Application of Atmospheric Electric Field Data on Lightning Prediction Around Nanjing
Zhou Jun-ch · Gaoyuan qixiang · 2013
Using the atmospheric electric field(AEF)data and ADTD lightning positioning system(LPS)data around Nanjing from June to September 2009,the characteristics of AEF during thunderstorm were analyzed.The four stages were obtained in a thunderstorm according to distance from lightning position to AEF instrument and characteristics of AEF profiles:Far-distance strokes,approaching strokes,overhead strokes and fading strokes.AEF traits in terms of amplitude,difference rate,profiles and polarity reversal were analyzed at the first and the second stages which are of high importance to lightning warning.Multiple regression equations were set up based on the characteristics discussed above and a lightning warning approach was given:(1)amplitude increasing by 21.5times as in fine weather;(2)link relative difference rate increasing by 2.6times;(3)absolute gradient of the profile reaching 0.61;(4)polarity reversal,when a stroke within 25km around the site detected,a lightning warning should be issued in emergence of the 2traits of the four above,it is likely that thunderstorms is about to come in 33.6min.