Study of Brightness Temperature and Soil Moisture Downscaling Using Airborne Passive Microwave Observations

The application of passive microwave soil moisture products is limited by the poor spatial resolution. In this study, a spatially-based regression method was tested using the PLMR(Polarimetric L-band Multibeam Radiometer) observation data acquired in the Heihe Watershed Allied Telemetry Experimental Research (HiWATER). The land surface temperature data were used as the auxiliary data to perform downscaling soil moisture and brightness temperature. The root-mean-square errors (RMSEs) of brightness temperature and soil moisture are 5.5 K and 0.021 cm3/cm3 between the calculated values and refenced values, respectively. This method provided a potential way for the downscaling of passive microwave brightness temperature and soil moisture.