On the Nonlinear Mapping of a Surface Gravity Wave Spectrum into a Sar Image Spectrum and Freak Wave Detection
نویسنده
چکیده
It is shown that the nonlinear mapping relation between a surface gravity wave spectrum and its SAR image spectrum, as derived by Hasselmann and Hasselmann [1], is not complete. The reason for this is that the velocity bunching effect is so nonlinear that effects of skewness and kurtosis are as important as the nonlinear terms already retained in the Hasselmann and Hasselmann approach. An analysis of the azimuthal cutoff may therefore reveal information on the non-gaussian statistics of the sea surface, and may indicate the enhanced occurrence of freak waves.
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