Volume, Freshwater, and Heat Fluxes through Davis Strait, 2004–05

Abstract

Davis Strait volume [?2.3 ± 0.7 Sv (1 Sv ≡ 106 m3 s?1); negative sign indicates southward transport], freshwater (?116 ± 41 mSv), and heat (20 ± 9 TW) fluxes estimated from objectively mapped 2004?05 moored array data do not differ significantly from values based on a 1987?90 array but are distributed differently across the strait. The 2004?05 array provided the first year-long measurements in the upper 100 m and over the shelves. The upper 100 m accounts for 39% (?0.9 Sv) of the net volume and 59% (?69 mSv) of the net freshwater fluxes. Shelf contributions are small: 0.4 Sv (volume), 15 mSv (freshwater), and 3 TW (heat) from the West Greenland shelf and ?0.1 Sv, ?7 mSv, and 1 TW from the Baffin Island shelf. Contemporaneous measurements of the Baffin Bay inflows and outflows indicate that volume and freshwater budgets balance to within 26% and 4%, respectively, of the net Davis Strait outflow. Davis Strait volume and freshwater fluxes nearly equal those from Fram Strait, indicating that both are significant Arctic freshwater pathways.