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Trends in extreme 100-y events of temperature and rainfall amounts in the continental United States are estimated, to see effects of climate change. This is a nontrivial statistical problem because climate change effects have to be extracted from "noisy" weather data within a limited time range. We use nonparametric Bayesian methods to estimate the trends of extreme events that have occurred between 1979 and 2019, based on data for temperature and rainfall. We focus on 100-y events for each month in [Formula: see text] geographical areas looking at hourly temperature and 5-d cumulative rainfall. Distribution tail models are constructed using extreme value theory (EVT) and data on 33-y events. This work shows it is possible to aggregate data from spatial points in diverse climate zones for a given month and fit an EVT model with the same parameters. This surprising result means there are enough extreme event data to see the trends in the 41-y record for each calendar month. The yearly trends of the risk of a 100-y high-temperature event show an average 2.1-fold increase over the last 41 y of data across all months, with a 2.6-fold increase for the months of July through October. The risk of high rainfall extremes increases in December and January 1.4-fold, but declines by 22% for the spring and summer months.
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Mudança Climática , Tempo (Meteorologia) , Estados Unidos , Teorema de Bayes , Estações do Ano , TemperaturaRESUMO
Strategic preparedness reduces the adverse health impacts of hurricanes and tropical storms, referred to collectively as tropical cyclones (TCs), but its protective impact could be enhanced by a more comprehensive and rigorous characterization of TC epidemiology. To generate the insights and tools necessary for high-precision TC preparedness, we introduce a machine learning approach that standardizes estimation of historic TC health impacts, discovers common patterns and sources of heterogeneity in those health impacts, and enables identification of communities at highest health risk for future TCs. The model integrates (i) a causal inference component to quantify the immediate health impacts of recent historic TCs at high spatial resolution and (ii) a predictive component that captures how TC meteorological features and socioeconomic/demographic characteristics of impacted communities are associated with health impacts. We apply it to a rich data platform containing detailed historic TC exposure information and records of all-cause mortality and cardiovascular- and respiratory-related hospitalization among Medicare recipients. We report a high degree of heterogeneity in the acute health impacts of historic TCs, both within and across TCs, and, on average, substantial TC-attributable increases in respiratory hospitalizations. TC-sustained windspeeds are found to be the primary driver of mortality and respiratory risks.
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Tempestades Ciclônicas , Idoso , Humanos , Estados Unidos , Medicare , Modelos Teóricos , CausalidadeRESUMO
Outbreaks of airborne viral emerging infectious diseases (EIDs) cause an increasing burden on global public health, particularly with a backdrop of intensified climate change. However, infection sources and drivers for outbreaks of airborne viral EIDs remain unknown. Here, we aim to explore the driving mechanisms of outbreaks based on the one health perspective. Outbreak information for 20 types of airborne viral EIDs was collected from the Global Infectious Disease and Epidemiology Network database and a systematic literature review. Four statistically significant and high-risk spatiotemporal clusters for airborne viral EID outbreaks were identified globally using multivariate scan statistic tests. There were 112 outbreaks with clear infection sources, and zoonotic spillover was the most common source (95.54%, 107/112). Since 1970, the majority of outbreaks occurred in healthcare facilities (24.82%), followed by schools (17.93%) and animal-related settings (15.93%). Significant associations were detected between the number of earthquakes, storms, duration of floods, and airborne viral EIDs' outbreaks using a case-crossover study design and multivariable conditional logistic regression. These findings implied that zoonotic spillover and extreme weather events are driving global outbreaks of airborne viral EIDs, and targeted prevention and control measures should be made to reduce the airborne viral EIDs burden.
