DOI: 10.1007/s00382-015-2921-6
Scopus记录号: 2-s2.0-84949556750
论文题名: The switching between zonal and blocked mid-latitude atmospheric circulation: a dynamical system perspective
作者: Faranda D. ; Masato G. ; Moloney N. ; Sato Y. ; Daviaud F. ; Dubrulle B. ; Yiou P.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2016
卷: 47, 期: 2017-05-06 起始页码: 1587
结束页码: 1599
语种: 英语
英文关键词: Blocking index
; Extremal index
; Mid-latitude circulation
英文摘要: Atmospheric mid-latitude circulation is dominated by a zonal, westerly flow. Such a flow is generally symmetric, but it can be occasionally broken up by blocking anticyclones. The subsequent asymmetric flow can persist for several days. In this paper, we apply new mathematical tools based on the computation of an extremal index in order to reexamine the dynamical mechanisms responsible for the transitions between zonal and blocked flows. We discard the claim that mid-latitude circulation features two distinct stable equilibria or chaotic regimes, in favor of a simpler mechanism that is well understood in dynamical systems theory: we identify the blocked flow as an unstable fixed point (or saddle point) of a single basin chaotic attractor, dominated by the westerlies regime. We also analyze the North Atlantic Oscillation and the Arctic Oscillation atmospheric indices, whose behavior is often associated with the transition between the two circulation regimes, and investigate analogies and differences with the bidimensional blocking indices. We find that the Arctic Oscillation index, which can be thought as a proxy for a hemispheric average of the Tibaldi–Molteni blocking index, tracks unstable fixed points. On the other hand, the North Atlantic Oscillation, representative only for local properties of the North Atlantic blocking dynamics, does not show any trace of the presence of unstable fixed points of the dynamics. © 2015, Springer-Verlag Berlin Heidelberg. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/53570
Appears in Collections: 过去全球变化的重建
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作者单位: LSCE, CEA Saclay l’Orme des Merisiers, CNRS UMR 8212 CEA-CNRS-UVSQ, University Paris-Saclay, Gif-sur-Yvette, France; Department of Meteorology/NCAS, University of Reading, Reading, United Kingdom; London Mathematical Laboratory, 14 Buckingham Street, London, United Kingdom; RIES/Department of Mathematics, Hokkaido University, Kita-ku, Sapporo, Hokkaido, Japan; Laboratoire SPHYNX, SPEC, CEA Saclay, CNRS UMR 3680, Gif-sur-Yvette, France
Recommended Citation:
Faranda D.,Masato G.,Moloney N.,et al. The switching between zonal and blocked mid-latitude atmospheric circulation: a dynamical system perspective[J]. Climate Dynamics,2016-01-01,47(2017-05-06)