基于多源数据的长江流域1982-2022年骤旱事件时空演变OA北大核心CSTPCD

A flash drought is an extreme drought phenomenon that has high suddenness and intensity and can pose a severe threat to agricultural production and ecosystems.In recent years,flash droughts have occurred frequently in the Yangtze River basin,but the temporal and spatial evolution characteristics of these flash droughts are still unclear.In this study,based on Global Land Evaporation Amsterdam Model(GLEAM),Global Land Data Assimilation System(GLDAS),and ERA5-Land data,the standardized evaporation stress ratio and changes in its value were used as identification indicators to identify flash drought events in the Yangtze River basin from 1982 to 2022,and comprehensively analyze their spatial distribution and temporal evolution characteristics.Additionally,the study examined the flash drought events in the Yangtze River basin in 2022 due to their severity and singularity.The results were as follows:① In terms of spatial distribution,the Jinsha River in the upper reaches and the large reservoirs and lakes in the middle and lower reaches of the Yangtze River basin had the highest frequency and intensity of flash drought events.(2)Temporally,the frequency,average duration,and intensity of flash drought events all showed an insignificant upward trend in the Yangtze River basin as a whole from 1982 to 2022,while some smaller areas with significant trends exhibited a notable trend reversal around 2001.(3)The Yangtze River basin was affected by extreme high temperatures and a heat wave in the summer of 2022 and suffered a large-scale flash drought event that was wide in scope,long in duration,and spatially propagated from upstream to downstream.