Environmental Research Letters最新文献

Climate change increases fire weather globally. Hot, dry and windy conditions raise the likelihood of fires igniting and spreading and make suppression more challenging. With further warming, fire weather is projected to intensify across Europe, yet implications for today's young generations remain unclear. Here, we analyse lifetime exposure to extreme fire weather across Europe using an ensemble of bias-adjusted and downscaled global climate models. To this end, we developed dem4cli, an open-source Python package that integrates demographic data into climate hazard assessments. We find younger generations are projected to be disproportionately exposed compared to older generations across all warming pathways, while also benefitting most from ambitious mitigation. Across Europe, individuals born in 2025 are projected to experience, on average, 3.2 additional years of exposure to extreme fire weather compared to those born in 1950, corresponding to an 84% increase, with larger increases observed in Southern and Eastern Europe. Focusing on Portugal, under current policies, people born in 2025 are projected to experience nearly twice the exposure compared with those born in 1950, and up to 2.5 times more in the most exposed regions of northeastern Portugal. Under a 1.5 ${}^{\circ }$  C pathway, lifetime exposure is substantially reduced. Each additional degree of global warming by 2100 adds approximately 270 days of extreme fire weather to the lifetime exposure of a person born in Portugal in 2025. These results reveal pronounced intergenerational inequalities in exposure to fire weather and underscore the urgency of ambitious mitigation to limit cumulative exposure for younger generations.

Reducing ultra-processed food (UPF) consumption is widely proposed to improve population health, but whether it also generates environmental co-benefits depends on the foods that replace UPFs in the diet. We developed a comparative risk assessment macrosimulation using nationally representative dietary data from Argentina to estimate the mortality and economic burden attributable to UPF consumption and to evaluate policy-relevant reduction scenarios. The scenarios reduced UPF exposure without replacement or replaced the displaced dietary energy or food mass using alternative baskets, including one aligned with the National Dietary Guidelines. We also decomposed the environmental effects of the guideline-concordant basket by food group. In 2019, UPF consumption was associated with 9823 premature deaths, 349 686 years of life lost, and 0.84 billion international dollars in indirect costs. Under the most ambitious reduction target, alternative replacement baskets averted the same 8747 deaths but produced markedly different environmental outcomes, ranging from improvements in all four environmental indicators to increases in all four. The guideline-concordant basket increased water use and eutrophication while producing little change in greenhouse gas emissions and land use. The food-group decomposition showed that these aggregate outcomes reflected opposing contributions from a small number of foods. Reducing UPF consumption can generate substantial health and economic benefits, but environmental co-benefits are not automatic and depend on the dietary patterns that replace UPFs.

Sub-Saharan African (SSA) cities have high air and noise pollution levels, yet limited information exists on children's joint exposures at home and school locations - the two most important environments where children spend much of their time. This study characterised schoolchildren's exposure to multiple air pollutants and environmental noise and sound sources within the Accra School Health and Environment Study (ASHES). ASHES involved 1034 children aged 8-12 years from 90 public (73%) and private schools in Accra, Ghana, a major SSA city. Annual mean concentrations of fine particulate matter (PM_2.5), nitrogen dioxide (NO₂), and black carbon (BC), as well as environmental noise (L _day, L _night, L _den) and sound sources, were derived from land use regression models and linked to geocoded school and home locations for 919 children with valid data. A time-location weighted total exposure estimate was calculated for the air and noise pollution metrics. We also examined children's responses to a noise annoyance survey in relation to their noise exposure levels at home. For air pollutants, median home exposures were 33.8 μg m^-3 (PM_2.5), 55.5 μg m^-3 (NO₂), and 5.2 × 10^-5m^-1 (BC), and corresponding median school exposures were 29.9 μg m^-3, 53.5 μg m^-3, and 4.9 × 10^-5m^-1. The time location-weighted total air pollutant exposures for most children surpassed the respective World Health Organization (WHO) guideline. Similarly, median environmental noise levels (in dBA) at home (L _den = 66.3 and L _night = 54.2) and at school (L _day = 62.4) exceeded WHO thresholds for road-traffic noise and Ghana's noise standard for areas with educational facilities, respectively. Pollution levels at home and school were moderately correlated (r [PM_2.5] = 0.56; r [NO₂] = 0.33; r [L _den]= 0.47). On average, children attending public schools or living in lower income areas had higher exposures to both air and noise pollution than their private school (fee-paying) or higher-income counterparts. In contrast, nature-based sounds were more common in higher income areas. Among children exposed to L _den noise levels between 65 and 70 dBA, 35% reported being highly annoyed to road traffic noise. Schoolchildren in Accra experience air and noise pollution levels exceeding health-based guidelines and standards. Exposures are unequally distributed, highlighting environmental inequalities with implications for child health, development, and learning.

