Analysis Of Macro-physical,Micro-physical And Electrical Characteristics Of Thunderstorms In Guangdong China

Guangdong is located in low latitudes.The Tropic of Cancer runs through its middle and the elevation angle of the sun is large.The temperature is high.The air is always in an unstable state.This paper used the ground-lighting date of ADTD(Advanced TOA and Direction System)in Qingyuan,Guangdong,from June to August in 2014 to 2016.By calculating these sounding data,the parameters of different thunderstorms are obtained,and the characteristics of different intensity thunderstorm parameters are analyzed.In addition,in order to verify the conclusion of the observation of thunderstorm,a three-dimensional dynamics-electrification coupled model is uesd to analyzed a severe thundersrorm on July,17,2015 in Qingyuan to discuss the particularity of macrography,microphysics and electrification feature and the causes of formation.The results are as follows:(1)There is a good correlation between most of the convective parameters in Guangdong and the intensity of thunderstorms.With the increase of thunderstorm intensity,Showalter Index(SI)and Lifted Index(LI)is decreasing.The difference of convection effective potential energy(CAPE)between three kinds of thunderstorms is not very large.CAPE values of Seventy-five percent of thunderstorms are around 2000J/kg.While the convective inhibition energy(CIN)decreases with the increase of thunderstorm intensity.There is no obvious correlation between the Bulk Richardson Number(BRN)and the thunderstorm strength,but it is mainly concentrated between 0-1000.(2)The results indicate that this process has adequate moisture,strong updraft and high cloud height.Small particles rise rapidly with the strong updraft,and rapidly grow into large particles such as raindrops.Precipitation occurs early with strong intensity.Meanwhile,the temperature in Guangdong is higher and it is difficult to produce solid precipitation.(3)The charge structure of this thunderstorm in Guangdong is not a simplex dipole structure considered by most researchers.It transforms from tripole charge structure to dipole distribution.The middle graupel in the thunderstorm during the maturity changes into hail falling.Because the updraft can not maintain in the strong precipitation,overlap area of ice and graupel distribution is reduced.The weakening of the non-inductive collisional charging mechanism between graupel and ice makes the lower positive charge center dissipate.(4)The number of cloud-lighting is very large,while the number of ground-lighting is small.In low latitudes,troposphere has a higher height.During this process,the 0°C layer calculated by sounding data is located at 4500-5000 meters,which is in accordance with the previous actual observation.The height of the cloud can extend to about 17km.Higher charge area makes the number of cloud-lighting much larger than that of the ground-ligiting.