DOI: 10.1007/s00382-012-1402-4
Scopus记录号: 2-s2.0-84874945877
论文题名: A 20-year coupled ocean-sea ice-atmosphere variability mode in the North Atlantic in an AOGCM
作者: Escudier R. ; Mignot J. ; Swingedouw D.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2013
卷: 40, 期: 2017-03-04 起始页码: 619
结束页码: 636
语种: 英语
英文关键词: Coupled climate model
; Decadal climate variability
; Ocean-sea ice-atmosphere coupling
; Subpolar North Atlantic
; Thermohaline circulation
英文摘要: In order to understand potential predictability of the ocean and climate at the decadal time scales, it is crucial to improve our understanding of internal variability at this time scale. Here, we describe a 20-year mode of variability found in the North Atlantic in a 1,000-year pre-industrial simulation of the IPSL-CM5A-LR climate model. This mode involves the propagation of near-surface temperature and salinity anomalies along the southern branch of the subpolar gyre, leading to anomalous sea-ice melting in the Nordic Seas, which then forces sea-level pressure anomalies through anomalous surface atmospheric temperatures. The wind stress associated to this atmospheric structure influences the strength of the East Greenland Current across the Denmark Strait, which, in turn, induces near-surface temperature and salinity anomalies of opposite sign at the entrance of the Labrador Sea. This starts the second half of the cycle after approximatively 10 years. The time scale of the cycle is thus essentially set by advection of tracers along the southern branch of the subpolar gyre, and by the time needed for anomalous East Greenland Current to accumulate heat and freshwater anomalies at the entrance of the Labrador Sea. The Atlantic meridional overturning circulation (AMOC) does not play a dominant role in the mode that is confined in the subpolar North Atlantic, but it also has a 20-year preferred timescale. This is due to the influence of the propagating salinity anomalies on the oceanic deep convection. The existence of this preferred timescale has important implications in terms of potential predictability of the North Atlantic climate in the model, although its realism remains questionable and is discussed. © 2012 Springer-Verlag. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/54931
Appears in Collections: 过去全球变化的重建
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作者单位: Institut Mediterrani d'Estudis Avancats, IMEDEA (CSIC-UIB), Mallorca, Spain; Laboratoire d'ocanographie et du climat: experimentation et approches numeriques, IPSL/UPMC/CNRS/IRD/MNHN, case 100, 4 place Jussieu, 75005 Paris, France; IPSL/LSCE, Gif-sur-Yvette, CEA Saclay, Orme des Merisiers, France
Recommended Citation:
Escudier R.,Mignot J.,Swingedouw D.. A 20-year coupled ocean-sea ice-atmosphere variability mode in the North Atlantic in an AOGCM[J]. Climate Dynamics,2013-01-01,40(2017-03-04)