基于拉格朗日方法的一次南疆西部特大暴雨水汽来源分析  

Water vapor source analysis of a severe torrential rain in the west of southern Xinjiang based on the Lagrangian Method

作　　者：牟欢 赵丽[3] 王旭[4] 安大维 MOU Huan;ZHAO Li;WANG Xu;AN Dawei(Meteorological Observatory of Xinjiang Uygur Autonomous Region,Urumqi 830002,China;Center for Central Asia Atmosphere Science Research,Urumqi 830002,China;Xinjiang Information Engineering School,Urumqi 830013,China;Weather Modification Office of Xinjiang Uygur Autonomous Region,Urumqi 830002,China)

机构地区：[1]新疆维吾尔自治区气象台,新疆乌鲁木齐830002 [2]中亚大气科学研究中心,新疆乌鲁木齐830002 [3]新疆信息工程学校,新疆乌鲁木齐830013 [4]新疆维吾尔自治区人工影响天气办公室,新疆乌鲁木齐830002

出　　处：《冰川冻土》2021年第4期1157-1165,共9页Journal of Glaciology and Geocryology

基　　金：新疆自治区气象局中亚大气科学研究基金项目(CAAS201910);国家自然科学基金项目(41965002)资助。

摘　　要：利用新疆自动气象站资料、NCEP/NCAR再分析资料、GDAS数据,基于拉格朗日方法的气流轨迹模式(HYSPLITv4.9),对2018年5月16—22日南疆西部特大暴雨过程的水汽源地和输送路径进行了分析。此次HYSPLIT后向轨迹模拟结果表明,暴雨水汽源于巴伦支海、喀拉海、挪威海和地中海,两地的水汽先分别沿西北气流和偏西气流向下游地区输送。水汽轨迹在哈萨克丘陵汇聚后进入北疆,再绕过天山东侧到达罗布泊地区后随低层的偏东急流抵达暴雨区上空。虽然从巴伦支海、喀拉海、挪威海出发的水汽轨迹略多于地中海,但两地的水汽贡献率分别占62%和38%。因此,巴伦支海、喀拉海、挪威海的水汽对于此次暴雨起到明显的增强作用。另外,后向轨迹模拟结果中并未出现从孟加拉湾出发的低层东方路径水汽,说明该区域的水汽并不是构成南疆西部暴雨水汽的必要条件。北极挪威海、巴伦支海、喀拉海地区海表温度异常偏高,有利于水汽源地蒸发增强和上升气流背景场的形成,北极海域的温度异常对于区域气候变化有很好的指示意义。By using the data from automatic weather stations in Xinjiang,the NCEP/NCAR reanalysis data,GDAS data and the airflow trajectory model based on the Lagrangian Method(HYSPLITv4.9),the water vapor sources and moisture transport paths of a severe torrential in the western of southern Xinjiang from May 16 to 22,2018 were analyzed.The results of HYSPLIT backward trajectories simulation showed that the severe tor⁃rential water vapor originates from the Barents Sea,the Kara Sea,the Norway Sea and the Mediterranean Sea,and the water vapor in the two regions first transported to the downstream along the northwest stream and the western stream,respectively.After converging in the Kazakh Hills,the water vapor trajectories entered the northern Xinjiang,then bypassed the eastern side of the Tianshan Mountains to reach the Lop Nur,and then reached the upper part of the severe torrential area with the lower level easterly jet.Although the water vapor tra⁃jectories from the Barents Sea,the Kara Sea and the Norway Sea were slightly more than those in the Mediterra⁃nean Sea,the contribution rates of water vapor were 62%and 38%,respectively,in the two regions.Therefore,the water vapor of Barents Sea,Kara Sea and Norway Sea played an obvious role in strengthening the rainstorm.In addition,there was no low-level eastward water vapor from the Bay of Bengal in the simulation result of back⁃ward trajectories,which indicated that the water vapor in this region was not a necessary condition for the forma⁃tion of severe torrential water vapor in the western part of southern Xinjiang.It was found that the sea surface temperature anomalies in the Barents Sea,the Kara Sea,the Norway Sea of the Arctic were high,which basical⁃ly coincide with the moisture source regions of the severe torrential.The results indicated that the anomalously high sea surface temperature in the Arctic was conducive to enhanced evaporation from the water vapor source and the formation of an updraft background field,and that the temperature anomalies in the

关 键 词：南疆 特大暴雨 拉格朗日方法 水汽轨迹 水汽贡献 

分 类 号：P458.121.1[天文地球—大气科学及气象学]