August was the hottest single month ever recorded globally, with ocean temperatures also reaching unprecedented highs as western Europe capped its warmest summer, according to the European Union’s Copernicus Climate Change Service.
Global Temperatures and the Record-Breaking Summer
Global average air temperatures in August reached 16.96C surpassing by 0.01C the previous all-time monthly record set in July 2023. Copernicus said it considered the two months joint-highest given the narrow difference. Copernicus observations go back to 1940, but other evidence — such as ice cores, tree rings and coral skeletons — allow scientists to place today’s climate against a much longer historical context.
Humans haven't seen temperatures as hot as today for, arguably, at least the last 100,000 years,
Samantha Burgess from the European Centre for Medium-Range Weather Forecasts, which oversees Copernicus, told AFP.
Scientists say that human activity — primarily the burning of coal, oil and gas — has warmed the planet by roughly 1.4C since pre-industrial times and increased the severity and likelihood of extreme weather. Yet heat-trapping greenhouse gas emissions rose to new highs in 2025.
Ocean Heatwaves and the Rising El Nino
Global sea surface temperatures also set a new daily high and tied equal-hottest for August, extending a three-month streak of record-breaking warmth across the world’s oceans. More than 90 percent of excess heat trapped by greenhouse gas emissions has been absorbed by the oceans, sparing land from warming but at severe cost to marine life, reefs and coastal communities. Records tumbled in overheated basins like the Atlantic and Mediterranean and also the tropical Pacific, where the strongest El Nino weather pattern in the modern era is fast accumulating strength.
These events are marked by unusually warm Pacific waters but raise the odds of wild weather thousands of miles away, from floods in Peru to droughts in Africa and wildfires in Australia. The warmer phase of a natural climate cycle, El Nino episodes usually deliver a temporary spike in global temperatures already elevated by long-term background warming. The one currently being experienced is still strengthening and could become one of the most powerful on record, according to the Copernicus team.
Scientists expect records to keep falling in the months ahead as this “super” El Nino approaches peak intensity around December and for 2027 — and maybe even 2026 — to become the hottest years ever observed.
Europe’s Exceptional Summer and Human Toll
Copernicus also said that August marked the end of western Europe's warmest summer
that surpassed the long-standing record set in 2003. The June to August season was defined by severe, back-to-back heatwaves that shut schools, dried up rivers and primed the land for devastating wildfires.
Between mid-July and mid-August, the continent’s EuroMomo monitoring platform estimated that Europe saw more than 32,000 excess deaths. 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.
On Wednesday, the National Oceanic and Atmospheric Administration said the contiguous United States has endured its hottest summer on record. And regions home to around 900 million people lived through the hottest July ever observed, according to AFP analysis of Copernicus data.
International Warnings on Fossil Fuel Emissions
In response to the assessment by the Copernicus Climate Change Service, the UN warned that until humanity weaned off fossil fuels, the planet would only push deeper into uncharted territory.
The evidence is irrefutable: this is the spiralling price of humanity's fossil fuel addiction, and the global climate crisis it is fuelling,
United Nations climate chief Simon Stiell said of the Copernicus report.
Dr Samantha Burgess, strategic lead for climate at Copernicus, described August as a remarkable month in the global climate record
, and its impacts had been increasingly being felt by communities, economies and ecosystems across the world
. 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 for at ECMWF. The climate would continue to get more extreme unless we turn off the tap to global emissions
, she added.
Climate change makes every El Nino hotter, and until we stop burning coal, oil, and gas these record-shattering months will simply keep on coming, Friederike Otto
What Lies Ahead for Global Climate Records
The biggest impact of this natural phenomenon on global temperatures is expected to hit over the coming year, meaning the current run of records may have further to go. With heat-trapping greenhouse gas emissions rising to new highs in 2025 and the strongest El Nino in the modern era fast accumulating strength, scientists warn that meteorological records will likely continue to tumble as the super El Nino approaches peak intensity around December.
