Origin and fate of the Chukchi Slope Current using a numerical model and in-situ data

• Published in: Journal of Geophysical Research: Oceans
• Main Authors: Leng, Hengling, Spall, Michael A., Pickart, Robert S., Lin, Peigen, Bai, Xuezhi
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union 2021
• Subjects: Barrow Canyon; Chukchi Borderland; East Siberian Sea; Pacific; Beaufort Sea; Chukchi; Sea ice
• Online Access: https://hdl.handle.net/1912/27527

Author Posting. © American Geophysical Union, 2021. 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 126(5), (2021): e2021JC017291, https://doi.org/10.1029/2021JC017291. A regional coupled sea ice-ocean model and mooring/shipboard measurements are used to investigate the origins, seasonality, and downstream fate of the Chukchi Slope Current (CSC). Three years (2013–2015) of model integration indicates that, in the mean, the model slope current transports ∼0.45 Sv of Pacific water northwestward along the Chukchi continental slope. Only 62% of this water emanates from Barrow Canyon, while the rest (38%) is fed by a westward jet extending from the southern Beaufort Sea. The jet merges with the outflow from the canyon, forming the CSC. Due to these two distinct origins, the slope current in the model has a double velocity core at times. This is consistent with the double-core structure of the slope current seen in ship-based observations. Seasonal changes in the volume, heat, and freshwater transports by the slope current appear to be related to the changes in the upstream flows. A tracer diagnostic in the model suggests that the part of the slope current over the upper continental slope continues westward toward the East Siberian Sea, while the portion of the current overlying deeper isobaths flows northward into the Chukchi Borderland, where it ultimately gets entrained into the Beaufort Gyre. Our study provides a detailed and complete picture of the slope current. This work was funded by the National Key Research and Development Program of China (Grant 2017YFA0604600), the Fundamental Research Funds for the Central Universities (Grant 2019B81214), the National Natural Science Foundation of China (Grant 41676019), the Postgraduate Research & Practice Innovation Program of Jiangsu Province (Grant KYCX19_0384), the National Science Foundation (Grants OPP-1822334, ...