Southern Ocean Ice-Covered Eddy Properties From Satellite Altimetry - INSU - Institut national des sciences de l'Univers
Article Dans Une Revue Journal of Geophysical Research. Oceans Année : 2023

Southern Ocean Ice-Covered Eddy Properties From Satellite Altimetry

Résumé

We investigate statistical properties of surface currents as well as coherent mesoscale eddies in the seasonally ice-covered Southern Ocean. Based on a recent regional Sea Level Anomaly satellite altimetry data set, we compute Eddy Kinetic Energy (EKE) and detect mesoscale eddies. EKE is about one order of magnitude higher in the northern sector of the subpolar basin and over the continental slope, as compared to the middle of the subpolar gyres. An eddy detection methodology reveals that eddies are distributed evenly in the subpolar Southern Ocean, and their amplitude follows the spatial pattern of EKE. In addition to regional circulation variations, sea ice concentration arises as an important driver of eddy properties. Eddies have low amplitude and density in the pack ice, in particular in the middle of the gyres where the background circulation is unfavorable for instabilities. In contrast, the northern part of the Marginal Ice Zone is favorable for mesoscale eddies, especially cyclonic. There, eddies are stronger and their density is higher than in any other region of the ice-covered or ice-free subpolar Southern Ocean. This region is expected to be a site of frontogenesis due to sea ice melt and upwelling generated from interactions between the wind and the sea ice. While many mesoscale eddies will fall below detection level due to the small Rossby radius at high latitudes, these results contribute to understanding the interactions between mesoscale eddies, sea ice, and the background circulation in the subpolar region.

Mots clés

Fichier principal
Vignette du fichier
JGR Oceans - 2023 - Auger - Southern Ocean Ice‐Covered Eddy Properties From Satellite Altimetry.pdf (4.61 Mo) Télécharger le fichier
Origine Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

insu-04139559 , version 1 (24-06-2023)

Licence

Identifiants

Citer

Matthis Auger, Jean-Baptiste Sallée, Andrew F. Thompson, Etienne Pauthenet, Pierre Prandi. Southern Ocean Ice-Covered Eddy Properties From Satellite Altimetry. Journal of Geophysical Research. Oceans, 2023, 128, ⟨10.1029/2022JC019363⟩. ⟨insu-04139559⟩
65 Consultations
46 Téléchargements

Altmetric

Partager

More