气候变化领域集成服务门户(CCPortal): Contribution of tropical instability waves to ENSO irregularity

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DOI	10.1007/s00382-018-4217-0
	Contribution of tropical instability waves to ENSO irregularity
	Holmes R.M.; McGregor S.; Santoso A.; England M.H.
发表日期	2019
ISSN	0930-7575
起始页码	1837
结束页码	1855
卷号	52 期号:2020-03-04
英文摘要	Tropical instability waves (TIWs) are a major source of internally-generated oceanic variability in the equatorial Pacific Ocean. These non-linear phenomena play an important role in the sea surface temperature (SST) budget in a region critical for low-frequency modes of variability such as the El Niño–Southern Oscillation (ENSO). However, the direct contribution of TIW-driven stochastic variability to ENSO has received little attention. Here, we investigate the influence of TIWs on ENSO using a 1 / 4 ∘ ocean model coupled to a simple atmosphere. The use of a simple atmosphere removes complex intrinsic atmospheric variability while allowing the dominant mode of air−sea coupling to be represented as a statistical relationship between SST and wind stress anomalies. Using this hybrid coupled model, we perform a suite of coupled ensemble forecast experiments initiated with wind bursts in the western Pacific, where individual ensemble members differ only due to internal oceanic variability. We find that TIWs can induce a spread in the forecast amplitude of the Niño 3 SST anomaly 6-months after a given sequence of WWBs of approximately ±45% the size of the ensemble mean anomaly. Further, when various estimates of stochastic atmospheric forcing are added, oceanic internal variability is found to contribute between about 20 % and 70 % of the ensemble forecast spread, with the remainder attributable to the atmospheric variability. While the oceanic contribution to ENSO stochastic forcing requires further quantification beyond the idealized approach used here, our results nevertheless suggest that TIWs may impact ENSO irregularity and predictability. This has implications for ENSO representation in low-resolution coupled models. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	El Niño–Southern Oscillation; Hybrid coupled model; Ocean general circulation model; Predictability; Stochastic forcing; Tropical instability waves
语种	英语
scopus关键词	El Nino-Southern Oscillation; instability; numerical model; oceanic general circulation model; prediction; stochasticity; tropical cyclone; Pacific Ocean; Pacific Ocean (Equatorial)
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/146511
作者单位	Climate Change Research Centre and ARC Centre of Excellence for Climate System Science, Universityof New South Wales, Sydney, Australia; School of Mathematics and Statistics, University of New South Wales, Sydney, Australia; School of Earth, Atmosphere and Environment, Monash University, Melbourne, Australia; Centre for Southern Hemisphere Oceans Research (CSHOR), CSIRO Oceans and Atmosphere, Hobart, Australia
推荐引用方式 GB/T 7714	Holmes R.M.,McGregor S.,Santoso A.,et al. Contribution of tropical instability waves to ENSO irregularity[J],2019,52(2020-03-04).
APA	Holmes R.M.,McGregor S.,Santoso A.,&England M.H..(2019).Contribution of tropical instability waves to ENSO irregularity.Climate Dynamics,52(2020-03-04).
MLA	Holmes R.M.,et al."Contribution of tropical instability waves to ENSO irregularity".Climate Dynamics 52.2020-03-04(2019).