一次伴有雷暴的暴雪天气成因机理分析  

Cause analysis on a snowstorm accompanied with thunderstorm

作　　者：胡鹏[1,2] 蔡哲[2] 张永靖[2] 任健[2] 

机构地区：[1]南京大学大气科学学院,南京210023 [2]济南市气象局,济南250102

出　　处：《气象科学》2015年第2期210-215,共6页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(41475038)

摘　　要：利用常规气象观测资料、多普勒雷达资料和NCEP1°×1°再分析资料,采用针对对流发生的诊断分析方法对济南市2010年2月28日—3月1日的一次伴有雷暴的暴雪天气过程的水汽条件、不稳定能量和触发机制以及雷达回波特征进行了分析。结果表明:本次暴雪过程是受高空槽影响产生的,中低层的暖湿急流的输送为暴雪的产生提供了充足的水汽,造成暴雪和雷暴的不稳定状态包括对流不稳定和条件性对称不稳定。而锋生次级环流是触发不稳定能量释放的重要原因。多普勒雷达产品中的带状回波和强风速垂直切变反映了条件性对称不稳定的存在。云顶高度超过-40℃层,满足产生雷暴和闪电的必要条件。By using convensional observation data, Doppler radar data and NCEP 1°× 1° reanalysis data, the water vapor condition, unstable energy, triggering mechanism and radar echo characteristics of a snowstorm process accompanied with thunderstorm during 28 February -1 March,2010 in Jinan, Shan- dong province were combined to diagnostically analyze the convection process. Results show that ： （ 1 ） The snowstorm was caused by upper-level trough; warm and moist jets at 700 hPa or low level were able to provide sufficient water vapor to snowstorm region. （2） The potential convection instability and condi- tional symmetric instability caused the thunder to take place in the snowstorm. However, it was the fronto- genetical secondary circulation that initiated the convection. （3） The band echoes and strong vertical wind shear of Doppler radar products reflected the existence of conditional symmetric instability. The cloud top, higher than -40℃ level, was necessary to lightning production.

关 键 词：雷暴 暴雪 诊断分析 

分 类 号：P458.121[天文地球—大气科学及气象学]