Different HH-to-VV polarisation models' performance in retrieving wind speed using Radarsat2 image mode data by CMOD5

Abstract

As we known, CMOD models were developed for C-band VV-polarized SAR images, and when CMOD family models are applicable for HH-polarized SAR images such as Radarsat2 images it is necessary to convert normalized radar cross section (NRCS) (HH-polarized) to NRCS (VV-polarized) by the HH-to-VV polarisation model. In this study, we discussed different HH-to-VV polarisation models' performance in retrieving wind speed by CMOD5 from Radarsat2 image mode data. Image data used in this paper was taken in south of china, Hainan Island. One image was taken on condition of low wind speed while another was taken on condition of moderate wind speed. After retrieving wind speed using CMOD5 model, we compared inversion results to observation results under low and moderate wind speed conditions (the observed wind speed is 3.4m/s and 8.7 m/s). In conclusion, it is shown that three polarisation models can be applicable by acceptable error standard under different conditions. This study just gives a preliminary understanding of HH-to-VV polarisation models' performance under different wind speed conditions.