[Objective]Drought-flood abrupt alteration events have significant socio-economic and ecological impacts and are a frequently occurring and widespread compound event in China.Clarifying the spatiotemporal characteristics of Drought-flood ab-rupt alteration events can provide scientific evidence for regional disaster prevention and mitigation measures.[Methods]Based on meteorological observations from 1961 to 2021,daily Standardized Precipitation Evapotranspiration Index(daily-SPEI)was calculated using the Penman-Monteith method to analyze the frequency,spatial extent,and trend of Drought-flood abrupt altera-tion events across different river basins in China.[Results]The result indicate that:(1)Temporally,from 1961 to 2021,the affected area by Drought-flood abrupt alteration events in China has shown an increasing trend of 0.6％/10a with an average an-nual occurrence rate of 19.8％.(2)Spatially,these events are mainly distributed in the Huai River Basin,Yellow River Basin,Yangtze River Basin,and Songhua River Basin,with areas experiencing over 30 occurrences accounting for 63.1％,20.7％,15.0％,and 14.6％of the total basin area,respectively,and the highest frequency reaching 53 occurrences.(3)There are distinct seasonal differences in aDrought-flood abrupt alteration events in China,with the majority occurring in the summer sea-son,covering over half of China's total area with more than 5 occurrences;followed by spring and autumn,each covering less than 15％of the total area;and the fewest occurrences are in winter,with less than 5 occurrences.[Conclusion]The findings suggest an overall increasing trend in the spatial extent of Drought-flood abrupt alteration events in China,with the central and northeastern regions being hotspots for frequent occurrences.The study result provide a scientific basis for monitoring and responding to drought-flood abrupt alteration events.
关键词
复合型事件/旱涝急转事件/逐日SPEI/时空变化特征/气候变化/时空分布/长江流域/洪水
Key words
compound events/drought-flood abrupt alteration events/daily-SPEI/temporospatial characteristics/climate change/temporal and spatial distribution/Yangtze River Basin/flood
维普
万方数据