This year is set to be the world’s second- or third-warmest on record, likely surpassed only by 2024’s record-breaking heat, the European Union’s Copernicus Climate Change Service (C3S) said.
The data follows last month’s COP30 climate summit, where governments failed to agree on substantial new measures to cut greenhouse gas emissions amid strained geopolitics, a US rollback of efforts and moves by some countries to weaken CO2-reduction policies. C3S said 2025 will probably complete the first three-year period in which the average global temperature exceeded 1.5°C above the 1850–1900 pre-industrial baseline.
“These milestones are not abstract – they reflect the accelerating pace of climate change,” said Samantha Burgess, strategic lead for climate at C3S.
Extreme weather affected regions worldwide in 2025. Typhoon Kalmaegi killed more than 200 people in the Philippines last month, and Spain suffered its worst wildfires in three decades in conditions scientists said were made more likely by climate change.
Last year was the planet’s hottest on record. While natural variability causes year-to-year fluctuations, long-term global temperatures show a clear warming trend driven primarily by greenhouse gas emissions from burning fossil fuels. The World Meteorological Organization earlier said the last 10 years have been the 10 warmest since records began.
The 1.5°C threshold in the 2015 Paris Agreement is the limit countries pledged to try to avoid to prevent the worst impacts of warming. Although the world has not yet technically breached that long-term threshold, the UN has said the 1.5°C goal can no longer realistically be met and urged faster CO2 cuts to limit overshoot.
C3S’s records extend back to 1940 and are cross-checked with global temperature datasets reaching back to 1850.
