Abstract
The Precipitation Radar (PR) observes backscatterings not only from rain particles but also surface. The backscattering coefficients are influenced by surface conditions such as vegetation and soil moisture, and incident angles etc. In this study, we investigated seasonal variation at different land cover and secular trend for 10 years using backscattering coefficients derived from TRMM/PR. As a result, a clear pattern of seasonal variation was confirmed at different land cover. A strong correlation between backscattering coefficients and precipitation appears in Sahel. In Amazon, there is significant correlation lagged by 2 months. The 10 years trend analysis demonstrated an increasing trend, however the effect of the change in orbital altitude also was included in such increasing trend.
