The amplitude and differential threshold have been used to describe the characteristics of atmospheric electric fields in thundercloud in this paper. With these two electric field threshold and combined with radar data, a method for the first Cloud-Ground (CG) lightning forecasting in a certain range of electric field station have been put forward. First, judging electric field which reflects the charge of thundercloud whether reach amplitude threshold or differential threshold, if electric field threshold is satisfied, it is considered that the total charge of cloud is large and the probability of occurring CG lightning is also large, and then the radar data whose scan is end before the electric field threshold is detected will be judged. If radar reach the set radar threshold, the warning will occurred, otherwise judging the radar data of next scan whether reach, until warning occur or electric field indexes is canceled. The electric field data of 7 stations in summer of 2009 in Nanjing surrounding observation area were analyzed and the result showed that the probability of detection was about 80% and the average warning time was about 14min. A typical thunderstorm which moved across observation area was analyzed with the local lightning forecasting method proposed and found that it had a good warning effect. With the local lightning forecasting method, the development of thunderstorm and lightning in observation region will be presented visually and the lightning potential areas can be judged intuitively. In the meanwhile, this local lightning forecasting method can not only monitor and warn a big region, but also can monitor and warn the whole thundercloud. So it has the advantage which single-station electric field have not got.
WANG Zhenhui;XU Dongpu;ZENG Qingfeng;WANG Hao;ZHOU Shenghui;GE Fei
. Method of Lightning Forecasting Using Atmospheric Electric Field and Radar Data[J]. Science & Technology Review, 2012
, 30(14)
: 42
-48
.
DOI: 10.3981/j.issn.1000-7857.2012.14.005