Last year has been officially confirmed as the third-hottest on record, with climate experts stating that relentless human activity has pushed the world to the brink of breaching a critical global warming threshold. The findings lead scientists to declare the central goal of the 2015 Paris climate agreement – to keep global heating below 1.5C – effectively 'dead in the water'.
A Streak of Extraordinary Heat
According to a consolidated analysis by the World Meteorological Organization (WMO), 2025 continued a stark three-year streak of 'extraordinary global temperatures'. The data shows the average surface air temperature was 1.48C above pre-industrial levels. Separately, the EU's Copernicus Climate Change Service found the year was 1.44C hotter than the pre-industrial baseline.
Six of the eight major global datasets ranked 2025 as the third-hottest year since records began in the 19th century, with the remaining two ranking it second. The hottest year on record remains 2024.
The Inevitable Overshoot of 1.5C
Carlo Buontempo, Director of the Copernicus Climate Change Service, delivered a sobering assessment. 'We are bound to pass it,' he said, referring to the 1.5C Paris limit, which is measured over a 30-year average. 'The choice we now have is how to best manage the inevitable overshoot and its consequences.'
Current heating rates suggest this long-term average could be breached before 2030 – over a decade sooner than anticipated when the landmark Paris accord was signed. Bill McGuire, Emeritus Professor of Climate Hazards at University College London, echoed the dire outlook, stating: 'To all intents and purposes, the 1.5C limit is now dead in the water.'
Human Fingerprint on a Warming Planet
The primary driver of this unnatural heat is unequivocally the blanket of carbon pollution from burning fossil fuels. Laurence Rouil, Director of the Copernicus Atmosphere Monitoring Service, emphasised: 'The atmosphere is sending us a message. And we must listen.' The data for 2025 provides a clearer picture of underlying warming, as the temporary boost from the El Niño weather pattern weakened.
The consequences were felt across the globe. Antarctica endured its hottest year on record, while the Arctic saw its second-hottest. Polar sea ice cover hit its lowest February level since satellite observations began in the 1970s. Furthermore, half of the planet's land area experienced more days than average with at least 'strong' heat stress, where temperatures feel above 32C.
Despite a global boom in renewable energy, emissions have continued to rise in the decade since the Paris agreement. The analysis, based on billions of measurements from satellites, ships, and weather stations, paints a clear and urgent picture: dangerous climate breakdown has arrived, demanding an immediate and scaled-up response.
