A nonlinear optimization algorithm for WindSat wind vector retrievals

Remote Sensing Div., Naval Res. Lab., Washington, DC, USA
IEEE Transactions on Geoscience and Remote Sensing (Impact Factor: 3.47). 04/2006; DOI: 10.1109/TGRS.2005.862504
Source: IEEE Xplore

ABSTRACT WindSat is a space-based polarimetric microwave radiometer designed to demonstrate the capability to measure the ocean surface wind vector using a radiometer. We describe a nonlinear iterative algorithm for simultaneous retrieval of sea surface temperature, columnar water vapor, columnar cloud liquid water, and the ocean surface wind vector from WindSat measurements. The algorithm uses a physically based forward model function for the WindSat brightness temperatures. Empirical corrections to the physically based model are discussed. We present evaluations of initial retrieval performance using a six-month dataset of WindSat measurements and collocated data from other satellites and a numerical weather model. We focus primarily on the application to wind vector retrievals.

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