Storm Eunice was a severe windstorm that impacted Central Europe in February 2022. The meteorology and synoptic dynamics of Eunice have been studied in depth in several studies examining features of the storm such as its sting jet. The contribution of climate change to the storm dynamics and severity was examined in previous work, which found that in counterfactual weather forecasts-given an identical initial synoptic setup-climate change had measurably increased the severity of the storm. Here we move beyond meteorological attribution and quantify the role of climate change in the insured losses incurred during Eunice in, to the best of our knowledge, the first impact attribution of its kind for a European windstorm event. We combine the same counterfactual weather forecasts with three loss models, including two state-of-the-art commercial models, finding that the increases in meteorological severity do translate through to significant increases in estimated loss. We estimate a conditional increase in insured loss of nearly €2 bn between pre-industrial and present-day climates. Of particular note is the existence of several members within the forecast ensembles whose losses are far greater than what unfolded in reality. This includes one realisation, simulated in a warmer 'future' climate, in which the estimated loss could reach over 10x the realised loss during Eunice. The plausible existence of such a catastrophic loss is of considerable relevance to a wide variety of stakeholders across adaptation planning and the financial sector. We suggest that our results practically demonstrate not only the utility of counterfactual weather forecasts in quantifying impacts attributable to climate change, but also the value of academic-private partnerships in which the two sectors are able to bring different areas of expertise.

Systematic assessments of climate change adaptation are critical for monitoring progress and planning effectively, but current approaches are limited in their scope, accuracy, and relevance to local contexts. Here, we present an improved approach using coproduction to quantitively assess adaptation based on local knowledge and priorities. This is applied to locally led adaptation (LLA) to flood risk in Tamale, Ghana, to provide the first quantitative assessments of this increasingly common adaptation practice. Through a multi-year process, including community marble distribution, focus groups, and household surveys, 11 LLA solutions were assessed. Assessments were based on adaptation success criteria that mattered most to local communities and included important considerations that are commonly missing from technical assessments, including multiple risk-reduction mechanisms, equity, sustainability, and co-impacts. Community-based and behavioural LLA solutions, such as collective action and tree planting, were deemed most effective, whilst structural and technical solutions were ranked lower. By integrating these assessments into a flood risk model, we show that LLA approaches significantly reduced flood risk overall but did not address existing inequalities. Our results showcase the potential of coproduction to increase the scope and robustness of adaptation assessments and highlight practical challenges of delivering on the LLA principles in real-world settings.

Wildfires are an increasingly important source of toxic air pollutants, including carcinogenic polycyclic aromatic hydrocarbons (PAHs), with implications for human health under a changing climate. Here, we quantify the influence of fire events on PAH concentrations, chemistry, and associated incremental lifetime cancer risk (ILCR) using a global three-dimensional chemical transport model. Fires contribute up to 42% of local PAH concentrations in fire-prone regions, including Australia, sub-Saharan Africa, Siberia, and Canada, and account for approximately 4.6% of global total PAH concentrations. Fire emissions also enhance fine particulate matter (PM_2.5) levels, promoting partitioning of PAHs into the particle phase. Additionally, fires alter atmospheric oxidant levels, increasing the formation of highly toxic PAH degradation products, which contribute up to 55% of fire-sourced PAH cancer risk. As a result, fire-derived PAH mixtures are 51% more carcinogenic per unit mass than non-fire mixtures. Globally, fires contribute between 4 and 6% of the total all-source PAH ILCR, with some regions exceeding the recommended risk threshold of $1.0\times {10}^{-6}$ due solely to fire-related pollution. Sensitivity analyses indicate that even when fire emissions are dominated by less toxic lower molecular weight PAHs, fire-sourced PAHs are more toxic than anthropogenic-sourced PAHs, highlighting the critical role of atmospheric chemistry in modulating health impacts. These findings demonstrate that wildfires not only elevate PAH concentrations but also increase their per-mass toxicity through chemical transformations. With projections of increasing wildfire frequency and intensity under climate change, our results underscore the need for comprehensive monitoring, emission characterization, and mitigation strategies to address the growing public health risks of fire-related air pollution, particularly in regions frequently affected by wildfires.

Urban parks provide mental and physical health benefits by mitigating harmful environmental exposures, including heat and air pollution. Urban parks often cluster in more privileged neighborhoods. Health burdens from harmful environmental exposures are highest in less privileged ones. Using Trust for Public Land's ParkServe database of publicly accessible parks, sociodemographic data from the American Community Survey, and high-resolution satellite-imagery, we compared park size and environmental conditions by neighborhood privilege. To ascertain privilege, we calculated the combined race and income index of concentration at the extremes (ICEs) in each census tract of the 24 most populous urban areas in the United States (U.S.). We found that parks in the least privileged neighborhoods (i.e. bottom quartile of ICE) had on average 1.24 ppb higher concentrations of nitrogen dioxide (NO₂) and 1.00 μg/m^-3 higher fine particulate matter (PM_2.5) than parks in the most privileged neighborhoods (top ICE quartile). Parks in the most privileged neighborhoods were significantly larger and cooler in more than half of the included urban areas and significantly greener in over a third. Our results reveal disparities in the environmental conditions, and thus expected health benefits, between parks in the most and least privileged neighborhoods in the most populous urban areas in the U.S.

The climate crisis and mass incarceration are deeply intertwined. While climate change has intensified worldwide, incarcerated populations are disproportionately at risk of experiencing poor health related to climate change through multiple hazards including extreme heat, hurricanes, and wildfires. We detail how incarcerated individuals are at a heightened risk of experiencing multiple climate-related events, how climate change worsens the health of incarcerated individuals, and how carceral infrastructure and policies worsen these impacts. We then propose next steps including (1) further research to assess the full scope of climate-related health risks, (2) strong collaborations between researchers, policymakers, and community advocates, and (3) implementation of evidence-based policies that prioritize the well-being of incarcerated populations that span climate mitigation, climate adaptation, and decarceration measures.