Abstract
Soil moisture is one of the key parameters of land-atmosphere interaction, which affect the seasonal and interannual variations of the global and regional water cycle considerably. To find out a long-term trend of this parameter, a Special Sensor Microwave Imager (SSM/I) algorithm is proposed in this paper by extending an Advanced Microwave Scanning Radiometer (AMSR-E) algorithm. A microwave brightness temperature which was obtained by SSM/I is calibrated to fill in gaps of models.
Although there is disadvantage to estimate soil moisture using SSM/I data, accuracy equal to AMSR-E was obtained through an algorithm validation in the Mongolia reference site of the Coordinated Enhanced Observing Period (CEOP), and a trend of this site was found out by applying the algorithm to the long-term SSM/I data.
