A new study from the University of North Carolina Gillings School of Global Public Health estimates that future climate change, if left unaddressed, is expected to cause roughly 60,000 deaths globally in the year 2030 and 260,000 deaths in 2100 due to climate change’s effect on global air pollution.
The study, published online July 31 in Nature Climate Change, adds to growing evidence that the overall health effects of a changing climate are likely to be overwhelmingly negative. It is also the most comprehensive study to date showing the ways that climate change will affect health via air pollution, as it makes use of results from several of the world’s top climate-change modeling groups.
“As climate change affects air pollutant concentrations, it can have a significant impact on health worldwide, adding to the millions of people who die from air pollution each year, ” said Dr. Jason West, associate professor of environmental sciences and engineering at UNC. West led the research with former graduate student and first author Dr. Raquel Silva, now an Oak Ridge Institute for Science and Education (ORISE) postdoctoral research participant in the Environmental Protection Agency’s office of research and development.
Hotter temperatures speed up the chemical reactions that create air pollutants such as ozone and fine particulate matter, which impact public health. Locations that become drier also may have worse air pollution because fewer contaminants are removed by rain and there are increased fires and windblown dust. As trees respond to higher temperatures, they also will emit more organic pollutants.
Drs. West and Silva used an ensemble of several global climate models to determine the number of premature deaths that would occur due to ozone and particulate matter in 2030 and 2100. For each model, the team assessed the projected changes in ground-level air pollution that could be attributed to future climate change. They then overlaid these changes spatially on the global population, accounting for both population growth and expected changes in susceptibility to air pollution.
In aggregate, Drs. West and Silva found that climate change is expected to increase air pollution-related deaths globally and in all world regions except for Africa. Specifically, five of eight models predicted more premature deaths in 2030, and seven of nine models predicted more in 2100.
“Our finding that most models show a likely increase in deaths is the clearest signal yet that climate change will be detrimental to air quality and health,” said Dr. West. “We also collaborated with some of the world’s top climate modeling groups in the United States, United Kingdom, France, Japan and New Zealand, making this study the most comprehensive yet on the issue.”
In addition to exacerbating air pollution-related deaths, climate change is expected to affect health through changes in heat stress, access to clean water and food, severe storms and the spread of infectious diseases.
[Photo: Dr. Jason West (left) and Dr. Raquel Silva]UNC