A Nonlinear Mechanism for Decadal El Niño Amplitude Changes

نویسندگان

  • Axel Timmermann
  • Fei-Fei Jin
چکیده

[1] Based on the analysis of a low-order tropical atmosphere-ocean model we propose a nonlinear mechanism explaining several features of the observed El Niño-Southern Oscillation (ENSO) phenomenon: ENSO irregularity, ENSO Amplitude Modulations and decadal tropical climate variability. The mechanism suggested here is based on the idea of homoclinic/heteroclinic orbits, an inherently nonlinear concept. It turns out that this mechanism operates even in the presence of wind noise and is consistent with results from intermediate ENSO model simulations.

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تاریخ انتشار 2001