El Niño stronger than in 1,000 years, study finds

A study analyzing fossilized corals from the Galapagos Islands has revealed that El Niño events in the eastern Pacific are now more intense than at any point in the last millennium. The research, published in Science, suggests this intensification is linked to human-caused global warming.

Researchers reconstructed a thousand-year ocean surface temperature record by examining the chemistry of fossilized corals. They found that temperature variability since 1984 is 36.5% higher than during the preindustrial period (1000-1850 CE) and that warmer El Niño events have become significantly stronger. This finding contrasts with climate models that only incorporated natural factors, which did not show such a pronounced increase in ENSO variability.

The study's authors attribute the current ENSO intensification to human activity, specifically the use of fossil fuels. They note that global warming is already expected to worsen the hydrological impacts of El Niño, leading to more extreme floods and droughts, and that the strengthening of temperature swings compounds these effects. The researchers also observed that the faster emergence of this trend in the eastern Pacific aligns with climate model predictions for human-caused changes.