气候变化领域集成服务门户(CCPortal): Locally and remotely forced subtropical AMOC variability: A matter of time scales

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DOI	10.1175/JCLI-D-19-0844.1
	Locally and remotely forced subtropical AMOC variability: A matter of time scales
	Jamet Q.; Dewar W.K.; Wienders N.; Deremble B.; Close S.; Penduff T.
发表日期	2020
ISSN	0894-8755
起始页码	5155
结束页码	5172
卷号	33 期号:12
英文摘要	Mechanisms driving the North Atlantic meridional overturning circulation (AMOC) variability at low frequency are of central interest for accurate climate predictions. Although the subpolar gyre region has been identified as a preferred place for generating climate time-scale signals, their southward propagation remains under consideration, complicating the interpretation of the observed time series provided by the Rapid Climate Change-Meridional Overturning Circulation and Heatflux Array-Western Boundary Time Series (RAPID-MOCHA-WBTS) program. In this study, we aim at disentangling the respective contribution of the local atmospheric forcing from signals of remote origin for the subtropical low-frequency AMOC variability. We analyze for this a set of four ensembles of a regional (20°S-55°N), eddy-resolving (1/12°) North Atlantic oceanic configuration, where surface forcing and open boundary conditions are alternatively permuted from fully varying (realistic) to yearly repeating signals. Their analysis reveals the predominance of local, atmospherically forced signal at interannual time scales (2-10 years), whereas signals imposed by the boundaries are responsible for the decadal (10-30 years) part of the spectrum. Due to this marked time-scale separation, we show that, although the intergyre region exhibits peculiarities, most of the subtropical AMOC variability can be understood as a linear superposition of these two signals. Finally, we find that the decadal-scale, boundary-forced AMOC variability has both northern and southern origins, although the former dominates over the latter, including at the site of the RAPID array (26.5°N). © 2020 American Meteorological Society.
英文关键词	Climate change; Time measurement; Time series; Tropics; Atmospheric forcing; Climate prediction; Interannual time scale; Linear superpositions; Meridional overturning circulations; Open boundary condition; Rapid climate change; Time scale separation; Oceanography; annual variation; atmospheric forcing; climate modeling; climate prediction; ensemble forecasting; frequency analysis; meridional circulation; Atlantic Ocean; Atlantic Ocean (North)
语种	英语
来源期刊	Journal of Climate
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/171507
作者单位	Univ. Grenoble Alpes, CNRS, IRD, Grenoble INP, IGE, Grenoble, France; Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL, United States; Laboratoire de Météorologie Dynamique, Paris, France; Laboratoire d'Océanographie Physique et Spatiale, Univ. de Bretagne Occidentale, Brest, France
推荐引用方式 GB/T 7714	Jamet Q.,Dewar W.K.,Wienders N.,et al. Locally and remotely forced subtropical AMOC variability: A matter of time scales[J],2020,33(12).
APA	Jamet Q.,Dewar W.K.,Wienders N.,Deremble B.,Close S.,&Penduff T..(2020).Locally and remotely forced subtropical AMOC variability: A matter of time scales.Journal of Climate,33(12).
MLA	Jamet Q.,et al."Locally and remotely forced subtropical AMOC variability: A matter of time scales".Journal of Climate 33.12(2020).