Circulation patterns in the lower Arctic Ocean derived from geochemical data

• Published in: Journal of Oceanography
• Main Authors: Ikeda, Motoyoshi, Tanaka, Shinichi S., Watanabe, Yutaka
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer
• Subjects: Arctic Ocean; Ocean circulation; Arctic-Atlantic water exchange; Geochemical data; Geochemical conservative tracer; Arctic; Barents Sea; Canada; Greenland; Laptev Sea; Pacific; canada basin; Chukchi; Fram Strait; Greenland Sea; laptev; Nordic Seas
• Online Access: http://hdl.handle.net/2115/71647; https://doi.org/10.1007/s10872-018-0472-2

Climatological water-mass structures were identified in the Arctic Ocean using the geochemical dataset in the Hydrochemical Atlas of the Arctic Ocean (HAAC) as well as data on a geochemically conserved parameter, PO4*, based on phosphate and dissolved oxygen. In the upper ocean above a depth of 500m, the HAAC was found to reliably depict the boundary between Pacific-Origin Water (P-Water) and Atlantic-Origin Water (A-Water), which is aligned 135 degrees E-45 degrees W near the surface but rotates counterclockwise with depth. Thus, the Arctic and Atlantic oceans exchange high-silicate P-Water and low-silicate A-Water. The PO4* field in the lower ocean below a depth of 1500m was analyzed statistically, and the results indicated that the Eurasian Basin receives low-PO4* Nordic Seas Deep Water, which flows along the bottom from the Greenland Sea. The routes from the upper ocean to the lower ocean were determined. Only the southern portion of the Canada Basin, which receives water from the Chukchi and Beaufort Seas, has high PO4* levels; the rest of the Amerasian Basin receives low-PO4* water from the Laptev Sea and/or the Barents Sea. The Eurasian Basin receives moderate levels of PO4* from the Fram Strait and from the intermediate layer. The intermediate-layer water gradually travels up from the lower ocean and returns to the Atlantic, entraining the subsurface portion. It is likely that high-PO4* water occasionally flows down from the upper ocean along Greenland, making the Eurasian Basin heterogeneous.