Meteorological and socioeconomic impacts on ozone in China: Past and future analysis

This study examines seasonal ozone (O₃) dynamics across China using a random forest model with partial dependence plots. Daily monitoring and ERA5 reanalysis data for 2015-2020, combined with CMIP6 projections to 2100, quantify the marginal effects of meteorology, socioeconomic factors, and O₃ precursors on O₃ changes. Warm-season O₃ peaks mainly north of 30°N, especially in North China, with surface temperature, relative humidity, and 500-850 hPa winds as dominant drivers. Cold-season patterns differ, reflecting widespread stagnation and reduced solar radiation. Scenario analyses under SSP 1-2.6, SSP 2-4.5, SSP 3-7.0, and SSP 5-8.5 reveal regionally heterogeneous trajectories, with some factors consistently elevating O₃ and others mitigating it depending on season and location. These results underscore the need for region-specific controls that integrate evolving climate and socioeconomic pathways and provide an evidence base for adaptive air-quality management and policy.