A Comprehensive Analysis On Data Of The Lightning Location System And The Doppler Radar

This research is based on the data of the lightning location system and the 714CD Doppler radar in Henan province. According to analyzing the cloud-to-ground lightning data widely, we can draw some conclusions as the follow:(1) The character of lightning spatial and temporal distribution around Zhengzhou city is not homogeneous. Most of lightning happen in July and August and they can be easy to find at 6 to 7 o'clock in morning,16 to 17 o'clock in afternoon. The high frequency of lightning can be seen at 17 o'clock. There is a obvious lightning strap lies in the north of Henan province and the east side of Taihong mountain.(2) Strong dynamic instability and thermal instability, there are some reasons that can cause lightning including updraft in medium or low layer, the height between zero to -20 centigrade, the humidity in low layer while the arid stratification in medium layer, the obvious perpendicular wind shearing deformation and the distribution of cold or warm airflow.(3) The relation between the location of lightning and the intensity of radar echo in different stage of precipitation is as follows: In the forming stage of radar echo, the lightning is apt to happen in some regions where the radar echo will become stronger. In the stage of great precipitation, the location of lightning and the intensity of radar echo will be coincident. The peak value of lightning will be in advance of the peak value of radar echo intensity. When the radar echo is dying, the lightning will seldom happen in the position of radar echo intensity exceeding 40 dBz. In addition,the statistics show that the position where the intensity of radar echo exceed 50 dBz, the lightning is easy to happen.(4)The character of Doppler radar velocity image is relevant to the linghtning's activity. When the clear air echo around radar station appear convergence of large scale circulation and warm advection superposition on it, the intensive convection echo will move toward the radar station and it will develop and the lightning has the same character. It shows that it will be useful for forecaster and the service to predict the tendency of lightning activity correctly according to the character of Doppler radar image.