Numerical study of winter water formation in the Chukchi Sea: Roles and impacts of coastal polynyas

• Published in: Journal of Geophysical Research: Oceans
• Main Authors: Kawaguchi, Y, Tamura, T, Nishino, S, Kikuchi, T, Itoh, M, Mitsudera, H
• Format: Article in Journal/Newspaper
• Language: English
• Published: Amer Geophysical Union 2011
• Subjects: Earth Sciences; Oceanography; Physical Oceanography; Arctic; Barrow Canyon; Bering Strait; Canada; Chukchi Sea; Chukchi Shelf; Arctic Basin; canada basin; Chukchi
• Online Access: https://doi.org/10.1029/2010JC006606; http://ecite.utas.edu.au/76869

Winter water formation is examined in the Chukchi Sea for the winters of 1992C2006using a primitive equation ocean model forced by NCEP wind and surface salinity fluxderived from SSM/I thin ice thickness estimates. The model is also forced by an externalinflow of 0.8 Sv through the Bering Strait. The model successfully reproduces theoceanic circulation on the Chukchi shelf, thus providing numerous insights intobehaviors of salt\enriched water produced on the shelf. The experiments show that undernortheasterly winds, northward throughflow across Barrow Canyon is reduced. Thisresults in salinity buildup under freezing conditions and ultimately in greaterenhancement of salinity of the waters carried into the Arctic Basin. The flow and salinityenhancement of the flow through Herald Canyon is less extreme but more steady thanthrough Barrow Canyon. Together with moored salinity in the Bering Strait, the modelresults estimate the actual salinity to be 32.9 0.8 psu and 32.7 0.3 psu, respectively,for waters moving through the Barrow and Herald Canyons. Both estimates are less than33.1 psu that is typically observed for the cold halostad layer in the Canada Basin,suggesting the importance of diapycnal mixing with saltier Atlantic origin water.