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Doenças Transmissíveis Emergentes , Surtos de Doenças , Tempo (Meteorologia) , Zoonoses , Humanos , Animais , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Zoonoses/epidemiologia , Zoonoses/virologia , Zoonoses/transmissão , Saúde Global , Microbiologia do Ar , Viroses/epidemiologia , Viroses/transmissão , Viroses/virologia , Mudança ClimáticaRESUMO
Grain filling is a critical process for improving crop production under adverse conditions caused by climate change. Here, using a quantitative method, we quantified post-anthesis source-sink relationships of a large data set to assess the contribution of remobilized pre-anthesis assimilates to grain growth for both biomass and nitrogen. The data set came from 13 years' semi-controlled field experimentation, in which six bread wheat genotypes were grown at plot scale under contrasting temperature, water, and nitrogen regimes. On average, grain biomass was ~10% higher than post-anthesis aboveground biomass accumulation across regimes and genotypes. Overall, the estimated relative contribution (%) of remobilized assimilates to grain biomass became increasingly significant with increasing stress intensity, ranging from virtually nil to 100%. This percentage was altered more by water and nitrogen regimes than by temperature, indicating the greater impact of water or nitrogen regimes relative to high temperatures under our experimental conditions. Relationships between grain nitrogen demand and post-anthesis nitrogen uptake were generally insensitive to environmental conditions, as there was always significant remobilization of nitrogen from vegetative organs, which helped to stabilize the amount of grain nitrogen. Moreover, variations in the relative contribution of remobilized assimilates with environmental variables were genotype-dependent. Our analysis provides an overall picture of post-anthesis source-sink relationships and pre-anthesis assimilate contributions to grain filling across (non-)environmental factors, and highlights that designing wheat adaption to climate change should account for complex multi-factor interactions.
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Driven by climate change, tropical cyclones (TCs) are predicted to change in intensity and frequency through time. Given these forecasted changes, developing an understanding of how TCs impact insular wildlife is of heightened importance. Previous work has shown that extreme weather events may shape species distributions more strongly than climatic averages; however, given the coarse spatial and temporal scales at which TC data are often reported, the influence of TCs on species distributions has yet to be explored. Using TC data from the National Hurricane Center, we developed spatially and temporally explicit species distribution models (SDMs) to examine the role of TCs in shaping present-day distributions of Puerto Rico's 10 Anolis lizard species. We created six predictor variables to represent the intensity and frequency of TCs. For each occurrence of a species, we calculated these variables for TCs that came within 500 km of the center of Puerto Rico and occurred within the 1-year window prior to when that occurrence was recorded. We also included predictor variables related to landcover, climate, topography, canopy cover and geology. We used random forests to assess model performance and variable importance in models with and without TC variables. We found that the inclusion of TC variables improved model performance for the majority of Puerto Rico's 10 anole species. The magnitude of the improvement varied by species, with generalist species that occur throughout the island experiencing the greatest improvements in model performance. Range-restricted species experienced small, almost negligible, improvements but also had more predictive models both with and without the inclusion of TC variables compared to generalist species. Our findings suggest that incorporating data on TCs into SDMs may be important for modeling insular species that are prone to experiencing these types of extreme weather events.
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Tempestades Ciclônicas , Lagartos , Animais , Mudança Climática , Porto Rico , Animais Selvagens , PrevisõesRESUMO
Climate change is predicted to cause milder winters and thus exacerbate soil freeze-thaw perturbations in the subarctic, recasting the environmental challenges that soil microorganisms need to endure. Historical exposure to environmental stressors can facilitate the microbial resilience to new cycles of that same stress. However, whether and how such microbial memory or stress legacy can modulate microbial responses to cycles of frost remains untested. Here, we conducted an in situ field experiment in a subarctic birch forest, where winter warming resulted in a substantial increase in the number and intensity of freeze-thaw events. After one season of winter warming, which raised mean surface and soil (-8 cm) temperatures by 2.9 and 1.4°C, respectively, we investigated whether the in situ warming-induced increase in frost cycles improved soil microbial resilience to an experimental freeze-thaw perturbation. We found that the resilience of microbial growth was enhanced in the winter warmed soil, which was associated with community differences across treatments. We also found that winter warming enhanced the resilience of bacteria more than fungi. In contrast, the respiration response to freeze-thaw was not affected by a legacy of winter warming. This translated into an enhanced microbial carbon-use efficiency in the winter warming treatments, which could promote the stabilization of soil carbon during such perturbations. Together, these findings highlight the importance of climate history in shaping current and future dynamics of soil microbial functioning to perturbations associated with climate change, with important implications for understanding the potential consequences on microbial-mediated biogeochemical cycles.
