Further numerical studies of backscattering from time evolving non-linear sea surfaces

Previous studies have demonstrated that the West et al. (1987) model for non-linear hydrodynamic evolution of a sea surface realization produces significant features in calculated L-band backscattered Dopper spectra compared to a linear sea surface evolution model. Previous comparisons, however, were limited to a maximum wind speed of 2 m/s due to failure of the West et al. algorithm when steep short-wave features formed in the surface. In this paper, L-band Doppler spectra with the West et al. model are reported for wind speeds up to 4 m/s through the use of a suppression filter to reduce steep short-wave features. Results again show significant effects on Doppler spectra, including a strong polarization sensitivity at 80° observation angle.