气候变化领域集成服务门户(CCPortal): Longer Duration of the Weak Stratospheric Vortex During Extreme El Niño Events Linked to Spring Eurasian Coldness

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DOI	10.1029/2019JD032331
	Longer Duration of the Weak Stratospheric Vortex During Extreme El Niño Events Linked to Spring Eurasian Coldness
	Zhou X.; Chen Q.; Wang Z.; Xu M.; Zhao S.; Cheng Z.; Feng F.
发表日期	2020
ISSN	2169897X
卷号	125 期号:16
英文摘要	The stratosphere is a key link between El Niño and Eurasian surface climate in winter. Instead of the amplitude of the stratospheric response discussed by many previous studies, we focus on the persistence of wintertime extreme El Niño impacts through the stratospheric pathway to midlatitude Eurasia in spring. A novel approach is used by running WACCM4 with El Niño forcing imposed only during winter to isolate the stratospheric role in the following spring. We show that a descending signal with a strong deceleration of zonal wind throughout the atmosphere could reach the surface and persist in spring during extreme El Niño events, whereas during moderate El Niño events the signal is generally confined to the stratosphere. Two different mechanisms are involved in maintaining the tropospheric signal of extreme El Niño. Under the westerly regime, the planetary Rossby waves from the wave centers over East Asia and the North Pacific transmit the signals from the stratosphere to the troposphere; and under the easterly regime, strong tropospheric eddy feedback over the midlatitude Atlantic favors the persistence of tropospheric responses during extreme El Niño events. The prolonged stratospheric pathway of extreme El Niño events amplifies and extends the equatorward shift of the midlatitude jet, allowing southward intrusions of cold polar air into Eurasia. Such circulation changes induced by a prolonged stratospheric pathway can cause springtime coldness and daily cold extremes in midlatitude Eurasia. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	extreme El Niño; prolonged signal; springtime coldness; stratospheric pathway
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185828
作者单位	Plateau Atmosphere and Environment Key Laboratory of Sichuan Province, College of Atmospheric Science, Chengdu University of Information Technology, Chengdu, China; Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou, China; CIC-FEMD/ILCEC, Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information Science and Technology, Nanjing, China; Department of Atmospheric Sciences, University of Hawaiʻi at Mānoa, Honolulu, HI, United States
推荐引用方式 GB/T 7714	Zhou X.,Chen Q.,Wang Z.,et al. Longer Duration of the Weak Stratospheric Vortex During Extreme El Niño Events Linked to Spring Eurasian Coldness[J],2020,125(16).
APA	Zhou X..,Chen Q..,Wang Z..,Xu M..,Zhao S..,...&Feng F..(2020).Longer Duration of the Weak Stratospheric Vortex During Extreme El Niño Events Linked to Spring Eurasian Coldness.Journal of Geophysical Research: Atmospheres,125(16).
MLA	Zhou X.,et al."Longer Duration of the Weak Stratospheric Vortex During Extreme El Niño Events Linked to Spring Eurasian Coldness".Journal of Geophysical Research: Atmospheres 125.16(2020).