Preliminary study of rainfall and storm structure over Africa with TRMM precipitation radar data

Abstract

Some preliminary investigations of the precipitation and storm structure of the major climatic regions in Africa have been conducted using a 3-year data set of the Tropical Rainfall Measuring Mission Precipitation Radar (TRMM PR). There is marked seasonal dependence of dominant rainfall type over land in comparison to the South Atlantic Ocean. During the period of maximum rainfall, the convective type of precipitation at 4 km altitude is higher than that at 2 km by more than 60% in all the land surface regions. The difference is larger for the stratiform rain type. On the other hand, no significant differences were observed over the south Atlantic and Indian oceans for the two rain types. Between a height of 2 and 10 km, convective precipitation contributes more than 60% of the total rainfall over all the land regions in the periods of rainfall peak, whereas stratiform rain dominates over the south Atlantic Ocean in all seasons of the year. The results have demonstrated the unique capabilities of the TRMM precipitation radar as a tool for providing a better understanding of the hydrological processes in data sparse areas such as Africa and adjacent tropical oceans.