The world has just recorded its warmest October on record, and 2026 is now virtually certain to become only the second calendar year to average more than 1.5°C above pre-industrial levels, the EU’s Copernicus Climate Change Service said on Friday.
October’s average global surface air temperature was 1.75°C above the pre-industrial average, making it the warmest October in the record and the third month in a row above the 1.5°C mark. The month’s average temperature was 15.35°C. Sea surface temperatures outside the polar regions reached 20.95°C, the highest on record for October, beating the previous record set in 2023.
Copernicus said 2026 was most likely to end as the second-warmest year on record, with about a 20 per cent chance of tying or exceeding 2024, currently the warmest year. There is about an 80 per cent chance the year ranks second-warmest. The four-year average for 2023 to 2026 is also expected to exceed 1.5°C.
“An exceptionally strong El Niño is adding further heat to a climate already warmed by human activities, while 2026 is on track to become the second calendar year above 1.5°C,” said Samantha Burgess of the European Centre for Medium-Range Weather Forecasts, which operates Copernicus. “Particularly significant is that the four-year average is also expected to exceed 1.5°C, highlighting how sustained this period of global warmth has become.”
The Paris Agreement target refers to a long-term average, so a single year above 1.5°C does not formally breach it. But the United Nations now officially assumes the target will be overshot, and scientists warn that the risks of climate extremes and dangerous tipping points intensify with every fraction of a degree. Climate scientist Johan Rockström, director of the Potsdam Institute for Climate Impact Research, has said the overshoot should be kept as small and short as possible, and that it is now unavoidable that warming will officially exceed 1.5°C within the next five years.
The findings land three days before the COP31 climate summit opens in Antalya, Türkiye, on Monday, after a year marked by deadly floods in Nepal, searing heatwaves in Europe and major wildfires in Indonesia. 2024 was the first calendar year to average above 1.5°C; 2026 is set to be the second.
Sources: Reuters, “After warmest October on record, 2026 is likely to exceed 1.5 C above pre-industrial level, says EU climate service” (https://www.reuters.com/sustainability/cop/after-warmest-october-record-2026-is-likely-exceed-15-c-above-pre-industrial-2026-11-06/); Copernicus Climate Change Service, October 2026 monthly bulletin.
