气候变化领域集成服务门户(CCPortal): Planetary and synoptic-scale dynamic control of extreme cold wave patterns over the United States

CCPortal

DOI	10.1007/s00382-019-04683-7
	Planetary and synoptic-scale dynamic control of extreme cold wave patterns over the United States
	Xie Z.; Black R.X.; Deng Y.
发表日期	2019
ISSN	0930-7575
起始页码	1477
结束页码	1495
卷号	53 期号:2020-03-04
英文摘要	The roles of planetary and synoptic-scale waves in extreme cold wave (ECW) events over the southeastern (SE) and northwestern (NW) United States (US) are studied using a spherical harmonic decomposition in conjunction with piecewise tendency diagnosis (PTD). Planetary waves and synoptic waves jointly work together to initiate ECW events. Notably, the planetary waves not only provide a direct contribution to circulation field enacting ECW events but also alter the background circulation field in such a manner that promotes synoptic waves growth via increases in regional barotropic deformation. The SE-ECW events, concurrent with the Northern Hemisphere annular mode (NAM) negative phase, feature high latitude intensification and subsequent southeastward movement of cold surface air temperature (SAT) anomalies. The planetary-scale pattern provides a sizable contribution to the total wave pattern on both sea level pressure (SLP) and upper level. Moreover, the negative NAM planetary anomaly acts to displace the jet equatorward and thereby increases the barotropic deformation of the synoptic-scale anomaly over southeastern US. PTD confirms that the planetary-scale barotropic deformation plays a key role in deepening the negative height anomaly with a secondary contribution from baroclinic growth. In contrast, NW-ECW events feature a regional SAT cold anomaly that intensified in situ in association with a quasi-stationary positive SLP anomaly with a substantial planetary-scale wave component. The upper level circulation is characterized by a pronounced anomalous ridge over the Gulf of Alaska and a northeast-southwest tilted negative height anomaly to its east. The negative height anomaly axis is orthogonal to the planetary-scale dilatation, result in a stronger planetary barotropic deformation of the incipient negative height anomaly. © 2019, The Author(s).
英文关键词	Barotropic deformation; Extreme cold wave; Large-scale meteorological pattern; Piecewise tendency diagnosis; Planetary wave
语种	英语
scopus关键词	annual variation; barotropic wave; cold wave; deformation; extreme event; planetary wave; United States
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146105
作者单位	International Center for Climate and Environment Sciences, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China; School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States
推荐引用方式 GB/T 7714	Xie Z.,Black R.X.,Deng Y.. Planetary and synoptic-scale dynamic control of extreme cold wave patterns over the United States[J],2019,53(2020-03-04).
APA	Xie Z.,Black R.X.,&Deng Y..(2019).Planetary and synoptic-scale dynamic control of extreme cold wave patterns over the United States.Climate Dynamics,53(2020-03-04).
MLA	Xie Z.,et al."Planetary and synoptic-scale dynamic control of extreme cold wave patterns over the United States".Climate Dynamics 53.2020-03-04(2019).