Long-term exposure to ambient ozone (O3) is associated with excess respiratory mortality. Pollution emissions, demographic, and climate changes are expected to drive future ozone-related mortality. Here, we assess global mortality attributable to ozone according to an IPCC (Intergovernmental Panel on Climate Change) SSP (Shared Socioeconomic Pathway) scenario applied in CMIP6 (Coupled Model Intercomparison Project Phase 6) models, projecting a temperature increase of about 3.6°C by the end of the century. We estimated ozone-related mortality on a global scale up to 2090 following the Global Burden of Disease (GBD) 2019 approach, using bias-corrected simulations from three CMIP6 Earth System Models (ESMs) under the SSP3-7.0 emissions scenario. By comparing simulations with varying and present-day sea surface temperatures, we distinguish the trajectory of climate change in future ozone-related mortality. We also estimated the influence of demographic and ozone precursor trends alone. Finally, by applying optimal (minimum) baseline mortality rates for all countries, we investigate the potential future benefits of improved living and health-care conditions. Based on the three ESMs simulations, global ozone-related mortality by 2090 will amount to 2.79M [95% CI 0.97M–5.23M] to 3.12M [95% CI 1.11M–5.75M] per year, approximately ninefold that of the 327K [95% CI 103K–652K] deaths per year in 2000. Climate change alone may lead to an increase of ozone-related mortality in 2090 between 42K [95% CI -37K–122K] and 217K [95% CI 68K–367K] per year. Population growth and ageing are associated with an increase in global ozone-related mortality by a factor of 5·34, while the increase by ozone trends alone ranges between factors of 1.48 and 1.7. Ambient ozone pollution under the high-emissions SSP3-7.0 scenario is projected to become a significant human health risk factor. Yet, optimising living conditions and healthcare standards worldwide to the optimal ones today will help mitigate the adverse consequences associated with population growth and ageing, and ozone increases caused by pollution emissions and climate change.
D Akritidis, S Bacer, P Zanis, AK Georgoulias, S Chowdhury, LW Horowitz, V Naik, FM O’Connor, J Keeble, P Le Sager, T van Noije, P Zhou, S Turnock, JJ West, J Lelieveld, A Pozzer. Strong increase in mortality attributable to ozone pollution under a climate change and demographic scenario
Journal: Lancet Planet Health, Year: 2023, doi: submitted