Abstract Decreases in anthropogenic aerosols will reduce fine particulate matter (PM 2.5 ); however, meteorological feedbacks alter dust emissions, modifying air quality gains. We use eight Earth System Models from the Regional Aerosol Model Intercomparison Project (RAMIP) simulations to assess African climate and air quality responses to anthropogenic aerosol emission perturbations, including meteorological feedbacks on dust emissions. By 2050, African and global emissions reductions drive the largest continent‐average PM 2.5 decrease (0.92 ± 0.17 μg m −3 ; 5% and 1.35 ± 0.50 μg m −3 ; 7%, respectively) relative to SSP3‐7.0, though regional dust increases partially offset these reductions. Anthropogenic emissions reductions in the U.S. and Europe also lower African PM 2.5 by 0.29 ± 0.32 μg m −3 (2%) due to teleconnections of Northern Hemisphere warming influencing the Intertropical Convergence Zone. Inter‐model variability in dust and total PM 2.5 reflects differences in meteorological responses and dust emission parameterizations. Meteorological responses explain 90% of dust emissions variability across regions. Aerosol‐driven climate feedbacks on dust account for up to 70% of total PM 2.5 changes in the Sahara and Namib, offsetting up to 20% of anthropogenic PM 2.5 reductions across Africa. Under 2050 global and Africa‐wide anthropogenic aerosol reductions, 96,000 (95% CI: 54,000–137,000) and 84,000 (95% CI: 43,000–125,000) PM 2.5 ‐related deaths are avoided in Africa, respectively. Dust PM 2.5 contributes an uncertain 3.4% of the avoided deaths under global reductions and has no net effect under Africa‐wide reductions. Aerosol‐driven climate feedbacks may partially offset direct air quality gains, though their continental‐scale contribution remains small and uncertain.
Amooli et al. (Mon,) studied this question.