Release Date 01 August 2017

Scientists from the University of Reading have been involved in the most comprehensive study yet on climate change, air quality and premature death. 

The new study, led by the University of North Carolina (UNC) at Chapel Hill, 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 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 yet on how climate change will effect health via air pollution, since it makes use of results from several of the world's top climate change modelling groups.

Hotter temperatures speed up the chemical reactions that create air pollutants like ozone and fine particulate matter, which impact public health. Locations that get drier may also have worse air pollution because of less removal by rain, and increased fires and windblown dust. As trees respond to higher temperatures, they will also emit more organic pollutants.

Professor Bill Collins, Professor of Climate Sciences at the University of Reading and a co-author of the study, said: "Our new study shows that as well as the direct health benefits of reducing climate change, taking action on climate can also improve air pollution. Reducing the burning of fossil fuels is therefore a win-win for both climate and air quality.

"We combined complex climate models that simulate the chemistry of the atmosphere with detailed global population projections until the end of the century. We found that levels of ozone and fine particles would increase in a high climate scenario leading to roughly 60,000 extra premature deaths across the world in the year 2030 and 260,000 extra deaths in 2100. However, increased rainfall in the tropics in a warmer world was found to slightly lower pollution levels and reduce premature deaths in Africa."

"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 Jason West, who led the research at UNC-Chapel Hill with former graduate student and first author Raquel Silva.

The researchers used a variety of 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, it was found that climate change is expected to increase air pollution-related deaths globally and in all world regions except for Africa. Specifically, five out of eight models predicted there will be more premature deaths in 2030, and seven of nine models 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 West, associate professor of environmental sciences and engineering in the UNC Gillings School of Global Public Health.

"We also collaborated with some of the world's top climate modelling 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.

Full article:

J. Jason West et al (2017). Future global mortality from changes in air pollution attributable to climate change. Nature Climate Change, http://dx.doi.org/10.1038/nclimate3354