The internal wave extraction from composing sea surface using SAR image

Abstract

The major goals of the variable SARs were applications in ocean wave research and wave forecasting. Two-dimensional ocean wave spectra can be derived from SIR-C/X-SAR images by inversion of the SAR imaging mechanism. But for a composite sea surface, i.e., there exist local wind-generated waves, long wave (or swell) from far fetch, internal waves and/or wave breakers, to separate very certain wave information or wave spectrum is difficult in practice. Inversion of a 2D spectrum of internal wave surface of South-China Sea is computed from SIR-C/X-SAR image data. A new inversion method is presented which estimates two dimensional wave spectra. The scheme uses prior information from ocean wave models to add missing information and to account for the fact that the SAR ocean wave imaging mechanism model is not a one to one imaging process. The scheme takes the shape of different ocean wave components as information and uses the SAR information to adjust the mean wavelengths, propagation directions and waveheights of the prior spectrum. The scheme is based on stochastic models for both the measurement error and the prior distribution. The method can separate internal wave from wind-generated waves efficiently.