京津冀“7·21”暴雨过程的中尺度分析  

Analysis on Mesoscale System of Torrential Rain Occurring over North China on 21 July 2012

作　　者：张迎新 李宗涛[1] 姚学祥 

机构地区：[1]河北省气象台,石家庄050021 [2]河北省气象与生态环境实验室,石家庄050021 [3]北京市气象局,北京100089

出　　处：《高原气象》2015年第1期202-209,共8页Plateau Meteorology

基　　金：公益性行业(气象)专项(GYHY200906011);河北省科技计划项目(13275402D);中国气象局预报员专项(CMAYBY2013-006);中国气象局北方暴雨团队;河北省气象局暴雨创新团队项目

摘　　要：利用常规观测资料、地面加密自动站、卫星等多种观测资料和NCEP/NCAR 0.5°×0.5°再分析资料,以及雷达变分同化分析系统VDRAS的高分辨率分析场资料,对京津冀"7·21"暴雨过程的中尺度系统进行了分析。结果表明,在α中尺度雨带中镶嵌着β中尺度的雨团;α中尺度MCC后部不断有γ、β中尺度对流云团从西侧或西南侧合并补充;中尺度滤波后发现造成京津冀"7·21"暴雨的系统为低层的中尺度切变线,东移过程中加深为中尺度低涡扰动,中尺度切变或低涡位于对流层中低层(为近乎直立的正涡度柱),高层为辐散场(负涡度),但负涡度值与中低层正涡度值要小得多,说明主要是中低层的系统强;分析VDRAS资料同样发现对流层低层强辐合,存在中尺度涡度柱,其上方是中尺度反气旋,热力结构为上暖湿下冷湿。The mesoscale system of torrential rain occurring over the North China on 21 July 2012 have been investigated using conventional observation data,intensive automatic weather station observations,satellette data,NCEP / NCAR reanalysis data( 0. 5° × 0. 5°) and low-level thermal and dynamical retrieval system of 4Dvar based on Variational Doppler Radar Analysis System( VDRAS). The conclusions are draw n as follow s: Separated β-mesoscale rain cluster w ere mounted in the α-mesoscale rain band. There w ere γ or β-meso scale convective cloud occurring and merged in M CC from w estern or southw est side. The mesoscale rain band moved with mesoccale wind shear and vortex intensified in the eastw ard movement. The wind shear or vortex existed in the low and middle troposphere( almost erecting positive vorticity column),and divergence stream in upper level( negative vorticity). The same results have got from VDRAS data. Humid and cold air in the lower,but humid and w arm in the upper level.

关 键 词：暴雨 中尺度雨团 垂直结构 中尺度对流系统(MCSs) 

分 类 号：P458.121.1[天文地球—大气科学及气象学]