气候变化领域集成服务门户(CCPortal): Impact of the quasi-biennial oscillation on the northern winter stratospheric polar vortex in CMIP5/6 models

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DOI	10.1175/JCLI-D-19-0663.1
	Impact of the quasi-biennial oscillation on the northern winter stratospheric polar vortex in CMIP5/6 models
	Rao J.; Garfinkel C.I.; White I.P.
发表日期	2020
ISSN	0894-8755
起始页码	4787
结束页码	4813
卷号	33 期号:11
英文摘要	Using 16 CMIP5/6 models with a spontaneously generated quasi-biennial oscillation (QBO)-like phenomenon, this study investigates the impact of the QBO on the northern winter stratosphere. Eight of the models simulate aQBOwith a period similar to that observed (25-31 months), with other models simulating a QBO period of 20-40 months. Regardless of biases in QBO periodicity, the Holton-Tan relationship can be well simulated in CMIP5/6 models with more planetary wave convergence in the polar stratosphere in easterly QBOwinters. This wave polar convergence occurs not only due to the Holton-Tan mechanism, but also in the midlatitude upper stratosphere where an Elissen-Palm (E-P) flux divergence dipole (with poleward E-P flux) is simulated in most models. The wave response in the upper stratosphere appears related to changes in the background circulation through a directly excited meridional-vertical circulation cell above the maximum tropical QBO easterly center. The midlatitude upwelling in this anticlockwise cell is split into two branches, and the north branch descends in the Arctic region and warms the stratospheric polar vortex. Most models underestimate the Arctic stratospheric warming in early winter during easterly QBO. Further analysis suggests that this bias is not due to an overly weak response to a given QBO phase, as the models simulate a realistic response if one focuses on similar QBO phases. Rather, the model bias is due to the too-low frequency of strong QBO winds in the lower stratosphere in early winter simulated by the models. © 2020 American Meteorological Society.
英文关键词	Oscillators (mechanical); Vortex flow; Flux divergences; Lower stratosphere; Planetary Waves; Polar stratosphere; Quasi-biennial oscillation; Stratospheric polar vortex; Stratospheric warmings; Vertical circulation; Climate models; atmospheric dynamics; climate modeling; computer simulation; planetary wave; polar vortex; quasi-biennial oscillation; stratosphere; winter; zonal wind
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/171276
作者单位	Fredy and Nadine Herrmann Institute of Earth Sciences, Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, Israel; Key Laboratory of Meteorological Disaster, Min. of Educ./Jt. Intl. Res. Lab. of Climate and Environ. Change/Collab. Innov. Ctr. on Forecast and Eval. of Meteorol. Disasters, Nanjing University of Information Science and Technology, Nanjing, China
推荐引用方式 GB/T 7714	Rao J.,Garfinkel C.I.,White I.P.. Impact of the quasi-biennial oscillation on the northern winter stratospheric polar vortex in CMIP5/6 models[J],2020,33(11).
APA	Rao J.,Garfinkel C.I.,&White I.P..(2020).Impact of the quasi-biennial oscillation on the northern winter stratospheric polar vortex in CMIP5/6 models.Journal of Climate,33(11).
MLA	Rao J.,et al."Impact of the quasi-biennial oscillation on the northern winter stratospheric polar vortex in CMIP5/6 models".Journal of Climate 33.11(2020).