Analysis Of The Relationship Of Charge Structure, Meteorologic Parameter And Lightning In Thunderstorm Using Satellite Image And Radar Data

This paper mainly studies thunderstorm electrification mechanisms and charge structures, analyzes the relationship of the ground electric fields underneath thunderstorm, meteorological parameter and charging of thunderstorm, discusses the relationship of lightning, radar data and satellite image. The results can provide the reference for lightning inspection and forecasting.This paper includes three parts:Firstly, noninductive mechanisms is very important in many mechanisms of thunderstorm, and the graupel-ice mechanism is the only one that is capable of causing clouds to become electrified enough to be thunderstorm. The relation of liquid water content, the radius of particles, the velocity of particle targets and the charge is direct proportion according to empirical formula. After rimed graupel colliding with ice particles, positive and negative charges separate, the charge structure of thunderstorm presents a dipole, a tripolar or more vertically stacked charges. The charge of thunderstorm is bigger, the intensity of electric field is stronger in the thunderstorm and on the ground. The altitude of reverse temperature layer influences the altitude of charges, and the intensity of electric field on the ground has a strong relationship with the center positions. The lower center position of the positive and the negative charge will lead to stronger induced negative electric field;After the plume appearing, the charge structure tilts to one side, and positive charges mainly distribute in plume, positive and negative electric field underneath thunderstorm enlarge, being advantageous to positive and negative cloud-to-ground lightning take place. When the cloud-to-ground lightning happens, the negative cloud-to-ground lightning flashes take place firstly and consume some negative charges, then the positive ones will distribute in the plume.Secondly, the development of thunderstorm correlates with thermal instability.Based on sounding data and lightning data in Lanzhou in 2004, the relation between meteorological parameter and lightning activity is analyzed in this paper. The results indicate that the correlation of the convective available potential energy, air-mass index, combined index, vertical wind shear and lightning activity are good;At the same time, the altitude of reverse temperature layer play important role in lightning activity;And the peak current of lightning correlate with the vertical wind shear.Finally, by using lightning location system data, radar data and satellite data in three severe convective weather process in Gansu in 2004, the relations of cloud-to-ground lightning, radar echo and satellite image are analyzed. The results show that through analyzing lightning data and satellite image, the positive cloud-to-ground lightning mainly occur in the parent body of thunderstorm, the negative ones take place in downwind;After plume appearing, the positive cloud-to-ground lightning mainly distribute in the parent body of thunderstorm, the negative ones occur in plume. Combining radar echo and lightning distribution data can know, the frequency-distribution of lightning has a better correlation with the development of the liquid water;The biggest center of lightning density does not distribute in the biggest area of radar echo, the intensivest area is not the biggest region of radar echo;the distribution of cloud-to-ground lightning has a better correlation with radar echo and satellite image. Through analyzing radar data and satellite image, it can be seen that the cloud-to-ground lightning location. These results can provide the reference for lightning inspection and forecasting.