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1.
Washington, D.C.; PAHO; 2021-10-12.
Não convencional em Inglês | PAHO-IRIS | ID: phr-54979

RESUMO

This publication presents a comprehensive methodology to support the Member States of the Pan American Health Organization (PAHO) in preparing for and responding to heat-health risks in the Region of the Americas. It builds on World Health Organization and the World Meteorological Organization global documents, as well as on the disaster preparedness methodologies employed throughout the countries of the Region. This publication is part of an effort coordinated by PAHO to support Member States in multihazard preparedness, and includes: early warning system strengthening; threat characterization; activation and deactivation procedure definition; and institutional coordination. It engages different disciplines and recognizes the importance of intersectoral collaboration to respond to heat-health risks. It aims to bring awareness of the impacts of heat on the health of people of the Americas to public health decisionmakers, and thereby strengthen health service provision.


Assuntos
Preparativos para Desastre , Calefação , Onda de Calor , Mudança Climática , Saúde Pública , Medição de Risco , Tomada de Decisões , Efeitos do Clima , Aquecimento Global
3.
Ned Tijdschr Geneeskd ; 1652021 09 20.
Artigo em Holandês | MEDLINE | ID: mdl-34542941

RESUMO

More than 230 medical journals have called for worldwide action against global warming and for nature restoration. They call on health professionals to actively contribute to increasing support for the radical measures necessary to maintain the health and well-being of life on our planet. This call concerns not only making one's own living and working environment greener, but above all the use of medical knowledge, expertise and authority for measures that matter worldwide. This starts with concrete advice to patients to prevent damage from climate change at an individual level. Health workers must stand up for prevention and care outside the consultation room and across national borders. After all, medical doctors have historically been in a position to speak out about these threats and to remind political leaders of their responsibility.Health professionals can lead by example by realizing greener and more sustainable care themselves.


Assuntos
Médicos , Aquecimento Global , Humanos
4.
Elife ; 102021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34550071

RESUMO

The ability of corals to adapt to global warming may involve trade-offs among the traits that influence their success as the foundational species of coral reefs.


Assuntos
Antozoários , Recifes de Corais , Animais , Aquecimento Global
7.
Nature ; 597(7875): 230-234, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34497394

RESUMO

Parties to the 2015 Paris Agreement pledged to limit global warming to well below 2 °C and to pursue efforts to limit the temperature increase to 1.5 °C relative to pre-industrial times1. However, fossil fuels continue to dominate the global energy system and a sharp decline in their use must be realized to keep the temperature increase below 1.5 °C (refs. 2-7). Here we use a global energy systems model8 to assess the amount of fossil fuels that would need to be left in the ground, regionally and globally, to allow for a 50 per cent probability of limiting warming to 1.5 °C. By 2050, we find that nearly 60 per cent of oil and fossil methane gas, and 90 per cent of coal must remain unextracted to keep within a 1.5 °C carbon budget. This is a large increase in the unextractable estimates for a 2 °C carbon budget9, particularly for oil, for which an additional 25 per cent of reserves must remain unextracted. Furthermore, we estimate that oil and gas production must decline globally by 3 per cent each year until 2050. This implies that most regions must reach peak production now or during the next decade, rendering many operational and planned fossil fuel projects unviable. We probably present an underestimate of the production changes required, because a greater than 50 per cent probability of limiting warming to 1.5 °C requires more carbon to stay in the ground and because of uncertainties around the timely deployment of negative emission technologies at scale.


Assuntos
Conservação de Recursos Energéticos/legislação & jurisprudência , Combustíveis Fósseis/análise , Combustíveis Fósseis/provisão & distribuição , Aquecimento Global/prevenção & controle , Cooperação Internacional/legislação & jurisprudência , Modelos Teóricos , Temperatura , Óleos Combustíveis/análise , Óleos Combustíveis/provisão & distribuição , Mapeamento Geográfico , Aquecimento Global/legislação & jurisprudência , Metano/análise , Metano/provisão & distribuição , Paris , Probabilidade , Fatores de Tempo , Incerteza
8.
Nat Commun ; 12(1): 5483, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531387

