一次重大雷灾事故的雷暴特征分析

Analysis of Thunderstorm Characteristics of Disaster-inducing Lightning

通过对比分析闪电定位、多普勒雷达以及地面大气电场资料,探讨2013年9月14日重大雷灾事故的致灾过程中雷灾事发地的地闪活动和雷达回波之间以及地闪活动和地面大气电场之间的关系。结果发现,当回波顶高从8 km达到13 km以及垂直积分液态含水量值由33 kg/m2跃升至48 kg/m2时,发生初闪;回波顶高的变化与地闪次数的变化呈正相关;回波强度在达53 dBz以上后,与地闪次数的变化无明显对应关系;除峰值到达时间不一致外,垂直积分液态含水量与地闪次数变化趋势基本相同;地闪次数变化与地面大气电场场强值波动频率基本一致;同一时间不同地面大气电场仪的地面大气电场场强值波动幅度大小可以表征该时刻发生的地闪与这些地面大气电场仪之间的距离远近。

Through contrastive analysis of lightning data, radar and ground atmospheric electric feld data, the lightning disaster accident in Sep. 14, 2013 was explored to find the relationship among the lightning activities and radar echo and ground atmospheric electric fieht： when the echo tops break from 8 km to 13 km and the vertical integrated liquid water content values jump from the 33 kg/m2 to 48 kg/m2 , flash oc- curred ; changes of radar echo top is related to lightning frequency ; the tendency of liquid water content changes is the same as lightning fre- quency, in addition to the peak arrival time ; there was simultaneous phenomenon of lightning frequency and ground atmospheric electric field value fluctuation frequency ; different electric field equipment of ground atmospheric electric field value fluctuate at the same time, which can show the distance between this flash and these equipments.