First results from the SIR-C/X-SAR experiment on ocean-wave imaging in the NE Atlantic

The first results are described from an experiment in the NE Atlantic in April 1994, to study the imaging of ocean surface waves with the Shuttle Imaging Radar, SIR-C/X-SAR. Ocean waves are clearly imaged at all the simultaneously available radar frequencies and polarisations. The wavelengths and directions of the dominant swell waves show good agreement with simultaneous directional wave-buoy measurements. There is no evidence for any strong nonlinear imaging, as expected from the low range-to-velocity ratio of the imaging platform. However, some differences are seen between the simultaneous radar channels in the cases of both near-range and near-azimuth travelling waves