James Hansen, a prominent climate scientist at Columbia University, has predicted that 2026 will become the hottest year on record, surpassing 2024 due to accelerating global warming and an impending super El Niño. He argues that current sea surface temperatures support this forecast despite ongoing La Niña cooling. Other experts urge caution amid forecast uncertainties.
James Hansen, who testified to the US Congress in 1988 about human-caused global warming, stated in a recent blog post with colleagues that 2026 will break the temperature record set by 2024. That year saw global temperatures exceed 1.5°C above pre-industrial levels for the first time. “That margin is wide enough that we are willing to make the prediction that 2026 will be the warmest year,” they wrote, noting sea surface temperatures are now 0.17°C warmer than in 2023, compared to 0.11°C in 2024. “Of course, 2027 will be still hotter,” they added. The second half of 2026 is expected to see the start of a powerful El Niño phase, potentially the strongest on record, as warm water expands across the equatorial Pacific Ocean, heating the planet further. Current La Niña conditions have kept the first three months of 2026 about 0.1°C cooler than the same period in 2024 on average. Zeke Hausfather at Berkeley Earth projected 2026 at 1.47°C above pre-industrial levels, second-warmest on record, while a 30 April blog post by Hausfather gave it a 26 percent chance of being hottest and 56 percent for second. Other scientists express reservations. Adam Scaife at the UK Met Office noted uncertainty, with their December forecast ranging from 1.34°C to 1.58°C above pre-industrial averages, short of 2024's 1.55°C. “Nobody can be 100 per cent confident,” Scaife said. John Kennedy at the World Meteorological Organization described Hansen’s forecast as one method among many. Scaife acknowledged Hansen's concern that warming rates exceed models, possibly indicating higher climate sensitivity to CO2. An El Niño on top of record warming is set to heighten risks of heatwaves, droughts, and wildfires in regions like Australia, South-East Asia, central and southern Africa, India, and the Amazon.