El Niño could unleash ocean heat that sends 2026 into record-breaking territory

This summer's heat is human caused, not from El Niño – but the climate phenomenon is set to release pent-up ocean heat. Wildfires are burning in North America and Europe. Deadly heatwaves are suffocating cities and the world's oceans are the hottest ever recorded for this time of year. A strengthening El Niño is forecast to be off-the-charts, spiking global temperatures and warping weather all over. While it may seem like the planet is baking through a record-shattering summer from hell, it's not quite in record territory – yet. So far this is only the third-hottest year, behind 2024 and 2025, climate statistics show. But give 2026 time. Due to accelerated human-caused global warming and a supersized El Niño, there's an increasing chance that by the end of the year, 2026 could become the hottest year on record, eclipsing 2024 – or at least come close, scientists say. Even if this year sets the record, it won't last long. Although scientists disagree on whether 2026 will be the hottest year on record, they agree on it being a near lock that 2027 will beat out any modern year for heat, maybe by a great deal. With wars around the globe in the last few years, people didn't pay much attention to climate change "because the world was on fire in different ways. The world is now on fire again with climate change in a way that’s increasingly difficult to ignore,” says climate scientist Zeke Hausfather of climate data nonprofit Berkeley Earth. “It's going to keep getting worse.'' Increasing odds for a record hot year Hausfather calculates there's a 35 per cent chance that 2026 will pass 2024 as the hottest year on record. But Hausfather keeps increasing those odds nearly every month – up from only seven per cent in March. Former top NASA climate scientist James Hansen, often called the godfather of climate science for 40 years of accurate long-term warnings, predicts that 2026 will edge out 2024 at the end of the year. The world's daily sea surface temperature tied 2024 starting in May, and since June it's been record hot nearly every day. With oceans covering more than 70 per cent of the globe's surface, there's generally a month-and-a-half lag between heat showing up in oceans and then being reflected in the global average temperature, Hansen says. So it's about time that the entire globe starts shattering records, he says. About 82 per cent of the world's ocean surface is overheated with marine heatwaves this year, according to Europe's Copernicus climate service. About a month ago the US National Oceanic and Atmospheric Administration forecast that there was a 66 per cent chance that 2026 would be the fourth hottest and only a 0.1 per cent chance it would be number one for warmth by year's end. NOAA monitoring chief Russell Vose says those odds will be rising when NOAA finishes its analysis from July. Hausfather says what's changing outlooks is the increasingly strong forecasts for a “mind-numbing” record-setting El Niño. El Niño is a natural temporary warming of parts of the equatorial Pacific that heats up the globe's average temperature and warps weather extremes across the planet. Most forecasts have El Niño becoming the strongest in history. El Niños always release pent-up heat in the ocean, but because of greenhouse gases trapping heat and 90 per cent of it going into the world's seas, there's more heat to release, says Zachary Labe, a climate scientist at Climate Central, a science and communications nonprofit. The amount of heat in the world's oceans – a marker of human-caused climate change – keeps setting new record highs, Labe says. This summer's heat is human caused, not from El Niño Climate scientists say what we've seen this summer can't be blamed on El Niño because its impacts really don't kick in for a few more months. The fires, heat and extremes that have dominated the summer of 2026 are what scientists have long been warning about from the burning of coal, oil and gas. “The driver of the record warmth is climate change in the background. And it’s a much larger – much, much larger – contribution than El Niño, which is just a tenth to two-tenths of a degree on top of that long-term trend,” Labe says. That warming is accelerating, Hansen says. That's because traditional industrial pollution that creates soot and smog – which cool the planet and mask greenhouse gas-triggered warming – is decreasing, Hansen says. Also, it looks as if the climate might be reacting to greenhouse gases stronger than scientists anticipated, he says. Heatwaves keep hitting This summer’s heatwaves have hit hard in places where people aren’t used to extreme heat, unlike in the tropics, climate scientists say. And they've been especially noticeable at night, making it hard for people to sleep, which impairs their health and their ability to be productive at work, says Samantha Burgess, global strategic lead at Copernicus climate service. She points to Europe, where there was an “exceptional” heatwave in May, another in June, two in July and another one going on now in France and Spain. “European heatwaves are not in isolation. So there’s also been shocking heatwaves in North America. There’s been shockingly hot conditions in South America as well. There’s been devastating heatwaves in India,” Burgess says. “There’s always heatwaves somewhere in the world sometime, but what is very unusual for Europe for this particular year is the frequency and extent of the heatwaves.” Princeton University climate scientist Michael Oppenheimer says this is what scientists have long been warning about. "These are vivid pictures of not just the future, which is what we used to say, but on the whole of what climate change is doing. There’s no question that climate change has increased the risk of wildfires. There’s no question that the climate change increased the probability of really hot, nasty, even unprecedented summers around the world.”