江西大气整层可降水量特征及其与暴雨的关系  

Characterisation of total column water vapour in Jiangxi Province and its relationship with rainstorm

作　　者：郑丽君 肖安 李浙华 ZHENG Lijun;XIAO An;LI Zhehua(Shangrao Meteorological Bureau of Jiangxi Province,Shangrao 334000,Jiangxi,China;Jiangxi Meteorological Observatory,Nanchang 330096,China;Key Laboratory of Climate Change Risk and Meteorological Disaster Prevention of Jiangxi Province,Nanchang 330096,China)

机构地区：[1]江西省上饶市气象局,江西上饶334000 [2]江西省气象台,江西南昌330096 [3]气候变化风险与气象灾害防御江西省重点实验室,江西南昌330096

出　　处：《干旱气象》2024年第5期755-766,共12页Journal of Arid Meteorology

基　　金：中国气象局复盘总结专项(FPZJ2023-069);江西省气象局面上项目(JX2021M01);华东区域气象科技协同创新基金合作项目(QYHZ202317);江西省气象局科技重点项目(JX2023Z05)共同资助。

摘　　要：为提高江西暴雨预报准确性,基于1990—2022年欧洲中期天气预报中心第五代大气再分析(ERA5)资料、江西省国家气象观测站日降水资料和2023年逐时降水资料,分析江西省平均与暴雨日大气整层可降水量(Total Column Water Vapour,TCWV)分布特征,并确定了有助于预测江西区域性暴雨的TCWV阈值。结果表明:江西省暴雨日的TCWV呈现出明显的时空差异,月平均TCWV中12月、1月为20.0~36.0 mm,全年最低;7—8月可达64.0 mm以上,全年最高,主要集中在赣北和赣中的平原及丘陵地区。7—8月暴雨站点的月平均TCWV的中位数超过65.0 mm;8月最大值可达77.5 mm。暴雨期间,相关站点的TCWV在强降水前通常已达到或接近月平均值,强降水后下降至月平均值以下。暴雨日月平均TCWV值可作为预测该月江西区域性暴雨的阈值:若TCWV值接近或超过月平均值上限,极端降水发生的可能性增大。最大TCWV中心虽不完全与暴雨中心雨带位置重合,但通常位于其附近的高值区内,因此在强降水天气过程中,最大TCWV中心区域可作为预测暴雨雨带位置的重要参考。In order to improve the forecasting capability of rainstorm in Jiangxi Province,based on the fifth generation European Center for Medium Weather Forecasting(ECMWF)atmospheric Re-Analysis(ERA5)data of the global climate,the daily precipitation data of the national meteorological observation stations in Jiangxi Province from 1990 to 2022 and the hourly precipitation data in 2023,the av⁃erage and rainstorm day mean of total column water vapour(TCWV)in Jiangxi Province were analyzed,and threshold criteria are given for determining the TCWV that is favorable to the occurrence of regional rainstorms in Jiangxi.The results show that the TCWV on rain⁃storm day in Jiangxi Province show obvious spatial and temporal differences.The monthly mean TCWV is 20.0 to 36.0 mm in Decem⁃ber and January,the lowest in the year;it can reach 64.0 mm in July and August,the highest in the whole year,and is mainly concen⁃trated in the plains and hilly areas in northern and central Jiangxi.The median monthly mean TCWV at rainstorm sites in July and Au⁃gust exceeds 65.0 mm;the maximum value of TCWV in August could reach 77.5 mm.During rainstorm,the TCWV at the relevant sta⁃tions usually reached or approached the monthly mean before heavy precipitation,and decreased to below the monthly mean after heavy precipitation.The monthly mean TCWV value on the day of rainstorm can be used as a threshold for predicting regional rainstorm in Ji⁃angxi during that month:if the value of TCWV is close to or exceeds the upper limit of the monthly mean,the probability of the occur⁃rence of extreme precipitation in Jiangxi Province increases.The central area of the maximum TCWV does not exactly coincide with the location of the rain band at the central area of the rainstorm,but it is usually located within the high value zone near it,so the central area of the maximum TCWV can be used as an important reference for predicting the location of the rain band of the rainstorm during heavy precipitation weather.

关 键 词：大气整层可降水量 小时降水 暴雨 

分 类 号：P426.6[天文地球—大气科学及气象学]