Exploration of C-band /spl sigma//sup 0/ dependence on azimuth angle over Antarctic Sea and glacial ice

In previous studies, the radar backscatter measurements from polar glacial ice have demonstrated modulation in azimuth angle. Azimuthal modulation is a function of the wind induced surface characteristics of the glacial ice. In a continuing evaluation of the ERS1 C-band scatterometer as a tool for studying polar sea ice the authors evaluate the azimuthal modulation characteristics of Antarctic sea ice. Using several study regions dispersed in the Antarctic seasonal sea ice pack, the scatterometer data is evaluated for evidence of azimuthal modulation. The incidence angle dependence is estimated and removed in each study region before determining whether azimuthal modulation is present in the data. The results show that there is negligible azimuthal modulation at the scale of observation of the ERS1 C-band scatterometer.