August was the world’s joint hottest month on record, with global temperatures 1.65 degrees above pre-industrial times, scientists have said.
Last month tied with July 2023 for the hottest calendar month in the temperature records, as well as the hottest August ever recorded for the world, scientists from the European Union’s Copernicus Climate Change Service said.
Western Europe has experienced its warmest summer on record, surpassing the previous record set in 2003, Copernicus said.
Heatwaves in August continued a run of extreme heat that began in May, severe drought conditions have hit the UK, France, Hungary, Romania and Serbia, and major rivers from the Rhine and Danube to the Dnieper experienced exceptionally low flows, the Copernicus scientists said.
Globally the month was 1.65 degrees above the estimated average for the period 1850-1900, a time before humans began burning fossil fuels at scale – releasing greenhouse gases that will continue to further heat the planet until emissions are brought to zero overall, which is known as net zero.
The scientists said August marked a return to temperatures above a key threshold of 1.5 degrees higher than pre-industrial averages, the first time they have breached the figure since November 2025.
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Under 2015’s global Paris Agreement, countries agreed to limit global warming in the long term to “well below” 2 degrees above pre-industrial levels and pursue efforts to curb them to 1.5 degrees to prevent the worst droughts, heatwaves, floods, sea level rises and wildlife collapses driven by climate change.
Last month also saw sea surface temperatures reach record highs, as a result of global heating from burning fossil fuels and rapidly warming seas in the Pacific associated with the strong El Nino weather phenomenon, the scientists said.
Sea surface temperatures away from the polar regions were the highest on record for August, at 21.07 degrees, and the joint highest on record across all months with March 2024.
Samantha Burgess, strategic lead for climate at ECMWF, said: “August 2026 was a remarkable month in the global climate record.
“It was both the warmest August and the warmest month ever recorded, with global temperatures reaching 1.65 degrees above pre-industrial levels, marking the return of global temperatures above 1.5 degrees.
“Combined with record global sea surface temperatures and the warmest summer on record for western Europe, these observations show how climate change is driving extremes across both the atmosphere and the oceans.
“The impacts of these conditions are increasingly being felt by communities, economies and ecosystems across the world.”
Prof Friederike Otto, professor of climate science at Imperial College London, said: “I run the risk of sounding like a broken record, but these numbers should surprise no one.
“You don’t need to be a climate scientist to see the evidence of climate change, you just need to look out of your window.
“While El Nino is starting to ramp up the heat, the underlying driver remains our relentless burning of fossil fuels.
“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,” she said. – PA