Copernicus Data Confirms 2025 as Third Warmest Year, Sustaining 1.5°C Breach

The Copernicus Climate Change Service (C3S), part of the European Centre for Medium-Range Weather Forecasts (ECMWF), released its January 2026 analysis confirming that 2025 ranked as the third warmest year globally on record. This data highlights a sustained warming trajectory, as the three-year period spanning 2023 through 2025 marks the first time the annual average temperature surpassed the critical 1.5°C benchmark relative to pre-industrial levels (1850–1900) for a continuous duration. The temperature anomaly for 2025 was recorded at 1.47°C above the pre-industrial baseline, placing it marginally cooler than 2023, but below 2024, which remains the warmest year on record with an anomaly of 1.60°C.

Carlo Buontempo, Director of C3S, stated that the world is rapidly approaching the long-term temperature limit established by the 2015 Paris Agreement and is "bound to pass it," underscoring the necessity to manage the consequences of this overshoot. This persistent trend is further supported by the observation that the last eleven years constitute the eleven warmest years recorded since systematic observations began. Samantha Burgess, Strategic Lead for Climate at ECMWF, noted that while the natural influence of El Niño diminished in 2025, the underlying warming trend, driven by accumulated greenhouse gases, remains the dominant factor.

Analysis from the Copernicus Atmosphere Monitoring Service (CAMS), directed by Laurence Rouil, reinforces that sustained human activity resulting in steadily increasing greenhouse gas concentrations is the primary driver of these exceptional temperatures. The data also revealed severe regional extremes, including the Antarctic continent recording its warmest annual temperature ever, while the Arctic experienced its second warmest year. Concurrently, combined polar sea ice cover plummeted to its lowest level since satellite monitoring commenced in the 1970s, specifically during February.

Physical impacts were pronounced globally, with half of the world's land area enduring more days than average with 'strong' heat stress, defined as a 'feels-like' temperature of 32°C or higher. The World Health Organization recognizes heat stress as a leading cause of weather-related fatalities. These high temperatures contributed to the intensification of severe wildfires across North America and Europe in 2025, which degraded air quality through the emission of carbon and toxic particulate matter.

These scientific findings were released shortly after the UN Climate Summit, COP30, concluded in Belém, Brazil, in November 2025. Although nearly 100 nations updated their Nationally Determined Contributions (NDCs), the summit did not secure a binding roadmap for a fossil fuel phase-out, facing strong opposition from oil-producing states like Saudi Arabia. This policy stagnation contrasts with the scientific timeline, which suggests the 1.5°C long-term limit could be breached by the end of this decade, sooner than initially projected in the 2015 Paris Agreement. Research indicates that major Global North countries, including the United States, Canada, Australia, and Norway, have collectively increased oil and gas production by nearly 40% since the Paris Agreement was signed, directly impacting mitigation efforts.