43 research outputs found

    Identifying future hotspots of fire danger in the tropics: climate fire predictions for 2050, 2075 and 2100

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    Recent bursts in the incidence of large wildfires worldwide have raised concerns about the influence that climate and humans may have on future fire activity. Climate strongly influences global wildfire activity, and recent wildfire surges may signal fire weather-induced pyrogeographic shifts. Fire weather seasons have lengthened across ca.3 0 million km2 (25 % of the Earth’s vegetated surface), resulting in an 19% increase in global mean fire weather season length, which would allow for a doubling of the global burnable area affected if these fire weather changes were coupled with ignition sources and available fuel, which are largely controlled by humans. Disagreement exists on the relative importance of climate versus human drivers in shaping global fire regimes, with a particular gap in the pantropical region where fire has had a long presence in savannas, montane grasslands and dry forest ecosystems, but it has had a much more recent, infrequent and unknown role in many moist forest ecosystems such as rainforests and cloud montane forests. Either climate or human induced, scenarios of future increases in burned area (fire danger) are needed to i) navigate fire danger reduction policies (e.g fire management that controls prevention, suppression and restoration), ii) to understand how to improve fire-resilient landscapes, iii) to reduce Greenhouse Gas emissions from fire, particularly in regions with carbon-dense fires, and iv) to support capacity building for effective fire management development and implementation. In this research we map pantropical future fire danger in 2050 (2025-2049), 2075 (2050-2074), 2100 (2075-2099). Fire danger is here understood as the probability of fire spreading over more extended areas under severe climatic conditions (precipitation, temperature and drought), under more extreme future conditions determined by the CMIP5 data. Because human decisions on the land are difficult to model and project in the future, we here focus on projecting climate-driven fire danger only

    Trends in tropical forest loss and the social value of emission reductions

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    Reducing global forest losses is essential to mitigate climate change and its associated social costs. Multiple market and non-market factors can enhance or reduce forest loss. Here, to understand the role of non-market factors (for example, policies, climate anomalies or conflicts), we can compare observed trends to a reference (expected) scenario that excludes non-market factors. We define an expected scenario by simulating land-use decisions solely driven by market prices, productivities and presumably plausible decision-making. The land-use allocation model considers economic profits and uncertainties as incentives for forest conversion. We compare reference forest losses in Brazil, the Democratic Republic of Congo and Indonesia (2000–2019) with observed forest losses and assign differences from non-market factors. Our results suggest that non-market factors temporarily lead to lower-than-expected forest losses summing to 11.1 million hectares, but also to phases with higher-than-expected forest losses of 11.3 million hectares. Phases with lower-than-expected forest losses occurred earlier than those with higher-than-expected forest losses. The damages avoided by delaying emissions that would otherwise have occurred represent a social value of US$61.6 billion (as of the year 2000). This result shows the economic importance of forest conservation efforts in the tropics, even if reduced forest loss might be temporary and reverse over time

    Trabajo en red, resiliencia comunitaria y acción educativa en contextos excluidos

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    La presente comunicación tiene como objetivo mostrar algunas evidencias y experiencias que corroboran que la acción socioeducativa y comunitaria en red es crucial para resistir y revertir la exclusión social que sufren ciertos barrios y zonas de nuestras ciudades que tradicionalmente han sido separadas, segregadas y marginadas (Secchi, 2015). En concreto partiremos de la realidad social y educativa de Asperones, un barrio que nació en la transición a finales de la década de los ochenta, debido a un Plan de Erradicación del Chabolismo en 1987 en Málaga, con la intención de acabar con algunas zonas de bolsas de pobreza de la ciudad. Ahora, treinta años después (García, 1993), la situación de exclusión social de las familias que conforman el barrio es evidente. Este trabajo pone de relieve algunos de los aportes generados por los educadores sociales, maestros, psicólogos y trabajadores sociales de la mesa de infancia del barrio marginado de los Asperones (Málaga), apoyados por resultados empíricos de la investigación titulada "Trabajo en red y Atención Socioeducativa para la promoción de la Resiliencia de la Infancia en Riesgo Social" Proyecto de Excelencia (SEJ 1366) de la Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía. De esta manera, metodológicamente existe una apuesta por conjugar la experiencia profesional y los aprendizajes generados por los educadores sociales y demás técnicos, con algunos de los datos empíricos de la investigación citada. Por lo tanto, se pretende establecer un diálogo entre los saberes profesionales y académicos, favoreciendo un enriquecimiento mutuo y el aporte de un conocimiento multidimensional de la realidad y de la propia educación social. Hasta este momento, las aportaciones de educadoras e investigadoras coinciden en señalar diversos avances que a nivel social y educativo se han producido en un contexto de fuerte exclusión social. Además, se resalta el trabajo en red que están llevando a cabo instituciones públicas, asociaciones y ONGs, que con su acción socioeducativa y comunitaria en red son cruciales para resistir y revertir la exclusión social que sufre este barrio, siendo una zona de Málaga que ha sido separada, segregada y marginada. A su vez, este trabajo en red favorece el desarrollo profesional de los educadores/as enriquecido por un proceso de investigación participativo. Con esta sinergia, donde se enriquecen la experiencia profesional y la investigadora, queremos mostrar el avance a nivel educativo que se está produciendo en el barrio, no solamente por el éxito escolar ante el aumento de vecinos que asisten y poseen título educativo, sino también por las transformaciones en las propias instituciones y agentes socioeducativos, así como en la generación de sinergias entre ellos. Así es, los resultados empíricos y las experiencias profesionales pondrán de relieve que el trabajo en red, más allá de mejorar el éxito educativo, genera transformaciones sociales, favorece el desarrollo profesional, provoca cambios estructurales e institucionales y promueve relaciones más democráticas que de uno u otro modo va contrarrestando las desigualdades y las situaciones de exclusión social.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Climate tipping point interactions and cascades: a review

