Abstract:
Soil moisture plays an important role in most hydrological processes because it is a first-order control on the partitioning of incoming precipitation and radiation. Soil moisture content largely affects microwave emission from the soil, which can be inferred from brightness temperatures (Tb) collected by microwave sensors on board a remote platform. This study focuses on the global evaluation of L-band (1.4 GHz) Tb predictions generated with the Goddard Earth Observing System (GEOS-5) relative to L-band measurements collected by the Aquarius sensor. The radiative transfer model (RTM) of this system is tuned towards L-band observations from the Soil Moisture Ocean Salinity (SMOS) mission. Tb predictions between 1 May 2012 and 1 May 2013 during non-frozen conditions are examined. Statistical analyses including coefficient of correlation, bias, and root mean squared error (RMSE) are conducted in order to assess the performance of the RTM. Preliminary results suggest the RTM does a reasonable job of reproducing measured Tb from Aquarius, but that work remains in terms of capturing the complex spatiotemporal uncertainty found in the Aquarius Tb observations.