Study The Microwave Characteristics Of Precipitation In China Using TRMM Data

The microwave characteristics in China are investigated using the TRMM data in this paper. Over 12nd:Fourteen cases from Yangtze River basin to South China were studied by use of the SI (Scattering Index) algorithm. The result shows:1) SI precipitation threshold is different for different precipitation cases, which indicate the increasing tendency when the precipitation area increases and while the top Tb at 85.5 GHz decreases.2) Because the SI mainly reflect the information of ice layer above the precipitation , SI >= 60K is a good index of strong convective precipitation.3) The retrieved rain rate using SI indicate the rain regions and the precipitation center well, but it seems to underestimate the rain rate at precipitation center.Over ocean:The structure of typhoon and the relation between rain rate and Tb of all the TMI channels are investigated using the TRMM data, Based on which three channels are composed to reflect the rain rate well. Result shows:2) The composed Tb make virtue of the three channels, and it get over the saturation of 19.35 and 37.0 GHz to strong rain and the low sensibility of 10.65 GHz to light rain to some extent.