Invited Perspective: Most Affected by Climate Change; Least Studied

Each country that is a signatory to the Paris Agreement under the United Nations Framework Convention on Climate Change (UNFCCC) produces a nationally determined contribution (NDC), outlining national plans for mitigating and adapting to climate change. The NDCs of low- and middle-income countries (LMICs) have greater coverage of the health risks of and responses to climate change, in terms of risks, adaptation, mitigation, co-benefits, and trade-offs, whereas higher-income countries tend to focus on energy, the economy, and related sectors (Dasandi et al. 2021). This difference reflects the expectation that the largest health risks of climate change will occur in LMICs, where rising ambient temperatures, changing precipitation patterns, and rising sea levels are increasingly affecting air, water, and food systems. Such changes will affect the geographic and seasonal patterns of major causes of morbidity and mortality—particularly undernutrition, diarrheal diseases, malaria, dengue, and injuries—and will disproportionately affect the most vulnerable population groups, such as the lowest-income families, older individuals, pregnant women, and neonates (Smith et al. 2014; Watts et al. 2015). The timeliness and effectiveness of adaptation and mitigation efforts will determine the extent of increase in risks with additional climate change (Ebi and Hess 2020). There is a critical need for more evidence on effective locally led adaptation and mitigation interventions

INFECTIOUS DISEASE, DEVELOPMENT, AND CLIMATE CHANGE: A SCENARIO ANALYSIS

We study the effects of development and climate change on infectious disease in Sub-Saharan Africa. Infant mortality and infectious disease are close related, but there are better data for the former. In an international cross-section, per capita income, literacy, and absolute poverty significantly affect infant mortality. We use scenarios of these three determinants, and of climate change to project the future incidence of malaria, assuming it to change proportionally to infant mortality. Malaria deaths will first increase, because of population growth and climate change, but then fall, because of development. This pattern is robust to the choice of scenario, parameters, and starting conditions; and it holds for diarrhoea, schistosomiasis, and dengue fever as well. However, the time and level of the mortality peak is very sensitive to assumptions. Climate change is important in the medium term, but dominated in the long term by development. As climate can only be changed with a substantial delay, development is the preferred strategy to reduced infectious diseases, even if that is exacerbated by climate change.Development, infectious disease, climate change, Sub-Saharan Africa, malaria

An approach for assessing human health vulnerability and public health interventions to adapt to climate change.

Assessments of the potential human health impacts of climate change are needed to inform the development of adaptation strategies, policies, and measures to lessen projected adverse impacts. We developed methods for country-level assessments to help policy makers make evidence-based decisions to increase resilience to current and future climates, and to provide information for national communications to the United Nations Framework Convention on Climate Change. The steps in an assessment should include the following: a) determine the scope of the assessment; b) describe the current distribution and burden of climate-sensitive health determinants and outcomes; c) identify and describe current strategies, policies, and measures designed to reduce the burden of climate-sensitive health determinants and outcomes; d) review the health implications of the potential impacts of climate variability and change in other sectors; e) estimate the future potential health impacts using scenarios of future changes in climate, socioeconomic, and other factors; f) synthesize the results; and g) identify additional adaptation policies and measures to reduce potential negative health impacts. Key issues for ensuring that an assessment is informative, timely, and useful include stakeholder involvement, an adequate management structure, and a communication strategy

Commonly used indices disagree about the effect of moisture on heat stress

Irrigation and urban greening can mitigate extreme temperatures and reduce adverse health impacts from heat. However, some recent studies suggest these interventions could actually exacerbate heat stress by increasing humidity. These studies use different heat stress indices (HSIs), hindering intercomparisons of the relative roles of temperature and humidity. Our method uses calculus of variations to compare the sensitivity of HSIs to temperature and humidity, independent of HSI units. We explain the properties of different HSIs and identify conditions under which they disagree. We highlight recent studies where the use of different HSIs could have led to opposite conclusions. Our findings have significant implications for the evaluation of irrigation and urban greening as adaptive responses to overheating and climate adaptation measures in general. We urge researchers to be critical in their choice of HSIs, especially in relation to health outcomes; our method provides a useful tool for making informed comparisons

Climate Change and Health on the U.S. Gulf Coast: Public Health Adaptation is Needed to Address Future Risks

The impacts of climate change on human health have been documented globally and in the United States. Numerous studies project greater morbidity and mortality as a result of extreme weather events and other climate-sensitive hazards. Public health impacts on the U.S. Gulf Coast may be severe as the region is expected to experience increases in extreme temperatures, sea level rise, and possibly fewer but more intense hurricanes. Through myriad pathways, climate change is likely to make the Gulf Coast less hospitable and more dangerous for its residents, and may prompt substantial migration from and into the region. Public health impacts may be further exacerbated by the concentration of people and infrastructure, as well as the region’s coastal geography. Vulnerable populations, including the very young, elderly, and socioeconomically disadvantaged may face particularly high threats to their health and well-being. This paper provides an overview of potential public health impacts of climate variability and change on the Gulf Coast, with a focus on the region’s unique vulnerabilities, and outlines recommendations for improving the region’s ability to minimize the impacts of climate-sensitive hazards. Public health adaptation aimed at improving individual, public health system, and infrastructure resilience is urgently needed to meet the challenges climate change may pose to the Gulf Coast in the coming decades