2019年呼和浩特一次强雷暴天气过程综合分析  

A comprehensive analysis of a severe thunderstorm process in Hohhot of 2019

作　　者：李松如[1] 石茹琳 孙豪 LI Songru;SHI Rulin;SUN Hao(Inner Mongolia Lightning Warning and Protection Center,Hohhot 010051,China;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration,Nanjing University of Information Science&Technology,Nanjing 210044,China)

机构地区：[1]内蒙古自治区雷电预警防护中心,呼和浩特010051 [2]南京信息工程大学气象灾害预报预警与评估协同创新中心/中国气象局气溶胶与云降水重点开放实验室,南京210044

出　　处：《气象科学》2021年第3期417-426,共10页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(41590873)。

摘　　要：利用NCEP再分析资料、雷达、卫星资料以及闪电定位资料对2019年7月27日呼和浩特市一次强雷暴天气过程进行了综合分析。结果表明:此次雷暴过程主要受贝加尔湖低压中心和蒙古高原高空槽东移影响;雷暴发生前,K指数和CAPE等不稳定参数均超过阈值,大气层结呈现上干冷下暖湿的不稳定形势,并且垂直方向上低空辐合、高空辐散的结构与强烈的上升气流相配合,为雷暴天气的发生提供了有利条件;在整个雷暴过程中负地闪占主导地位,但雷暴的不同发展阶段地闪分布不同,在雷暴发展及成熟阶段,负地闪数明显多于正地闪数,而在雷暴消散阶段,正地闪数大幅增加,甚至超过负地闪;闪电多分布于强回波区域,但闪电频数最高的地方不一定与强回波中心相对应;地闪的落区主要位于云顶温度低于240 K的区域,对应的云顶相态为冰相和混合相。Based on the NCEP reanalysis,radar,satellite data,and lightning data,the process of a severe thunderstorm occurred in Hohhot on 27 July 2019 was analyzed.Results show that the thunderstorm process is mainly affected by the eastward movement of the low-pressure center of Lake Baikal and the upper-level trough of the Mongolian Plateau.Before the thunderstorm,the unstable parameters such as K index and CAPE are above the thresholds,leading to the unstable atmospheric stratification as the upper dry and low moist vertical profile.Furthermore,the vertical structure of low-level convergence and high-level divergence in conjunction with the strong updrafts,which provides the favorable conditions for the thunderstorm.Negative Cloud-to-Ground(CG)lightning dominates the whole storm process,but the distribution of CG lightning varies at different stages.The negative CG lightning counts are significantly higher than the positive CG lightning counts at the developing and mature stages while the number of positive CG lightning increases dramatically,even more than negative CG lightning at the dissipating stage.Most CG lightning is distributed in the region of strong echoes,but the highest lightning frequencies do not necessarily correspond to the center of the strong echoes.The CG lightning is mainly located in regions where the cloud top temperature is colder than 240 K,in which the cloud top phase is the ice phase and mixed phase.

关 键 词：强雷暴 物理量场 地闪 雷达回波 云顶温度 

分 类 号：P446[天文地球—大气科学及气象学]