RESUMO

Eukaryotic phytoplankton are responsible for at least 20% of annual global carbon fixation. Their diversity and activity are shaped by interactions with prokaryotes as part of complex microbiomes. Although differences in their local species diversity have been estimated, we still have a limited understanding of environmental conditions responsible for compositional differences between local species communities on a large scale from pole to pole. Here, we show, based on pole-to-pole phytoplankton metatranscriptomes and microbial rDNA sequencing, that environmental differences between polar and non-polar upper oceans most strongly impact the large-scale spatial pattern of biodiversity and gene activity in algal microbiomes. The geographic differentiation of co-occurring microbes in algal microbiomes can be well explained by the latitudinal temperature gradient and associated break points in their beta diversity, with an average breakpoint at 14 °C ± 4.3, separating cold and warm upper oceans. As global warming impacts upper ocean temperatures, we project that break points of beta diversity move markedly pole-wards. Hence, abrupt regime shifts in algal microbiomes could be caused by anthropogenic climate change.


Assuntos
Variação Genética , Microalgas/genética , Microbiota/genética , Fitoplâncton/genética , Transcriptoma/genética , Regiões Antárticas , Regiões Árticas , Biodiversidade , Ciclo do Carbono , Mudança Climática , Ontologia Genética , Geografia , Aquecimento Global , Microalgas/classificação , Microalgas/crescimento & desenvolvimento , Oceanos e Mares , Fitoplâncton/classificação , Fitoplâncton/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA/métodos , Especificidade da Espécie , Temperatura
9.
Artigo em Espanhol | PAHO-IRIS | ID: phr-54701

RESUMO

[Extract]. En septiembre del 2021, la Asamblea General de las Naciones Unidas reunirá a los países en un momento crucial para orga-nizar la acción colectiva con el propósito de hacer frente a la crisis medioambiental mundial. Se reunirán una vez más en la Conferencia de las Naciones Unidas sobre la Diversidad Bioló-gica, en Kunming (China) y en la Conferencia de las Naciones Unidas sobre el Cambio Climático (CP26), en Glasgow (Escocia). Antes de la celebración de estas reuniones trascendenta-les, nosotros —los editores de revistas sobre salud de todo el mundo— exigimos medidas urgentes para mantener los aumen-tos promedio de la temperatura a nivel mundial por debajo de 1,5 °C, detener la destrucción de la naturaleza y proteger la salud.


Assuntos
Biodiversidade , Temperatura , Saúde Ambiental , Aquecimento Global , COVID-19 , Coronavirus , Emergências
10.
Nat Commun ; 12(1): 5226, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471105

RESUMO

Marine phytoplankton and zooplankton form the basis of the ocean's food-web, yet the impacts of climate change on their biodiversity are poorly understood. Here, we use an ensemble of species distribution models for a total of 336 phytoplankton and 524 zooplankton species to determine their present and future habitat suitability patterns. For the end of this century, under a high emission scenario, we find an overall increase in plankton species richness driven by ocean warming, and a poleward shift of the species' distributions at a median speed of 35 km/decade. Phytoplankton species richness is projected to increase by more than 16% over most regions except for the Arctic Ocean. In contrast, zooplankton richness is projected to slightly decline in the tropics, but to increase strongly in temperate to subpolar latitudes. In these latitudes, nearly 40% of the phytoplankton and zooplankton assemblages are replaced by poleward shifting species. This implies that climate change threatens the contribution of plankton communities to plankton-mediated ecosystem services such as biological carbon sequestration.


Assuntos
Biodiversidade , Aquecimento Global , Biologia Marinha , Plâncton/classificação , Animais , Regiões Árticas , Mudança Climática , Ecossistema , Cadeia Alimentar , Fitoplâncton , Temperatura , Zooplâncton
12.
Plant Sci ; 311: 111007, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482910

RESUMO

Historically, extended droughts combined with heat waves caused severe reductions in crop yields estimated at billions of dollars annually. Because global warming and climate change are driving an increase in the frequency and intensity of combined water-deficit and heat stress episodes, understanding how these episodes impact yield is critical for our efforts to develop climate change-resilient crops. Recent studies demonstrated that a combination of water-deficit and heat stress exacerbates the impacts of water-deficit or heat stress on reproductive processes of different cereals and legumes, directly impacting grain production. These studies identified several different mechanisms potentially underlying the effects of stress combination on anthers, pollen, and stigma development and function, as well as fertilization. Here we review some of these findings focusing on unbalanced reactive oxygen accumulation, altered sugar concentrations, and conflicting functions of different hormones, as contributing to the reduction in yield during a combination of water-deficit and heat stress. Future studies focused on the effects of water-deficit and heat stress combination on reproduction of different crops are likely to unravel additional mechanisms, as well as reveal novel ways to develop stress combination-resilient crops. These could mitigate some of the potentially devastating impacts of this stress combination on agriculture.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Desidratação/fisiopatologia , Secas , Resposta ao Choque Térmico/fisiologia , Magnoliopsida/crescimento & desenvolvimento , Reprodução/fisiologia , Estresse Fisiológico , Mudança Climática , Aquecimento Global
15.
Sci Total Environ ; 799: 149166, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34364272

