2025 Was the Third Hottest Year on Record, According to Europe’s Top Climate Experts

2025 was the third hottest year on record, according to a new report from Copernicus, Europe’s climate change service.

The past 11 years have been the 11th warmest on record—a concerning trend. 2024 currently remains the hottest year on record, and was the first year to see average global temperatures briefly exceed 1.5°C above pre-industrial levels.

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“It is a milestone that none of us wish to see,” Mauro Facchini, head of Earth Observation at the Directorate General for Defence Industry and Space at the European Commission, said in a press conference ahead of the announcement. “The news is not encouraging and the urgency of climate action has never been more important. By monitoring how our climate is changing, and the risk that these changes will bring, we can plan for a more climate resilient future.”

It is now understood that the world is likely expected to blow past the goal of limiting global warming to 1.5°C as agreed under the Paris Agreement. It’s largely not a question of if, but when. Researchers say it could occur far sooner than expected. Based on the current rate of warming, the world could reach this threshold for long-term global warming by the end of this decade—over a decade earlier than predicted when the agreement was adopted in 2015.

Read More: The World Is Failing Its 2025 Paris Agreement Target. Now What?

Last year saw lower temperatures in part due to La Niña conditions in the equatorial Pacific. While an El Niño event, as seen in 2023 and 2024, tends to cause global temperatures to rise, a La Niña event causes temperatures to cool slightly. Even so, as the report notes, 2025 was the warmest La Niña year on record.

Despite this cyclical ocean trend, global temperatures were still exceptionally warm. January 2025 was the warmest January on record, and several regions saw record high annual temperatures—the annual average temperatures reached their highest value on record in the Antarctic, and their second-highest in the Arctic. The northwestern and southwestern Pacific, the northeastern Atlantic, far eastern and northwestern Europe and central Asia also saw record-high annual temperatures.

Half of the global land area experienced “more days than average” of strong heat stress—defined as days with a “feels-like” temperature of 32°C (89.6°F) or above. In February, the combined sea ice cover from both poles fell to its lowest value since satellite observations began in the late 1970s.

The researchers stressed that the connection is clear—even if people don’t realize or acknowledge it. Countries around the world—including Türkiye, Japan, and Spain—saw record-breaking extreme heat last summer. An estimated 440 deaths are attributable to the Los Angeles wildfires in January, and more than 1,750 people were killed in December floods and landslides in southeast Asia. 2025 was also the second year on record that three category 5 storms formed over the Atlantic ocean. Climate change is making extreme weather disasters like these more likely.

“These long term trends aren’t how society experiences climate change,” said Samantha Burgess, strategic climate lead, at the European Centre for Medium-Range Weather Forecasts. “It is not through the trend in global temperatures, but through extreme weather events—and extreme events in 2025 had significant impacts on human health, ecosystems, and infrastructure.”

Even if the world were to stop emissions altogether, warming would be unavoidable, as CO2 can remain in the atmosphere for centuries. But every degree matters to help prevent worsening extreme weather events. 

“It’s essential to close the tap, but we know that the bath will continue to overflow,” says Laurence Rouil, director of Copernicus Atmosphere Monitoring Service. “So what we could say is that certainly there will be other years like [2025] in the future, even if we take action. But it shouldn’t prevent us [from taking] ambitious and urgent actions.”