The European Union’s Copernicus Climate Change Service (C3S) says 2025 will almost certainly be the planet’s second- or third-warmest year on record, likely exceeded only by 2024’s record heat. The agency’s analysis follows a year marked by intense extremes and comes after last month’s COP30 summit, where governments failed to agree on major new emissions cuts amid geopolitical tensions and some backtracking on CO2-reduction policies.
C3S noted that 2025 is likely to complete the first three-year period with an average global temperature above 1.5°C compared with the 1850–1900 pre-industrial baseline. C3S strategic lead Samantha Burgess warned that such milestones are a sign of the accelerating pace of climate change.
Extreme weather struck many regions in 2025. Typhoon Kalmaegi killed more than 200 people in the Philippines, and Spain experienced its worst wildfires in three decades, events scientists say were made more likely by a warming climate. Although natural variability produces year-to-year temperature swings, the long-term trend is clear: rising global temperatures driven mainly by greenhouse gas emissions from burning fossil fuels.
Last year was the hottest on record, and the World Meteorological Organization has said the past decade contains the 10 warmest years since records began. The 1.5°C benchmark in the 2015 Paris Agreement remains the target nations pledged to try to avoid; while the world has not yet technically crossed that long-term threshold, the United Nations has said meeting the 1.5°C goal is no longer realistic without significantly faster cuts to CO2 emissions.
C3S temperature records go back to 1940 and are cross-checked with global datasets extending to 1850, providing the historical context for these recent temperature milestones.
