Application of electromagnetic models for sea near-surface wind speed retrieval from C-band SAR images

Synthetic Aperture Radar (SAR) is one of the favorite sources for sea near-surface wind speed retrieval. For this problem, wind speed is principally estimated based on the empirical (EP) models, namely CMOD functions, which are constructed by the observations from spaceborne microwave scatterometers (ERS-1/2). Little studies have mentioned the use of electromagnetic (EM) models for wind speed estimation, probably due to their complicated descriptions. However, it is reasonable to compare wind speed estimates based on the two approaches, since both of them describe the relation of radar scattering and wind field, directly for EP models and via wave surface roughness for EM models. Based on the comparisons, some ideas are proposed to improve the performance of EP and EM models.