Complexities in achieving air pollution-related equity goals through a net-zero transition in the United States
Reducing greenhouse gas (GHG) emissions will be accompanied by air quality improvements. The potential for these ‘co-benefits’ has been demonstrated globally and in the United States, but the impact on disparities in air pollution exposure is not well understood. Here we couple a state-level energy system model with air quality modeling to project fine-scale pollution impacts of the transition to a net zero economy. We find that achieving net zero in the United States leads to substantial reductions in PM2.5 and ozone overall, but not everywhere, and that its influence on exposure disparities is complex. The two pollutants sometimes move in opposite directions, as do the effects on future disparities across socioeconomic groups. Future meteorology plays an underappreciated role; more warming can flip a reduction in an exposure disparity to an increase in some areas, even when holding emissions constant, suggesting that the level of climate action by other nations will impact air pollution exposure inequities within the United States.
