Línea de investigación:

Ciudades resilientes

Según Naciones Unidas, aunque las ciudades cubrieron menos del 2% de la superficie terrestre en 2011, consumieron casi el 80% de la energía mundial y produjeron más del 60% de todo el dióxido de carbono. Esto es relevante para Chile, donde casi el 90% de la población se considera urbana y aproximadamente la mitad de la habitantes se concentra en solo tres áreas metropolitanas: Santiago, Valparaíso y Concepción.

Varias ciudades del país experimentan una mala calidad de aire asociada a la combustión residencial y el transporte. Ante ello, el gobierno chileno incluyó planes de descontaminación y un impuesto al diésel en la Contribución Nacionalmente Determinada (NDC, por sus siglas en inglés) para el Acuerdo de París. Además, nuestras ciudades son altamente vulnerables a los efectos del cambio climático, como inundaciones, sequías, olas de calor y problemas de salud. Estas amenazas se ven agravadas por la desigualdad social y la segregación urbana.

El (CR)2 ha desarrollado e implementado modelos, inventarios de emisiones y otras herramientas, además de diagnósticos y análisis integrales de temas urbanos. Sin embargo, es necesario comprender mejor las dinámicas entre la energía, el uso del suelo, las emisiones, la demografía, la gobernanza y los procesos sociales y biofísicos.

Para ello, el equipo de investigación examinará los impactos urbanos en diferentes escalas de tiempo: desde registros paleoclimáticos de los primeros asentamientos humanos en Chile hasta proyecciones de posibles condiciones para las ciudades en escenarios climáticos futuros.

El área de ciencias sociales de nuestro grupo trabajará para comprender cómo la sociedad, desde las comunidades locales a las autoridades nacionales, se está adaptando a los cambios en eventos extremos, a través de la investigación centrada en las prácticas actuales, su utilidad, las barreras para la implementación y las oportunidades de mejora.

INVESTIGADORA PRINCIPAL

CO-INVESTIGADORA PRINCIPAL

INVESTIGADORES ASOCIADOS

INVESTIGADOR JORNADA COMPLETA

INVESTIGADORES ADJUNTOS

INVESTIGADOR POSTDOCTORAL

INVESTIGADORES COLABORADORES

ESTUDIANTES

Nombre Apellido
Benjamin Gomez
Camilo Menares
Catalina Amigo Jorquera
Claudio Neira
Damaris Arrieta
José Navea
Juliette Marín
Kevin Basoa Barraza
luis gomez
Marco Billi
María Catalina Muñoz Muñoz
María Catalinax Muñoz Muñoz
Matias Fleischmann
Matías Plass Carvallo
Melisa Diaz Resquin
Natalia Prieto Gavilán
Nicolás Alamos
Nicolás Pantoja
Rocío Ormazabal
Rubén Calvo
Santiago Parraguez
sebastian ruiz
Sebastian Ruiz Pereira
Valentina Barrera
Ximena Insunza
Constanza Urbina Guerra
Charlie Eduardo Opazo Collao
Macarena Ximena Salinas Camus
Lucas Eduardo Castillo Elmes
Gabriel Ignacio Lagos Duarte

