Open AccessCirculation, Heat, and Freshwater Transport at 36°N in the Atlantic
Author(s) -
Elaine L. McDonagh,
Paula McLeod,
Brian King,
Harry L. Bryden,
Sinhué TorresValdes
Publication year - 2010
Publication title -
journal of physical oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.706
H-Index - 143
eISSN - 1520-0485
pISSN - 0022-3670
DOI - 10.1175/2010jpo4176.1
Subject(s) - ocean gyre , oceanography , north atlantic deep water , hydrography , mesoscale meteorology , geology , thermohaline circulation , gulf stream , ridge , boundary current , climatology , ocean current , circumpolar deep water , geostrophic wind , flux (metallurgy) , subtropics , materials science , fishery , metallurgy , biology , paleontology
In May and June 2005, a transatlantic hydrographic section along 36°N was occupied. A velocity field is calculated using inverse methods. The derived 36°N circulation has an overturning transport (maximum in the overturning streamfunction) of 16.6 Sv (1 Sv ≡ 106 m3 s−1) at 1070 m. The heat transport across the section, 1.14 ± 0.12 PW, is partitioned into overturning and horizontal heat transports of 0.75 and 0.39 PW, respectively. The horizontal heat flux is set by variability at the gyre rather than by mesoscale. The freshwater flux across the section is 1.55 ± 0.18 Sv southward based on a 0.8-Sv flow from the Pacific through the Bering Strait at a salinity of 32.5 psu. The oceanic divergence of freshwater implies a net input of freshwater to the ocean of 0.75 Sv over the North Atlantic and Arctic between 36°N and the Bering Strait. Most (85%) of the recently ventilated upper North Atlantic Deep Water (water originating in the Labrador Sea) transport across the section occurs in the deep western boundary current rather than being associated with an interior pathway to the west of the mid-Atlantic ridge