Comparison of modeled and measured second azimuthal harmonics of ocean surface brightness temperatures

Second azimuthal harmonics of ocean surface brightness temperatures predicted by the second order small slope approximation (SSA) are compared to an empirical model based on WindRAD experiments performed by the Jet Propulsion Laboratory (JPL), Pasadena, CA. SSA predictions are illustrated for three differing models of the ocean surface directional spectrum, and results as a function of wind speed are shown to be in reasonable agreement with the WindRAD model at 19.35 and 37 GHz and at polar observation angles of 45/spl deg/, 55/spl deg/, and 65/spl deg/. None of the three spectral models, however, completely matches all the trends of the empirical data. A slight modification to one of the spectra is demonstrated to yield an improved agreement.