Special Seminar: ENSO transitions and projected changes
The diverse nature of El Niño-Southern Oscillation (ENSO) events complicates the understanding of tropical ocean-atmosphere interactions. Transitions between different ENSO types—those peaking in the Eastern Pacific (EP) and Central Pacific (CP)—are shaped by various factors, many of which are expected to evolve under climate change. In this study, we evaluate ENSO transitions using observational data and climate model projections, focusing on how the starting ENSO phase influences transition probabilities. Our findings reveal that transitions to CP El Niño events are more common than those to EP events, except from a neutral state. Additionally, El Niño events generally occur as isolated events, while La Niña events can persist in successive years. Notably, EP-type ENSO events do not repeat in back-to-back years. Several transitions appear to be driven by internal dynamics, such as neutral conditions to El Niño, CP El Niño to another El Niño, and CP La Niña to CP El Niño or La Niña. Projections under a high-emission scenario suggest a shift in ENSO dynamics, with CP El Niño events becoming more frequent, while EP La Niña events decline. These changes are expected to emerge by mid-century, with some patterns intensifying by the end of the 21st century.
Datum
15.10.2025
Uhrzeit
10:00 h
Ort
- DKRZ room 034
- Hamburg