One mechanism contributing to co-variabilityof the Atlantic inflow branches to the Arctic

摘要

The two-branched inflow of warm and saline Atlantic Water to the Arctic is the majorcontributor of oceanic heat to the Arctic climate system. However, while the Atlantic Waterentering the Arctic through the Fram Strait retains a large part of its heat as it flows along theArctic continental slope, the branch flowing through the shallow Barents Sea releases asubstantial amount of heat to the atmosphere. Hence, the pathway of the Atlantic Water intothe Arctic to a large degree determines the short term fate of its heat. Here we show eventsin which the relative strengths of the two branches are affected by wind-induced Ekmantransportoff the northern Barents Sea shelf. The resulting decrease in sea surface heightinduces a cyclonic circulation anomaly along the slope encircling the northern Barents Seashelf area, which enhances the flow through the Barents Sea while weakening the branchflowing along the Arctic continental slope.