Large-Scale Carbon Removal Will Create Public Health, Economic, and Climate Trade-Offs.

Economy-wide efforts to achieve net-zero emissions offer climate and air quality-related public health benefits from reducing fossil fuel combustion. However, carbon dioxide removal (CDR) may be necessary to meet emissions targets cost-effectively, and relying on CDR would forego some air-quality benefits. Here, we systematically quantify the regional air quality and public health implications of six CDR portfolios for the U.S. using a coupled modeling approach and compare those to a no U.S. climate action scenario. While both high- and low-CDR deployment avoid about $2.5-5.8 trillion USD2020 (or 0.4-0.8% of cumulative GDP (CGDP)) in climate damages, the high-CDR pathway costs $11-13 trillion USD2020 (or 1.8-1.9% of CGDP) by 2050, whereas the low-CDR pathway costs $16-20 trillion USD2020 (or 2.6-2.9% of CGDP) due to deeper near-term fossil fuel reductions. Public health benefits reach $2.8-6.5 trillion USD2020 (or 0.5-0.9% of CGDP) under high-CDR and are $3.5-8 trillion USD2020 (0.6-1.2% of CGDP) under low-CDR, reflecting greater reductions in particulate matter and ozone exposure and preventing approximately 12,600 additional premature deaths by mid-century. However, heavy reliance on CDR technologies could generate $5-6 trillion USD2020 (∼0.8-0.9% of CGDP) in CDR revenues by 2050, exemplifying the trade-offs between public health, economy, and climate.