Variability and redistribution of heat in the Atlantic Water boundary current north of Svalbard
Renner, Angelika H. H.
Janout, Markus A.
Ingvaldsen, Randi B.
Pickart, Robert S.
Pérez-Hernández, M. Dolores
MetadataShow full item record
We quantify Atlantic Water heat loss north of Svalbard using year‐long hydrographic and current records from three moorings deployed across the Svalbard Branch of the Atlantic Water boundary current in 2012–2013. The boundary current loses annually on average 16 W m−2 during the eastward propagation along the upper continental slope. The largest vertical fluxes of >100 W m−2 occur episodically in autumn and early winter. Episodes of sea ice imported from the north in November 2012 and February 2013 coincided with large ocean‐to‐ice heat fluxes, which effectively melted the ice and sustained open water conditions in the middle of the Arctic winter. Between March and early July 2013, a persistent ice cover‐modulated air‐sea fluxes. Melting sea ice at the start of the winter initiates a cold, up to 100‐m‐deep halocline separating the ice cover from the warm Atlantic Water. Semidiurnal tides dominate the energy over the upper part of the slope. The vertical tidal structure depends on stratification and varies seasonally, with the potential to contribute to vertical fluxes with shear‐driven mixing. Further processes impacting the heat budget include lateral heat loss due to mesoscale eddies, and modest and negligible contributions of Ekman pumping and shelf break upwelling, respectively. The continental slope north of Svalbard is a key example regarding the role of ocean heat for the sea ice cover. Our study underlines the complexity of the ocean's heat budget that is sensitive to the balance between oceanic heat advection, vertical fluxes, air‐sea interaction, and the sea ice cover.
© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of Geophysical Research: Oceans 123 (2018): 6373-6391, doi:10.1029/2018JC013814.
Suggested CitationJournal of Geophysical Research: Oceans 123 (2018): 6373-6391
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivatives 4.0 International
Showing items related by title, author, creator and subject.
The Atlantic Water boundary current in the Nansen Basin : transport and mechanisms of lateral exchange Våge, Kjetil; Pickart, Robert S.; Pavlov, Vladimir; Lin, Peigen; Torres, Daniel J.; Ingvaldsen, Randi B.; Sundfjord, Arild; Proshutinsky, Andrey (John Wiley & Sons, 2016-09-22)Data from a shipboard hydrographic survey near 30°E in the Nansen Basin of the Arctic Ocean are used to investigate the structure and transport of the Atlantic Water boundary current. Two high-resolution synoptic crossings ...
Intermediate water links to Deep Western Boundary Current variability in the subtropical NW Atlantic during marine isotope stages 5 and 4 Evans, H. K.; Hall, Ian R.; Bianchi, G. G.; Oppo, Delia W. (American Geophysical Union, 2007-08-02)Records from Ocean Drilling Program Sites 1057 and 1059 (2584 m and 2985 m water depth, respectively) have been used to reconstruct the behavior of the Deep Western Boundary Current (DWBC) on the Blake Outer Ridge (BOR) ...
Spreading of Denmark Strait overflow water in the western subpolar North Atlantic : insights from eddy-resolving simulations with a passive tracer Xu, Xiaobiao; Rhines, Peter B.; Chassignet, Eric P.; Schmitz, William J. (American Meteorological Society, 2015-12)The oceanic deep circulation is shared between concentrated deep western boundary currents (DWBCs) and broader interior pathways, a process that is sensitive to seafloor topography. This study investigates the spreading ...