Global Air Pollution Exposure and Benefits of Emissions Reductions for
Global Health
Abstract
Exposure to fine particulate matter (PM2.5) air pollution is associated
with large-scale health consequences, but the uncertainties in estimates
of PM2.5-related global premature mortality remain understudied. Using
four observation-based PM2.5 datasets and six Coupled Model
Intercomparison Project Phase 6 (CMIP6) climate models, we compare
uncertainties in current PM2.5-related mortality estimates to the
impacts of emissions reductions on global health. Although estimates of
current mortality are sensitive to the PM2.5 dataset (6.54 to 8.27
million/year using the Global Exposure Mortality Model), the projected
near-term and long-term benefits of emissions reductions for reduced
mortality are much more certain. Specifically, uncertainties in
projected avoided deaths are consistently less than half the magnitude
of uncertainties in recent mortality estimates. Under a low-emissions
scenario, avoided cumulative deaths would exceed a quarter-billion by
2100.