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DOI	10.1175/JCLI-D-19-0192.1
	Dynamics of the ENSO teleconnection and NAO variability in the North Atlantic-European late winter
	Mezzina B.; García-Serrano J.; Bladé I.; Kucharski F.
发表日期	2020
ISSN	0894-8755
起始页码	907
结束页码	923
卷号	33 期号:3
英文摘要	The winter extratropical teleconnection of El Niño-Southern Oscillation (ENSO) in the North Atlantic-European (NAE) sector remains controversial, concerning both the amplitude of its impacts and the underlying dynamics. However, a well-established response is a late-winter (January-March) signal in sea level pressure (SLP) consisting of a dipolar pattern that resembles the North Atlantic Oscillation (NAO). Clarifying the relationship between this ''NAO-like'' ENSO signal and the actual NAO is the focus of this study. The ENSO-NAE teleconnection and NAO signature are diagnosed by means of linear regression onto the sea surface temperature (SST) Niño-3.4 index and an EOF-based NAO index, respectively, using long-term reanalysis data (NOAA-20CR, ERA-20CR). While the similarity in SLP is evident, the analysis of anomalous upper-tropospheric geopotential height, zonal wind, and transient-eddy momentum flux, as well as precipitation and meridional eddy heat flux, suggests that there is no dynamical link between the phenomena. The observational results are further confirmed by analyzing two 10-member ensembles of atmosphere-only simulations (using an intermediate-complexity and a state-of-the-art model) with prescribed SSTs over the twentieth century. The SST-forced variability in the Northern Hemisphere is dominated by the extratropical ENSO teleconnection, which provides modest but significant SLP skill in the NAE midlatitudes. The regional internally generated variability, estimated from residuals around the ensemble mean, corresponds to the NAO pattern. It is concluded that distinct dynamics are at play in the ENSO-NAE teleconnection and NAO variability, and caution is advised when interpreting the former in terms of the latter. © 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; Dynamics; Heat flux; Sea level; Surface waters; Geo-potential heights; Intermediate complexity; North Atlantic oscillations; Northern Hemispheres; Sea level pressure; Sea surface temperature (SST); Southern oscillation; Underlying dynamics; Climatology; atmospheric dynamics; computer simulation; El Nino-Southern Oscillation; North Atlantic Oscillation; numerical model; sea surface temperature; seasonal variation; teleconnection; Atlantic Ocean; Atlantic Ocean (North); Europe
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/171477
作者单位	Barcelona Supercomputing Center, Barcelona, Spain; Barcelona Supercomputing Center, Group of Meteorology, Universitat de Barcelona, Barcelona, Spain; Group of Meteorology, Universitat de Barcelona, Barcelona, Spain; Abdus Salam International Centre for Theoretical Physics, Trieste, Italy
推荐引用方式 GB/T 7714	Mezzina B.,García-Serrano J.,Bladé I.,et al. Dynamics of the ENSO teleconnection and NAO variability in the North Atlantic-European late winter[J],2020,33(3).
APA	Mezzina B.,García-Serrano J.,Bladé I.,&Kucharski F..(2020).Dynamics of the ENSO teleconnection and NAO variability in the North Atlantic-European late winter.Journal of Climate,33(3).
MLA	Mezzina B.,et al."Dynamics of the ENSO teleconnection and NAO variability in the North Atlantic-European late winter".Journal of Climate 33.3(2020).