Poor air quality contributes to a range of NCDs, including cardiovascular, respiratory and neurological, commonly resulting in hospitalisation or death. This section considers the possible risks for health of future climate-related changes in ozone and PM. The climate penalty, the degree to which global warming could affect future air quality, is better understood for ozone than for PM . This is because increases in air temperature enhance ozone formation via associated photochemical processes . The association between climate and PM is complex and moderated by a diverse range of PM components as well as formation and removal mechanisms , added to which is uncertainty about future climate-related PM sources such as wildfires  and changes in aridity . As noted in AR6 WGI Chapter 6 , future air quality will largely depend on precursor emissions, with climate change projected to have mixed effects. Because of the uncertainty in how natural processes will respond, there is low confidence in the projections of surface ozone and PM under climate change . This has implications on the levels of confidence in the projections of the health climate penalty associated with climate- induced changes in air quality .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report