Numerical Simulation Of The Characteristic Of Thunderstorm In The Region Of Jilin

Studies show that the process of the thunderstorm is very complex. The accumulation of charges and the development of charge field are restricted by many factors. Using an improved 3D cloud model, we do some simulation researches on two parameters which determine the charge structure in thunderstorm. They are reverse temperature and disturbance region, respectively. In this paper a thunderstorm occurring in Jilin province of the July 3rd, 2007 is simulated too, and the development of the microphysical process,the affection of the water substance particles on the distribution of the charge structure and the development of the charge field are analyzed. The model results show that tripolar structures are produced when the electric field reaches the breakdown value, and the negative charge region locates near -10℃temperature level. The intense electric activity begins when the updraft velocity achieves -10℃--15℃temperature level. The maximal electric field appears during the updraft velocity just begins to decrease after acquiring maximal updraft velocity.The lightning location system is an effective instrument used to the exploration and the pre-alarm of the lightning, which can observed the thunder round-the-clock. The developing intensity of thunderstorm is characterized by its lightning frequency, studies show that the frequency of lightning is relative to the height of the cloud and the intensity of radar echo, and the higher the top of the cloud is, the more the frequency of the lightning is; the lightning takes place less when the top of the cloud lower than 6km;The atmospheric stratification of the Plateau storm is totally different from that of plain storm. The thunderstorm on plateau is usually instable on the whole layers, and with low instable energy. The CAPE is homogeneously distributed without instable stratification of large energy. The maximal echo intensity of the Plateau storm is smaller than that of plain storm for the equal intensity of echoes. Generally speaking, It is a strong thunderstorm on plateau when the maximal echo intensity reaches 35dBZ. The character of the Plateau storm is different from that of the thunderstorm take place in the north of China obviously.