气候变化领域集成服务门户(CCPortal): The Impact of the Stratosphere on the MJO in a Forecast Model

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DOI	10.1029/2019JD032106
	The Impact of the Stratosphere on the MJO in a Forecast Model
	Martin Z.; Vitart F.; Wang S.; Sobel A.
发表日期	2020
ISSN	2169897X
卷号	125 期号:4
英文摘要	This study examines the relationship between the Madden-Julian oscillation (MJO) and stratospheric quasi-biennial oscillation (QBO) in a state-of-the-art global numerical weather forecast model. A set of 61-day model integrations, with 15 ensemble members, is performed across 84 start dates during December–February of 1989–2016. For 28 of those dates—every 1 January—the stratosphere is initialized from observation, and the model simulates stronger MJO events during observed easterly QBO phases (QBOE) than westerly QBO phases (QBOW). However, in these “control experiments,” the QBO's impact on the MJO is already present in the initial conditions, and the direct influence of the model stratosphere during the simulation is unclear. To explore this more directly, the model was rerun with an artificially imposed QBOE and QBOW state, replacing the existing stratospheric initial condition above 150 hPa while leaving the troposphere unaltered. Though the imposed QBO states weaken faster in the model than in observations, their persistence is comparable to the control simulations. The MJO is stronger during imposed-QBOE experiments than imposed-QBOW, and differences are statistically significant by several metrics, though magnitude of the differences is smaller than in observations. Analysis suggests that the strength of the MJO response to the QBO increases for simulations with stronger upper-tropospheric temperature differences and for simulations in which the MJO at the initialization time is strong and active over the Maritime Continent. However, tropospheric conditions still appear to have a dominant effect in explaining the apparent QBO influence in this model. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Forecast modeling; Madden-Julian Oscillation; Quasi-biennial oscillation; Stratosphere-troposphere interaction
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/186147
作者单位	Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY, United States; European Centre for Medium-Range Weather Forecasting, Reading, United Kingdom; Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States
推荐引用方式 GB/T 7714	Martin Z.,Vitart F.,Wang S.,et al. The Impact of the Stratosphere on the MJO in a Forecast Model[J],2020,125(4).
APA	Martin Z.,Vitart F.,Wang S.,&Sobel A..(2020).The Impact of the Stratosphere on the MJO in a Forecast Model.Journal of Geophysical Research: Atmospheres,125(4).
MLA	Martin Z.,et al."The Impact of the Stratosphere on the MJO in a Forecast Model".Journal of Geophysical Research: Atmospheres 125.4(2020).