气候变化领域集成服务门户(CCPortal): Strengthened connection between springtime north atlantic oscillation and north atlantic tripole SST pattern since the late 1980s

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DOI	10.1175/JCLI-D-19-0628.1
	Strengthened connection between springtime north atlantic oscillation and north atlantic tripole SST pattern since the late 1980s
	Chen S.; Wu R.; Chen W.
发表日期	2020
ISSN	0894-8755
起始页码	2007
结束页码	2022
卷号	33 期号:5
英文摘要	This study reveals a marked enhancement in the relationship between the North Atlantic Oscillation (NAO) and North Atlantic tripole (NAT) sea surface temperature (SST) anomaly pattern during boreal spring since the late 1980s.Acomparative analysis is conducted for two periods before and after the late 1980s to understand the reasons for the above interdecadal change. During both periods, SST cooling in the northern tropical Atlantic during the positive phase of the NAT SST pattern results in an anomalous anticyclone over the subtropical western North Atlantic via a Rossby wave-type atmospheric response. The westerly wind anomalies along the north flank of the anomalous anticyclone are accompanied by a marked decrease in synoptic-scale eddies over the midlatitudes as well as cyclonic (anticyclonic) vorticity forcings at the north (south) side. As such, an NAO-like dipole atmospheric anomaly is induced over the North Atlantic, which in turn helps to maintain the NAT SST anomaly via modulating surface heat fluxes. The intensity of the synoptic-scale eddy feedback to mean flow is stronger after than before the late 1980s, which is related to interdecadal increase in the intensity of North Atlantic synoptic-scale eddies. This is followed by a stronger NAO-like atmospheric response to the NAT SST anomaly since the late 1980s. Further analysis shows that changes in the spatial structure of the spring NAO may also partly contribute to changes in the spring NAO- NAT SST connection around the late 1980s. In particular, spring NAO-related atmospheric anomalies are weaker and shift northward before the late 1980s, which reduces the contribution of theNAOto a tripole SST anomaly pattern in the North Atlantic. © 2020 American Meteorological Society.
英文关键词	Atmospheric pressure; Heat flux; Mechanical waves; Surface waters; Tropics; Atmospheric anomaly; Atmospheric response; Interdecadal changes; North Atlantic oscillations; Sea surface temperature anomalies; Spatial structure; Surface heat fluxes; Synoptic-scale eddies; Oceanography; cooling; North Atlantic Oscillation; Rossby wave; sea surface temperature; spring (season); temperature anomaly; westerly; 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/171429
作者单位	Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China; School of Earth Sciences, Zhejiang University, Hangzhou, China
推荐引用方式 GB/T 7714	Chen S.,Wu R.,Chen W.. Strengthened connection between springtime north atlantic oscillation and north atlantic tripole SST pattern since the late 1980s[J],2020,33(5).
APA	Chen S.,Wu R.,&Chen W..(2020).Strengthened connection between springtime north atlantic oscillation and north atlantic tripole SST pattern since the late 1980s.Journal of Climate,33(5).
MLA	Chen S.,et al."Strengthened connection between springtime north atlantic oscillation and north atlantic tripole SST pattern since the late 1980s".Journal of Climate 33.5(2020).