Ocean Eddy Signature on SAR Derived Sea Ice Drift and Vorticity

International audienceIn the Arctic Ocean, the observation of mesoscale eddies is impeded by the presence of sea ice. To address this problem, we develop a new method of ocean eddy detection based on their signature in sea ice vorticity retrieved from synthetic aperture radar (SAR) images. We examine the case of one eddy in October 2017 in the marginal ice zone of the Canadian Basin, which was sampled by mooring observations. Although the eddy could not be identified by visual inspection of the SAR images, its signature is revealed as a dipole anomaly in sea ice vorticity, which suggests that the eddy is a dipole composed of a cyclone and an anticyclone, with a horizontal scale of 80-100 km and persisted over a week. The robustness of our method will allow us to detect more eddies as more SAR observations become available in the future