleming, Zoë; Fraser, Paul J.; Gooch, Lauren J.; Hind, Andrew J.; Langenfelds, Ray L.; Leedham Elvidge, Emma; Mohd Hanif, Norfazrin; O'Doherty, Simon; Oram, David E.; Ou-Yang, Chang-Feng; Panagi, Marios; Reeves, Claire E.; Sturges, William T.; Laube, Johannes C.Ciudades Resilientes2020.010.5194/acp-20-4787-2020Abstract. 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.Atmospheric Chemistry and Physics1680-7324 Reuters ISIatmospheric chemistry, concentration (composition), emission control, global warming, greenhouse gas, northern hemisphere, organofluorine, source apportionment, trend analysis, australia, cape grim, tasmania, united kingdom
Regional patterns and temporal evolution of ocean iron fertilization and CO2 drawdown during the last glacial terminationLambert, Fabrice; Opazo, Natalia; Ridgwell, Andy; Winckler, Gisela; Lamy, Frank; Shaffer, Gary; Kohfeld, Karen; Ohgaito, Rumi; Albani, Samuel; Abe-Ouchi, AyakoCiudades Resilientes2021.010.1016/j.epsl.2020.116675The 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.Earth and Planetary Science Letters0012821X Reuters ISIbiology, carbon dioxide, dust, earth (planet), glacial geology, global warming, surface waters, co2 concentration, earth system model of intermediate complexity, iron fertilization, last glacial maximum, last glacial terminations, northern hemispheres, southern hemisphere, temporal evolution, iron, carbon dioxide, dust, global warming, iron, last glacial maximum, northern hemisphere, paleoclimate, reconstruction, temporal evolution
Differences in the composition of organic aerosols between winter and summer in Beijing: a study by direct-infusion ultrahigh-resolution mass spectrometrySteimer, Sarah S.; Patton, Daniel J.; Vu, Tuan V.; Panagi, Marios; Monks, Paul S.; Harrison, Roy M.; Fleming, Zoë L.; Shi, Zongbo; Kalberer, MarkusCiudades Resilientes2020.010.5194/acp-20-13303-2020Abstract. 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.Atmospheric Chemistry and Physics1680-7324 Reuters ISIaerosol composition, biomass burning, concentration (composition), fossil fuel, mass spectrometry, particulate matter, sulfate, summer, winter, beijing [beijing (ads)], beijing [china], birmingham [birmingham (dst)], birmingham [england], china, england, united kingdom
A statistical physics approach to perform fast highly-resolved air quality simulations – A new step towards the meta-modelling of chemistry transport modelsBessagnet, Bertrand; Couvidat, Florian; Lemaire, VincentCiudades Resilientes2019.010.1016/j.envsoft.2019.02.017A 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.Environmental Modelling & Software13648152 Reuters ISIair quality, linear regression, machine learning, optical resolving power, ozone, statistics, air quality forecasting, air quality modelling, chemical transport models, chemistry transport model, criteria air pollutants, increment, meta model, simple linear regression, statistical physics, air quality, atmospheric modeling, atmospheric pollution, machine learning, methodology, ozone, particulate matter, regression analysis, simulation, statistical analysis
Assessment of landscape transformation in protected areasPereira, Sebastian Ruiz; Fernández, José; Herrera, José; Olea, JorgeCiudades Resilientes2021.010.1016/j.eiar.2020.106472Mountain 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.Environmental Impact Assessment Review01959255 Reuters ISIconservation, economic analysis, environmental impact assessments, environmental protection, uncertainty analysis, conceptual analysis, conservation management, economic transformation, environmental impact study, landscape assessments, landscape management, landscape values, protected areas, environmental impact, conceptual framework, conservation management, economic analysis, environmental impact assessment, legislation, protected area, uncertainty analysis, andes, chile
Increasing trends (2001–2018) in photochemical activity and secondary aerosols in Santiago, ChileMenares, Camilo; Gallardo, Laura; Kanakidou, Maria; Seguel, Rodrigo; Huneeus, NicolásCiudades Resilientes2020.010.1080/16000889.2020.1821512Despite 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.Tellus B: Chemical and Physical Meteorology1600-0889 Reuters ISIaerosol composition, aerosol formation, atmospheric chemistry, ozone, particulate matter, photochemistry, trend analysis, chile, metropolitana
Climate change perception, vulnerability, and readiness: inter-country variability and emerging patterns in Latin AmericaAzócar, Gabriela; Billi, Marco; Calvo, Rubén; Huneeus, Nicolas; Lagos, Marta; Sapiains, Rodolfo; Urquiza, AnahíCiudades Resilientes; Gobernanza e Interfaz Ciencia y Política2020.010.1007/s13412-020-00639-0In 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.Journal of Environmental Studies and Sciences2190-6483, 2190-6491 Reuters ISIadaptive management, climate change, perception, questionnaire survey, vulnerability, latin america
Evaluation of anthropogenic air pollutant emission inventories for South America at national and city scaleHuneeus, N.; Gon, Hugo Denier van der; Castesana, Paula; Menares, Camilo; Granier, Claire; Granier, Louise; Alonso, Marcelo; de Fatima Andrade, Maria; Dawidowski, Laura; Gallardo, Laura; Gomez, Dario; Klimont, Zbigniew; Janssens-Maenhout, Greet; Osses, Mauricio; Puliafito, S. Enrique; Rojas, Nestor; Ccoyllo, Odón Sánchez-; Tolvett, Sebastián; Ynoue, Rita YuriCiudades Resilientes10.1016/j.atmosenv.2020.117606Atmospheric Environment13522310 Reuters ISIair quality, atmospheric composition, climate change, cost effectiveness, air pollutant emission, air quality modeling, anthropogenic climate changes, anthropogenic emissions, emission inventories, greenhouse gases (ghg), national emission inventories, sectoral contribution, greenhouse gases, anthropogenic source, atmospheric pollution, climate change, emission inventory, greenhouse gas, human activity, megacity, pollutant source, united nations framework convention on climate change, air quality, argentina, article, brazil, chile, colombia, greenhouse gas, human, peru, urban area, argentina, brazil, chile, colombia, peru
Analysis of exposure to fine particulate matter using passive data from public transportTrewhela, Benjamín; Huneeus, Nicolás; Munizaga, Marcela; Mazzeo, Andrea; Menut, Laurent; Mailler, Sylvain; Valari, Myrto; Ordoñez, CesarCiudades Resilientes2019.010.1016/j.atmosenv.2019.116878The 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.Atmospheric Environment1352-2310 Reuters ISIair quality, carrier mobility, inverse problems, smart cards, exposure, extreme pollution events, fine particulate matter, pm2.5, public transport, public transport systems, socio-economic conditions, surface concentration, particles (particulate matter), ozone, air exposure, air quality, concentration (composition), health impact, ozone, particulate matter, public transport, socioeconomic conditions, air monitoring, air pollutant, air quality, article, chile, concentration (parameter), environmental exposure, income, model, particle size, particulate matter, population, priority journal, traffic and transport, urban area
