An updated geophysical model for WindSat observations

An accurate geophysical model is required to support calibration of a microwave imaging radiometer and retrieval of geophysical parameters. WindSat is a passive microwave imaging radiometer aboard the Coriolis satellite which was launched in January 2003. WindSat observations include dual-polarized antenna temperatures in two frequency bands (6.8 GHz and 23.8 GHz) and fully polarimetric antenna temperatures in three frequency bands (10.7 GHz, 18.7 GHz and 37.0 GHz). We have updated the Naval Research Laboratory (NRL) geophysical model for WindSat using an improved atmospheric model and by accounting for the frequency pass-band characteristics of the individual receivers. We have developed a parameterized version of the model which is used for both WindSat calibration and retrievals.