RESUMO

Summertime extreme heat events exert severe impacts on the natural environment and human society, especially in densely populated and highly urbanized regions. While previous studies have focused on independent heat day/night, there is a lack of attention to the changes in compound events with cooccurring daytime and nighttime extreme temperature on the same day. In this study, we examine the spatio-temporal changes of summertime compound heat extremes (including compound heat day and compound heatwave) across China, with a particular focus on 20 major urban agglomerations (UAs), and quantify the urbanization effects on these changes. We find that the frequency and fraction of compound heat events show obvious spatial disparities across China. The compound heat events occur more frequently in highly populated and urbanized areas such as the Pearl River Delta. Moreover, the frequency and fraction of compound heat events have significantly increased in recent decades in most parts of China, especially in more developed UAs. These intensifying trends have even accelerated in more recent decades. Our further investigations suggest that most UAs of China experienced an intensifying urbanization effect on compound heat events, and few UAs in northwestern and central China (e.g., UAs of the north Tianshan mountain and the middle reaches of the Yangtze River) display a weakening effect of urbanization. Our findings highlight the important role of urbanization in increasing compound heat extremes and suggest that the increasing threats of compound events in urban areas should be given more attention under the context of global warming and local urbanization.


Assuntos
Temperatura Alta , Urbanização , China , Cidades , Aquecimento Global , Humanos , Rios
16.
Elife ; 102021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34387190

RESUMO

Climate change is dramatically changing ecosystem composition and productivity, leading scientists to consider the best approaches to map natural resistance and foster ecosystem resilience in the face of these changes. Here, we present results from a large-scale experimental assessment of coral bleaching resistance, a critical trait for coral population persistence as oceans warm, in 221 colonies of the coral Acropora hyacinthus across 37 reefs in Palau. We find that bleaching-resistant individuals inhabit most reefs but are found more often in warmer microhabitats. Our survey also found wide variation in symbiont concentration among colonies, and that colonies with lower symbiont load tended to be more bleaching-resistant. By contrast, our data show that low symbiont load comes at the cost of lower growth rate, a tradeoff that may operate widely among corals across environments. Corals with high bleaching resistance have been suggested as a source for habitat restoration or selective breeding in order to increase coral reef resilience to climate change. Our maps show where these resistant corals can be found, but the existence of tradeoffs with heat resistance may suggest caution in unilateral use of this one trait in restoration.


Assuntos
Antozoários/crescimento & desenvolvimento , Antozoários/parasitologia , Recifes de Corais , Variação Genética , Aquecimento Global , Simbiose , Termotolerância , Animais , Antozoários/genética , Clorofila/análise , Conservação dos Recursos Naturais , Palau , Simbiose/genética , Termotolerância/genética
17.
Artigo em Inglês | PAHO-IRIS | ID: phr-54653

RESUMO

[EXTRACT]. The UN General Assembly in September 2021 will bring coun-tries together at a critical time for marshalling collective action to tackle the global environmental crisis. They will meet again at the biodiversity summit in Kunming, China, and the climate conference (COP26) in Glasgow, UK. Ahead of these pivotal meetings, we—the editors of health journals worldwide—call for urgent action to keep average global temperature increases below 1.5°C, halt the destruction of nature, and protect health.Health is already being harmed by global temperature increa-ses and the destruction of the natural world, a state of affairs health professionals have been bringing attention to for decades.1The science is unequivocal; a global increase of 1.5°C above the pre-industrial average and the continued loss of biodiversity risk catastrophic harm to health that will be impossible to reverse.2,3Despite the world’s necessary preoccupation with COVID-19, we cannot wait for the pandemic to pass to rapidly reduce emissions.Reflecting the severity of the moment, this editorial appears in health journals across the world. We are united in recogni-sing that only fundamental and equitable changes to societies will reverse our current trajectory.