Multidecadal environmental pollution in a mega-industrial area in central Chile registered by tree ringsMuñoz, Ariel A.; Klock-Barría, Karin; Sheppard, Paul R.; Aguilera-Betti, Isabella; Toledo-Guerrero, Isadora; Christie, Duncan A.; Gorena, Tamara; Gallardo, Laura; González-Reyes, Álvaro; Lara, Antonio; Lambert, Fabrice; Gayo, Eugenia; Barraza, Francisco; Chávez, Roberto O.Ciudades Resilientes; Agua y Extremos2019.010.1016/j.scitotenv.2019.133915Science of The Total Environment0048-9697 Reuters ISIair quality, aluminum alloys, pollution control, trace elements, trees (mathematics), baseline, dendrochemistry, industrial pollution, macrocarpa, trace metal, forestry, aluminum, arsenic, cadmium, chromium, cobalt, copper, iron, lead, molybdenum, silver, trace metal, vanadium, zinc, anthropogenic source, concentration (composition), decadal variation, dendrochronology, environmental change, soil pollution, soil quality, trace metal, tree ring, air monitoring, air pollution, air quality, article, biochemistry, chemical composition, chile, comparative study, controlled study, cupressus, cupressus macrocarpa, dendrochemistry, environmental impact, geographic distribution, human activities, industrial area, plant structures, priority journal, temporal analysis, tree ring, chemistry, environmental monitoring, industry, pollution, procedures, tree, chile, cupressus macrocarpa, chile, environmental monitoring, environmental pollution, industry, trees
A perched, high-elevation wetland complex in the Atacama Desert (northern Chile) and its implications for past human settlementSitzia, Luca; Gayo, Eugenia M.; Sepulveda, Marcela; González, Juan S.; Ibañez, Lucia; Queffelec, Alain; De Pol-Holz, RicardoCiudades Resilientes2019.010.1017/qua.2018.144A 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.Quaternary Research0033-5894 Reuters ISIdeposits, groundwater, sea level, volcanoes, atacama desert, central andes, holocenes, intermediate periods, tuff, volcanic ash, wetlands, formation mechanism, holocene, paleohydrology, paleosol, prehistoric, settlement pattern, tuff, volcanic ash, wetland, andes, atacama desert, chile
Elemental and Mineralogical Composition of the Western Andean Snow (18°S–41°S)Alfonso, Juan A.; Cordero, Raul R.; Rowe, Penny M.; Neshyba, Steven; Casassa, Gino; Carrasco, Jorge; MacDonell, Shelley; Lambert, Fabrice; Pizarro, Jaime; Fernandoy, Francisco; Feron, Sarah; Damiani, Alessandro; Llanillo, Pedro; Sepulveda, Edgardo; Jorquera, Jose; Garcia, Belkis; Carrera, Juan M.; Oyola, Pedro; Kang, Choong-MinCiudades Resilientes2019.010.1038/s41598-019-44516-5The 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).Scientific Reports2045-2322 Reuters ISI
FROM THE PACIFIC TO THE TROPICAL FORESTS: NETWORKS OF SOCIAL INTERACTION IN THE ATACAMA DESERT, LATE IN THE PLEISTOCENESantoro, Calogero M.; Gayo, Eugenia M.; Capriles, José M.; Rivadeneira, Marcelo M.; Herrera, Katherine A; Mandakovic, Valentina; Rallo, Mónica; Rech, Jason A.; Cases, Bárbara; Briones, Luis; Olguín, Laura; Valenzuela, Daniela; Borrero, Luis A.; Ugalde, Paula C.; Rothhammer, Francisco; Latorre, Claudio; Szpak, PaulCiudades Resilientes2019.010.4067/S0717-73562019005000602The 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.Chungará (Arica)0717-7356 Reuters ISIandes, andes, atacama desert, bosque tropical, costa del pacífico, desierto de atacama, local, pacific coast, redes de interacción locales, regional and pan-andean networks of interaction, regionales y pan-andinas, tropical forest
Dietary diverstiy in the Atacama desert during the Late intermediate period of northern ChileAlfonso-Durruty, Marta P.; Gayo, Eugenia M.; Standen, Vivien; Castro, Victoria; Latorre, Claudio; Santoro, Calogero M.; Valenzuela, DanielaCiudades Resilientes2019.010.1016/j.quascirev.2019.04.022The 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.Quaternary Science Reviews0277-3791 Reuters ISIecosystems, isotopes, landforms, marine biology, natural resources, pathology, archaeological site, atacama desert, coastal ecosystems, individual preference, intermediate periods, marine resources, stable isotopes, terrestrial resources, oceanography, archaeology, biomass, marine resource, pathology, prehistoric, stable isotope, atacama desert, chile, pacific ocean, zea mays
In-stream wetland deposits, megadroughts, and cultural change in the northern Atacama Desert, ChileTully, Craig D.; Rech, Jason A.; Workman, T. Race; Santoro, Calogero M.; Capriles, José M.; Gayo, Eugenia M.; Latorre, ClaudioCiudades Resilientes2019.010.1017/qua.2018.122A 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.Quaternary Research0033-5894 Reuters ISIdeposits, drought, groundwater, wetlands, atacama, atacama desert , chile, chile, climatic changes, cultural changes, megadroughts, regional climate changes, synoptic climatology, climate change, climate variation, climatology, cultural change, drought, fluvial deposit, paleoclimate, wetland, atacama desert, chile
Emergence of robust precipitation changes across crop production areas in the 21st centuryRojas, Maisa; Lambert, Fabrice; Ramirez-Villegas, Julian; Challinor, Andrew J.Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política2019.010.1073/pnas.1811463116A 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.Proceedings of the National Academy of Sciences0027-8424 Reuters ISIarticle, climate change, crop production, france, maize, nonhuman, precipitation, probability, rice, soybean, wheat, adaptation, biological model, crop, growth, development and aging, adaptation, physiological, climate change, crop production, crops, agricultural, models, biological
Anthropogenic drying in central-southern Chile evidenced by long-term observations and climate model simulationsBoisier, Juan P.; Alvarez-Garretón, Camila; Cordero, Raúl R.; Damiani, Alessandro; Gallardo, Laura; Garreaud, René D.; Lambert, Fabrice; Ramallo, Cinthya; Rojas, Maisa; Rondanelli, RobertoCiudades Resilientes; Zonas Costeras; Agua y Extremos; Gobernanza e Interfaz Ciencia y Política2018.010.1525/elementa.328The 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.Elementa: Science of the Anthropocene2325-1026 Reuters ISIanthropogenic effect, carbon emission, climate modeling, drought, greenhouse gas, long-term change, ozone depletion, simulation, streamflow, trend analysis, vulnerability, chile
