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arXiv · 1511.07472

Mixed mode oscillations of the El Niño-Southern Oscillation

Abstract

Very strong El Niño events occur sporadically every 10-20 years. The origin of this bursting behavior still remains elusive. Using a simplified 3-dimensional dynamical model of the tropical Pacific climate system, which captures the El Niño-Southern Oscillation (ENSO) combined with recently developed mathematical tools for fast-slow systems we show that decadal ENSO bursting behavior can be explained as a Mixed Mode Oscillation (MMO), which also predicts a critical threshold for rapid amplitude growth. It is hypothesized that the MMO dynamics of the low-dimensional climate model can be linked to a saddle-focus equilibrium point, which mimics a tropical Pacific Ocean state without ocean circulation.

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BibTeXRIS

Andrew Roberts, Esther Widiasih, Axel Timmermann, Christopher K. R. T. Jones, John Guckenheimer. 2016-01-28. Mixed mode oscillations of the El Niño-Southern Oscillation. https://doi.org/10.1175/jas-d-15-0191.1

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