Webinar Details

Tiltle: ENSO and Tropical Basin Interactions: Conceptual Insights on Dynamics and Predictability

Speaker: Dr. Sen Zhao (University of Hawaiʻi at Mānoa, USA)

Date: November 4, 2025
Time: 04:00 UTC

- Save the link -

You can Sign up here or by QR code for reminders

You can watch the recording here.

Abstract:

Tropical sea surface temperature fluctuations are central to climate variability and predictability from seasonal to decadal timescales. Growing studies have highlighted the importance of tropical basin interactions (TBI) in modulating the El Niño–Southern Oscillation (ENSO) and other major climate modes, thereby contributing to their predictability. However, the quantitative influence of different ocean basins remains poorly constrained, partly due to limited observational records and systematic model biases. 

In this webinar, I will briefly review fundamental dynamics of ENSO and other tropical modes of variability through a hierarchy of conceptual frameworks. I will then present a newly developed eXtended nonlinear Recharge Oscillator (XRO) model which parsimoniously incorporates the core ENSO dynamics and ENSO’s seasonally modulated interactions with other tropical climate modes. The XRO framework enables quantification of TBI’s influence on the dynamics, variability, and predictability of ENSO and other climate modes in a unified framework. I will also demonstrate how different XRO experiment techniques—including decoupled experiments, pacemaker experiments, and pacemaker hindcast experiments that mimic GCM experiments—can provide distinct insights on TBI’s role on ENSO’s variability and predictability. Finally, I will also discuss how biases in climate models affect ENSO–TBI relationships and limit their predictive accuracy.