What is the ‘Social’ in Climate Change Research? A Case Study on Scientific Representations from ChileBilli, Marco; Blanco, Gustavo; Urquiza, AnahíCiudades Resilientes; Gobernanza e Interfaz Ciencia y Política2019.010.1007/s11024-019-09369-2Over 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.Minerva0026-4695 Reuters ISIchile, climate change, literature meta-analysis, scientific black boxes, scientific representations, social dimensions
Black carbon and other light-absorbing impurities in snow in the Chilean AndesRowe, Penny M.; Cordero, Raul R.; Warren, Stephen G.; Stewart, Emily; Doherty, Sarah J.; Pankow, Alec; Schrempf, Michael; Casassa, Gino; Carrasco, Jorge; Pizarro, Jaime; MacDonell, Shelley; Damiani, Alessandro; Lambert, Fabrice; Rondanelli, Roberto; Huneeus, Nicolas; Fernandoy, Francisco; Neshyba, StevenCiudades Resilientes; Zonas Costeras2019.010.1038/s41598-019-39312-0Vertical 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).Scientific Reports2045-2322 Reuters ISI
Estimation of atmospheric total organic carbon (TOC) – paving the path towards carbon budget closureYang, Mingxi; Fleming, Zoë L.Ciudades Resilientes2019.010.5194/acp-19-459-2019The 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.Atmospheric Chemistry and Physics1680-7324 Reuters ISIaerosol, atmospheric chemistry, carbon budget, estimation method, human activity, oxidation, total organic carbon, volatile organic compound, united kingdom
Rare calcium chloride–rich soil and implications for the existence of liquid water in a hyperarid environmentPfeiffer, Marco; Latorre, Claudio; Gayo, Eugenia; Amundson, RonaldCiudades Resilientes2019.010.1130/G45642.1We 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.Geology0091-7613 Reuters ISIcalcium chloride, groundwater, organic carbon, sodium chloride, atacama desert, climatic conditions, land surface, liquid water, martian soils, shallow groundwater, total nitrogen, wet surfaces, soils, arid environment, climate conditions, mineral, mineralogy, soil water, atacama desert, chile
Geohistorical records of the Anthropocene in ChileGayo, E. M.; McRostie, V.; Campbell, R.; Flores, C.; Maldonado, A.; Uribe-Rodriguez, M.; Moreno, P. I.; Santoro, C.; Christie, D. A.; Muñoz, A. A.; Gallardo, L.Ciudades Resilientes; Agua y Extremos10.1525/elementa.353The 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.Elem Sci Anth2325-1026 Reuters ISIanthropocene, anthropogenic source, archaeology, biophysics, coevolution, colonization, complexity, heavy metal, historical record, landscape, metallurgy, paleoenvironment, social change
Dynamical downscaling over the complex terrain of southwest South America: present climate conditions and added value analysisBozkurt, Deniz; Rojas, Maisa; Boisier, Juan Pablo; Rondanelli, Roberto; Garreaud, René; Gallardo, LauraCiudades Resilientes; Zonas Costeras; Agua y Extremos; Gobernanza e Interfaz Ciencia y Política; Transversal2019.010.1007/s00382-019-04959-yThis 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.Climate Dynamics0930-7575 Reuters ISIclimate conditions, climate modeling, climate variation, complex terrain, downscaling, regional climate, spatial analysis, temporal analysis, andes, atacama desert, chile, patagonia, equus asinus
Perception of thermal comfort in outdoor public spaces in the medium-sized city of Chillán, Chile, during a warm summerSmith, Pamela; Henríquez, CristiánCiudades Resilientes2019.010.1016/j.uclim.2019.100525The 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.Urban Climate2212-0955 Reuters ISIenvironmental comfort, perceived thermal comfort, public space, socioeconomic status
Public Spaces as Climate Justice Places? Climate Quality in the City of Chillán, ChileSmith, Pamela; Henríquez, CristiánCiudades Resilientes2019.010.1089/env.2018.0041The 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 residentsEnvironmental Justice1939-4071 Reuters ISIclimate change, environmental conditions, environmental quality, periurban area, public space, quality of life, socioeconomic conditions, urban climate, urban growth, urban planning, urban population, bio bio, chile, chillan
Quality as a hidden dimension of energy poverty in middle-development countries. Literature review and case study from ChileUrquiza, Anahí; Amigo, Catalina; Billi, Marco; Calvo, Rubén; Labraña, Julio; Oyarzún, Tamara; Valencia, FelipeCiudades Resilientes2019.010.1016/j.enbuild.2019.109463The 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.Energy and Buildings0378-7788 Reuters ISIpublic policy, chile, development countries, energy access, energy equity, energy poverties, energy quality, developing countries
Glacier decline in the Central Andes (33°S): Context and magnitude from satellite and historical dataRuiz Pereira, Sebastian Felipe; Veettil, Bijeesh KozhikkodanCiudades Resilientes2019.010.1016/j.jsames.2019.102249Central 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 swath 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 Veettil).Journal of South American Earth Sciences 94 (2019) 102249Available online 27 June 20190895-9811/ © 2019 Elsevier Ltd. All rights reserved.TJournal of South American Earth Sciences0895-9811 Reuters ISIcryosphere, deglaciation, geological mapping, glacier, mountain region, satellite data, sentinel, andes
Recent wildfires in Central Chile: Detecting links between burned areas and population exposure in the wildland urban interfaceSarricolea, Pablo; Serrano-Notivoli, Roberto; Fuentealba, Magdalena; Hernández-Mora, Marina; de la Barrera, Francisco; Smith, Pamela; Meseguer-Ruiz, ÓliverCiudades Resilientes2020.010.1016/j.scitotenv.2019.135894Wildfires 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.Science of The Total Environment00489697 Reuters ISIclimate change, ecosystems, forestry, geographic information systems, land use, land use and land cover, mediterranean ecosystem, mediterranean region, population exposure, urban population, western mediterranean, wildfire, wildland urban interface, fires, gis, hazard assessment, land cover, land use, modis, risk assessment, satellite imagery, urban population, wildfire, article, chile, cropland, evergreen, forest, france, geographic information system, human, italy, nonhuman, population exposure, portugal, public policy, satellite imagery, savanna, season, spain, urban area, urban population, wildfire, chile, environmental protection, chile, chile, conservation of natural resources, wildfires