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Resiliência Psicológica , Microbiologia do Solo , Estações do Ano , Solo/química , Carbono , Mudança ClimáticaRESUMO
Extreme weather events in South and Southeast Asia exert profound psychosocial impacts, amplifying the prevalence of mental illness. Despite their substantial consequences, there is a dearth of research and representation in the current literature. We conducted a systematic review of observational studies published between January 1, 2000, and January 20, 2024, to examine the impact of extreme weather events on the mental health of the South and Southeast Asian population. Quality assessment of the included studies was conducted using the Newcastle-Ottawa Scale (NOS) quality appraisal checklist. The search retrieved 70 studies that met the inclusion criteria and were included in our review. Most were from India (n = 22), and most used a cross-sectional study design (n = 55). Poor mental health outcomes were associated with six types of extreme weather events: floods, storm surges, typhoons, cyclones, extreme heat, and riverbank erosion. Most studies (n = 41) reported short-term outcome measurements. Findings included outcomes with predictable symptomatology, including post-traumatic stress disorder, depression, anxiety, general psychological distress, emotional distress and suicide. Limited studies on long-term effects showed higher mental disorders after floods and typhoons, while cyclone-exposed individuals had more short-term distress. Notably, the review identified over 50 risk factors influencing mental health outcomes, categorized into six classes: demographic, economic, health, disaster exposure, psychological, and community factors. However, the quantitative evidence linking extreme weather events to mental health was limited due to a lack of longitudinal data, lack of control groups, and the absence of objective exposure measurements. The review found some compelling evidence linking extreme weather events to adverse mental health in the South and Southeast Asia region. Future research should focus on longitudinal study design to identify the specific stressors and climatic factors influencing the relationship between climate extremes and mental health in this region.
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Clima Extremo , Saúde Mental , Humanos , Saúde Mental/estatística & dados numéricos , Sudeste Asiático/epidemiologia , Transtornos Mentais/epidemiologia , Estudos Observacionais como AssuntoRESUMO
INTRODUCTION: Climate change presents a significant risk for the mental and physical health of young people. In order to identify and properly care for potential mental health impairments from extreme weather events, the relevance of these impairments must be assessed as high by the professional groups providing care for children and adolescents. This raises the question of which factors influence the individual relevance assessment of caretaking professionals? METHODS: Data was collected creating and conducting a Germany-wide online questionnaire via LimeSurvey. The questionnaire was addressed to professionals providing care for children and adolescents, in this case medical and therapeutic personnel as well as school and pedagogical personnel. Professional associations, chief physicians and school principals were contacted as multipliers and asked to forward the questionnaire to their members and staff. The data was analyzed using the R statistical software, and multiple linear regressions were performed to test the hypotheses. RESULTS: Overall, 648 questionnaires were taken into analysis. Approximately 70% of the participants considered climate change-induced impacts on the mental health of children and adolescents due to extreme weather events as relevant. Experiencing heat, storm, heavy precipitation, flood/flooding, and/or avalanches/mudflows made a modest yet significant contribution to explaining higher relevance assessments. In contrast, there was no evidence to suggest that an urban working environment increases the relevance assessment. CONCLUSION: The described influence of experiencing extreme weather events should not be regarded as the sole factor leading to higher relevance ratings. A more comprehensive understanding of the factors influencing relevance assessments is necessary to address key aspects of risk communication and increase risk awareness.
