Seminar by Prof. Fei-Fei Jin from University of Hawaii

18 May 2023
KST 14:00 – 15:00

The Seminar is being held in Room 1010 (Jasmin) – Integrated mechanical engineering building. Click here for the campus map.

 The El Niño/Southern Oscillation (ENSO) phenomenon exhibits in its sea surface temperature anomalies and associated fields with complicated spatiotemporal variations.  Two main typical spatiotemporal patterns are known to be associated with the so-called the Central Pacific (CP) and Eastern Pacific (EP) El Niño events, which have significantly different longitudinal locations along the equator and temporal evolutions. This ENSO’s diversity has great implications for various impacts on global climate systems and beyond. Understanding this ENSO diversity has been a subject under extensive research activity, as its fundamental mechanisms remain a key open research subject. Using a revised intermediate coupled model, we demonstrate that deterministic nonlinear processes can generate realistic ENSO CP and EP diversity via either period doubling or subharmonic resonance routes or both to chaos.  The stochastic noise forcing may further expand the regime for this ENSO diversity.  Thus, the nonlinear instability of the ENSO oscillator  plays a fundamental role in its spatiotemporal diversity.   This nonlinear dynamics of ENSO should be further examined for better understanding ENSO’s predictability and ENSO’s sensitivity under global warming.