Detection of the oceanic eddies signature in sea ice drift from synthetic aperture radar images in the Arctic Ocean

Speaker: 
Angelina Cassianides
Affiliation: 
IFREMER, Brest
Seminar Date: 
10. March 2020 - 11:15 - 11:45
Location: 
Lecture room, Ground Floor, NERSC

Interactions between mesoscale eddies and sea ice could potentially represent an important mechanism, via which the ocean contributes to the on-going and future sea ice retreat. In this study, Synthetic Aperture Radar (SAR) images from Sentinel-1 are used to study the potential signature of these eddies on sea ice drift. The first step is to geolocate oceanic eddies observed from Ice Tethered Profiler data and moorings data deployed over the Arctic Ocean. Then, an algorithm based on the combination of feature-tracking and pattern-matching is applied on SAR images, allowing the computation of sea ice drift. Relative vorticity equation and Okubo-Weiss parameter, commonly used in vortex cores detection from velocity derivatives, are applied on sea ice drift. With this method, for the first time, we observe an interaction between sea ice and mesoscale eddies. During several days, eddies influence the advection of sea ice. Moreover, the analysis shows also that this interaction depends strongly on the type of ice cover but also on the depth of the eddy core.