ENSO diversity shows robust decadal variations that must be captured for accurate future projections

Dieppois, Bastien; Capotondi, Antonietta; Pohl, Benjamin; Chun, Kwok Pan; Monerie, Paul Arthur; Eden, Jonathan

Abstract

El Niño-Southern Oscillation (ENSO) shows a large diversity of events that is modulated by climate variability and change. The representation of this diversity in climate models limits our ability to predict their impact on ecosystems and human livelihood. Here, we use multiple observational datasets to provide a probabilistic description of historical variations in event location and intensity, and to benchmark models, before examining future system trajectories. We find robust decadal variations in event intensities and locations in century-long observational datasets, which are associated with perturbations in equatorial wind-stress and thermocline depth, as well as extra-tropical anomalies in the North and South Pacific. Some climate models are capable of simulating such decadal variability in ENSO diversity, and the associated large-scale patterns. Projections of ENSO diversity in future climate change scenarios strongly depend on the magnitude of decadal variations, and the ability of climate models to reproduce them realistically over the 21st century.

• Journal Article Type: Article
• Acceptance Date: Sep 21, 2021
• Online Publication Date: Oct 7, 2021
• Publication Date: Dec 1, 2021
• Deposit Date: Jan 18, 2022
• Publicly Available Date: Jan 19, 2022
• Journal: Communications Earth and Environment
• Electronic ISSN: 2662-4435
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 2
• Issue: 1
• Article Number: 212
• DOI: https://doi.org/10.1038/s43247-021-00285-6
• Public URL: https://uwe-repository.worktribe.com/output/8545645