Three summer thunderstorms in the eastern region of China were analyzed in detail using multiple data,including Doppler radar,lightning location network,TRMM(Tropical Rainfall Measuring Mission),MTSAT(Multi-Function Transport Satellite)images,NCEP(National Centers for Environmental Prediction)Reanalysis,and radiosonde.Two of the three storms were sprite-producing and the other was non-spriteproducing.The two sprite-producing storms occurred on 1–2 August and 27–28 July 2007,producing 16and one sprite,respectively.The non-sprite-producing storm occurred on 29–30 July 2007.The major objective of the study was to try to fnd possible diferences between sprite-producing and non-sprite producing storms using the multiple datasets.The results showed that the convection in the 1–2 August storm was the strongest compared with the other storms,and it produced the largest number of sprites.Precipitation ice,cloud ice and cloud water content in the convective regions in the 1–2 August storm were larger than in the other two storms,but the opposite was true in the weak convective regions.The storm microphysical properties along lines through parent CG(cloud-to-ground lightning)locations showed no special characteristics related to sprites.The flash rate evolution in the 1–2 August storm provided additional confrmation that major sprite activity coincides with a rapid decrease in the negative CG flash rate.However,the evolution curve of the CG flash rate was erratic in the sprite-producing storm on 27–28 July,which was signifcantly diferent from that in the 1–2 August storm.The average positive CG peak current in sprite-producing storms was larger than that in the non-sprite-producing one.
中高层大气瞬态发光事件(TLEs)是发生于活跃雷暴上空平流层和中间层的一类快速大气放电现象。根据光辐射的形态特征和发生位置的不同,可将已发现的TLEs归纳为4类:由电离层快速向下发展的Red Sprites(又称红色精灵,红闪);由雷暴云顶部向上发展的Blue Jets(又称蓝色喷流,蓝激流);由闪电激发的低电离层区域的圆环状放电ELVEs(Emissions of Light and VLF per-turbation due to EMP Sources,又称光辐射和EMP源引起的甚低频扰动)和由云顶向电离层快速向上发展的Gigantic Jets(又称巨大喷流)。对已有的TLEs现象学和形态特征的观测事实以及物理机制和理论研究等进行了回顾,讨论了TLEs对平流层和中间层大气以及电离层的可能影响,并提出了目前在TLEs理论方面尚未解决的问题,指出了进一步观测和理论研究的必要性。
Unusual atmospheric light emissions were observed from a station located in Shandong Province of East China. The main morphology of these events includes a bright glowing spot, which differs distinctly from any type of transient luminous events(TLEs) well recognized in literature, such as sprites, halos, elves, gigantic jets, blue jets, and blue starters. A comparison between the observations of four such light emission events and the data from lightning detection networks reveals no correlation between these events and the intense lightning activity in the adjacent area. The events reported in this paper may imply the existence of a new phenomenon with a mechanism that remains to be investigated with further observation and complementary lightning measurement.