Spiky fluctuations and scaling in high-resolution EPICA ice core dust fluxesLovejoy, Shaun; Lambert, FabriceCiudades Resilientes2019.010.5194/cp-15-1999-2019Abstract. 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.Climate of the Past1814-9332 Reuters ISIdust, extreme event, flux measurement, glaciation, hydrological cycle, ice core, interglacial, last glacial maximum, paleoclimate, resolution, scale effect, time series analysis, antarctica, dome concordia, east antarctica
The Anthropocene in ChileBauer, C.; Correa, C.; Gallardo, L.; González, G.; Guridi, R.; Latorre, C.; Pommier, E.; Riffo, S.; Saavedra, B.; Simonetti, C.; Tironi, M.Ciudades Resilientes2019.010.1215/22011919-7754578Environmental Humanities2201-1919, 2201-1919 Reuters ISIA
La compleja definición del problema socioambiental: racionalidades y controversiasMorales, Bárbara; Aliste, Enrique; Neira, C Ignacio; Urquiza, AnahíCiudades Resilientes2019.010.5354/0719-0527.2019.54834Drawing 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.Revista Mad0718-052743-5140.0Thomson Reuters ISIchile, complexity, development, socio-environmental problems, sustainability
In and out of glacial extremes by way of dust−climate feedbacksShaffer, Gary; Lambert, FabriceCiudades Resilientes2018.010.1073/pnas.1708174115Mineral 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.Proceedings of the National Academy of Sciences0027-8424 Reuters ISIcarbon dioxide, ice, atmospheric deposition, climate, cold, concentration (parameters), conference paper, controlled study, dust, dust radiative forcing, environmental parameters, glacial maxima, glacial period, glaciation, interglacial, iron fertilization forcing, land use, priority journal, sea, sediment, simulation, temperature, time series analysis
Onset and Evolution of Southern Annular Mode-Like Changes at Centennial TimescaleMoreno, P. I.; Vilanova, I.; Villa-Martínez, R.; Dunbar, R. B.; Mucciarone, D. A.; Kaplan, M. R.; Garreaud, R. D.; Rojas, M.; Moy, C. M.; De Pol-Holz, R.; Lambert, F.Cambio de Uso de Suelo; Ciudades Resilientes; Agua y Extremos; Gobernanza e Interfaz Ciencia y Política2018.010.1038/s41598-018-21836-6The 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.Scientific Reports2045-2322 Reuters ISIantarctica, article, climate change, cold stress, glaciation, holocene, lake sediment, latitude, southern hemisphere, tropic climate, writing
Spatial and temporal disaggregation of the on-road vehicle emission inventory in a medium-sized Andean city. Comparison of GIS-based top-down methodologiesGómez, C.D.; González, C.M.; Osses, M.; Aristizábal, B.H.Ciudades Resilientes2018.010.1016/j.atmosenv.2018.01.049Emission 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.Atmospheric Environment1352-2310 Reuters ISIair quality, decision making, geographic information systems, housing, information management, particles (particulate matter), pollution, roads and streets, spatial distribution, traffic control, urban transportation, vehicles, emission inventories, medium-sized cities, on-road vehicle emissions, public policy decisions, spatial and temporal distribution, spatial disaggregation, top-down methods, vehicular emission, air pollution, air quality, atmospheric modeling, comparative study, emission inventory, gis, pollutant source, public transport, spatiotemporal analysis, top-down approach, traffic emission, urban pollution, air quality, article, car driving, colombia, geographic information system, industrial area, motorcycle, particulate matter, priority journal, traffic, andes, caldas, colombia, manizales, south america
Indoor PM2.5 in an urban zone with heavy wood smoke pollution: The case of Temuco, ChileJorquera, Hector; Barraza, Francisco; Heyer, Johanna; Valdivia, Gonzalo S.; Schiappacasse, Luis Nicolás; Montoya, Lupita D.Ciudades Resilientes2018.010.1016/j.envpol.2018.01.085Temuco 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.Environmental Pollution0269-7491 Reuters ISIbuilding codes, heating, indoor air pollution, smoke, software testing, urban growth, wood, elemental compositions, indoor air quality, infiltration factor, infiltration parameters, pm2.5 concentration, statistical evaluation, sustainable urban development, woodstove, air quality, arsenic, bromine, calcium, iron, rubidium, silicon, sulfur, titanium, air quality, cooking appliance, indoor air, infiltration, mass balance, particulate matter, smoke, sustainable development, urban atmosphere, wood, adult, air quality control, air sampling, ambient air, article, chemical composition, chile, circadian rhythm, cohort analysis, combustion, concentration (parameters), controlled study, cooking, environmental exposure, heating, household, human, indoor air pollution, night, particulate matter, smoke, urban area, winter, wood, air pollutant, air pollution, analysis, city, cooking, environmental monitoring, indoor air pollution, particulate matter, season, statistics and numerical data, araucania, chile, temuco, air pollutants, air pollution, air pollution, indoor, chile, cities, cooking, environmental monitoring, heating, humans, particulate matter, seasons, wood
ENSO Influence on Coastal Fog-Water Yield in the Atacama Desert, Chiledel Río, Camilo; Rivera, Daniela; Siegmund, Alexander; Wolf, Nils; Cereceda, Pilar; Larraín, Horacio; Lobos, Felipe; Garcia, Juan-Luis; Osses, Pablo; Zanetta, Nicolás; Lambert, FabriceCiudades Resilientes2018.010.4209/aaqr.2017.01.0022Fog 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.Aerosol and Air Quality Research1680-8584 Reuters ISIatmospheric pressure, climatology, clouds, fog, nickel, oceanography, scandium, surface waters, water, atacama, fog water, southeast pacific (sep), southern oscillation, stratocumulus clouds, water resources, annual cycle, arid environment, cloud cover, correlation, el nino-southern oscillation, fog, satellite imagery, spatial variation, stratocumulus, sustainability, water resource, atacama desert, chile, coastal cordillera
VEIN v0.2.2: an R package for bottom–up vehicular emissions inventoriesIbarra-Espinosa, Sergio; Ynoue, Rita; O&apos;Sullivan, Shane; Pebesma, Edzer; Andrade, María de Fátima; Osses, MauricioCiudades Resilientes2018.010.5194/gmd-11-2209-2018. 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.Geoscientific Model Development1991-9603 Reuters ISIdeveloping world, emission inventory, environmental protection, pollutant source, road transport, traffic emission, urban planning, brazil, united states
