Study of rainstorm events characteristics and disaster risk assessment method in eastern Qinghai

This study aim to assess the risk of rainstorm disasters and enhance the ability to prevent rainstorm disasters in the densely-populated areas of eastern Qinghai. Based on the daily precipitation data of 25 national meteorological stations in eastern Qinghai , firstly, the extreme daily precipitation threshold was identified by the percentile method, the rainstorm event characteristics from 1961 to 2021 was analyzed. Then, the rainstorm disaster risk assessment model was constructed used the rainstorm disaster risk assessmen technology combined with geographic information, remote sensing and socioeconomic data, and model factor weight coefficient was caculated by entropy weight method. Finally, the actual disaster conditions of rainstorm events in 2022-2024 were used for evaluation and verification. The results are as follows. (1) From 1961 to 2021, the number of rainstorm events, daily maximum precipitation, events cumulative precipitation, and event duration in eastern Qinghai all showed an increasing trend. (2) The intensity index of rainstorm events in eastern Qinghai shows an overall increasing trend, with peaks occurring in the northeast and south. (3) The rainstorm disaster risks in eastern Qinghai is high in the northeast and low in the west. Among them, the Xining urban area, Datong County, Huangyuan County, Huangzhong District, Menyuan County, Huzhu County, Ledu District and Minhe County are high-risk areas. (4) 72.04% of the townships with disaster conditions appeared in high-risk areas, and only 13.17% appeared in low-risk areas of rainstorm disaster risks. The rainstorm disaster risk assessment model well reflected the disaster situation caused by rainstorms in eastern Qinghai.