|Title||A note on the stability indicator of the Atlantic meridional overturning circulation|
|Publication Type||Journal Article|
|Year of Publication||2014|
|Authors||Liu W, Liu Z.Y|
|Journal||Journal of Climate|
|Type of Article||Article|
|Keywords||ccsm3; model; multiple equilibria regime; Ocean circulation; stability; Thermocline circulation; thermohaline circulation|
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.