用闪电定位资料和雷达回波资料进行分析,即从雷达产品的4个参数与地闪频数的关系进行相关分析,分析结果表明:(1)反射率因子的回波面积大小和强回波中心的移动与闪电发生的时间、地点有很好的一致性。(2)闪电发生前最大回波顶高有明显的增大,闪电发生的位置和最大回波顶高的位置有很好的对应关系。(3)地闪频数的变化与VIL(垂直累积液态含水量)最大值的变化并不完全对应,但VIL最大值下降到25kg/m2以下时,可以考虑作为雷暴消散的一个因子。VIL大值区的移动以及VIL大值区面积的变化与地闪频数的整体变化是一致的。(4)雷达VwP产品的无数据区破坏的时间提前于闪电的发生和地闪频数的增长,其恢复滞后于闪电消失。
Based on the lightning location and radar echo data, a relative analysis on the relationship between four parameters of radar products and ground lightning frequency was conducted. The results show : ( 1 ) the echo area of reflectivity factor and the movement of strong echo center are closely consist- ent with the time and place of lightning; (2) the maximum echo top goes up rapidly before the lightning. The places of the maximum echo top correspond to the places where the lightning happens; (3) although ground lightning frequency is not associated completely with the maximum vertically integrated liquid wa- ter(VIL) value, the movement and variation of VIL larg-value area are consistent with the entire variation tendency of ground lightning frequency. The maximum VIL value less than 25 kg/m2 can be considered as a threshold value for thunderstorm dissipating; (4) when the destructing time of area devoid of VWP product data is ahead of the lightning and its frequency rise, then its recovery tends to lag behind the lightning frequency disappearance.