A recent study published in Science warns that the world’s most powerful El Niño events are becoming markedly stronger as a result of human‑caused climate change. Researchers examined coral records from the Galápagos Islands spanning roughly 900 years and found that El Niño strength has increased by more than 36% since the mid‑1800s, with a 16% rise in just the last four decades.
How the researchers measured past El Niños
Lead author Julia Cole, a paleoclimate scientist at the University of Michigan, used the chemical composition of coral skeletons—specifically calcium‑strontium ratios, oxygen isotopes, and uranium‑thorium dating—to reconstruct historic sea‑surface temperatures. By comparing these ancient temperature signals with modern instrumental records, the team identified a clear upward trend that mirrors the rise in global temperatures driven by fossil‑fuel emissions.
Implications for weather worldwide
El Niño events, which are temporary warmings of the central equatorial Pacific, influence weather patterns across the globe. Stronger El Niños can intensify heat waves, trigger severe floods in some regions, and deepen droughts in others, potentially costing trillions of dollars in damage. The current super El Niño, which began a few months ago, is projected to become the strongest on record, with sea‑surface temperatures already 2.7 °C (4.9 °F) above normal.
Scientific debate continues
While many climate scientists view the findings as further evidence that global warming amplifies natural climate variability, some experts remain skeptical. University of Pennsylvania climatologist Michael Mann and University of North Carolina marine scientist John Bruno argue that recent instrumental data from the Galápagos show a decline in El Niño‑related temperature variations, suggesting the coral record may reflect broader greenhouse‑gas warming rather than a true shift in El Niño behavior.
Nevertheless, the consensus among the study’s authors is clear: “It raises the specter of a future where larger El Niño and La Niña events dial up the pace and severity of weather extremes,” said Brown University coral scientist Kim Cobb, who was not involved in the research.
What this means for policy
The authors stress that the findings add urgency to efforts to reduce fossil‑fuel emissions. “There isn’t a magic bullet that will slow El Niños down,” Cole said. “Getting off fossil fuels remains the most effective way to limit further intensification.”
As the super El Niño continues to develop over the next two to four months, forecasters at Columbia University’s El Niño tracker will monitor its progression, warning communities to prepare for heightened weather risks.
Original reporting: WLWT Cincinnati — read the source article.
