- Lakes significantly influence local climate, yet a systematic assessment of their cooling effect across diverse regions remains limited. This study develops a multi-metric (spatial extent, magnitude, and efficiency) framework to evaluate the spatiotemporal patterns of Lake Cooling Capacity (LCC) for 265 major Chinese lakes from 1980 to 2022. Results show that Chinese lakes exert substantial cooling on summer daytime maximum temperatures, with a mean extent of 27.5 km, a magnitude of 1.03 degrees C, and an efficiency of 0.46 degrees C/10 km. LCC efficiency shows spatially asymmetric trends, intensifying on the Tibetan Plateau but weakening in the eastern plains. Random forests analysis reveals that albedo is the dominant driver of temporal variability, while depth and surrounding topography are the primary spatial controls. These findings underscore the critical role of lakes in mitigating regional heat extremes and highlight the necessity of incorporating lake-climate feedback intoLakes significantly influence local climate, yet a systematic assessment of their cooling effect across diverse regions remains limited. This study develops a multi-metric (spatial extent, magnitude, and efficiency) framework to evaluate the spatiotemporal patterns of Lake Cooling Capacity (LCC) for 265 major Chinese lakes from 1980 to 2022. Results show that Chinese lakes exert substantial cooling on summer daytime maximum temperatures, with a mean extent of 27.5 km, a magnitude of 1.03 degrees C, and an efficiency of 0.46 degrees C/10 km. LCC efficiency shows spatially asymmetric trends, intensifying on the Tibetan Plateau but weakening in the eastern plains. Random forests analysis reveals that albedo is the dominant driver of temporal variability, while depth and surrounding topography are the primary spatial controls. These findings underscore the critical role of lakes in mitigating regional heat extremes and highlight the necessity of incorporating lake-climate feedback into climate adaptation.…