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Clima Extremo , Deficiência Intelectual , Criança , Humanos , Adolescente , Saúde Mental , Mudança Climática , Alemanha/epidemiologiaRESUMO
We explore the causal connection between weather and war by constructing and analyzing a dataset featuring extreme weather events and military conflicts involving a set of stable political entities that existed side by side over several centuries, namely, the three ancient kingdoms of the Korean Peninsula between 18 Before the Common Era and 660 Common Era. Conflicts are classified as desperate if a state experiencing the shock invades a neighbor and opportunistic if a state experiencing the shock is invaded by a neighbor. We find that weather-induced conflict was significant, but largely opportunistic rather than desperate. That is, states experiencing an adverse shock were more likely to be invaded, but not more likely to initiate attack. We also provide evidence that the channel through which weather shocks gave rise to opportunistic invasions was food insecurity, which weakened the power of states to repel attack. Since climate change is projected to give rise to an increased frequency of extreme weather events, these historical findings have contemporary relevance.
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Sanitation infrastructure can fail during heavy rainfall and flooding, allowing the release of fecal waste - and the pathogens it carries - into spaces where people live, work, and play. However, there is a scarcity of reliable frameworks that can effectively assess the resilience of such infrastructure to extreme rainfall and flooding events. The purpose of this study was to develop and apply a novel framework for assessing and ranking the resilience of sanitation infrastructure in informal settlements. A framework for assessing sanitation infrastructure resilience was developed consisting of 19 indicators that were categorized into three domains: physical infrastructure design (8 indicators), operations and management (5 indicators), and environmental factors (6 indicators). The framework was applied to data from 200 shared sanitation facilities in Kibera, Kenya, collected through transect walks, field observations, surveys, and sanitary risk inspections. Results indicate that sanitation infrastructure type impacts resilience. Toilet facilities connected to a piped sewer (r = 1.345, 95% CI: 1.19-1.50) and toilets connected to a septic system (r = 1.014, 95% CI: 0.78-1.25) demonstrated higher levels of resilience compared to latrines (r = 0.663, 95% CI: 0.36-0.97) and hanging toilets (r = 0.014, 95% CI: 0.30-0.33) on a scale ranging from 0 to 4. The key determinants of sanitation infrastructure resilience were physical design, functionality, operational and maintenance routines, and environmental factors. This evidence provides valuable insights for developing standards and guidelines for the design and safe siting of new sanitation infrastructure and encourages investment in sewer and septic systems as superior options for resilient sanitation infrastructure. Additionally, our findings underscore the importance for implementers and communities to prioritize repairing damaged infrastructure, sealing potential discharge points into open drains, and emptying filled containment systems before the onset of the rainy season.
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Resiliência Psicológica , Saneamento , Humanos , Saneamento/métodos , Quênia , Inundações , BanheirosRESUMO
BACKGROUND: Climate Change is causing frequent and sever extreme weather events globally, impacting human health and well-being. Primary healthcare (PHC) nurses' are at the forefront of addressing these challenges and must be prepared. PURPOSE: This scoping revieww explored literature on the preparedness of the PHC nursing workforce for extreme weather events and identify gaps in knowledge and practice. METHODS: Using Arksey and O'Malley's framework, a comprehensive search was conducted across PubMed, Scopus, CINHAL, Web of Sciences, and ProQuest, on studies from 2014-2024, addressing PHC nurses' preparedness. DISCUSSION: Nine studies were identified and highlighted a need for preparedness training and facility-based preparedness plans. Key themes included prioritizing regional networks, clinical leadership, service delivery, health information, health workforce, medical products and technologies, and financing. CONCLUSION: Strengthening PHC nurses' resilience against extreme weather requires targeted professional development, mental health support, comprehensive planning, and collaborative efforts. Future strategies should enhance PHC nurses' capacity through training, support, and policy development.
