The Atlantic Water boundary current in the Nansen Basin : transport and mechanisms of lateral exchange

• Published in: Journal of Geophysical Research: Oceans
• Main Authors: Våge, Kjetil, Pickart, Robert S., Pavlov, Vladimir, Lin, Peigen, Torres, Daniel J., Ingvaldsen, Randi B., Sundfjord, Arild, Proshutinsky, Andrey
• Format: Article in Journal/Newspaper
• Language: English
• Published: John Wiley & Sons 2016
• Subjects: Atlantic Water; Boundary current; Nansen Basin; Lateral exchange; Eddy; Upwelling; Arctic; Arctic Ocean; Canada; Pacific; canada basin; Spitsbergen
• Online Access: https://hdl.handle.net/1912/8577

Author Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 121 (2016): 6946–6960, doi:10.1002/2016JC011715. 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 of the current indicate that it is roughly 30 km wide and weakly middepth-intensified. Using a previously determined definition of Atlantic Water, the transport of this water mass is calculated to be 1.6 ± 0.3 Sv, which is similar to the transport of Atlantic Water in the inner branch of the West Spitsbergen Current. At the time of the survey a small anticyclonic eddy of Atlantic Water was situated just offshore of the boundary current. The data suggest that the feature was recently detached from the boundary current, and, due to compensating effects of temperature and salinity on the thermal wind shear, the maximum swirl speed was situated below the hydrographic property core. Two other similar features were detected within our study domain, suggesting that these eddies are common and represent an effective means of fluxing warm and salty water from the boundary current into the interior. An atmospheric low-pressure system transiting south of our study area resulted in southeasterly winds prior to and during the field measurements. A comparison to hydrographic data from the Pacific Water boundary current in the Canada Basin under similar atmospheric forcing suggests that upwelling was taking place during the survey. This provides a second mechanism related to cross-stream exchange of heat and salt in this region of the Nansen Basin. Arctic Ocean program at the FRAM-High North Research Centre for Climate and the Environment; Steven Grossman Family Foundation; National Science Foundation Grant Number: ...