A study of SAR remote sensing of internal solitary waves in the north of the South China Sea: Ⅱ. Simulation of SAR signatures of internal solitary waves

A new model developed from the full-spectrum model of Lyzenga and Bennett (1988) is built up by us preliminarily through considering the impact of the ocean surface mixed layer turbulence on SAR remote sensing of internal solitary waves. In the partial differential equation of the action spectral density of the surface gravity-capillary waves the source function representing the contribution of the turbulence is added besides the usual source function representing the contribution of the wind. The source function is determined by applying the k-ε model and adopting the Nasmyth spectrum of oceanic turbulence (Nasmyth, 1970; Oakey, 1982; Fan, 2002) on the basis of the previous simulation results of internal tide transformation obtained in the companion paper (Fan et al.,2008). Either under relatively high wind speed, or under low wind speed, our model predicts significant large modulations of radar backscatter at all three bands (L, C and X bands) for both VV and HH polarization. These results prove that considering the impact of ocean surface mixed layer turbulence on SAR remote sensing of internal solitary waves is reasonable and appropriate for settlement of the well-known problem of contemporary radar imaging models.