新疆西部“6.16”强降水过程的中尺度分析  

Mesoscale analysis on the“6.16”heavy precipitation event in the west of Xinjiang

作　　者：曾勇[1,2] 杨莲梅 ZENG Yong;YANG Lianmei(Institute of Desert and Meteorology,China Meteorological Administration,Urumqi 830002;Center for central Asia Atmosphere Science Research,Urumqi 830002)

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所,乌鲁木齐830002 [2]中亚大气科学研究中心,乌鲁木齐830002

出　　处：《暴雨灾害》2020年第1期41-51,共11页Torrential Rain and Disasters

基　　金：中国沙漠气象科学研究基金(Sqj2016016);国家自然科学基金项目(41565003,41661144024);公益性行业(气象)科研专项(GYHY201506009)。

摘　　要：利用常规观测、风云卫星、多普勒天气雷达、CMORPH卫星降水量融合资料和NCEP/NCAR(0.25°×0.25°)再分析资料,对2016年6月16—17日新疆西部一次罕见暴雨过程进行中尺度分析。结果表明:(1)该暴雨过程具有累计雨量大、暴雨强度强、局地日雨量破极值、短时强降水范围广等特点。暴雨区位于200 hPa高空西南急流出口区左侧、500 hPa偏南气流及700 hPa切变线附近。较强的CAPE和K指数对该暴雨有很好的指示意义。(2)该暴雨过程发生在低层辐合、高层辐散、低层较湿的有利背景下。强正涡度、强辐合和强上升运动不断将水汽和能量向上输送,为暴雨的产生提供有利的环境条件。(3)中亚地区中尺度雨团在发展演变过程中,逐渐形成西南-东北向带状多中心雨带,中心依次到达伊犁北部沿山地区,和原有的中尺度雨团共同作用,造成暴雨天气过程。中尺度对流云团不断产生于中亚地区,在东移过程中不断发展加强依次到达暴雨区,致使暴雨区不断产生短时强降水。(4)暴雨过程两个时段的中尺度对流系统存在明显差异,第一时段主要为孤立中尺度对流系统,造成伊宁博尔博松站成为暴雨中心并出现最强短时强降水的直接系统是风场特征明显的中γ尺度对流单体并在暴雨区维持少动。第二时段为CR达50 dBz、DVIL达4 g·m^-3,长度达70 km、宽度达10 km且呈准南北态的线状中尺度对流系统,其在向东移动过程中造成多站依次出现短时强降水天气。Based on conventional observational data,TBB data from FY-2G satellite,Doppler weather radar data,CMORPH satellite precipitation fusion data and NCEP/NCAR reanalysis data with 0.25°×0.25°spatial resolution,a rare torrential rainstorm event occurred in the west of Xinjiang from 16 to 17 June 2016 was studied.The results are as follows.(1)The heavy rain event had the features of large accumulated rainfall,strong storm intensity,local rainfall breaking record of daily precipitation,as well as broad distribution of short-time heavy precipitation.Rainstorm area was located in the left side of the export area of southwest jet at 200 hPa,nearby the southerly jet at 500 hPa and the convergence line on 700 hPa.Large values of CAPE and K indices had good instructional significance for the torrential rain.(2)The torrential rain event occurred in the favorable environment of convergence at low-level,divergence at high-level,and sufficient water vapor at low-level.Strong positive vorticity,convergence and ascent movement have continuously transported water vapor and energy upwards,providing very favorable environmental conditions for the generation of heavy rain.(3)In the process of development and evolution of mesoscale rain masses in Central Asia,a southwest-northeast multi-center rain belt was gradually formed,and the center successively arrived in the northern mountainous region of the Ili area,cooperating with the original mesoscale rain masses and resulting in heavy rain weather.The mesoscale convective cloud clusters were continuously generated in Central Asia,which continuously developed and strengthened in the process of eastward migration and arrived at the torrential rain zone in turn,which caused the continuous generation of short-term heavy precipitation in storm regions.(4)There were obvious differences in the mesoscale convective systems between the two periods of heavy rain,and the first time period was mainly isolated mesoscale convective systems.The direct system responsible for the emergence of storm cen

关 键 词：短时强降水 中尺度雨团 中尺度对流云团 线状中尺度对流系统 

分 类 号：P458.121.1[天文地球—大气科学及气象学]