气候变化领域集成服务门户(CCPortal): ENSO feedbacks and their relationships with the mean state in a flux adjusted ensemble

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DOI	10.1007/s00382-016-3270-9
	ENSO feedbacks and their relationships with the mean state in a flux adjusted ensemble
	Ferrett S.; Collins M.
发表日期	2019
ISSN	0930-7575
起始页码	7189
结束页码	7208
卷号	52 期号:12
英文摘要	The El Niño Southern Oscillation (ENSO) is governed by a combination of amplifying and damping ocean–atmosphere feedbacks in the equatorial Pacific. Here we quantify these feedbacks in a flux adjusted HadCM3 perturbed physics ensemble under present day conditions and a future emissions scenario using the Bjerknes Stability Index (BJ index). Relationships between feedbacks and both the present day biases and responses under climate change of the mean equatorial Pacific climate are investigated. Despite minimised mean sea surface temperature biases through flux adjustment, the important dominant ENSO feedbacks still show biases with respect to observed feedbacks and inter-ensemble diversity. The dominant positive thermocline and zonal advective feedbacks are found to be weaker in ensemble members with stronger mean zonal advection. This is due to a weaker sensitivity of the thermocline slope and zonal surface ocean currents in the east Pacific to surface wind stress anomalies. A drier west Pacific is also found to be linked to weakened shortwave and latent heat flux damping, suggesting a link between ENSO characteristics and the hydrological cycle. In contrast to previous studies using the BJ index that find positive relationships between the index and ENSO amplitude, here they are weakly or negatively correlated, both for present day conditions and for projected differences. This is caused by strong thermodynamic damping which dominates over positive feedbacks, which alone approximate ENSO amplitude well. While the BJ index proves useful for individual linear feedback analysis, we urge caution in using the total linear BJ index alone to assess the reasons for ENSO amplitude biases and its future change in models. © 2016, The Author(s).
英文关键词	ENSO; Feedbacks; Pacific; Stability
语种	英语
scopus关键词	climate change; climate feedback; El Nino-Southern Oscillation; latent heat flux; sea surface temperature; wind stress; Pacific Ocean; Pacific Ocean (Equatorial); Pacific Ocean (West)
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/146293
作者单位	College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom
推荐引用方式 GB/T 7714	Ferrett S.,Collins M.. ENSO feedbacks and their relationships with the mean state in a flux adjusted ensemble[J],2019,52(12).
APA	Ferrett S.,&Collins M..(2019).ENSO feedbacks and their relationships with the mean state in a flux adjusted ensemble.Climate Dynamics,52(12).
MLA	Ferrett S.,et al."ENSO feedbacks and their relationships with the mean state in a flux adjusted ensemble".Climate Dynamics 52.12(2019).