The EU’s Copernicus Climate Change Service reported that August was the hottest month ever recorded globally, with ocean temperatures also reaching unprecedented levels as western Europe capped its warmest summer.
In response, the United Nations warned that unless humanity reduces its reliance on fossil fuels, the planet will continue to plunge into uncharted climate extremes.
Copernicus observations date back to 1940, but scientists also draw on ice cores, tree rings and coral skeletons to place today’s warming against a far longer historical backdrop.
“Humans have not seen temperatures as hot as today for, arguably, at least the last 100,000 years,” said Samantha Burgess of the European Centre for Medium‑Range Weather Forecasts, which oversees Copernicus.
Global average air temperature in August stood at 16.96 °C—surpassing the previous record of July 2023 by 0.01 °C. Copernicus regards the two months as joint‑highest given the narrow margin.
Human activity, primarily the burning of coal, oil and gas, has warmed the planet by roughly 1.4 °C since pre‑industrial times, increasing the severity and likelihood of extreme weather events.
Yet heat‑trapping greenhouse‑gas emissions climbed to new highs in 2025.
“The evidence is irrefutable: this is the spiralling price of humanity’s fossil‑fuel addiction, and the global climate crisis it is fuelling,” said UN climate chief Simon Stiell of the Copernicus report.
– More ahead –
Global sea‑surface temperatures set new daily highs and tied for the hottest August on record, extending a three‑month streak of record‑breaking ocean warmth.
More than 90 % of the excess heat trapped by greenhouse gases has been absorbed by the oceans, sparing land from the worst warming but imposing severe costs on marine life, reefs and coastal communities.
Record heat struck overheated basins such as the Atlantic, the Mediterranean and the tropical Pacific, where the strongest El Niño of the modern era is rapidly intensifying.
These unusually warm Pacific waters raise the odds of extreme weather thousands of miles away, from floods in Peru to droughts in Africa and wildfires in Australia.
El Niño, a natural warm phase of a climate cycle, typically delivers a temporary spike in global temperatures on top of long‑term background warming.
Scientists anticipate further record‑breaking months as the “super” El Niño approaches peak intensity around December, with 2027—possibly 2026—poised to become the hottest years ever observed.
“Climate change makes every El Niño hotter, and until we stop burning coal, oil and gas these record‑shattering months will simply keep on coming,” warned climate scientist Friederike Otto of Imperial College London.
– Sizzling summer –
Copernicus also said that August marked the end of western Europe’s warmest summer, surpassing the long‑standing 2003 record.
The June‑to‑August season was dominated by severe, back‑to‑back heatwaves that shut schools, dried rivers and primed the land for devastating wildfires.
Between mid‑July and mid‑August, the EuroMomo monitoring platform estimated more than 32,000 excess deaths across Europe.
Scientists from the World Weather Attribution network concluded that a particularly strong heatwave in June would have been “virtually impossible” without the influence of climate change.
Extraordinary heat was felt worldwide: the contiguous United States endured its hottest summer on record, and regions home to about 900 million people experienced the hottest July ever observed, according to AFP analysis of Copernicus data.
“We’ve had an exceptional summer—not only in Europe, but other parts of the world where records that have existed for close to a century have fallen,” said Burgess, an ocean scientist and strategic lead at ECMWF. “The climate will continue to get more extreme unless we turn off the tap to global emissions,” she added.