Global Assimilation of SMOS Brightness Temperatures to Estimate Soil Moisture and Temperature

Abstract:

The Soil Moisture Ocean Salinity (SMOS) mission has now been collecting L-band brightness temperature observations for about 4 years. It will be discussed how the coarse-scale SMOS brightness temperatures are assimilated into the Goddard Earth Observing System (GEOS-5) Catchment land surface model with a spatial ensemble Kalman filter to estimate surface and root-zone soil moisture, as well as other land surface variables. It will be shown that assimilating multi-angular SMOS brightness temperatures yields similar results as assimilating the derived (fitted) 40^o-angle brightness temperatures, which mimic the future measurements from the Soil Moisture Active Passive mission. An evaluation of the SMOS data assimilation is performed using global assimilation statistics and in situ observations at SMAP core validation sites and sparse networks across the US.