Natural and Anthropogenic Temperature-Sensitive Emissions Amplify Ozone Pollution under Heatwaves in the Sichuan...

Climate warming intensifies heatwave-ozone (O₃) extremes, yet the role of temperature-sensitive emissions remains poorly constrained. Using WRF-CMAQ simulations, we disentangled O₃ enhancements driven by meteorological forcing and temperature-sensitive emissions from natural (biogenic VOCs, BVOCs; soil nitrogen) and anthropogenic (traffic and solvent evaporation) sources during a severe heatwave-ozone episode in the Sichuan Basin. Heatwave conditions boosted basin-wide BVOCs, transportation-evaporative, and solvent-use volatile organic compound (AVOCs) emissions by 53.6%, 26.7%, and 21.9%, respectively. The total heatwave-induced MDA8 O₃ enhancement reached 40-60 μg m^-3. While BVOCs remained dominant, temperature-enhanced AVOCs contributions surged by 68%, highlighting amplified urban anthropogenic influences. Meteorological and emission pathways showed pronounced spatial heterogeneity: meteorological stagnation dominating O₃ increases in the western basin (∼30 μg m^-3), whereas temperature-sensitive emissions added enhancements in the eastern urban regions (∼10 μg m^-3). Under future warming, temperature-sensitive emissions are projected to increase O₃ by 3.6-5.3 μg m^-3, but carbon-neutrality pathways can offset these effects, producing a net decrease of up to -18.5 μg m^-3. These findings reveal temperature-driven emissions represent a pathway that warrants greater consideration in linking climate warming to O₃ pollution, highlighting the importance of integrating climate and emission controls to mitigate future air quality risks.