A potentially historic El Niño is forming across the Pacific, with the National Oceanic and Atmospheric Administration estimating a 69 percent chance that the October–December 2026 season could surpass every event recorded since 1950. Sea-surface temperatures in the key Niño 3.4 zone reached +2.7 °C above average in mid-August, and Zeke Hausfather of Berkeley Earth warned it could be the strongest in 500 to 1,000 years. The German Weather Service and the Met Office both anticipate an unprecedented event, prompting the Panama Canal Authority to reduce ship transit bookings from September.
Amid the forecasts, researchers at the University of California, San Diego published findings in Science Advances suggesting marine cloud brightening (MCB) could weaken El Niño. Climate simulations of the 2015–16 event showed that nine months of MCB lowered sea-surface temperatures by 1.88 °C compared with no intervention, though the technique also raised temperatures in parts of Europe and Asia.