Noticias relacionadas

Línea de InvestigaciónAñoAutoresTítuloRevistaFicha de PublicaciónDOIAbstractAccesoPáginasVolumenIndexKey Words
Ciudades Resilientes; Gobernanza e Interfaz Ciencia y Política2021Valencia, Felipe; Billi, Marco; Urquiza, AnahíOvercoming energy poverty through micro-grids: An integrated framework for resilient, participatory sociotechnical transitionsEnergy Research & Social Science10.1016/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.https://linkinghub.elsevier.com/retrieve/pii/S221462962100123710203075.0Thomson Reuters ISIchile, energy poverty, micro-grids, participatory co-construction, socio-ecological resilience, socio-technical transitions, sustainability
Ciudades Resilientes; Agua y Extremos2021Henríquez, Carla A.; Moreno, Patricio I.; Lambert, Fabrice; Alloway, Brent V.The role of climate and disturbance regimes upon temperate rainforests during the Holocene: A stratigraphic perspective from Lago Fonk (∼40°S), northwestern PatagoniaQuaternary Science Reviews10.1016/j.quascirev.2021.106890https://linkinghub.elsevier.com/retrieve/pii/S0277379121000974106890258.0Thomson 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
Ciudades Resilientes2021Toro 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.Air pollution and COVID-19 lockdown in a large South American city: Santiago Metropolitan Area, ChileUrban Climate10.1016/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.https://linkinghub.elsevier.com/retrieve/pii/S221209552100033X10080336.0Thomson Reuters ISIcovid-19 lockdown, traffic emission rates, urban air quality
Ciudades Resilientes; Agua y Extremos; Gobernanza e Interfaz Ciencia y Política2021Ancapichún, 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 PaulRadiocarbon bomb-peak signal in tree-rings from the tropical Andes register low latitude atmospheric dynamics in the Southern HemisphereScience of The Total Environment10.1016/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.https://linkinghub.elsevier.com/retrieve/pii/S0048969721001923145126774.0Thomson 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
Ciudades Resilientes2021Ruiz Pereira, S.; Marquardt, C.; Beriain, E.; Lambert, F.Permafrost evolution in a mountain catchment near Santiago de ChileJournal of South American Earth Sciences10.1016/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.https://linkinghub.elsevier.com/retrieve/pii/S0895981121001401103293109.0Thomson Reuters ISIaggradation, catchment, environmental degradation, mountain environment, permafrost, solar radiation, surface temperature, aconcagua, andes, argentina, chile, cordillera principal, metropolitana, santiago [metropolitana]
Ciudades Resilientes; Agua y Extremos2021Aldunce, Paulina; Lillo-Ortega, Gloria; Araya-Valenzuela, Dámare; Maldonado-Portilla, Pamela; Gallardo, LauraEvaluating adaptation to drought in a changing climate: experience at the local scale in the Aconcagua ValleyClimate and Development10.1080/17565529.2021.1893150Since 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.https://www.tandfonline.com/doi/full/10.1080/17565529.2021.18931501-12Thomson Reuters ISIchile, climate change, drought, evaluation of adaptation, index for the usefulness of adaptation practices (iupa)
Ciudades Resilientes2021Morawska, 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, CelineThe state of science on severe air pollution episodes: Quantitative and qualitative analysisEnvironment International10.1016/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.https://linkinghub.elsevier.com/retrieve/pii/S0160412021003573106732156.0Thomson 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
Ciudades Resilientes2021Menares, Camilo; Perez, Patricio; Parraguez, Santiago; Fleming, Zoë L.Forecasting PM2.5 levels in Santiago de Chile using deep learning neural networksUrban Climate10.1016/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.https://linkinghub.elsevier.com/retrieve/pii/S221209552100136X10090638.0Thomson Reuters ISIair quality forecasting, deep neural networks, fine particulate matter, lstm, machine learning, meteorology forecast
Ciudades Resilientes2021Valdés Salgado, Macarena; Smith, Pamela; Opazo, Mariel A.; Huneeus, NicolásLong-Term Exposure to Fine and Coarse Particulate Matter and COVID-19 Incidence and Mortality Rate in Chile during 2020International Journal of Environmental Research and Public Health10.3390/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.https://www.mdpi.com/1660-4601/18/14/7409740918.0Thomson 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
Ciudades Resilientes2021Jiménez-Uribe, Dámaris A.; Daniels, Darwin; Fleming, Zoë L.; Vélez-Pereira, Andrés M.Road Traffic Noise on the Santa Marta City Tourist RouteApplied Sciences10.3390/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).https://www.mdpi.com/2076-3417/11/16/7196719611.0Thomson Reuters ISIacoustic pollution, analysis of variance, field measurements, freeway, traffic flow dynamics
Ciudades Resilientes2021Da Venezia, Claudia; Hussein, Nayib; Hernández, Marcela; Contreras, Johanna; Morales, Alicia; Valdés, Macarena; Rojas, Francisca; Matamala, Loreto; Hernández-Ríos, PatriciaAssessment of Cardiovascular Risk in Women with Periodontal Diseases According to C-reactive Protein LevelsBiomolecules10.3390/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.https://www.mdpi.com/2218-273X/11/8/1238123811.0Thomson 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
Ciudades Resilientes2021Nolte, David; Urbina, Jesús; Sotelo, Julio; Sok, Leo; Montalba, Cristian; Valverde, Israel; Osses, Axel; Uribe, Sergio; Bertoglio, CristóbalValidation of 4D Flow based relative pressure maps in aortic flowsMedical Image Analysis10.1016/j.media.2021.102195While 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.https://linkinghub.elsevier.com/retrieve/pii/S136184152100240110219574.0Thomson 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
Ciudades Resilientes2021Cosentino, N. J.; Gaiero, D. M.; Lambert, F.Present‐Day Patagonian Dust Emissions: Combining Surface Visibility, Mass Flux, and Reanalysis DataJournal of Geophysical Research: Atmospheres10.1029/2020JD034459The 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.https://onlinelibrary.wiley.com/doi/10.1029/2020JD034459126.0Thomson Reuters ISIatmospheric pollution, long range transport, mass transfer, mineral dust, pollutant source, pollution monitoring, visibility, antarctica, patagonia, south america
Ciudades Resilientes2021Sokhi, 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, MiguelA global observational analysis to understand changes in air quality during exceptionally low anthropogenic emission conditionsEnvironment International10.1016/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.https://linkinghub.elsevier.com/retrieve/pii/S0160412021004438106818157.0Thomson 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
Ciudades Resilientes2021Freeman, 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, ClaudioLandscape Engineering Impacts the Long-Term Stability of Agricultural PopulationsHuman Ecology10.1007/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.https://link.springer.com/10.1007/s10745-021-00242-zThomson Reuters ISIhuman population ecology, intensification, population stability, radiocarbon, resilience
Ciudades Resilientes; Gobernanza2021Urquiza, A.; Amigo, C.; Billi, M.; Calvo, R.; Gallardo, L.; Neira, C. I.; Rojas, M.An Integrated Framework to Streamline Resilience in the Context of Urban Climate Risk AssessmentEarth's Future10.1029/2020EF001508Cities 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.https://onlinelibrary.wiley.com/doi/10.1029/2020EF0015089.0Thomson Reuters ISIclimate risk, ecosystem services, polycentric governance, socio-ecological systems, systems-of-systems, urban resilience