Bryden, Harry L. and King, Brian A. and McCarthy, Gerard (2011) South Atlantic overturning circulation at 24°S. Journal of Marine Research, 69 (1). pp. 38-55. ISSN 0022-2402

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Abstract

To estimate the size of the meridional overturning circulation and the meridional heat and freshwater transports in the South Atlantic, we made a new transatlantic hydrographic section along 24°S in 2009 and we compare the resulting transports with those estimated for a historical section made in 1983. For the two sections, the overturning is estimated to be 21.5 Sv (2009) or 16.5 Sv (1983), the heat transport is northward at 0.7 PW (2009) or 0.4 PW (1983), and the freshwater transport is small but northward at 0.04 Sv (2009) or 0.17 Sv (1983). The differences in transports are primarily due to the different strengths of the southward Brazil Current transport during the occupation of the sections, 4.9 Sv (2009) or 12.3 Sv (1983). The freshwater transport associated with the meridional overturning circulation is estimated by two different methods for each of the two sections and is always southward ranging from –0.09 Sv to –0.34 Sv which means that the Atlantic meridional overturning circulation transports freshwater southward at 24°S. On the basis of theoretical studies, such southward freshwater transport at the southern boundary of the Atlantic Ocean means that the present Atlantic circulation has multiple equilibrium states, and that the one it occupies at present may be unstable to a sufficiently large freshwater event.

Item Type:	Article
Keywords:	Transport; Dedacal Variability; Pacific, Oceanography; Agulhas Leakage; Oceanic Fluxes; Exchange; Fresh-Water;
Academic Unit:	Faculty of Social Sciences > Geography Faculty of Social Sciences > Research Institutes > Irish Climate Analysis and Research Units, ICARUS
Item ID:	12199
Identification Number:	https://doi.org/10.1357/002224011798147633
Depositing User:	Gerard McCarthy
Date Deposited:	22 Jan 2020 15:50
Journal or Publication Title:	Journal of Marine Research
Publisher:	Sears Foundation for Marine Research
Refereed:	Yes
URI:	Publisher
Use Licence:	This item is available under a Creative Commons Attribution Non Commercial Share Alike Licence (CC BY-NC-SA). Details of this licence are available here

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