Megafires in Chile 2017: Monitoring multiscale environmental impacts of burned ecosystemsde la Barrera, Francisco; Barraza, Francisco; Favier, Philomène; Ruiz, Vannia; Quense, JorgeCiudades Resilientes2018.010.1016/j.scitotenv.2018.05.119During 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.Science of The Total Environment0048-9697 Reuters ISIair pollution, air quality, damage detection, fires, floods, forestry, hazards, landslides, particles (particulate matter), remote sensing, risk assessment, digital elevation model, ecosystem services, impact of wildfires, multi criteria analysis, natural hazard, particulate matter, remote sensing analysis, spearman correlation, ecosystems, air quality, atmospheric pollution, ecosystem service, environmental impact assessment, environmental monitoring, geographical variation, remote sensing, risk assessment, wildfire, air pollution, air quality, article, atmospheric dispersion, chile, city, ecosystem health, environmental impact assessment, environmental monitoring, flooding, forest, hazard assessment, land drainage, landslide, particle size, particulate matter, priority journal, remote sensing, scrub, sediment, spatial analysis, urban area, water flow, wildfire, chile
Evolution of air quality in Santiago: The role of mobility and lessons from the science-policy interfaceGallardo, Laura; Barraza, Francisco; Ceballos, Andrés; Galleguillos, Mauricio; Huneeus, Nicolás; Lambert, Fabrice; Ibarra, Cecilia; Munizaga, Marcela; O'Ryan, Raúl; Osses, Mauricio; Tolvett, Sebastián; Urquiza, Anahí; Véliz, Karina D.Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política2018.010.1525/elementa.293Worldwide, 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.Elem Sci Anth2325-1026 Reuters ISIaerosol, air quality, anthropocene, atmospheric pollution, capital city, climate change, developing world, energy efficiency, global change, greenhouse gas, mobility, particulate matter, policy making, pollution control, urban development, urban population, urban sprawl, urbanization, chile, latin america
The PMIP4 contribution to CMIP6 – Part 1: Overview and over-arching analysis planKageyama, Masa; Braconnot, Pascale; Harrison, Sandy P.; Haywood, Alan M.; Jungclaus, Johann H.; Otto-Bliesner, Bette L.; Peterschmitt, Jean-Yves; Abe-Ouchi, Ayako; Albani, Samuel; Bartlein, Patrick J.; Brierley, Chris; Crucifix, Michel; Dolan, Aisling; Fernandez-Donado, Laura; Fischer, Hubertus; Hopcroft, Peter O.; Ivanovic, Ruza F.; Lambert, Fabrice; Lunt, Daniel J.; Mahowald, Natalie M.; Peltier, W. Richard; Phipps, Steven J.; Roche, Didier M.; Schmidt, Gavin A.; Tarasov, Lev; Valdes, Paul J.; Zhang, Qiong; Zhou, TianjunCiudades Resilientes2018.010.5194/gmd-11-1033-2018This 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.Geoscientific Model Development1991-9603 Reuters ISIclimate change, climate forcing, climate prediction, climate variation, cmip, environmental impact, holocene, last glacial maximum, last interglacial, paleoclimate, paleoenvironment, pliocene
δ 18 O of Fissurella maxima as a proxy for reconstructing Early Holocene sea surface temperatures in the coastal Atacama desert (25°S)Flores, Carola; Gayo, Eugenia M.; Salazar, Diego; Broitman, Bernardo R.Ciudades Resilientes2018.010.1016/j.palaeo.2018.03.031Fissurella 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.Palaeogeography, Palaeoclimatology, Palaeoecology0031-0182 Reuters ISIarchaeological evidence, calibration, carbonate, coastal zone, gastropod, holocene, in situ measurement, midden, oxygen isotope, paleoceanography, paleotemperature, proxy climate record, reconstruction, sea surface temperature, shell, stable isotope, thermometry, atacama desert, chile, humboldt current, pacific coast [chile], pacific coast [south america], pacific ocean, pacific ocean (southeast), fissurella maxima, mollusca
Local and remote black carbon sources in the Metropolitan Area of Buenos AiresDiaz Resquin, Melisa; Santágata, Daniela; Gallardo, Laura; Gómez, Darío; Rössler, Cristina; Dawidowski, LauraCiudades Resilientes2018.010.1016/j.atmosenv.2018.03.018Equivalent 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.Atmospheric Environment1352-2310 Reuters ISIaerosols, biomass, boundary layers, carbon, charcoal, atmospheric conditions, biomass-burning, black carbon, carbonaceous components, fossil fuel combustion, fossil fuel emissions, megacities, relative contribution, fossil fuels, black carbon, equivalent black carbon, fossil fuel, unclassified drug, aerosol, anthropogenic source, biomass burning, black carbon, boundary layer, concentration (composition), diurnal variation, fossil fuel, long range transport, metropolitan area, particle size, pollutant transport, seasonal variation, wavelength, aerosol, agriculture, airborne particle, argentina, article, atmospheric transport, attenuation, autumn, biomass burning, boundary layer, carbon source, circadian rhythm, combustion, concentration (parameters), exhaust gas, fire and fire related phenomena, forestry, heating, light, mass, particulate matter, priority journal, satellite imagery, seasonal variation, spatiotemporal analysis, spring, suburban area, summer, traffic, winter, wood, argentina, buenos aires [argentina]
New insights into the use of stable water isotopes at the northern Antarctic Peninsula as a tool for regional climate studiesFernandoy, Francisco; Tetzner, Dieter; Meyer, Hanno; Gacitúa, Guisella; Hoffmann, Kirstin; Falk, Ulrike; Lambert, Fabrice; MacDonell, ShelleyCiudades Resilientes2018.010.5194/tc-12-1069-2018Due 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.The Cryosphere1994-0424 Reuters ISIaccumulation rate, climate modeling, climate signal, data set, deuterium, ice cover, meteorology, regional climate, sea ice, stable isotope, surface temperature, topography, troposphere, warming, antarctic peninsula, antarctica, west antarctica
Climate change governance in the Anthropocene: Emergence of Polycentrism in ChileArriagada, Rodrigo Antonio; Aldunce, Paulina; Blanco, Gustavo; Ibarra, Cecilia; Moraga, Pilar; Nahuelhual, Laura; O'Ryan, Raul; Urquiza, Anahí; Gallardo, LauraCiudades Resilientes; Gobernanza e Interfaz Ciencia y Política2018.010.1525/elementa.329Multilateral 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.Elem Sci Anth2325-1026 Reuters ISIaction plan, adaptive management, anthropocene, climate change, conceptual framework, decision making, environmental policy, financial system, governance approach, mitigation, strategic approach, chile
Metalogue as a transdisciplinary collaboration toolUrquiza, A.; Amigo, C.; Billi, M.; Brandao, G.; Morales, B.Ciudades Resilientes2018.010.4067/S0717-554X2018000200182Contemporary 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.Cinta moebio0717-554X182-19862Thomson Reuters ISIconstructivist, contextual intervention, interface, policy, reflexivity, science, transdiscipline
