哈密市伊吾县峡沟水库集水区汛期降水特征OA北大核心CSTPCD

Reservoirs play a pivotal role in regional economic development and societal well-being.In recent years,Xinjiang has experienced frequent extreme precipitation events,which pose significant challenges to reser-voir safety.However,research on precipitation characteristics specific to Xinjiang's reservoirs remains limited,preventing scientific guidance for water resource utilization and reservoir management.Using daily precipitation data from 1961 to 2022 and hourly precipitation data from 2009 to 2022 in the Xiagou reservoir watershed of Yiwu County,Hami City,this study analyzes long-term variations at different time scales and precipitation levels.The findings indicate following points:(1)During the rainy season from 1961 to 2022,the average precipitation in the Xiagou reservoir catchment area showed a weak increase,and the number of days with discontinuous pre-cipitation enhanced significantly.The total number of precipitation days and the maximum number of continuous precipitation days reduced evidently.Together,these trends may lead to further enhancement of the precipitation intensity in the region.(2)The rainy season is mainly characterized by light rainfall;however,over the past 62 years,the number of light and moderate rain days has declined,unlike heavy and torrential rain days.The highest proportion of rainstorms to total rainfall during the rainy season was approximately 50.0%,which was the main reason for the increase in precipitation during the rainy season in the Xiagou reservoir catchment area.(3)Daily precipitation values displayed a rising pattern as the precipitation intensity strengthened.For instance,high values for light,moderate,heavy,and torrential rain occurred in the afternoon,midday,morning,and early morning,re-spectively.Except for torrential rain,high values for other precipitation levels were predominantly observed dur-ing the daytime.The daily variation curves for the average precipitation intensity exhibit multiple peaks with re-markable variations.The relationship between cumulative precipitation frequency and amount was more closely associated with light and moderate rain than with precipitation intensity.Conversely,the relationship between av-erage precipitation intensity and cumulative precipitation amount was more closely related to heavy and torrential rain than to cumulative precipitation frequency.