An L-band model function for the ocean-normalized radar cross section derived from PALSAR

The relationship between ocean wind vectors and L-band normalized radar cross sections (NRCS) is comprehensively examined to propose an L-band model function by using the Phased-Array L-band Synthetic Aperture Radar (PALSAR) and scatterometer wind data. Based on more than 90,000 match-ups, the L-band NRCS dependence on wind speed, incidence angle, and relative wind direction is modeled for the 0-20 m/s wind speed and 17-43o incidence angle ranges. Wind speeds are then inversely estimated from the mutch-ups and compared with the reference winds, resulting in the -0.16 m/s bias and 2.31 m/s root mean square (rms) error. Crosswind data show poor estimation, probably due to the NRCS-wind relation temporarily saturated around 10 m/s.