Record-breaking El Niño supercharged by climate change, forecasts warn

Australia's Bureau of Meteorology delivered a stark forecast this week: the El Niño building across the Pacific is already shattering heat records and shows every sign of becoming the strongest on record. The ocean temperatures in the critical Niño 3.4 region—a band of equatorial Pacific water that meteorologists use to measure El Niño strength—have climbed to levels not seen since reliable measurements began in 1950. What makes this event particularly alarming is not just its intensity but its speed. Between February and July, sea surface temperatures in that region warmed by more than 2 degrees Celsius. No other period in the historical record has matched that rate of change over six months.

Felicity Gamble, a senior climatologist at the Bureau of Meteorology, laid out the numbers with precision. August's relative sea surface temperatures in the Niño 3.4 region are likely to reach between 2.2 and 2.3 degrees Celsius above average—higher than any August since records became reliable. The forecasts suggest the event could peak at over 3 degrees above average, surpassing the previous record of 2.6 degrees set in January 1983. "Not only is it strong, but it has escalated rapidly," Gamble said. "We could be seeing a record in terms of the strength, and also the rate of warming and the duration."

The United Nations weather agency weighed in on Thursday, warning that the El Niño would likely persist until early 2027 and carried "the potential to deliver a massive blow to communities and economies across the world." UN Secretary General António Guterres framed the moment starkly: "El Niño is being supersized before our eyes. The science leaves no room for doubt: the planet is in uncharted waters, and those waters are heating up."

But the record-breaking temperatures are not simply a product of natural climate cycles. Researchers at the University of Melbourne conducted preliminary analysis comparing historical climate patterns with and without the influence of greenhouse gas emissions. Their finding was sobering: climate change has made an El Niño event of this magnitude six times more likely than it would be in a world without human-caused warming. Dr. Andrew King, one of the study's co-authors, said the research pointed to "a climate change role here in the chance of having these extreme El Niño conditions." He added: "It seems likely there is a human fingerprint emerging in this event. We are seeing something that does not appear to have happened before and that is alarming." The study has been submitted for peer review but uses methodology consistent with other published climate research.

For Australia, El Niño typically means hotter and drier conditions across the south and east during winter and spring, raising the risk of heatwaves, drought, and bushfires. This past winter was already the third-warmest on record nationally, and the hottest on record for New South Wales, Tasmania, and Victoria. The Bureau's long-range forecast for September through November predicts below-average rainfall for the south and east, with temperatures likely to run above average south of the tropics. The western half of the continent is expected to see above-average rainfall.

The human toll is already visible beyond Australia's borders. In Papua New Guinea, the emerging El Niño is contributing to severe droughts that have triggered food and water shortages. Indonesia is experiencing major wildfires. Climate experts expect the El Niño to combine with ongoing climate change to push global temperatures to record highs through 2027. The event is forecast to peak in late spring or early summer, meaning the most intense phase lies ahead.