A note on the stability indicator of the Atlantic meridional overturning circulation

TitleA note on the stability indicator of the Atlantic meridional overturning circulation
Publication TypeJournal Article
Year of Publication2014
AuthorsLiu W, Liu Z.Y
JournalJournal of Climate
Volume27
Pagination969-975
Date Published2014/01
Type of ArticleArticle
ISBN Number0894-8755
Accession NumberWOS:000329773100030
Keywordsccsm3; model; multiple equilibria regime; Ocean circulation; stability; Thermocline circulation; thermohaline circulation
Abstract

This study examines the validity of the net freshwater transport M-ov as a stability indicator of the Atlantic meridional overturning circulation (AMOC) in a low-resolution version of the NCAR Community Climate System Model, version 3 (CCSM3). It is shown that the sign of M-ov indicates the monostability or bistability of the AMOC, which is based on a hypothesis that a collapsed AMOC induces a zero net freshwater transport. In CCSM3, this hypothesis is satisfied in that the collapsed AMOC, with a nonzero strength, induces a zero net freshwater transport M-ov across the Atlantic basin by generating equivalent freshwater export M-ovS and freshwater import M-ovN at the southern and northern boundaries, respectively. Because of the satisfaction of the hypothesis, M-ov is consistent with a generalized indicator L for a slowly evolving AMOC, both of which correctly monitor the AMOC stability.

DOI10.1175/jcli-d-13-00181.1
Integrated Research Themes: 
Student Publication: 
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