内蒙古巴彦淖尔市冰雹天气云地闪电特征分析

利用闪电定位数据和雷达数据,对内蒙古自治区巴彦淖尔市地区2009~2015年37次冰雹过程的地闪特征进行分析。地闪数据的统计分析结果表明,正地闪占总地闪比例大于25%。正地闪强度较大,负地闪强度较小,地闪发生频数在降雹前一般低于3 fl/5 min,降雹后负地闪频数有明显增大。雷达和地闪定位数据的个例对比分析表明,降雹前强回波区附近以正地闪为主,地闪频数低,地闪的空间分布与对流云系的发展阶段有一定关系。地闪的空间分布可能指示云系移动方向,强回波区正地闪的时空分布可能对冰雹天气的预判有一定帮助。

Characteristics Analysis of Lightning of Hailstorms in Bayannaoer City of Inner Mongolia

Using the data of Doppler radar and lightning detection network in Inner Mongolia, the characteristics of cloud to ground (CG) lightning in 37 hail processes are analyzed in in Bayannaoer City of Inner Mongolia from 2009 to 2015. The results of statistical analysis show that the percentage of positive CG lightning to total CG lightning exceeds 25%, lightning intensity of positive CG lightning is higher than negative CG lightning. Average number of lightning per five minutes is less than 3fl/5min before hail and the number of negative CG lightning significantly increases after hail.Comparative analysis of radar and flash data shows that CG lightning frequency is low before hail and the number of positive CG lightning significantly higher than negative CG lightning. There could be a correlation between the spatial distribution of CG lightning and the development stages of convective cloud. The spatial distribution of CG lightning can portend the moving of convective cloud. The spatio temporal distribution and changing of positive CG lightning could play some reference roles in monitoring and warning hails in Bayannaoer City.