Airborne Dual-Polarization Observations of the Sea Surface NRCS at C-Band in High Winds

Airborne dual-polarization observations of sea surface normalized radar cross section (NRCS) were conducted over the North Atlantic during January-February 2011. Observations were made using the University of Massachusetts´ Imaging Wind and Rain Airborne Profiler radar system installed on the National Oceanic and Atmospheric Administration´s WP-3D research aircraft during several winter storm events to determine the high-wind response of the sea surface NRCS for both horizontal and vertical polarizations. During the flights, the aircraft performed several constant-roll circle maneuvers to allow collection of NRCS over a range of incidence angles. We find consistency with prior reports in the polarization ratio observed at moderate incidence angles at the winds encountered. For larger incidence angles, we observe a measurable decrease in polarization ratio with increasing wind speed.