Recent strengthening of eastern Pacific ENSO in the last millennium paleorecord.

Recent coral records show a significant increase in eastern Pacific ENSO variability over the last millennium, exceeding simulated natural variability and linked to stronger El Niño events.

• Why it matters: Understanding how ENSO responds to climate warming is crucial because it influences global climate extremes, yet current data and models are limited and uncertain.
• What they did: Researchers analyzed coral skeleton geochemistry from the Galápagos and central Pacific over the past millennium, revealing a large recent increase in sea surface temperature variability.
• The result: The findings suggest that recent ENSO variability exceeds natural fluctuations and may intensify climate extremes, providing important long-term context for future climate risk assessments.