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DOI	10.1175/JCLI-D-19-0865.1
	MJO teleconnections over the PNA region in climate models. Part II: Impacts of the MJO and basic state
	Wang J.; Kim H.; Kim D.; Henderson S.A.; Stan C.; Maloney E.D.
发表日期	2020
ISSN	0894-8755
起始页码	5081
结束页码	5101
卷号	33 期号:12
英文摘要	In an assessment of 29 global climate models (GCMs), Part I of this study identified biases in boreal winter MJO teleconnections in anomalous 500-hPa geopotential height over the Pacific-North America (PNA) region that are common to many models: an eastward shift, a longer persistence, and a larger amplitude. In Part II, we explore the relationships of the teleconnection metrics developed in Part I with several existing and newly developed MJO and basic state (the mean subtropical westerly jet) metrics. The MJO and basic state diagnostics indicate that the MJO is generally weaker and less coherent and propagates faster in models compared to observations. The mean subtropical jet also exhibits notable biases such as too strong amplitude, excessive eastward extension, or southward shift. The following relationships are found to be robust among the models: 1) models with a faster MJO propagation tend to produce weaker teleconnections; 2) models with a less coherent eastward MJO propagation tend to simulate more persistent MJO teleconnections; 3) models with a stronger westerly jet produce stronger and eastward shifted MJO teleconnections; 4) models with an eastward extended jet produce an eastward shift in MJO teleconnections; and 5) models with a southward shifted jet produce stronger MJO teleconnections. The results are supported by linear baroclinic model experiments. Our results suggest that the larger amplitude and eastward shift biases in GCM MJO teleconnections can be attributed to the biases in the westerly jet, and that the longer persistence bias is likely due to the lack of coherent eastward MJO propagation. © 2020 American Meteorological Society.
英文关键词	Climatology; Tropics; Baroclinic models; Boreal winters; Geo-potential heights; Global climate model; Pacific-north america; Subtropical jet; Teleconnections; Climate models; baroclinic motion; climate modeling; jet; Madden-Julian oscillation; teleconnection; wave propagation; westerly; North America; Pacific Ocean
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/171506
作者单位	School of Marine and Atmospheric Sciences, Stony Brook University, State University of New York, Stony Brook, NY, United States; Department of Atmospheric Sciences, University of Washington, Seattle, WA, United States; Department of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison, Madison, WI, United States; Department of Atmospheric, Oceanic, and Earth Sciences, George Mason University, Fairfax, VA, United States; Department of Atmospheric Science, Colorado State University, Fort Collins, CO, United States
推荐引用方式 GB/T 7714	Wang J.,Kim H.,Kim D.,et al. MJO teleconnections over the PNA region in climate models. Part II: Impacts of the MJO and basic state[J],2020,33(12).
APA	Wang J.,Kim H.,Kim D.,Henderson S.A.,Stan C.,&Maloney E.D..(2020).MJO teleconnections over the PNA region in climate models. Part II: Impacts of the MJO and basic state.Journal of Climate,33(12).
MLA	Wang J.,et al."MJO teleconnections over the PNA region in climate models. Part II: Impacts of the MJO and basic state".Journal of Climate 33.12(2020).