Assuntos
Biodiversidade , Temperatura , COVID-19 , Emergências , Saúde Ambiental , Aquecimento Global
18.
Waste Manag ; 134: 206-219, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34454187

RESUMO

Chemical recycling could facilitate the transition from a linear to a circular carbon economy, where carbon-containing waste is channeled back into the production cycle as a chemical feedstock instead of being incinerated or landfilled. However, the predominant focus on technological aspects of chemical recycling for plastic waste narrows evaluations of its potential in contributing to such a transition. Moreover, it leads to significant controversy about its role in the waste hierarchy as a possible competitor to mechanical recycling. To address these gaps in the literature, this study assesses ecological and economic impacts associated with chemical recycling of residual municipal solid waste in Germany. Combining approaches of life cycle assessment and techno-economic analysis, chemical recycling and conventional incineration-based treatment pathways are comparatively evaluated in terms of global warming potential and economic performance (i.e. fixed capital investment, net present value, dynamic payback period, and levelized cost of carbon abatement). Results indicate that compared to incineration-based conventional pathways, chemical recycling can contribute to reducing greenhouse gas emissions in low-emission energy systems. However, the economic performance of chemical recycling is highly dependent on its scale of operation. Additionally, a price premium for recycling products as well as economic instruments for penalizing CO2 emissions are identified to play important roles in the economic performance of chemical recycling.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Aquecimento Global , Incineração , Reciclagem , Resíduos Sólidos/análise
19.
J Environ Manage ; 298: 113474, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34364244

RESUMO

China is the second largest irrigated country in the world. Increasing irrigation intensity costs more water and energy, and produces more greenhouse gas (GHG). In the present study, the responses of maize economic and environmental benefits to different irrigation managements were analyzed in a 2-year field study. A purposely designed tube-study was conducted to explore mechanism underlying effects of irrigation managements in detail. Three treatments, rainfed (RF), flood irrigation (FI), and drip irrigation (DI) were included in the field. Five treatments, no irrigation, flood irrigation, irrigation in 0-30, 30-60, and 0-90 cm depth were conducted in the tube study. Compared to RF, grain yields of FI and DI significantly increased by 22.1 % and 35.7 %, respectively, the net ecosystem economic budget significantly increased by 34.2 % and 35.6 %, and carbon footprint decreased by 7.0 % and 12.7 % in the field study. The irrigation treatments in the tube study increased the global warming potential by 12.0-32.8 % and grain yield by 44.5-203.9 %, and reduced GHG intensity by 24.3-57.4 %, compared with no irrigation treatment. Water content at the top soil layer had the greatest impact on GHG emissions. In conclusion, the differences in grain yield and GHG emissions among irrigation managements are mainly due to the soil water content in space and time. Drip irrigation decreases GHG intensity by producing more grain yield due to the optimized soil water distribution in the root zone. Irrigation management with appropriate amount and frequency can increase economic benefit and reduce environmental cost in maize production.


Assuntos
Aquecimento Global , Zea mays , Irrigação Agrícola , Agricultura , China , Ecossistema , Óxido Nitroso/análise , Solo
20.
J Environ Manage ; 298: 113384, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34371218

RESUMO

The Paris Agreement (COP21) sets out a global framework to limit global warming below 2C. Therefore, the target of carbon neutrality has a key role. In this context, countries have implemented cap-and-trade markets of carbon emissions allowances to manage the impact of CO2 released by companies. Over recent years, cryptocurrencies have given a new drive to pollution because of the massive energy consumption of mining activity. This paper investigates the tail relationship between the carbon credit market and the price of Bitcoin. For this purpose, we use two novel econometric models: the multivariate-quantile conditional autoregressive (MVMQ-CAViaR) model and Granger causality across quantiles. The results suggest that there is a downside risk spillover, i.e., tail co-dependence. We find that Bitcoin spillovers have a stronger impact on the carbon market. On the other hand, we show that the carbon market does not Granger-cause Bitcoin. The results of the Granger analysis confirm the multivariate quantile model's findings, i.e., Bitcoin influences the carbon market in the lower quantiles. We deem our results useful for policymakers to improve the framework of carbon emissions allowances.


Assuntos
Carbono , Desenvolvimento Econômico , Dióxido de Carbono/análise , Poluição Ambiental , Aquecimento Global
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