J. David Neelin, David S. Battisti, Anthony C. Hirst, Fei-Fei Jin,
Yoshinobu Wakata, Toshio Yamagata, and Stephen Zebiak
J. Geophys. Res., 1998. Paper (PDF 11 MB)
© Copyright 1998 by the American Geophysical Union.
Abstract. Beginning from the hypothesis by Bjerknes that ocean-atmosphere interaction was essential to ENSO, the TOGA decade has not only confirmed this but supplied detailed theory for mechanisms setting the underlying period, and possible mechanisms responsible for the irregularity of ENSO. Essentials of the theory of ocean dynamical adjustment are reviewed from an ENSO perspective. Approaches to simple atmospheric modeling greatly aided development of theory for ENSO atmospheric feedbacks, but are critically reviewed for current stumbling blocks for applications beyond ENSO. ENSO theory has benefitted from an unusually complete hierarchy of coupled models of various levels of complexity. Most of the progress during the ENSO decade came from models of intermediate complexity, which are sufficiently detailed to compare to observations and to use in prediction, but are less complex than coupled general circulation models. ENSO theory in simple models lagged behind ENSO simulation in intermediate models, but has provided a useful role in uniting seemingly diverse viewpoints. The process of boiling ENSO theory down to a single consensus model of all aspects of the phenomenon is still a rapidly progressing area, and theoretical limits to ENSO predictability are still in debate, but a thorough foundation for the discussion has been established in the TOGA decade.
Citation. Neelin, J. D., D. S. Battisti, A. C. Hirst, F.-F. Jin, Y. Wakata, T. Yamagata, S. Zebiak, 1998: ENSO Theory. J. Geophys. Res., 103(C7), 14261-14290.
Acknowledgments Preparation of this review was supported in part by National Science Foundation grant ATM-9521389 and National Oceanic and Atmospheric Administration grant NA46GP0244.