2020年7月5—6日武汉江夏特大暴雨水汽源地和输送特征分析  

Analyses of moisture sources and transport characteristics in a rainstorm event in Jiangxia,Wuhan during July 5—6,2020

作　　者：张芳丽 李国平[2,3] 李武阶 ZHANG Fangli;LI Guoping;LI Wujie(Jiangxia Meteorological Service,Wuhan 430200;School of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610225;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing 210044;Wuhan Meteorological Observatory,Wuhan 430040)

机构地区：[1]武汉市江夏区气象局,武汉430200 [2]成都信息工程大学大气科学学院,成都610225 [3]气象灾害预报预警与评估省部共建协同创新中心,南京210044 [4]武汉市气象台,武汉430040

出　　处：《暴雨灾害》2022年第4期375-383,共9页Torrential Rain and Disasters

基　　金：国家自然科学基金项目(42175002,91937301,42075013);武汉市局科技项目(WH202119)。

摘　　要：基于武汉市加密站的降水量资料和ERA5再分析资料,对2020年7月5—6日发生在武汉江夏的一次特大暴雨过程的水汽通量、水汽收支进行分析,并引入拉格朗日混合单粒子轨道模型(HYSPLIT4)定量分析暴雨过程中的水汽来源以及水汽源区对降水的贡献。结果表明:(1)天气系统的有效配置和异常稳定是本次江夏特大暴雨产生和维持的主要原因。(2)特大暴雨所需水汽主要由南边界和西边界输入暴雨区,低纬度印度夏季风环流和副高外沿的偏南气流对水汽的输送和聚集是此次特大暴雨得以发生发展的必要条件,两支环流中偏南气流带来的水汽净流入是暴雨区水汽净收支的主要贡献者。(3)定量估算结果表明,水汽源地可追踪至印度洋、孟加拉湾-南海和西太平洋,对此次特大暴雨事件的水汽贡献率分别是24%、41%和34%。(4)对流层低层的水汽通道和源地发现925 hPa以南方路径为主,其水汽来源大值区为西太平洋和南海,而850 hPa则以西南路径为主,其水汽来源大值区位于印度洋和孟加拉湾。Based on the precipitation observations collected from the stations and the ERA5 analysis data,the moisture flux and budget of a rainstorm event that occurred in Jiangxia,Wuhan during the Meiyu period in 2020 were estimated.In addition,the Lagrangian hybrid single-particle orbit model(HYSPLIT4)is used to quantitatively analyze the contributions of various sources to the precipitation process during the event.The results are as follows.(1)The synoptic condition and its stability led to this rainstorm event and its maintenance.(2)The moisture was mainly transported from the South and West.It is the key for this torrential rainstorm event that the moisture was transported and concentrated through the Indian summer monsoon circulation at the lower latitude and the southerly flow surround the Western Pacific Subtropical High.In addition,the southerly inflow of moisture played an important role in the moisture budget of this rainstorm.(3)The main moisture sources of this rainstorm events were identified as the Indian Ocean,the Bay of Bengal-South China Sea,and the western Pacific,which accounted for 24%,41%,and 34%of the total moisture supply,respectively.(4)The southern flow was the major channel for the moisture transport at 925 hPa,which mainly originated from the western Pacific and the South China Sea,while the southwestern flow was the major channel for the moisture transport at 850 h Pa,which mainly originated from the Indian Ocean and the Bay of Bengal.

关 键 词：特大暴雨 水汽输送路径 水汽源区贡献率 拉格朗日模式 环流特征 

分 类 号：P426[天文地球—大气科学及气象学]