气候变化领域集成服务门户(CCPortal): Latitudinal Structure of the Meridional Overturning Circulation Variability on Interannual to Decadal Time Scales in the North Atlantic Ocean

CCPortal

DOI	10.1175/JCLI-D-19-0215.1
	Latitudinal Structure of the Meridional Overturning Circulation Variability on Interannual to Decadal Time Scales in the North Atlantic Ocean
	Zou S.; Susan Lozier M.; Xu X.
发表日期	2020
ISSN	0894-8755
起始页码	3845
结束页码	3862
卷号	33 期号:9
英文摘要	The latitudinal structure of the Atlantic meridional overturning circulation (AMOC) variability in the North Atlantic is investigated using numerical results from three ocean circulation simulations over the past four to five decades. We show that AMOC variability south of the Labrador Sea (538N) to 258N can be decomposed into a latitudinally coherent component and a gyre-opposing component. The latitudinally coherent component contains both decadal and interannual variabilities. The coherent decadal AMOC variability originates in the subpolar region and is reflected by the zonal density gradient in that basin. It is further shown to be linked to persistent North Atlantic Oscillation (NAO) conditions in all three models. The interannual AMOC variability contained in the latitudinally coherent component is shown to be driven by westerlies in the transition region between the subpolar and the subtropical gyre (408-508N), through significant responses in Ekman transport. Finally, the gyre-opposing component principally varies on interannual time scales and responds to local wind variability related to the annual NAO. The contribution of these components to the total AMOC variability is latitude-dependent: 1) in the subpolar region, all models show that the latitudinally coherent component dominates AMOC variability on interannual to decadal time scales, with little contribution from the gyre-opposing component, and 2) in the subtropical region, the gyre-opposing component explains a majority of the interannual AMOC variability in two models, while in the other model, the contributions from the coherent and the gyre-opposing components are comparable. These results provide a quantitative decomposition of AMOC variability across latitudes and shed light on the linkage between different AMOC variability components and atmospheric forcing mechanisms. © 2020 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).
英文关键词	Atmospheric pressure; Time measurement; Tropics; Atlantic meridional overturning circulations; Atmospheric forcing; Interannual time scale; Interannual variability; Latitudinal structures; Meridional overturning circulations; North Atlantic Ocean; North Atlantic oscillations; Oceanography; annual variation; atmospheric forcing; decadal variation; meridional circulation; North Atlantic Oscillation; overturn; timescale; 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/171339
作者单位	Duke University, Durham, NC, United States; Center for Ocean-Atmospheric Prediction Studies, Florida State University, Tallahassee, FL, United States; Woods Hole Oceanographic Institution, Woods Hole, MA, United States
推荐引用方式 GB/T 7714	Zou S.,Susan Lozier M.,Xu X.. Latitudinal Structure of the Meridional Overturning Circulation Variability on Interannual to Decadal Time Scales in the North Atlantic Ocean[J],2020,33(9).
APA	Zou S.,Susan Lozier M.,&Xu X..(2020).Latitudinal Structure of the Meridional Overturning Circulation Variability on Interannual to Decadal Time Scales in the North Atlantic Ocean.Journal of Climate,33(9).
MLA	Zou S.,et al."Latitudinal Structure of the Meridional Overturning Circulation Variability on Interannual to Decadal Time Scales in the North Atlantic Ocean".Journal of Climate 33.9(2020).