Urban Heatwave Resilience and Spatial Drivers: A 20-Year Geo-Spatial Analysis in Chengdu, China

Amidst global climate change and rapid urbanization, urban heatwaves pose a severe threat to thermal environmental resilience, impacting public health and socioeconomic stability. Accurately quantifying the spatiotemporal dynamics of heatwave risks and resilience is a critical prerequisite for developing effective urban climate adaptation strategies. However, previous research is often limited by discrete station-based data and lacks standardized thermal environment metrics, failing to fully capture the complex, non-linear, and spatially non-stationary characteristics of heatwave drivers. To address these gaps, this study introduces new thermal environment indicators and employs an integrated analytical framework to analyze a 20-year high-resolution dataset for Chengdu, China. The results reveal that while land use patterns (PLAND) are the dominant factor shaping the thermal environment, the impacts of various drivers exhibit significant spatial non-stationarity; for instance, the cooling effect of green spaces diminishes in highly urbanized cores. ‘Contextual reversal’ of Aerosol Optical Depth (AOD)’s effect is shown in the result: AOD provides a cooling ‘parasol effect’ under normal conditions but can reverse its role to a warming ‘blanket effect’ during extreme heat and drought, thereby exacerbating heatwaves. Based on these findings, this study challenges ‘one-size-fits-all’ approaches and provides a robust scientific foundation for developing precise, adaptive governance strategies, such as climate-adaptive zoning, dynamic risk monitoring, and synergistic pollution-heat control policies.