三次不同类型强对流天气过程的闪电特征对比分析  

Comparative analysis on lightning flash activity characteristics of three different types of severe convective weather processes

作　　者：郭润霞 张文龙 王迎春[3] GUO Runxia;ZHANG Wenlong;WANG Yingchun(Lanzhou Central Meteorological Observatory,Lanzhou 730000,China;Institute of Urban Meteorology,China Meteorological Administration,Beijing 100089,China;Beijing Meteorological Bureau,Beijing 100089,China)

机构地区：[1]兰州中心气象台,甘肃兰州730000 [2]北京城市气象研究院,北京100089 [3]北京市气象局,北京100089

出　　处：《自然灾害学报》2020年第2期173-184,共12页Journal of Natural Disasters

基　　金：国家自然科学基金项目(41475051);河北省气象与生态环境重点实验室开放课题(Z-1501)。

摘　　要：本文利用VLF/LF三维闪电监测定位资料,结合雷达及加密地面自动站等资料,详细对比分析了北京地区三次不同类型强对流天气过程的闪电活动特征,结果表明:(1)冰雹过程中闪电活动与雷达回波的对应性最好,随强回波区的移动而移动;雷暴大风过程中闪电活动与雷达强回波的对应性较差,闪电频数少且比较分散;对流性暴雨过程中,当块状回波刚进入北京范围时,闪电活动与雷达回波基本对应并且闪电密度很大,之后闪电频数减少且分布分散,但在回波发展加强形成55dBZ的线状回波后,闪电活动又增强且分布在线状回波的前部。(2)在冰雹、雷暴大风、对流性暴雨发生期间,闪电活动强烈,闪电频数从大到小依次为对流性暴雨过程、冰雹过程、雷暴大风过程;在冰雹过程中,云闪所占比例不断增大,至降雹结束后云闪数超过地闪数;雷暴大风过程中始终都是云闪活动占主要地位;对流性暴雨过程中始终是地闪尤其是负地闪活动占主要地位,但随着回波强度的增强云闪比增大。(3)云闪发生的平均高度冰雹过程最大,其次为对流性暴雨和雷暴大风过程;云闪的平均雷电流强度也有同样的比较关系。Based on the lightning data of VLF/LF 3D(Very Low Frequency/Low Frequency 3 Dimensional)lightning location system combined with the data of radar and the data from intensive automatic weather stations,the characteristics of lightning activities in three different types of severe convective weather processes were analyzed.The results show:(1)In the hailstorm case,there is a good correspondence between lightning activity and radar echo,and lightning flashes move along with the strong echo.In the thunderstorm gale case,the correspondence between lightning activity and strong echo is not very well,and the lightning flashes have lower frequency and are dispersed.In the case of convective torrential rain,when the block echo enters the northwest of Beijing,the lightning activity basically corresponds to the radar echo and the lightning frequency is very large.Then,the lightning frequency decreases and lightning flashes spread.When the radar echo intensifies above 55dBZ and show a line shape,the frequency of lightning flashes increase and the lightning flashes mainly concentrate in the leading edge of the strong echo.(2)When the hailstorm,thunderstorm gale,or torrential rain happens,the lightning frequency is high.And the torrential rain case has the highest frequency,flowed by the hailstorm case and the thunderstorm gale case.n the hailstorm case,the proportion of IC(intracloud lightning,IC)flashes is increasing all the time,and the frequency of IC flashes exceeds that of CG(cloud-to-ground lightning,CG)flashes after the hail ends.In the thunderstorm gale case,the activity of IC is dominant throughout the convective process.In the case of torrential rain,the activity of CG,especially negative CG,is dominant,but the proportion of IC flashes become larger with the echo intensifying.(3)For the average height of IC,the hailstorm is the largest,followed by the torrential rain case and the thunderstorm gale case.The average lightning current intensity of cloud flashes has the same comparative relationship.

关 键 词：三维闪电特征 闪电频数 雷达回波 冰雹 雷暴大风 对流性暴雨 

分 类 号：P429[天文地球—大气科学及气象学] X43[环境科学与工程—灾害防治]