Summary/Abstract
To mitigate climate warming, many countries have committed to achieve carbon neutrality in the mid-21st century. In this peer-reviewed study, the authors assess the global impacts of changing greenhouse gases (GHGs), aerosols, and tropospheric ozone (O3) following a carbon neutrality pathway on climate and extreme weather events individually using the Community Earth System Model version 1 (CESM1). The study’s results suggest that, as society approaches carbon neutrality, anticipated future aerosol reductions will significantly contribute to climate warming and increase the frequency and intensity of extreme weather, and these aerosol impacts far outweigh those of GHGs and tropospheric O3 under a carbon neutral pathway. The authors claim that these findings contradict the common assumption that changing GHGs dominate the future climate changes as predicted in the middle of the road pathway. Therefore, the authors argue that substantial reductions in GHGs and tropospheric O3 are necessary to reach the 1.5 °C warming target and mitigate the harmful effects of concomitant aerosol reductions on climate and extreme weather events under carbon neutrality in the future.