Global warming reaches 1.4C after third-hottest year on record

BRUSSELS — The world is rapidly closing in on the 1.5 degrees Celsius warming limit that serves as a threshold for ever more dangerous climate change, European scientists have warned. 

Average global temperatures are now around 1.4C higher than during the pre-industrial era, according to data released Wednesday by the European Union’s Copernicus planetary observation service. The scientists also found that 2025 was the third-hottest year on record.

If this warming trend continues, temperatures will breach the 1.5C limit set out in the Paris Agreement before the end of this decade. In the 2015 landmark climate accord, governments pledged to limit global warming to “well below” 2C and ideally to 1.5C. 

The threats from climate change, such as more intense heat waves and rising sea levels, increase with every tenth of a degree of warming. Scientists also warn that passing 1.5C risks triggering so-called tipping points, from rainforest diebacks to ocean circulation collapse, that bring about irreversible and extreme climatic changes. 

In theory, the world could return to 1.5C after crossing it by using technology to remove vast amounts of carbon dioxide from the atmosphere, a scenario known as “overshoot.” This technology, however, is not yet available at the scale required.

“With the 1.5C in the terms of the Paris Agreement around the corner, now we are effectively entering a phase where it will be about managing that overshoot,” Carlo Buontempo, director of the Copernicus Climate Change Service, told reporters at a press conference.

“It’s basically inevitable that we will pass that threshold, and it’s up to us to decide how we want to deal with the enhanced and increased higher risk that we will face as a consequence of this,” he said. The longer and greater the overshoot, the bigger the risk, he added.

The hottest year — and the only one so far to exceed the 1.5C threshold — remains 2024 with 1.6C. However, the Paris Agreement targets refer to long-term trends rather than those lasting a few years, and Buontempo said three different Copernicus models, including five-year averages and 30-year linear trends, showed warming has now reached around 1.4C. 

Copernicus data shows that 2025 was the third-warmest year on record at 1.47C above pre-industrial levels, just marginally cooler than 2023. That’s despite El Niño, a naturally occurring climate pattern that tends to bring hotter temperatures on top of the human-induced warming, ending in mid-2024 and a cooling La Niña phase emerging late last year.

“The last three years in particular have been extremely warm compared to earlier years,” said Samantha Burgess, deputy director at Copernicus. Taken together, she noted, the three-year period exceeded 1.5C, something that had not occurred before. 

“The primary reason for these record temperatures is the accumulation of greenhouse gases in the atmosphere, dominated by the burning of fossil fuels,” Burgess said. “As greenhouse gases continue to accumulate in the air, temperatures continue to rise, including in the ocean; sea levels continue to rise, and glaciers, sea ice and ice sheets continue to melt.” 

For the European continent, 2025 also marked the third-warmest year on record, the data shows. Hot and windy conditions contributed to record wildfires, resulting in Europe’s worst fire-related emissions since monitoring began 23 years ago.

Half the world experienced an above-average number of days causing strong heat stress, meaning temperatures that feel like 32C or more. Burgess added that some regions — including most of Australia, parts of Northern Africa and the Arabian Peninsula — saw more days with extreme heat stress, when perceived temperatures reach dangerous levels above 46C.

“The summers we are facing now are very different to the summers that our parents experienced, very different to the summers that our grandparents experienced,” Burgess said. “Children today will be exposed to more heat hazards and more climate hazards than perhaps we were or our parents were.”

The polar regions saw significantly higher temperatures in 2025, with the Antarctic experiencing its hottest year and the Arctic its second-warmest year on record. 

Accordingly, the expanse of polar sea ice was below average throughout the year, and in February 2025 briefly hit a record low since monitoring began in the 1970s. The shrinking of the ice caps accelerates global warming by reducing the amount of sunlight reflected back into space. 

European science officials also expressed concern about the Trump administration’s climate science cuts and erasure of datasets. 

“Data and observations are obviously central to our efforts to confront climate change … and these challenges don’t know any borders,” said Florian Pappenberger, director of the European Centre For Medium-Range Weather Forecasts, which oversees Copernicus. “Therefore, it is of course concerning that we have an issue in terms of data.” 

Hanne Cokelaere contributed to this report.