四川“8·25”远距离暴雨过程诊断分析  

Analysis of the “8.25” Far Distance Torrential Rainfall in Sichuan

作　　者：穆玉娇[1] 孙羡 MU Yujiao;SUN Xian(Civil Aviation Flight University of China,Chengdu 611431,Sichuan,China)

机构地区：[1]中国民用航空飞行学院,四川成都611431

出　　处：《民航学报》2021年第2期75-78,共4页Journal of Civil Aviation

摘　　要：利用NCEP 1°×1°再分析资料和地面加密观测资料,分析四川新津机场2017年8月25日暴雨天气过程。结果表明:1)降水初期由台风“天鸽”外围气流与副热带高压将南海和孟加拉湾暖湿气流输送至新津地区,降水后期水汽输送主要依靠台风“帕卡”与副高输送南海东南暖湿气流。2)新津地区处于倒槽前部,对流层低层倒槽两侧有较强气流辐合;随着倒槽移动低层不稳定能量和水汽沿着倒槽后部爬升,加强中层对流性不稳定和水汽辐合;3)冷空气从切变线北侧侵入产生弱冷平流,触发不稳定能量释放,产生雷暴和暴雨。Based on NCEP 1°×1°reanalysis data and ground-based observation data,a torrential rainfall process at Xinjin Airport in Sichuan Province on August 25,2017 is analyzed.The results are as follows:(1)in the early stage of the torrential rainfall,typhoon“Hato”and subtropical anticyclone transported the warm and moist air of the South China Sea and the Bay of Bengal to the Xinjin area.In the late stage of the torrential rainfall,typhoon“Pakhar”and subtropical anticyclone transported the southeast warm and moist air of the South China Sea.(2)The Xinjin area was located in the front of the inverted trough accompanying typhoon“Hato”,and there was strong convergence of airflow on both sides of the inverted trough in the lower troposphere.As the inverted trough moved,the unstable energy and water vapor in the lower layer climbed up the back of the inverted trough,and the convective instability and water vapor convergence in the middle layer were strengthened.(3)Cold air invaded from the north side of the shear line and produced weak cold advection,which triggered the release of unstable energy and generated thunderstorm and rainstorm.

关 键 词：台风 远距离暴雨 冷平流 倒槽 切变线 

分 类 号：P458[天文地球—大气科学及气象学]