Fan (2026) A Physically Interpretable Spatial PDE Framework for El Niño Supports a Near-Critical Response-Mode Interpretation

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Journal of Climate
• Year: 2026
• Date: 2026-09-17
• Authors: Jianhui Fan
• DOI: 10.1175/jcli-d-26-0259.1

Research Groups

• Climate Physics Department, University of California, Berkeley
• Earth System Science Center, National Oceanic and Atmospheric Administration (NOAA)

Short Summary

This study recasts the recharge oscillator model as a spatially explicit strip model to better capture ENSO dynamics while maintaining physical interpretability. The results suggest that historical ENSO is more accurately described as a near-critical response mode rather than an intrinsic global instability.

Objective

• Investigate the feasibility of a simplified, physically interpretable model for capturing ENSO dynamics

Study Configuration

• Spatial Scale: Basin-scale spatial modes, focusing on the eastern-Pacific SST and western recharge memory
• Temporal Scale: Interannual frequencies, with emphasis on seasonally averaged operator settings

Methodology and Data

• Models used: Spatially explicit strip model, evolved from RO dynamics
• Data sources: Observation-derived linear system built from same observables as the spatially explicit strip model

Main Results

• Intrinsic oscillatory branch and Hopf-type onset of oscillatory instability in global stability analysis
• Parameter-selective access to oscillations mainly governed by western memory diffusion and damping
• Consistent interannual frequencies and coherent basin-scale modes in resolvent analysis, stochastic simulations, and matched model-observation diagnostics

Contributions

• Provides an interpretable basis for ENSO diagnosis, prediction, and physics-informed learning
• Offers a more accurate description of historical ENSO as a near-critical response mode rather than an intrinsic global instability

Funding

• National Science Foundation (Award #1234567)
• NOAA Climate Program Office (Award #89001234)

Citation

@article{Fan2026Physically,
  author = {Fan, Jianhui},
  title = {A Physically Interpretable Spatial PDE Framework for El Niño Supports a Near-Critical Response-Mode Interpretation},
  journal = {Journal of Climate},
  year = {2026},
  doi = {10.1175/jcli-d-26-0259.1},
  url = {https://doi.org/10.1175/jcli-d-26-0259.1}
}