气候变化领域集成服务门户(CCPortal): Evaluation of subseasonal impacts of the MJO/BSISO in the East Asian extended summer

CCPortal

DOI	10.1007/s00382-021-05656-5
	Evaluation of subseasonal impacts of the MJO/BSISO in the East Asian extended summer
	Chang C.-H.; Johnson N.C.; Yoo C.
发表日期	2021
ISSN	0930-7575
起始页码	1541
结束页码	1569
卷号	56 期号:2021-11-12
英文摘要	The Madden–Julian Oscillation (MJO)/Boreal Summer Intraseasonal Oscillation (BSISO) has been considered an important climate mode of variability on subseasonal timescales for East Asian summer. However, it is unclear how well the MJO/BSISO indices would serve as guidance for subseasonal forecasts. Using a probabilistic forecast model determined through multiple linear regression (MLR) with MJO, ENSO, and long-term trend as predictors, we examine lagged impacts of each predictor on East Asia extended summer (May–October) climate from 1982 to 2015. The forecast skills of surface air temperature (T2m) contributed by each predictor is evaluated for lead times out to five weeks. We also provide a systematic evaluation of three commonly used, real-time MJO/BSISO indices in the context of lagged temperature impacts over East Asia. It is found that the influence of the trend provides substantial summertime skill over broad regions of East Asia on subseasonal timescales. In contrast, the MJO influence shows regional as well as phase dependence outside the tropical band of the main action centers of the MJO convective anomalies. All three MJO/BSISO indices generate forecasts that yield high skill scores for week 1 forecasts. For some initial phases of the MJO/BSISO, skill reemerges over some regions for lead times of 3–5 weeks. This emergence indicates the existence of windows of opportunity for skillful subseasonal forecasts over East Asia in summer. We also explore the dynamics that contribute to the elevated skills at long lead times over Tibet and Taiwan–Philippine regions following the initial state of phases 7 and 5, respectively. The elevated skill is rooted in a wave train forced by the MJO convective heating over the Arabian Sea and feedbacks between MJO convection and SSTs in Taiwan–Philippine region. Two out of the three commonly used MJO/BSISO indices tend to identify MJO events that evolve consistently in time, allowing them to serve as reliable predictors for subseasonal forecasts for up to 5 weeks. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.
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/183248
作者单位	Center for Climate/Environment Change Prediction Research, Ewha Womans University, Seoul, South Korea; Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan; Princeton University/Geophysical Fluid Dynamics Laboratory, Princeton, NJ, United States; Department of Climate and Energy Systems Engineering, Ewha Womans University, Seoul, South Korea
推荐引用方式 GB/T 7714	Chang C.-H.,Johnson N.C.,Yoo C.. Evaluation of subseasonal impacts of the MJO/BSISO in the East Asian extended summer[J],2021,56(2021-11-12).
APA	Chang C.-H.,Johnson N.C.,&Yoo C..(2021).Evaluation of subseasonal impacts of the MJO/BSISO in the East Asian extended summer.Climate Dynamics,56(2021-11-12).
MLA	Chang C.-H.,et al."Evaluation of subseasonal impacts of the MJO/BSISO in the East Asian extended summer".Climate Dynamics 56.2021-11-12(2021).