Synchronization of energy consumption by human societies throughout the HoloceneFreeman, Jacob; Baggio, Jacopo A.; Robinson, Erick; Byers, David A.; Gayo, Eugenia; Finley, Judson Byrd; Meyer, Jack A.; Kelly, Robert L.; Anderies, John M.Ciudades Resilientes2018.010.1073/pnas.1802859115We 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.Proceedings of the National Academy of Sciences0027-8424 Reuters ISIarticle, bioenergy, biomass conversion, controlled study, cultural anthropology, environmental change, environmental sustainability, evolution, holocene, nonhuman, politics, population research, priority journal, social aspect, socioeconomics, archeology, ecosystem, history, human, social change, sociology, fossil fuel, archaeology, ecosystem, fossil fuels, history, ancient, humans, social change, socioeconomic factors, sociology
Ambient PM10 impacts brought by the extreme flooding event of March 24–26, 2015, in Copiapó, ChileJorquera, Héctor; Villalobos, Ana María; Barraza, FranciscoCiudades Resilientes2018.010.1007/s11869-018-0549-5On 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.Air Quality, Atmosphere & Health1873-9318 Reuters ISIambient air, dust, extreme event, flooding, particulate matter, pollution effect, smelting, source apportionment, suspended particulate matter, sustainable development, urban development, atacama, atacama desert, chile, copiapo
Chronology, stratigraphy and hydrological modelling of extensive wetlands and paleolakes in the hyperarid core of the Atacama Desert during the late quaternaryPfeiffer, Marco; Latorre, Claudio; Santoro, Calogero M.; Gayo, Eugenia M.; Rojas, Rodrigo; Carrevedo, María Laura; McRostie, Virginia B.; Finstad, Kari M.; Heimsath, Arjun; Jungers, Matthew C.; De Pol-Holz, Ricardo; Amundson, RonaldCambio de Uso de Suelo; Ciudades Resilientes2018.010.1016/j.quascirev.2018.08.001The 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.Quaternary Science Reviews0277-3791 Reuters ISIarid regions, hydrology, sedimentology, sodium chloride, stratigraphy, water resources, atacama desert, hyperaridity, late quaternary, paleogeography, south america, wetlands, arid region, aridity, chronology, gastropod, hydrological modeling, lake, paleoclimate, paleogeography, pleistocene, recharge, salt pan, sedimentology, stratigraphy, wetland, andes, atacama desert, chile, chile, bacillariophyta, gastropoda
ACTA DE TARAPACÁ: “PUEBLO SIN AGUA, PUEBLO MUERTO”Santoro, Calogero M.; Castro, Victoria; Capriles, José M.; Barraza, José; Correa, Jacqueline; Marquet, Pablo A.; McRostie, Virginia; Gayo, Eugenia M.; Latorre, Claudio; Valenzuela, Daniela; Uribe, Mauricio; de Porras, Maria Eugenia; Standen, Vivien G.; Angelo, Dante; Maldonado, Antonio; Hamamé, Eva; Jofré, DaniellaCiudades Resilientes2018.010.4067/S0717-73562018000200169“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.Chungará (Arica)0717-7356 Reuters ISI
Status and future of numerical atmospheric aerosol prediction with a focus on data requirementsBenedetti, Angela; Reid, Jeffrey S.; Knippertz, Peter; Marsham, John H.; Di Giuseppe, Francesca; Rémy, Samuel; Basart, Sara; Boucher, Olivier; Brooks, Ian M.; Menut, Laurent; Mona, Lucia; Laj, Paolo; Pappalardo, Gelsomina; Wiedensohler, Alfred; Baklanov, Alexander; Brooks, Malcolm; Colarco, Peter R.; Cuevas, Emilio; da Silva, Arlindo; Escribano, Jeronimo; Flemming, Johannes; Huneeus, Nicolas; Jorba, Oriol; Kazadzis, Stelios; Kinne, Stefan; Popp, Thomas; Quinn, Patricia K.; Sekiyama, Thomas T.; Tanaka, Taichu; Terradellas, EnricCiudades Resilientes2018.010.5194/acp-18-10615-2018Numerical 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.Atmospheric Chemistry and Physics1680-7324 Reuters ISIaerosol, aerosol formation, concentration (composition), data assimilation, numerical model, particle size, prediction
Impact of residential combustion and transport emissions on air pollution in Santiago during winterMazzeo, Andrea; Huneeus, Nicolás; Ordoñez, César; Orfanoz-Cheuquelaf, Andrea; Menut, Laurent; Mailler, Sylvan; Valari, Myrto; Denier van der Gon, Hugo; Gallardo, Laura; Muñoz, Ricardo; Donoso, Rodrigo; Galleguillos, Maurico; Osses, Mauricio; Tolvett, SebastianCambio de Uso de Suelo; Ciudades Resilientes2018.010.1016/j.atmosenv.2018.06.043Santiago (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.Atmospheric Environment1352-2310 Reuters ISIair quality, combustion, dust, housing, nitrogen oxides, roads and streets, sensitivity analysis, chemistry transport model, meteorological measurements, meteorological modeling, mitigation policies, on-road emissions, pm2.5, residential emissions, road transport emissions, atmospheric movements, nitrogen oxide, air quality, atmospheric modeling, atmospheric pollution, climate modeling, combustion, environmental factor, extreme event, mitigation, nitrogen oxides, particulate matter, pollutant source, pollutant transport, pollution effect, pollution monitoring, pollution policy, public health, residential location, road traffic, spatial distribution, traffic emission, winter, air pollution, airborne particle, article, chile, combustion, concentration (parameters), exhaust gas, meteorology, model, particle size, priority journal, residential area, surface property, traffic and transport, winter, chile, metropolitana
Participatory Energy Transitions as Boundary Objects: The Case of Chile's Energía2050Urquiza, Anahí; Amigo, Catalina; Billi, Marco; Espinosa, PatricioCiudades Resilientes2018.010.3389/fenrg.2018.00134This 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.Frontiers in Energy Research2296-598X Reuters ISIenergy policy, boundary objects, chile, deliberative democracy, energy transitions, polycentric governance, public participation, public policy
Water markets and social–ecological resilience to water stress in the context of climate change: an analysis of the Limarí Basin, ChileUrquiza, Anahí; Billi, MarcoCiudades Resilientes2018.010.1007/s10668-018-0271-3The 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.Environment, Development and Sustainability1387-585X, 1573-2975 Reuters ISIbottom-up approach, climate change, empirical analysis, environmental conditions, governance approach, innovation, qualitative analysis, self organization, territorial planning, top-down approach, water industry, water management, water planning, water stress, chile
Andean caravan ceremonialism in the lowlands of the Atacama Desert: The Cruces de Molinos archaeological site, northern ChileValenzuela, Daniela; Cartajena, Isabel; Santoro, Calogero M.; Castro, Victoria; Gayo, Eugenia M.Ciudades Resilientes2018.010.1016/j.quaint.2018.09.016Camelid 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.Quaternary International10406182 Reuters ISIarchaeological evidence, iconography, mammal, rock art, settlement history, spatiotemporal analysis, atacama desert, chile, camelidae, lama (mammal)
