Eddies in the Western Arctic Ocean From Spaceborne SAR Observations Over Open Ocean and Marginal Ice Zones

The Western Arctic Ocean is a host to major ocean circulation systems, many of which generate eddies that can transport water masses and corresponding tracers over long distances from their formation sites. However, comprehensive observations of critical eddy characteristics are currently not availa...

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Bibliographic Details
Published in:Journal of Geophysical Research: Oceans
Main Authors: Kozlov, Igor E., Artamonova, Anastasia V., Manucharyan, Georgy E., Kubryakov, Arseny A.
Format: Article in Journal/Newspaper
Language:unknown
Published: American Geophysical Union 2019
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Online Access:https://doi.org/10.1029/2019JC015113
Description
Summary:The Western Arctic Ocean is a host to major ocean circulation systems, many of which generate eddies that can transport water masses and corresponding tracers over long distances from their formation sites. However, comprehensive observations of critical eddy characteristics are currently not available and are limited to spatially and temporally sparse in situ observations. Here we use high‐resolution spaceborne synthetic aperture radar measurements to detect eddies from their surface imprints in ice‐free sea surface roughness, and in sea ice patterns throughout marginal ice zones. We provide the first estimate of eddy characteristics extending over the seasonally ice‐free and marginal ice zone regions of the Western Arctic Ocean, including their locations, diameters, and monthly distribution. Using available synthetic aperture radar data, we identified over 4,000 open ocean eddies, as well as over 3,500 eddies in marginal ice zones from June to October in 2007, 2011, and 2016. Eddies range in size between 0.5 and 100 km and are frequently found over the shelf and near continental slopes but also present in the deep Canada Basin and over the Chukchi Plateau. We find that cyclonic eddies are twice more frequent compared to anticyclonic eddies at the surface, distinct from the dominating anticyclonic eddies observed at depth by in situ moorings and ice‐tethered profilers. Our study supports the notion that eddies are ubiquitous in the Western Arctic Ocean even in the presence of sea ice and emphasizes the need for improved ocean observations and modeling at eddy scales. © 2019 American Geophysical Union. Received 5 MAR 2019; Accepted 21 AUG 2019; Accepted article online 29 AUG 2019; Published online 9 SEP 2019. The analysis of eddies in this work was supported by RFBR grant 18‐35‐20078. Processing and analysis of Sentinel‐1 and ALOS‐2 Palsar‐2 data were done within RSF grant 18‐77‐00082. Part of this study was done by IEK during his visit to Woods Hole Oceanographic Institution (USA) within the Fulbright ...