In the context of global warming, increasing wildfire frequency has become a critical climate research focus in North America. This study used the Community Earth System Model (CESM 1.2) to investigate the impacts of 20th-century wildfires on North American climate and hydrology. Summer is the peak wildfire season of North American, with the Gulf of Mexico and Midwestern regions most severely affected. Wildfires not only damage vegetation during the fire season but also extend their impact into non-fire periods, showing distinct seasonal variations: causing cooling in spring through increased surface albedo, and inducing surface warming in summer and autumn by suppressing vegetation transpiration. Warming near the Gulf of Mexico enhanced moisture transport and precipitation, particularly in summer and autumn. Reduced evaporation and increased Gulf of Mexico precipitation significantly altered the hydrological cycle across North America, leading to increased runoff continent-wide.

wildfire,North America,terrestrial ecosystems,hydrological cycle