Lack of bipolar see-saw in response to Southern Ocean wind reduction

A cessation of the Atlantic meridional overturning circulation (AMOC) significantly reduces northward oceanic heat transport. In response to anomalous freshwater flux, this leads to the classic 'bipolar see-saw' pattern of northern cooling and southern warming in surface air and ocean temp...

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Detalles Bibliográficos
Autores: Levermann, A., Schewe, J., Montoya Redondo, María Luisa
Tipo de recurso: artículo
Fecha de publicación:2007
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/51893
Acceso en línea:https://hdl.handle.net/20.500.14352/51893
Access Level:acceso abierto
Palabra clave:52
Meridional overturning circulation
Thermohaline circulation
Climate-change
Intermediate complexity
2nd-order moments
Hemisphere winds
System model
Performance
Greenland
Sensitivity
Astrofísica
Astronomía (Física)
Descripción
Sumario:A cessation of the Atlantic meridional overturning circulation (AMOC) significantly reduces northward oceanic heat transport. In response to anomalous freshwater flux, this leads to the classic 'bipolar see-saw' pattern of northern cooling and southern warming in surface air and ocean temperatures. By contrast, as shown here in a coupled climate model, both northern and southern cooling are observed for an AMOC reduction in response to reduced wind stress in the Southern Ocean (SO). For very weak SO wind stress, not only the overturning circulation collapses, but sea ice export from the SO is strongly reduced. Consequently, sea ice extent and albedo increase in this region. The resulting cooling overcompensates the warming by the reduced northward heat transport. The effect depends continuously on changes in wind stress and is reversed for increased winds. It may have consequences for abrupt climate change, the last deglaciation and climate sensitivity to increasing atmospheric CO_2 concentration.