气候变化领域集成服务门户(CCPortal): Active and break phases of the South American summer monsoon: MJO influence and subseasonal prediction

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DOI	10.1007/s00382-021-05658-3
	Active and break phases of the South American summer monsoon: MJO influence and subseasonal prediction
	Grimm A.M.; Hakoyama L.R.; Scheibe L.A.
发表日期	2021
ISSN	0930-7575
起始页码	1203
结束页码	1226
卷号	56 期号:2021-11-12
英文摘要	The role of the Madden–Julian Oscillation (MJO) in producing active and break periods of the South American (SA) monsoon and the performance of the ECMWF and NCEP models in predicting these periods at multiweek lead times are assessed. Two monsoon indices, based on precipitation and wind, are proposed to characterize these periods. The models represent well the observed association of active and break monsoon days with large scale convection and circulation anomalies. Although reproducing approximately the distribution of active and break days proportions in each phase of the MJO cycle, models produce a phase shift between observed and simulated distributions because they establish the teleconnection between Central Pacific and South America, as well as its impacts, sooner than in observations. The predictive skill of both rainfall and wind anomalies is limited to about 2 weeks, with the monsoon wind index displaying higher correlation score till week 3. The forecast performance is apparently not affected by initialization on active or break monsoon days. However, it is higher for prediction of lower precipitation in break days than heavier rainfall in active days. Wind is much better predicted than rainfall for active days, which could be used for extreme rainfall events forecast. Although relatively small at shorter lead times, the MJO contribution is the major source of rainfall predictability after week 3. To improve the multiweek prediction of SA monsoon, models need not only to predict correctly the MJO phase, but also to reproduce in the right phase the MJO-related SA rainfall anomalies. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.
英文关键词	MJO; South America; Subseasonal prediction; Summer monsoon
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/183267
作者单位	Laboratory of Meteorology, Department of Physics, Federal University of Parana (UFPR), Caixa Postal 19044, Curitiba, PR 81531-980, Brazil
推荐引用方式 GB/T 7714	Grimm A.M.,Hakoyama L.R.,Scheibe L.A.. Active and break phases of the South American summer monsoon: MJO influence and subseasonal prediction[J],2021,56(2021-11-12).
APA	Grimm A.M.,Hakoyama L.R.,&Scheibe L.A..(2021).Active and break phases of the South American summer monsoon: MJO influence and subseasonal prediction.Climate Dynamics,56(2021-11-12).
MLA	Grimm A.M.,et al."Active and break phases of the South American summer monsoon: MJO influence and subseasonal prediction".Climate Dynamics 56.2021-11-12(2021).