Temporal evolution of main ambient PM2. 5 sources in Santiago, Chile, from 1998 to 2012Barraza, Francisco; Lambert, Fabrice; Jorquera, Héctor; Villalobos, Ana María; Gallardo, LauraCiudades Resilientes2017.010.5194/acp-17-10093-2017The 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 standardsAtmospheric Chemistry and Physics1680-7324 Reuters ISI
The pre-Columbian introduction and dispersal of Algarrobo (Prosopis, Section Algarobia) in the Atacama Desert of northern ChileMcRostie, Virginia B.; Gayo, Eugenia M.; Santoro, Calogero M.; De Pol-Holz, Ricardo; Latorre, ClaudioCambio de Uso de Suelo; Ciudades Resilientes2017.010.1371/journal.pone.0181759Archaeological 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.PLOS ONE1932-6203 Reuters ISIcarbon 14, article, chile, chronology, desert, holocene, leaf litter, nonhuman, paleoecology, phylogeny, plant dispersal, prosopis, species introduction, taxonomy, agriculture, archeology, classification, crop, desert climate, genetics, history, human, phylogeny, physiology, prosopis, agriculture, archaeology, chile, crops, agricultural, desert climate, history, ancient, humans, phylogeny, plant dispersal, prosopis
The PMIP4 contribution to CMIP6 – Part 4: Scientific objectives and experimental design of the PMIP4-CMIP6 Last Glacial Maximum experiments and PMIP4 sensitivity experimentsKageyama, Masa; Albani, Samuel; Braconnot, Pascale; Harrison, Sandy P.; Hopcroft, Peter O.; Ivanovic, Ruza F.; Lambert, Fabrice; Marti, Olivier; Peltier, W. Richard; Peterschmitt, Jean-Yves; Roche, Didier M.; Tarasov, Lev; Zhang, Xu; Brady, Esther C.; Haywood, Alan M.; LeGrande, Allegra N.; Lunt, Daniel J.; Mahowald, Natalie M.; Mikolajewicz, Uwe; Nisancioglu, Kerim H.; Otto-Bliesner, Bette L.; Renssen, Hans; Tomas, Robert A.; Zhang, Qiong; Abe-Ouchi, Ayako; Bartlein, Patrick J.; Cao, Jian; Li, Qiang; Lohmann, Gerrit; Ohgaito, Rumi; Shi, Xiaoxu; Volodin, Evgeny; Yoshida, Kohei; Zhang, Xiao; Zheng, WeipengCiudades Resilientes2017.010.5194/gmd-10-4035-2017The 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.Geoscientific Model Development1991-9603 Reuters ISIaerosol, climate modeling, cmip, experimental design, greenhouse gas, land surface, last glacial maximum, paleoclimate, reconstruction, relative abundance
Loco or no Loco? Holocene Climatic Fluctuations, Human Demography, and Community Based Management of Coastal Resources in Northern ChileSantoro, Calogero M.; Gayo, Eugenia M.; Carter, Chris; Standen, Vivien G.; Castro, Victoria; Valenzuela, Daniela; De Pol-Holz, Ricardo; Marquet, Pablo A.; Latorre, ClaudioCambio de Uso de Suelo; Ciudades Resilientes2017.010.3389/feart.2017.00077The 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.Frontiers in Earth Science2296-6463 Reuters ISIarid regions, climatology, demography, landforms, population dynamics, population statistics, shellfish, atacama desert, community-based management, cultural resources, demographic fluctuations, enso, holocene climate, socio-cultural patterns, technological innovation, probability distributions
The effect of climate change on electricity expenditures in MassachusettsVéliz, Karina D.; Kaufmann, Robert K.; Cleveland, Cutler J.; Stoner, Anne M.K.Ciudades Resilientes2017.010.1016/j.enpol.2017.03.016Climate 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.Energy Policy0301-4215 Reuters ISIcosts, electric power utilization, adaptation, annual expenditure, commercial customers, consumer expenditure, electricity expenditures, electricity prices, electricity-consumption, global-mean temperature, climate change, climate change, climate effect, electricity generation, electricity supply, energy use, price determination, massachusetts, united states
Comunicación ambiental y proyectos energéticos renovables no convencionales. Análisis de contenido en medios de comunicación de masa chilenosBilli, M; Urquiza Gómez, A; Feres Klenner, CCiudades Resilientes2017.010.4185/RLCS-2017-1216Se observa la tematización mediática de proyectos Energéticos Renovables No Convencionales [ERNC] en términos de la relevancia y tratamiento otorgados a distintas fuentes y estructuras temáticas emergentes. Metodología. Análisis de contenido con enfoque mixto sobre una muestra de 100 artículos de prensa digital chilena relacionados con ERNC, usando el marco analítico de la Teoría de Sistemas Sociales de Niklas Luhmann. Resultados y Discusión. La primacía de fuentes solares y eólicas se acompaña a una reducida claridad terminológica, que sin embargo permite construir estructuras temáticas distintas en relación con sistemas sociales como economía, ciencia, política y derecho. Las referencias medioambientales son más escasas y menos profundas, privilegiando sus aspectos evocativos y con máxima capacidad de enlace. Conclusiones. En lugar que observar a los medios como mera transmisión de racionalidades externas a ellos debería prestarse atención a su capacidad de crear realidad y representar el entorno social y medioambiental.Revista Latina de Comunicación Social1138-5820 Reuters ISIchile, climate change mitigation, energy crisis, environmental communication, mass media, non-conventional renewable energies
Aplicar una distinción. Un programa sistémico-constructivista para la investigación social cualitativaUrquiza, Anahi; Billi, Marco; Leal, TomasCiudades Resilientes2017.010.5354/0719-0527.2017.47269Por 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 praxisde 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, porun 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 paperofrece un modelo generalpara 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.Revista Mad0718-0527 Reuters ISIA
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 ecosystemsdel Río, Camilo; Lobos-Roco, Felipe; Latorre, Claudio; Koch, Marcus A.; García, Juan-Luis; Osses, Pablo; Lambert, Fabrice; Alfaro, Fernando; Siegmund, AlexanderCiudades Resilientes; Transversal2021.010.1007/s00606-021-01782-zAbstract 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.Plant Systematics and Evolution0378-2697, 1615-6110 Reuters ISIchile, enso, fog ecosystems, goes, interdecadal pacific oscillation, southeast pacific ocean
