Earth's heat accumulation accelerates, UN warns as Cop31 opens in Turkey

The UN's weather agency reported that heat is accumulating in Earth's systems at an accelerating rate as the Cop31 climate summit begins in Turkey, with 2026 on track to be one of the four warmest years on record. The energy imbalance between incoming and outgoing solar radiation reached its highest level since monitoring began. The World Meteorological Organization said this imbalance will supercharge extreme weather events like heatwaves, droughts, and tropical cyclones. Average surface temperatures from January to September 2026 were about 1.47C above preindustrial levels, with record ocean heat and sea levels, as the ocean absorbs 90% of excess heat trapped by greenhouse gases. UN Secretary General António Guterres warned of a "new age of climate extremes," citing a supersized El Niño colliding with manmade warming. Atmospheric carbon dioxide reached 426.8 ppm in 2025, up from 356.42 ppm in 1992, and Antarctic sea ice hit its third-lowest annual maximum in 2026.