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The alarming increase in extreme weather events, such as severe storms with torrential rain and strong winds, is a direct result of climate change. These events have led to discernible shifts in forest structure and the carbon cycle, primarily driven by a surge in tree mortality. However, the impacts caused by these severe storms on the production and carbon increment from coarse woody debris (CWD) are still poorly understood, especially in the Brazilian Atlantic Forest. Thus, the goal proposed by the study was to quantify the CWD volume, necromass, and carbon stock before and after the occurrence of a severe storm and to determine the importance of spatial, structural, and qualitative variables of trees in the CWD carbon increment. The increase in carbon by the storm was 2.01 MgC ha-1, with a higher concentration in the CWD less decomposed and smaller diameter class. The forest fragment plots showed distinct increments (0.05-0.35 MgC), being influenced by spatial (elevation, declivity, and slope angle) structural (basal area) and qualitative factors (trunk quality and tree health), intrinsic to the forest. Thus, it is concluded that severe storms cause a large increase in carbon in CWD, making it essential to understand the susceptibility of forests to the action of intense rains and strong winds to model and monitor the future impacts of these extreme weather events on Atlantic Forest and other tropical forests in the world.
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Carbono , Monitoramento Ambiental , Brasil , Florestas , Madeira , Árvores , Clima Tropical , BiomassaRESUMO
BACKGROUND AND AIM: Heat and heavy rain can have negative health impacts for people in Germany. Vulnerable groups in particular, such as children and the elderly, are at increased risk and require special precautions. This paper examines how employers of the municipal administration and facilitating organisations perceive the risk of heat and heavy rain for daycare centres and care facilities, and to what extent an exchange takes place between the municipal level and the facilities. In addition, specially developed information materials with recommendations for action for adapting to heat and heavy rain that are aimed at such facilities were evaluated. METHODS: In the summer of 2021, we conducted a quantitative survey. A total of 333 respondents from municipal administrations, facilitating organisations and institutions participated. Descriptive analyses and ANOVAs were conducted. RESULTS: Risk perception and adaptation knowledge concerning heat was perceived higher than concerning heavy rain. The intention to support institutions in finding measures for adaptation was also higher with regard to heat. The majority of interviewees from municipal administrations and institutions communicated with institutions through various channels on different topics including the natural hazards mentioned. The information material was evaluated positively. DISCUSSION: This article shows that facilities are seen as very affected by heat waves. Awareness towards heavy rainfall needs to be raised. The feedback on the information material clearly shows a high need in this area.
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Creches , Chuva , Humanos , Alemanha , Creches/estatística & dados numéricos , Creches/normas , Criança , Temperatura Alta , Medição de Risco , Pré-Escolar , Feminino , Comunicação , Inquéritos e Questionários , Idoso , Masculino , Transtornos de Estresse por Calor/prevenção & controleRESUMO
One of the primary ways in which climate change will impact coastal freshwater wetlands is through changes in the frequency, intensity, timing and distribution of extreme weather events. Disentangling the direct and indirect mechanisms of population- and community-level responses to extreme events is vital to predicting how species composition of coastal wetlands will change under future conditions. We extended static structural equation modelling approaches to incorporate system dynamics in a multi-year multispecies occupancy model to quantify the effects of extreme weather events on a coastal freshwater wetland system. We used data from an 8-year study (2009-2016) on St. Marks National Wildlife Refuge in Florida, USA, to quantify species-specific and community-level changes in amphibian and fish occupancy associated with two flooding events in 2012 and 2013. We examine how physical changes to the landscape, including potential changes in salinity and increased wetland connectivity, may have contributed to or exacerbated the effects of these extreme weather events on the biota of isolated coastal wetlands. We provide evidence that the primary effects of flooding on the amphibian community were through indirect mechanisms via changes in the composition of the sympatric fish community that may have had lethal (i.e. through direct predation) or non-lethal (i.e. through direct or indirect competitive interactions) effects. In addition, we have shown that amphibian species differed in their sensitivity to direct flooding effects and indirect changes in the fish community and wetland-specific conductance, which led to variable responses across the community. These effects led to the overall decline in amphibian species richness from 2009 to 2016, suggesting that wetland-breeding amphibian communities on St. Marks National Wildlife Refuge may not be resilient to predicted changes in coastal disturbance regimes because of climate change. Understanding both direct and indirect effects, as well as species interactions, is important for predicting the effects of a changing climate on individual species, communities and ecosystems.