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    Climate tipping elements are large-scale subsystems of the Earth that may transgress critical thresholds (tipping points) under ongoing global warming, with substantial impacts on the biosphere and human societies. Frequently studied examples of such tipping elements include the Greenland Ice Sheet, the Atlantic Meridional Overturning Circulation (AMOC), permafrost, monsoon systems, and the Amazon rainforest. While recent scientific efforts have improved our knowledge about individual tipping elements, the interactions between them are less well understood. Also, the potential of individual tipping events to induce additional tipping elsewhere or stabilize other tipping elements is largely unknown. Here, we map out the current state of the literature on the interactions between climate tipping elements and review the influences between them. To do so, we gathered evidence from model simulations, observations, and conceptual understanding, as well as examples of paleoclimate reconstructions where multi-component or spatially propagating transitions were potentially at play. While uncertainties are large, we find indications that many of the interactions between tipping elements are destabilizing. Therefore, we conclude that tipping elements should not only be studied in isolation, but also more emphasis has to be put on potential interactions. This means that tipping cascades cannot be ruled out on centennial to millennial timescales at global warming levels between 1.5 and 2.0 circle C or on shorter timescales if global warming surpassed 2.0 circle C. At these higher levels of global warming, tipping cascades may then include fast tipping elements such as the AMOC or the Amazon rainforest. To address crucial knowledge gaps in tipping element interactions, we propose four strategies combining observation-based approaches, Earth system modeling expertise, computational advances, and expert knowledge

    Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

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    Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

    Common, low-frequency, rare, and ultra-rare coding variants contribute to COVID-19 severity

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    The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive individuals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were converted into separate sets of Boolean features, depending on the absence or the presence of variants in each gene. An ensemble of LASSO logistic regression models was used to identify the most informative Boolean features with respect to the genetic bases of severity. The Boolean features selected by these logistic models were combined into an Integrated PolyGenic Score that offers a synthetic and interpretable index for describing the contribution of host genetics in COVID-19 severity, as demonstrated through testing in several independent cohorts. Selected features belong to ultra-rare, rare, low-frequency, and common variants, including those in linkage disequilibrium with known GWAS loci. Noteworthily, around one quarter of the selected genes are sex-specific. Pathway analysis of the selected genes associated with COVID-19 severity reflected the multi-organ nature of the disease. The proposed model might provide useful information for developing diagnostics and therapeutics, while also being able to guide bedside disease management. © 2021, The Author(s)

    Genetic mechanisms of critical illness in COVID-19.

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    Host-mediated lung inflammation is present1, and drives mortality2, in the critical illness caused by coronavirus disease 2019 (COVID-19). Host genetic variants associated with critical illness may identify mechanistic targets for therapeutic development3. Here we report the results of the GenOMICC (Genetics Of Mortality In Critical Care) genome-wide association study in 2,244 critically ill patients with COVID-19 from 208 UK intensive care units. We have identified and replicated the following new genome-wide significant associations: on chromosome 12q24.13 (rs10735079, P = 1.65 × 10-8) in a gene cluster that encodes antiviral restriction enzyme activators (OAS1, OAS2 and OAS3); on chromosome 19p13.2 (rs74956615, P = 2.3 × 10-8) near the gene that encodes tyrosine kinase 2 (TYK2); on chromosome 19p13.3 (rs2109069, P = 3.98 ×  10-12) within the gene that encodes dipeptidyl peptidase 9 (DPP9); and on chromosome 21q22.1 (rs2236757, P = 4.99 × 10-8) in the interferon receptor gene IFNAR2. We identified potential targets for repurposing of licensed medications: using Mendelian randomization, we found evidence that low expression of IFNAR2, or high expression of TYK2, are associated with life-threatening disease; and transcriptome-wide association in lung tissue revealed that high expression of the monocyte-macrophage chemotactic receptor CCR2 is associated with severe COVID-19. Our results identify robust genetic signals relating to key host antiviral defence mechanisms and mediators of inflammatory organ damage in COVID-19. Both mechanisms may be amenable to targeted treatment with existing drugs. However, large-scale randomized clinical trials will be essential before any change to clinical practice
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