Dynamic Downscaling Resolution Affects Hot Extreme Processes: A Case Study of 2013 Summer Extreme Hot Event Over Central and Eastern China

Abstract Understanding the complex thermal and dynamic processes during extreme climate event is important. This study investigated the 2013 extreme hot event (EHE) in central and eastern China using Weather Research and Forecasting model with resolution of 25 and 9 km (WRF25 and WRF9) respectively. Results indicated that the simulations of WRF9 outperformed WRF25 and added‐value was primarily attributed to the influence of diabatic heating, which was modulated by land‐atmosphere feedback. The more arid soil moisture limited evapotranspiration and enhanced sensible heat flux, triggering a stronger positive soil moisture‐atmosphere interaction simulated by WRF9 compared to WRF25. The higher net surface energy budget and lower cloud cover in WRF9 can heat the surface temperature even more and amplify the surface‐atmosphere temperature gradient. Notably, the strength of land‐atmosphere coupling in WRF9 was more pronounced than in WRF25. These findings have implications for the importance of model resolution in capturing the complex processes in EHE.