Synthetic Aperture Radar (SAR) images are more and more widely used in ocean wind monitoring. We present a method for the estimation of wind directions from synthetic aperture radar (SAR) images of the ocean. The method is based on winds of QuikSCAT scatterometer and Typhoon Surface Wind Model (PVM, KORDI) for the region of eye wall that the wind direction does not appear as streaks in SAR images of the ocean. Within the eye wall, the wind speed reaches its maximum and the most damaging winds and intense rainfall is found. A RADARSAT-SAR image of TY RUSA acquired on August 30, 2002 at 2112 UTC seems like the center where the NRCS is quite low, but belongs to the eye wall. To retrieve wind speeds, CMOD5 was originally developed for the scatterometer aboard ERS-1 and 2 operating at VV polarization and consequently requires modification if applied to HH-polarized SAR data. However, because the Extended High mode used here has comparatively high incidence angles of 54.24° - 57.31°, the polarization ratio in a hybrid model function is supposed to be 1. The retrieved SAR wind is compared with the result of the typhoon model with a fine computing grid of 1/60 degrees. It is shown that wind structure of eye wall can be described by using SAR based on wind directions from QuikSCAT.
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