2013年3月19日江西省冰雹天气成因分析  

Cause analysis of a hail event occurred in Jiangxi on 19 March 2013

作　　者：金米娜[1] 陈云辉[1] 许爱华[1] 郭艳[1] 陈娟[1] 

机构地区：[1]江西省气象台,南昌330046

出　　处：《暴雨灾害》2013年第2期158-166,共9页Torrential Rain and Disasters

基　　金：公益性行业(气象)科研专项(GYHY201006002);全国强对流预报专家团队项目

摘　　要：利用常规观测资料和卫星、雷达、自动站等非常规观测资料以及NCEP再分析资料,对2013年3月19日江西省大范围冰雹天气过程形成原因进行分析。结果表明,该过程是在有利的环境条件下发生的:对流层中低层强热力不稳定和强动力不稳定为冰雹生成和增长提供了不稳定机制;暖湿边界层偏南风急流和低层西南急流以及中层"干"西南急流对热力不稳定和动力不稳定机制发展有重要贡献;适宜的0℃层和-20℃层高度有利于冰雹增长。江西北部冰雹天气是在边界层有锋面逆温的条件下发生的,为"高架雷暴"类对流,南部冰雹天气是在边界层有较强暖平流的条件下发生的,为非"高架雷暴"类对流,两类对流的边界层温度层结分布差异明显。与历史同类个例比较发现,假相当位温垂直变化不仅能表征条件不稳定发展程度,对雷雨大风类强对流天气的判断也有一定参考意义。The cause analysis of a wide range hail event occurred in Jiangxi on 19 March 2013 was performed with various data including conventional observation data,satellite images,Doppler-Radar data,observations from automatic weather stations,reanalysis data from NCEP,etc.The results indicate that the hail event occurs under favorable environmental conditions： strong thermal and dynamic instability in middle and lower troposphere provides instability mechanism for formation and growth of hail;southerly jet in warm and moist boundary layer,southwest jet in the low-level and ＂dry＂ southwest jet in the medium level have an important contribution to the development of the thermal and dynamic instability mechanism;suitable heights of 0 ℃ level and-20 ℃ level are favorable to growth of hail.The hail event occurring in the northern part of Jiangxi province under the condition of frontal inversion in boundary layer acts as＂elevated thunderstorm type＂convective weather.The hail event occurring in the southern part of Jiangxi province under the condition of stronger warm advection in boundary layer acts as＂non-elevated thunderstorm type＂convective weather.The distributions of temperature stratifications in boundary layer for the two types of convection show significant difference.Comparing with the same type of historical cases,vertical change of θse could characterize the development of conditional instability,and also,it has a certain reference for judgment of different types of severe convective weather.

关 键 词：冰雹天气 成因分析 高架雷暴 强对流类型 

分 类 号：P458.121.2[天文地球—大气科学及气象学]