Improved algorithm of retrieving oceanic surface wind speed based on a stratified media model at high sea states

Consider the effect of spray droplets and foams on the radar altimeter, an improved algorithm of retrieving oceanic surface wind speed is proposed in this study. Firstly, a four-layer medium model is established in order to simulate accurately the air–sea interface. Secondly, the microwave reflectivity of the established model is computed at 13.5 GHz. The computed results show that the effect of spray droplets and foams plays an important role in the reflectivity of the air–sea surface and causes it to decline from 0.6 to 0.23. Thirdly, the computed results are applied to retrieve the sea surface wind speed and an improved algorithm of retrieving wind speed is proposed. At low wind speeds, the improved algorithm is in good agreements with those reported results, and at high wind speeds is also in good agreements with some empirical algorithms presented by Brown, Young and so on. Finally, the improved algorithm can improve the sea surface wind speed retrieval more effectively and also is closer to the actual situation of the sea surface than those algorithms based on the three-layer medium model.