相同大尺度环流背景下不同类型强对流天气个例分析  

Analysis of different types of severe convective weather cases under the same large-scale circulation

作　　者：翟丽萍 农孟松 屈梅芳 陈伟斌 赖珍权 

机构地区：[1]广西壮族自治区气象台,南宁530022

出　　处：《暴雨灾害》2013年第4期346-353,共8页Torrential Rain and Disasters

基　　金：中国气象局"华南西部高架对流冰雹环境场和中尺度特征分析"(CMAYBY2013-050);广西自然基金"广西暖区暴雨动力条件诊断和预报概念模型研究"(2012GXNSFAA053191)

摘　　要：利用常规观测、雷达、卫星和自动站等资料,对2013年3月23日广西一次区域性强对流天气过程中两种不同类型强对流天气现象产生的局地环境条件、触发机制及中尺度等特征进行了对比分析。结果表明:在相同大尺度环流背景下,两种类型强对流天气(即干对流型和混合对流型)在大气层结、湿层厚度、对流有效位能(CAPE值)和垂直风切变等局地环境上存在一定差异;其触发机制不同,广西西部干对流由位于地面锋前暖区的辐合线触发,而北部混合型强对流则由地面锋面触发;雷达和卫星图像上,两类强对流在形态、强度和移速上均存在明显差异,这些差异对广西不同类型强对流天气的监测预警具有一定的参考价值。Using conventional meteorological data, Doppler weather radar data, satellite images and observations from automatic weather stations, we analyzed two types of regional severe convective weather events （a dry convection and a mixed convection） occurred in Guangxi on 23 March 2013, focusing on their local environmental conditions, trigger mechanisms and mesoscale characteristics. The results show that un-der the same large-scale circulation, local environmental conditions of the dry convection are different from that of the mixed convection, as indicated by their different atmospheric stratification, wet thickness, convective available potential energy （CAPE） and vertical wind shear. The dry convection in western Guangxi is triggered by a convergence line located in the warm zone in front of the surface front, while the mixed convection in northern Guangxi is triggered by the surface front. In radar echo charts and satellite images, the difference in such fea-tures as shape, intensity and moving speed is evident between the two types of severe convective events, which can be certainly served as a reference for the monitoring and early warning of different types of severe convective weather phenomena in Guangxi.

关 键 词：干对流型 混合对流型 环境条件 触发机制 对比分析 

分 类 号：P458.11[天文地球—大气科学及气象学]