1981-2020年江西不同等级小时强降水的变化特征分析

Analysis on Variation Characteristics of Hourly Heavy Precipitation of Different Grades in Jiangxi Province During 1981-2020

利用江西省87个地面观测站1981—2020年逐时降水量资料,并对小时降水量≥20 mm/h的降水进行分级,对3个等级(20~30 mm/h、30~50 mm/h、≥50 mm/h)小时强降水次数的时空变化特征进行分析。结果表明:近40 a江西不同等级强降水发生频次均呈显著增加趋势,其中20~30 mm/h、30~50 mm/h等级小时强降水发生频次增加非常显著;不同等级小时强降水次数在21世纪00年代中期发生增加的突变;江西大部分观测站小时强降水次数呈增加趋势,其中江西中东部临川—丰城一带不同等级小时强降水次数增多趋势最为显著。

Using the hourly precipitation data of 87 stations in Jiangxi Province during 1981-2020,the precipitation with hourly precipitation≥20 mm/h is classified,and the temporal and spatial variation characteristics of hourly heavy precipitation in three grades(20~30 mm/h,30~50 mm/h,≥50 mm/h)are analyzed.The results show that the frequency of different levels of heavy precipitation in Jiangxi has increased significantly in recent 40 years,of which the frequency of hourly heavy precipitation of 20~30 mm/h and 30~50 mm/h has increased significantly.The hourly heavy precipitation hours of different grades has an abrupt change in the mid-2000s.The hourly heavy precipitation hours at most stations in Jiangxi shows an increasing trend,and and the increasing trend of hourly heavy precipitation hours at different levels in Linchuan Fengcheng area of central Jiangxi is especially significant.