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Ecossistema , Áreas Alagadas , Animais , Biota , Animais Selvagens , SalinidadeRESUMO
BACKGROUND: People with HIV (PWH) are disproportionately vulnerable to the impacts of wildfires, given the need for frequent access to healthcare systems, higher burden of comorbidities, higher food insecurity, mental and behavioral health challenges, and challenges of living with HIV in a rural area. In this study, we aim to better understand the pathways through which wildfires impact health outcomes among PWH. METHODS: From October 2021 through February 2022, we conducted individual semi-structured qualitative interviews with PWH impacted by the Northern California wildfires and clinicians of PWH who were impacted by wildfires. The study aims were to explore the influence of wildfires on the health of PWH and to discuss measures at the individual, clinic, and system levels that helped to mitigate these impacts. RESULTS: We interviewed 15 PWH and 7 clinicians. While some PWH felt that surviving the HIV epidemic added to their resilience against wildfires, many felt that the wildfires compounded the HIV-related traumas that they have experienced. Participants outlined five main routes by which wildfires negatively impacted their health: (1) access to healthcare (medications, clinics, clinic staff), (2) mental health (trauma; anxiety, depression, or stress; sleep disturbances; coping strategies), (3) physical health (cardiopulmonary, other co-morbidities), (4) social/economic impacts (housing, finances, community), and (5) nutrition and exercise. The recommendations for future wildfire preparedness were at the (1) individual-level (what to have during evacuation), (2) pharmacy-level (procedural, staffing), and (3) clinic- or county-level (funds and vouchers; case management; mental health services; emergency response planning; other services such as telehealth, home visits, home laboratory testing). CONCLUSIONS: Based on our data and prior research, we devised a conceptual framework that acknowledges the impact of wildfires at the community-, household-, and individual-level with implications for physical and mental health outcomes among PWH. These findings and framework can help in developing future interventions, programs, and policies to mitigate the cumulative impacts of extreme weather events on the health of PWH, particularly among individuals living in rural areas. Further studies are needed to examine health system strengthening strategies, innovative methods to improve access to healthcare, and community resilience through disaster preparedness. TRIAL REGISTRATION: N/A.
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Desastres , Clima Extremo , Infecções por HIV , Incêndios Florestais , Humanos , California/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/psicologiaRESUMO
Complex, multihazard risks such as private groundwater contamination necessitate multiannual risk reduction actions including seasonal, weather-based hazard evaluations. In the Republic of Ireland (ROI), high rural reliance on unregulated private wells renders behavior promotion a vital instrument toward safeguarding household health from waterborne infection. However, to date, pathways between behavioral predictors remain unknown while latent constructs such as extreme weather event (EWE) risk perception and self-efficacy (perceived behavioral competency) have yet to be sufficiently explored. Accordingly, a nationwide survey of 560 Irish private well owners was conducted, with structural equation modeling (SEM) employed to identify underlying relationships determining key supply management behaviors. The pathway analysis (SEM) approach was used to model three binary outcomes: information seeking, post-EWE action, and well testing behavior. Upon development of optimal models, perceived self-efficacy emerged as a significant direct and/or indirect driver of all three behavior types-demonstrating the greatest indirect effect (ß = -0.057) on adoption of post-EWE actions and greatest direct (ß = 0.222) and total effect (ß = 0.245) on supply testing. Perceived self-efficacy inversely influenced EWE risk perception in all three models but positively influenced supply awareness (where present). Notably, the presence of a vulnerable (infant and/or elderly) household member negatively influenced adoption of post-EWE actions (ß = -0.131, p = 0.016). Results suggest that residential and age-related factors constitute key demographic variables influencing risk mitigation and are strongly mediated by cognitive variables-particularly self-efficacy. Study findings may help contextualize predictors of private water supply management, providing a basis for future risk-based water interventions.
