大气电场资料在雷电预警中应用

通过分析浙江省嵊县地区2007年6-10月12次强雷暴过程的电场观测资料,并结合该省闪电定位资料,发现当雷暴云移近电场仪测站时,在测站的防护区内（距测站10 km半径范围内）,闪电发生前的电场会出现快变抖动现象,并且快变抖动和闪电的发生具有0-1化对应关系,即当有电场的快变抖动出现并且在一定时间内电场值数次达到一定阈值时,电场值会随着时间增加而达到防护区内闪电出现的强度,很少有出现电场快变抖动而没有产生闪电的情况,利用多元回归技术提出雷电预警方法,将12次雷暴过程数据作为预报资料,得出预报方程及电场最佳预警参数。分析结果表明,当闪电集中发生在距电场仪10-15 km范围内,并达到电场仪预警条件时,为最佳预警时间,预警准确率达到73%。

Application of Atmospheric Electric Field Data in Lightning Warning

Through the analysis of 12 typical thunderstorm processes around Shengxian County of Zhejiang Province recorded by the atmospheric electric field instrument from June to October 2007, in combination with the data recorded by lightning position finders, it is found that when thunderstorm clouds approach the station with an electric field instrument, there will occur the phenomenon of fast changing dither before the occurrence of lightning within the protection range of the station (10 km around the station), which has the 0 1 relationship with lightning. That is, when the fast changing dither in the electric field appears and the strength of the electric field reaches a certain threshold several times in a period of time, the electric field strength will increase to achieve the intensity necessary for the appearance of lightning within the protection range, and there is little circumstances that the appearance of fast changing dither is not accompanied by the appearance of lightning. The forecast equation and most appropriate electric field parameters are given, and the method of thunderstorm warning is presented with the multivariate regression method. The results show that it is the best time to make warning when lightning strokes are concentrated within a range of 10 to 15 km around the atmospheric electric field instrument if the conditions of warning for the electric field instrument are satisfied, with the accuracy being up to about 73%.