Convective/stratiform rain behavior from TRMM

The objectives of this study are to investigate time-space variations of convective/stratiform rainfall from TRMM facility rain retrieval algorithms; study similarities and differences of convective/stratiform rainfall from TMI, PR and their combined algorithms; and explain these similarities and differences. Preliminary results show that rainfall patterns from different algorithms are consistent. Horizontal distributions of convective and stratiform rainfall and their variations are similar. Both of convective and stratiform rainfalls are important to total rainfall. Convective/stratiform and total rainfall have clearly diurnal variations. There are early morning and middle-afternoon peaks over land for summer and winter. The early morning peak over ocean exists for summer and winter, while a relative more rainfall over winter afternoon is also visible. Both convective and stratiform rainfalls have an early morning peak over ocean and land, while a dominated afternoon peak of convective rainfall exists over land for summer and winter. There is no rainfall peak activity over summer ocean. Although variations of convective/stratiform rainfall from PR and TMI related algorithms are similar, there are more contributions of stratiform rainfall from combined algorithm than PR only algorithm. Results suggest that day-1 combined algorithm (2B-31) did not resolve physics of convective rainfall very well. This is consistent with the fact that day-1 2B-31 applied only TMI 10 GHz channel information. The large foot print of this channel could not resolve small scale convections. In addition, the lack of scattering information in the day-1 2B-31 could lead to suppress high rainfall from convective rain systems.