Ocean Surface Observation by C-Band Polarimetric Weather Radar in Okinawa Island

We apply a C-band multi-parameter weather radar in the Okinawa Island to non-weather measurements. Its full-polarimetric and Doppler velocity measurement capability would be very powerful tool for observing land and ocean surface properties, if the target area is located appropriately to the radar. Located at the top of a mountain in the middle of the island, the radar has good view of its surrounding ocean. We make the radar observe ocean surfaces, in different wind conditions. The results show that the radar cross-section is larger when the wind speed is larger, and relatively smaller in the downwind side of the island, as expected. Cross-polarization components HV show similar dependency on wind conditions to HH and VV components. Measured Doppler velocities also show azimuth variation depending on the wind speed and direction.