Copernicus: September 2026 second-warmest on record, oceans at record heat

September 2026 was the second-warmest September on record, with an average surface air temperature of 16.27 °C, the Copernicus Climate Change Service said. That is 0.82 °C above the 1991–2020 average and 1.63 °C above pre-industrial levels.

Sea-surface temperature between 60°S and 60°N reached 21.05 °C, a September record, above 20.92 °C in 2023. Antarctic winter maximum sea ice was the third lowest on record, and Arctic ice in September was about ten percent below average.

"Crossing the Paris Agreement's long-term limit is only a matter of time," said Carlo Buontempo, director of the Copernicus Climate Change Service.