DOI: 10.1007/s00382-014-2274-6
Scopus记录号: 2-s2.0-84939872312
论文题名: Historical analogues of the recent extreme minima observed in the Atlantic meridional overturning circulation at 26°N
作者: Blaker A.T. ; Hirschi J.J.-M. ; McCarthy G. ; Sinha B. ; Taws S. ; Marsh R. ; Coward A. ; de Cuevas B.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2014
卷: 44, 期: 2017-01-02 起始页码: 457
结束页码: 473
语种: 英语
英文关键词: AMOC
; Events
; Minimum
; Model
; Observations
; RAPID
; Re-emergence
; SST anomalies
英文摘要: Observations of the Atlantic meridional overturning circulation (AMOC) by the RAPID 26°N array show a pronounced minimum in the northward transport over the winter of 2009/10, substantially lower than any observed since the initial deployment in April 2004. It was followed by a second minimum in the winter of 2010/2011. We demonstrate that ocean models forced with observed surface fluxes reproduce the observed minima. Examining output from five ocean model simulations we identify several historical events which exhibit similar characteristics to those observed in the winter of 2009/10, including instances of individual events, and two clear examples of pairs of events which happened in consecutive years, one in 1969/70 and another in 1978/79. In all cases the absolute minimum, associated with a short, sharp reduction in the Ekman component, occurs in winter. AMOC anomalies are coherent between the Equator and 50°N and in some cases propagation attributable to the poleward movement of the anomaly in the wind field is observed. We also observe a low frequency (decadal) mode of variability in the anomalies, associated with the North Atlantic Oscillation (NAO). Where pairs of events have occurred in consecutive years we find that atmospheric conditions during the first winter correspond to a strongly negative Arctic Oscillation (AO) index. Atmospheric conditions during the second winter are indicative of a more regional negative NAO phase, and we suggest that this persistence is linked to re-emergence of sea surface temperature anomalies in the North Atlantic for the events of 1969/70 and 2009/10. The events of 1978/79 do not exhibit re-emergence, indicating that the atmospheric memory for this pair of events originates elsewhere. Observation of AO patterns associated with cold winters over northwest Europe may be indicative for the occurrence of a second extreme winter over northwest Europe. © 2014, Springer-Verlag Berlin Heidelberg. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/54406
Appears in Collections: 过去全球变化的重建
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作者单位: National Oceanography Centre, Southampton, United Kingdom; University of Southampton, National Oceanography Centre, Southampton, United Kingdom
Recommended Citation:
Blaker A.T.,Hirschi J.J.-M.,McCarthy G.,et al. Historical analogues of the recent extreme minima observed in the Atlantic meridional overturning circulation at 26°N[J]. Climate Dynamics,2014-01-01,44(2017-01-02)