超级厄尔尼诺现象模型。

A model for super El Niños.

机构信息

The University of Aizu, Aizuwakamatsu, Fukushima, 9658580, Japan.

Nanjing University of Information Science & Technology, Nanjing, 210044, China.

出版信息

Nat Commun. 2018 Jun 28;9(1):2528. doi: 10.1038/s41467-018-04803-7.

DOI:10.1038/s41467-018-04803-7

PMID:29955048

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6023905/

Abstract

Super El Niños, the strongest and most powerful of El Niños, impact economies, societies, and ecosystems disproportionately. Despite their importance, we do not fully understand how super El Niños develop their intensity and unique characteristics. Here, combining observational analyses with simple numerical simulations, we suggest that eastern Pacific intensified super El Niños result from the interaction of an El Niño and a positive Indian Ocean Dipole. Further, we identify a self-limiting behavior inherent to El Niño Southern Oscillation (ENSO) dynamics. This behavior-a consequence of the atmospheric Kelvin wave response that develops to the east of ENSO's convective anomalies-dampens sea surface temperature (SST) variations in the eastern Pacific, thereby preventing super El Niños from developing through tropical Pacific dynamics alone. Our model explains the features of the large 1972, 1982, and 1997 El Niños; the large SST anomalies during the 2015 El Niño, however, were likely enhanced by strong decadal variability.

摘要

超强厄尔尼诺现象是最强和最具影响力的厄尔尼诺现象之一，对经济、社会和生态系统造成了不成比例的影响。尽管它们很重要，但我们并不完全了解超强厄尔尼诺现象是如何发展出其强度和独特特征的。在这里，我们结合观测分析和简单的数值模拟，提出东太平洋增强型超强厄尔尼诺现象是厄尔尼诺现象和印度洋偶极子相互作用的结果。此外，我们还确定了厄尔尼诺南方涛动（ENSO）动力学中固有的自我限制行为。这种行为是对 ENSO 对流异常以东发展的大气开尔文波响应的结果，从而抑制了东太平洋海表温度（SST）的变化，从而防止超强厄尔尼诺现象仅通过热带太平洋动力学发展。我们的模型解释了 1972 年、1982 年和 1997 年大型厄尔尼诺现象的特征；然而，2015 年厄尔尼诺期间的较大 SST 异常可能是由强年代际变率增强的。