Characteristic analysis of convective systems of the Yangtze-Huaihe River Basin based on ISCCP DX data

The temporal and spatial distributions of convection systems(CSs) that influence the Yangtze-Huaihe River Basin, and the parameter characteristics of mesoscale convective systems from 1998 to 2007 were statistically analyzed by using Deep Convection Tracking Products provided by the International Satellite Cloud Climate Program(ISCCP).The results showed that these CSs are mainly concentrated in the spring and summer, mostly generated in the Yangtze-Huaihe River Basin and central and western regions of China. These CSs exhibit a zonal distribution characteristic with the center at the Yangtze-Huaih River Basin; the closer the area to the basin, the denser the CS distribution is. The number of CSs is much larger than other large scale convections. According to their origins, the CSs can be divided into 5 categories. Affected by climate conditions and topography, these CSs are significantly different from other each. Overall, the greater the horizontal scale of CSs is, the greater the life cycle, the number of convective clusters (CCs) and the cloud temperature gradient are. Among them, the average values of the horizontal scale, the life cycle and the number of CCs in MID region are the smallest. In the SE region, CSs are mainly with medium and long life history, where the average values of the horizontal scale, maximum convective ratio and the cloud temperature gradient of CSs are the largest. During the rainy season in the Yangtze-Huaihe River Basin, convective activity is frequent. The horizontal scale and life history of CSs are long, and there is a large number of CCs within CSs.