Evolutionary Characteristics of Lightning and Radar Echo Structure in Thunderstorms Based on the TRMM satellite

Abstract. Based on the 16-years Tropical Rainfall Measuring Mission (TRMM) satellite observational data, the convective characteristics of thunderstorms over different topographic regions, as well as their radar echo structural and lightning activity, are analyzed. The results reveal that thunderstorms over the Tibetan Plateau have weak lightning frequency and small horizontal scale, but their occurrence frequency is the largest, accounting for ~ 20 % of total precipitation events, followed by 10 % over the adjacent foothills to the east and hilly land in southern China, with the lowest occurrence frequency (~ 3 %) over the ocean. The 30 dBZ echo top height is a good indicator to predict the occurrence probability of lightning in convective storm, which is more concise and intuitive than the 20 and 40 dBZ echo top heights. Integrating the ratio of convective rainfall to total rainfall and the three-dimensional radar echo structure features to identify thunderstorm life-cycle stages has been proved to be a useful method, and which can help us further explore and maximize the usage of the valuable convective event data from non-geostationary satellites. It is found that the development of dynamic process, which refers to radar echo vertical structure, precedes the lightning activity during the evolution of thunderstorms. Although both lightning activity and radar echo structure peaked at the mature stage, thunderstorms before reaching the mature stage are stronger in radar echo vertical structure while weaker in lightning activity, and vice versa after the mature stage. Even during the dissipating stage of thunderstorm, there still some lightning was observed.