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Água Subterrânea , Abastecimento de Água , Humanos , Idoso , Análise de Classes Latentes , Água Subterrânea/química , Irlanda , Comportamento de Redução do RiscoRESUMO
OBJECTIVES: The health impacts of climate change are increasing, but qualitative evidence on people's perceptions is limited. This qualitative study investigated people's perceptions of climate change and its impacts on health. STUDY DESIGN: This was an online study using semistructured interviews. METHODS: A total of 41 semistructured interviews were conducted in 2021 with members of the public aged ≥15 years living in England, recruited via community-based groups. Data were analysed using reflexive thematic analysis. RESULTS: Participants were concerned about climate change, which was often perceived as extreme weather events happening elsewhere. Changes in the UK's seasons and weather patterns were noted, but participants were uncertain whether these changes resulted from climate change. Participants often struggled to identify health impacts of climate change; where health impacts were described, they tended to be linked to extreme weather events outside the United Kingdom and their associated threats to life. The mental health impacts of such events were also noted. CONCLUSIONS: The study found that most participants did not perceive climate change to be affecting people's health in England. This raises questions about whether framing climate change as a health issue, an approach advocated for countries less exposed to the direct effects of climate change, will increase its salience for the British public.
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Mudança Climática , Tempo (Meteorologia) , Humanos , Reino Unido , Pesquisa Qualitativa , InglaterraRESUMO
The recent COVID-19 pandemic has led to a nearly world-wide shelter-in-place strategy. This raises several natural concerns about the safe relaxing of current restrictions. This article focuses on the design and operation of heating ventilation and air conditioning (HVAC) systems in the context of transportation. Do HVAC systems have a role in limiting viral spread? During shelter-in-place, can the HVAC system in a dwelling or a vehicle help limit spread of the virus? After the shelter-in-place strategy ends, can typical workplace and transportation HVAC systems limit spread of the virus? This article directly addresses these and other questions. In addition, it also summarizes simplifying assumptions needed to make meaningful predictions. This article derives new results using transform methods first given in Ginsberg and Bui. These new results describe viral spread through an HVAC system and estimate the aggregate dose of virus inhaled by an uninfected building or vehicle occupant when an infected occupant is present within the same building or vehicle. Central to these results is the derivation of a quantity called the "protection factor"-a term-of-art borrowed from the design of gas masks. Older results that rely on numerical approximations to these differential equations have long been lab validated. This article gives the exact solutions in fixed infrastructure for the first time. These solutions, therefore, retain the same lab validation of the older methods of approximation. Further, these exact solutions yield valuable insights into HVAC systems used in transportation.
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BACKGROUND: Vulnerabilities of men and women to adverse health effects due to weather variability and climate change are not equal. Uganda was among the countries in the world most affected by extreme weather events during the last decade. However, there is still limited gendered empirical evidence on the links between weather variability and health and the possible pathways through which these health effects occur. Therefore, this study analyses the effect of weather variability on illness, and the extent to which water collection 'time burden' mediates the relationship between weather anomalies and illness among men and women of working age in Uganda. The study also quantifies the health inequalities to be eliminated if resources are equalized. METHODS: Socioeconomic, health and time use data were obtained from the World Bank Living Standards Measurement Studies - Integrated Surveys on Agriculture (LSMS -ISA), combined with high resolution remotely-sensed weather data. Two-parts and non-linear decomposition regression analysis were used on the national representative pooled dataset from the four household survey waves collected between 2009 to 2014, comprising a total of 22,469 men and women aged between 15 and 64 years. RESULTS: Empirical results show that low rainfall below the long-term mean increased the likelihood of illness by at least 8 and 6 percentage points for women and men, respectively. The indirect effect of low rainfall on illness through water access pathway was estimated at 0.16 percentage points in women. Decomposition results reveal that health inequalities among women and men would have been narrowed by 27-61%, if endowments were equalized. CONCLUSIONS: Strategies that promote women empowerment (such as education, labor force participation, access to financial services and clean water), health adaptation and time poverty reduction strategies (such as rain water harvesting and improved access to quality health care) would reduce gender-based health inequalities in Uganda despite changing climatic conditions.