ENSO regimes: Reinterpreting the canonical and Modoki El Niño

  title={ENSO regimes: Reinterpreting the canonical and Modoki El Ni{\~n}o},
  author={K. Takahashi and Aldo Montecinos and Katerina Goubanova and Boris Dewitte},
  journal={Geophysical Research Letters},
We propose that the first two empirical orthogonal function (EOF) modes of tropical Pacific sea surface temperature (SST) anomalies do not describe different phenomena (i.e., El Niño‐Southern Oscillation (ENSO) and “El Niño Modoki”) but rather the nonlinear evolution of ENSO. We introduce two new uncorrelated indices (E and C), based on the leading EOFs, that respectively account for extreme warm events in the eastern and cold/moderate warm events in the central equatorial Pacific… 

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