气候变化领域集成服务门户(CCPortal): A regime perspective on the north atlantic eddy-driven jet response to sudden stratospheric warmings

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DOI	10.1175/JCLI-D-19-0702.1
	A regime perspective on the north atlantic eddy-driven jet response to sudden stratospheric warmings
	Maycock A.C.; Masukwedza G.I.T.; Hitchcock P.; Simpson I.R.
发表日期	2020
ISSN	0894-8755
起始页码	3901
结束页码	3917
卷号	33 期号:9
英文摘要	Changes to the preferred states, or regime behavior, of the North Atlantic eddy-driven jet (EDJ) following a major sudden stratospheric warming (SSW) is examined using a large ensemble experiment from the Canadian Middle Atmosphere Model in which the stratosphere is nudged toward an SSW. In the 3 months following the SSW (January-March), the North Atlantic EDJ shifts equatorward by;38, on average; this arises from an increased occurrence of the EDJ's south regime and reductions in its north and central regimes. Qualitatively similar behavior is shown in a reanalysis dataset. We show that under SSW conditions the south regime becomes more persistent and that this can explain the overall increase in the EDJ latitude decorrelation time scale. A cluster analysis reveals that, following the SSW, the south EDJ regime is characterized by weaker low-level baroclinicity and eddy heat fluxes in the North Atlantic Ocean. We hypothesize, therefore, that the increased persistence of the south regime is related to the weaker baroclinicity leading to slower growth rates of the unstable modes and hence a slower buildup of eddy heat flux, which has been shown to precede EDJ transitions. In the North Atlantic sector, the surface response to the SSW projects onto a negative North Atlantic Oscillation (NAO) pattern, with almost no change in the east Atlantic (EA) pattern. This behavior appears to be distinct from the modeled intrinsic variability in the EDJ, where the jet latitude index captures variations in both the NAO and EA patterns. The results offer new insight into the mechanisms for stratosphere-troposphere coupling following SSWs. © 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; Cluster analysis; Heat flux; Meteorology; Intrinsic variabilities; Middle atmosphere model; North Atlantic Ocean; North Atlantic oscillations; Stratosphere-troposphere coupling; Stratospheric warmings; Sudden stratospheric warming; Surface response; Oceanography; atmospheric modeling; baroclinic mode; correlation; data set; eddy; heat flux; jet stream; qualitative analysis; stratosphere; sudden stratospheric warming; 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/171341
作者单位	School of Earth and Environment, University of Leeds, Leeds, United Kingdom; Zimbabwe Meteorological Services Department, Harare, Zimbabwe; Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY, United States; Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, United States; Department of Geography, University of Sussex, Brighton, United Kingdom
推荐引用方式 GB/T 7714	Maycock A.C.,Masukwedza G.I.T.,Hitchcock P.,et al. A regime perspective on the north atlantic eddy-driven jet response to sudden stratospheric warmings[J],2020,33(9).
APA	Maycock A.C.,Masukwedza G.I.T.,Hitchcock P.,&Simpson I.R..(2020).A regime perspective on the north atlantic eddy-driven jet response to sudden stratospheric warmings.Journal of Climate,33(9).
MLA	Maycock A.C.,et al."A regime perspective on the north atlantic eddy-driven jet response to sudden stratospheric warmings".Journal of Climate 33.9(2020).