Spatial and Temporal Evolution of a Multi‐Cell Thunderstorm Charge Structure in Coastal Areas

Abstract

AbstractThe spatial and temporal variations of charge structure and the relationship with intensity of radar echo of a thunderstorm over low elevation, Shandong of China, have been analyzed with the radiation sources of lightning discharge three‐dimensional mapping system. The results indicate the charge structure was typical dipolar in the convective areas. The intensity of the positive charge region increased and the height of location rose with the development of thunderstorm. The negative charge region was in the area where the intensity of radar echo was more than 40 dBz and the positive charge region was in the 40 dBz radar echo area approximately. The charge structure was also inferred to be dipolar with low charge height and weak charge intensity in stratiform areas. In the dissipation stage of thunderstorm, the charge structure was ruptured for the different dissipation levels of different parts in cloud. The positive and negative charge regions sank in front of the cloud, and the height of the positive and negative charge regions had a little change in the middle part of the cloud, whereas the negative charge region attenuated. So the charge region was four layers in convective areas during dissipation stage. The above results show that the advantage charge generation mechanism often generates dipole or tripole charge structure and does not generate multipole charge structure. This paper also analyzes a negative cloud‐ to‐ground flash discharge process. Its charge structure is the same as the thunderstorm charge structure. So the thunderstorm charge structure can be illustrated by the observations of the three‐dimensional lightning mapping system.