Mesoscale Eddy Activity and Transport in the Atlantic Water Inflow Region North of Svalbard. Issue 1 (12th January 2018)

• Record Type: Journal Article
• Authors: Crews, L.; Sundfjord, A.; Albretsen, J.; Hattermann, T.
• Is Part Of: Journal of geophysical research. Volume 123:Issue 1(2018)
• Page Start: 201
• Page End: 215
• Publication Date: 2018-01-12
• Subjects: Arctic Ocean -- eddies -- transport -- halocline -- boundary current -- baroclinic instability; Oceanography -- Periodicals; 551.4605
• DOI: 10.1002/2017JC013198
• Languages: English
• ISSNs: 2169-9275

Abstract

Abstract: Mesoscale eddies are known to transport heat and biogeochemical properties from Arctic Ocean boundary currents to basin interiors. Previous hydrographic surveys and model results suggest that eddy formation may be common in the Atlantic Water (AW) inflow area north of Svalbard, but no quantitative eddy survey has yet been done for the region. Here vorticity and water property signatures are used to identify and track AW eddies in an eddy‐resolving sea ice‐ocean model. The boundary current sheds AW eddies along most of the length of the continental slope considered, from the western Yermak Plateau to 40°E, though eddies forming east of 20°E are likely more important for slope‐to‐basin transport. Eddy formation seasonality reflects seasonal stability properties of the boundary current in the eastern portion of the study domain, but on and immediately east of the Yermak Plateau enhanced eddy formation during summer merits further investigation. AW eddies tend to be anticyclonic, have radii close to the local deformation radius, and be centered in the halocline. They transport roughly 0.16 Sv of AW and, due to their warm cores, 1.0 TW away from the boundary current. These findings suggest eddies may be important for halocline ventilation in the Eurasian Basin, as has been shown for Pacific Water eddies in the Canadian Basin. Plain Language Summary: We track eddies north of Svalbard in a sea ice and ocean circulation model. These eddies move heat from the Atlantic Water boundary current into the Nansen Basin. The relationship between boundary current properties and eddy formation is also discussed. Key Points: The boundary current along the continental slope north of Svalbard sheds baroclinic eddies in an eddy‐resolving model These eddies have radii close to the local Rossby radius and temperature maxima in the halocline A mechanism for shelf‐basin exchange, the eddies move Atlantic Water and heat from the boundary current into the Eurasian Basin