Anthropogenic Perturbations to the Atmospheric Molybdenum CycleWong, Michelle Y.; Rathod, Sagar D.; Marino, Roxanne; Li, Longlei; Howarth, Robert W.; Alastuey, Andres; Alaimo, Maria Grazia; Barraza, Francisco; Carneiro, Manuel Castro; Chellam, Shankararaman; Chen, Yu‐Cheng; Cohen, David D.; Connelly, David; Dongarra, Gaetano; Gómez, Darió; Hand, Jenny; Harrison, R. M.; Hopke, Philip K.; Hueglin, Christoph; Kuang, Yuan‐wen; Lambert, Fabrice; Liang, James; Losno, Remi; Maenhaut, Willy; Milando, Chad; Monteiro, Maria Inês Couto; Morera‐Gómez, Yasser; Querol, Xavier; Rodríguez, Sergio; Smichowski, Patricia; Varrica, Daniela; Xiao, Yi‐hua; Xu, Yangjunjie; Mahowald, Natalie M.Ciudades Resilientes2021.010.1029/2020GB006787Molybdenum (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.Global Biogeochemical Cycles0886-6236, 1944-9224 Reuters ISIconcentration (composition), ecosystem function, estimation method, human activity, mass balance, molybdenum, nitrate, nitrogen, nitrogen fixation
Past abrupt changes, tipping points and cascading impacts in the Earth systemBrovkin, Victor; Brook, Edward; Williams, John W.; Bathiany, Sebastian; Lenton, Timothy M.; Barton, Michael; DeConto, Robert M.; Donges, Jonathan F.; Ganopolski, Andrey; McManus, Jerry; Praetorius, Summer; de Vernal, Anne; Abe-Ouchi, Ayako; Cheng, Hai; Claussen, Martin; Crucifix, Michel; Gallopín, Gilberto; Iglesias, Virginia; Kaufman, Darrell S.; Kleinen, Thomas; Lambert, Fabrice; van der Leeuw, Sander; Liddy, Hannah; Loutre, Marie-France; McGee, David; Rehfeld, Kira; Rhodes, Rachael; Seddon, Alistair W. R.; Trauth, Martin H.; Vanderveken, Lilian; Yu, ZichengCiudades Resilientes2021.010.1038/s41561-021-00790-5The 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.Nature Geoscience1752-0894, 1752-0908 Reuters ISI
Energy poverty effects on policy-based PM2.5 emissions mitigation in southern and central ChileCalvo, Rubén; Álamos, Nicolás; Huneeus, Nicolás; O'Ryan, RaúlCiudades Resilientes2022.010.1016/j.enpol.2021.112762Residential 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.Energy Policy03014215 Reuters ISIenergy poverty, firewood consumption, particulate matter, stove replacement, thermal retrofit
A distributed resistance inverse method for flow obstacle identification from internal velocity measurementsAguayo, Jorge; Bertoglio, Cristóbal; Osses, AxelCiudades Resilientes2021.010.1088/1361-6420/abced8Abstract 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.Inverse Problems0266-5611, 1361-6420 Reuters ISIflow of fluids, magnetic resonance imaging, numerical methods, cost functionals, differentiability, distributed resistance, first and second order optimality conditions, incompressible fluid flow, inverse methods, numerical experiments, parameter methods, inverse problems
A simplified homogenization model applied to viscoelastic behavior of cortical bone at ultrasonic frequenciesAróstica, Reidmen; Aguilera, Ana; Osses, Axel; Minonzio, Jean-GabrielCiudades Resilientes2022.010.1016/j.jbiomech.2021.110868Journal of Biomechanics00219290 Reuters ISIbone, inverse problems, tensors, ultrasonic waves, viscoelasticity, attenuation, cell problems, cortical bone, homogenization theory, microstructure mechanic, multiscale, quality factors, simplified homogenizations, ultrasonic frequency, viscoelastic behaviors, microstructure, article, cortical bone, porosity, ultrasound, viscoelasticity
Climate change perception, vulnerability, and readiness: inter-country variability and emerging patterns in Latin AmericaAzócar, Gabriela; Billi, Marco; Calvo, Rubén; Huneeus, Nicolas; Lagos, Marta; Sapiains, Rodolfo; Urquiza, AnahíCiudades Resilientes2021.010.1007/s13412-020-00639-0Journal of Environmental Studies and Sciences2190-6483, 2190-6491 Reuters ISIadaptive management, climate change, perception, questionnaire survey, vulnerability, latin america
Urban Heat Islands and Vulnerable Populations in a Mid-Size Coastal City in an Arid EnvironmentQuintana-Talvac, Carolina; Corvacho-Ganahin, Oscar; Smith, Pamela; Sarricolea, Pablo; Prieto, Manuel; Meseguer-Ruiz, OliverCiudades Resilientes2021.010.3390/atmos12070917Arica 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.Atmosphere2073-4433 Reuters ISImorphology, satellite imagery, arid environments, landsat satellite images, new constructions, population census, surface temperatures, surface urban heat islands, urban heat island, urban morphology, atmospheric temperature, arid environment, desert, heat island, landsat, social segregation, socioeconomic status, surface temperature, vulnerability, arica, arica and parinacota, chile, atacama
Economic evaluation of fuel cell-powered OFF-ROAD machinery using stochastic analysisReyes-Valenzuela, Mauricio; Sánchez-Squella, Antonio; Barraza, Rodrigo; Osses, Mauricio; Valdivia-Lefort, PatricioCiudades Resilientes2021.010.1016/j.ijhydene.2021.10.247This study proposes a business model to obtain a successful off-road machinery retrofit using fuel cell technology by the means of evaluating scenarios using the net present value NPV of the project as a figure of merit. Given the uncertainty of some parameters, such as the price of diesel, cost of hydrogen, and cost of technology. It is proposed to carry out a Monte Carlo simulation to sensitize the business model. The results of the simulation declare that the possibility of achieving a positive NPV is increased from 54% considering present conditions to 99% considering projections for the year 2030. The prices of diesel and hydrogen condition the results in a more relevant manner and a price relationship is obtained between these two variables. Taxes could play a key role in the future, according to the results obtained in this study.International Journal of Hydrogen Energy03603199 Reuters ISIcosts, diesel engines, fuel cells, hydrogen, intelligent systems, retrofitting, roads and streets, stochastic systems, business models, condition, economics evaluations, electromobility, fuel cell technologies, monte carlo's simulation, off-road machinery, sensitisation, stochastic analysis, the net present value (npv), monte carlo methods
Chemical Signals in Tree Rings from Northern Patagonia as Indicators of Calbuco Volcano Eruptions since the 16th CenturyBertin, Lizette J.; Christie, Duncan A.; Sheppard, Paul R.; Muñoz, Ariel A.; Lara, Antonio; Alvarez, ClaudioCambio de Uso de Suelo; Ciudades Resilientes; Agua y Extremos2021.010.3390/f12101305The 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.Forests1999-4907 Reuters ISIforestry, indicators (chemical), inductively coupled plasma, mass spectrometry, chemical signals, fitzroya cupressoides, inductively coupled plasma-mass spectrometry, northern patagonia, risk classification, sub-plinian eruption, tree rings, volcanic eruptions, volcanic explosivity indices, volcano eruptions, volcanoes, chemical analysis, dendrochronology, inductively coupled plasma method, pine, plinian eruption, sixteenth century, territorial planning, tree ring, chemicals, forestry, frequency, patagonia, records, resolution, rings, trees, argentina, chile, patagonia, fitzroya cupressoides