| In this paper,the lightning location system,FY-4 CTT(Cloud Top Temperature),LMI(Lightning Mapping Imager)datas and radar datas are used to analyze the thunderstorms in Hainan and Yunnan to study the characteristics of thunderstorms and simulating the movement path of the thunderstorm center,the following main conclusions are drawn:The lightning activities are mainly distributed in kunming,qujing,chuxiong,honghe,wenshan region,northwest yunnan diqing and nujiang area have the least amount of lightning activities.These areas at low temperatures,dry air,is not conducive to the generation of strong convective weather.Most cloud to ground lightnings occurre in summer and autumn,and the monthly variation of lightning frequency shows a single peak pattern,reaching the peak in July and August.The density of negative cloud to ground lightnings are much higher than those of positive lightnings and the negative lightnings mainly concentrate in the southeast of Yunnan province.Three thunderstorms are analyzed in this paper.From the initial stage to the dissipating stage in the thunderstorms,the pulse emitter sources are located in the radar echo region above 25 dBz.The pulse emitter in the initial and dissipating stages is located in the radar echo region of 25-30 dBz,while in the vigorous thunderstorm development stage,the pulse emitter is located in the radar echo region above 45 dBz.The radar profile of lightning in each stage of the thunderstorm process is studied.Different radar echo parameters are used to identify the thunderstorm center location,which is in good agreement with the radar echo and Fengyun-4 satellite datas,and the simulated thunderstorm movement path is consistent with the real movement path.The radar echo intensity in the thunderstorm process in Yunnan Province is far lower than that in Hainan Province.The radar echo intensity is always at 20-25 dBz when the thunderstorm starts,rises to 25-30 dBz when the thunderstorm flourishes,and then drops to 20-25 dBz in the dissipating stage.The topographic relief in Yunnan Province is relatively large and radar detection attenuation is relatively large,leading to the low radar echo intensity in the process of thunderstorm in Yunnan Province.The cloud top temperature in Hainan and Yunnan shows a trend of decreasing first and then increasing.The average cloud top temperature corresponding to the radiation source in the initial stage of the thunderstorm in Hainan Province is less than 220 K,the average cloud top temperature in the vigorous development stage is about 215 K,and the average cloud top temperature in the dissipating stage is more than 230 K.The average cloud top temperature corresponding to the radiation source in the initial stage of thunderstorm in Yunnan Province is 211 K,the average cloud top temperature in the vigorous development stage is about 208 K,and the average cloud top temperature in the dispersing stage is about 222 K.Compared with Hainan Province,the cloud top temperature in Yunnan Province during the whole process of thunderstorm is lower than that in Hainan Province,and the variation range is smaller than that in Hainan Province during the thunderstorms.The same time parameters and spatial parameters are selected to find the difference between LLS and LMI.LMI and LLS measured data have good consistency,but small amount of data and data undetectable problems exist individual area.The value of RA in Hainan Province is in the range of 0.212-0.296 in the daytime,with an average of 0.258,and in the range of 0.764-0.919 at night,with an average of 0.828.The daytime RA value in Yunnan Province ranged from 0.034-0.195,with an average of 0.062.RA values at night ranged from 0.419-0.775,with an average value of 0.49.The RA value in Yunnan Province is lower than that in Hainan Province during the day and at night.In contrast,the detection efficiency of LMI in the day is lower. |
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