Global scientists have officially confirmed that 2025 was the third hottest year ever recorded, providing stark new evidence of an "unmistakable trend" towards a hotter world driven by human activity.
Data Reveals Sustained Temperature Rise
The findings, released by a consortium including the UK's Met Office, the University of East Anglia (UEA), and the National Centre for Atmospheric Science (NCAS), show a clear pattern of escalating heat. The data reveals that 2025 was the third consecutive year where global temperatures soared more than 1.4 degrees Celsius above pre-industrial levels.
According to the Hadcrut5 dataset compiled by the Met Office, UEA, and NCAS, last year's temperature was 1.41C above the 19th-century average. This places 2025 behind the record-breaking heat of 2024 and 2023. Meanwhile, the European Copernicus Era5 analysis presented an even higher figure, calculating the rise at 1.47C above pre-industrial benchmarks.
Human Activity is the Primary Driver
Experts were quick to underline the root cause of this sustained warming. Professor Tim Osborn, director of UEA's Climate Research Unit, explained that while the natural El Nino climate pattern added around 0.1C of extra heat in the preceding two years, its weakening in 2025 revealed the clearer picture of underlying, human-driven warming.
"The long-term increase in global annual average temperature is driven by the human-induced rise in the concentration of greenhouse gases in the atmosphere," stated Met Office climate scientist Colin Morice. He noted that year-to-year fluctuations stem from natural climate variations, but the overarching trend is unequivocally man-made, primarily through the burning of fossil fuels.
Approaching a Critical Threshold with Severe Consequences
The analyses place long-term temperatures between 1.37C and 1.4C above pre-industrial levels, meaning the world is perilously close to the 1.5C limit agreed by nations in the Paris climate accord. Breaching this threshold is expected to drastically worsen impacts like droughts, floods, extreme heat, wildfires, and ecosystem collapse.
Carlo Buontempo, director of the Copernicus Climate Change Service, emphasised the gravity of the situation: "The fact that the last 11 years were the warmest on record provides further evidence of the unmistakable trend towards a hotter climate." He warned that the world is rapidly approaching the Paris limit, and the focus must now shift to managing the inevitable overshoot and its consequences.
UK-based scientists echoed this urgent call to action. Professor Richard Allan from the University of Reading said the sustained warmth in 2025, without El Nino's influence, underscores the critical need to halt planetary heating by rapidly cutting greenhouse gases. Professor John Marsham of the University of Leeds painted a dire picture for future generations, warning of a climate shift comparable to the last ice age, but hotter, which would be catastrophic for ecosystems, human health, and food and water security.
Professor Marsham also highlighted a message from a recent National Emergency Briefing on Climate and Nature: acting on climate change can be profitable for the UK, even if other nations delay, by lowering costs with renewables, creating jobs, and boosting energy security. The consensus is clear: the data demands an urgent and decisive global response.
