Earth logs third-warmest year in 2025 as 1.5°C threshold breached for three years, scientists confirm

In 2025, Earth experienced its third-warmest year on record with average temperatures exceeding 1.5 degrees Celsius of global warming over three years, marking the longest period since records began, EU scientists confirmed on Wednesday, news agency Reuters reported.

Data from the EU’s European Centre for Medium-Range Weather Forecasts showed that the past three years were the hottest on record, with 2025 only 0.01 degrees Celsius cooler than 2023. The UK Met Office, Britain's national weather service, also confirmed 2025 as the third-warmest in since 1850 when records began. These temperature figures are likely to be published by the World Meteorological Organisation on Wednesday.

The ECMWF said the planet has also recorded its first three-year stretch in which average global temperatures were 1.5 degrees Celsius above pre-industrial levels, a threshold scientists warn could trigger severe, and in some cases irreversible, consequences of global warming.

"1.5 C is not a cliff edge. However, we know that every fraction of a degree matters, particularly for worsening extreme weather events," said Samantha Burgess, strategic lead for climate at ECMWF.

Commitment to limiting global temperature rise to 1.5 degrees Celsius

Under the 2015 Paris Agreement, governments committed to limiting global temperature rise to 1.5 degrees Celsius above pre-industrial levels, measured over several decades. However, ECMWF stated that inadequate cuts in greenhouse gas emissions mean the world could cross this limit before 2030 — around a decade earlier than expected when the accord was signed.

"We are bound to pass it," said Carlo Buontempo, director of the EU's Copernicus Climate Change Service. "The choice we now have is how to best manage the inevitable overshoot and its consequences on societies and natural systems."

At present, the world's long-term warming level is about 1.4 °C more than the pre-industrial era, according to ECMWF. On a short-term basis, the 1.5-degree threshold was already surpassed in 2024. Even a temporary breach of the long-term 1.5 °C limit would result in more intense and widespread impacts, such as longer and hotter heatwaves, along with stronger storms and flooding.

Meanwhile, wildfires in Europe generated the highest total emissions on record in 2025. However, scientific studies indicated that specific weather events were made worse by climate change, which include Hurricane Melissa in the Caribbean and monsoon rains in Pakistan, claiming the lives of over 1,000 people in floods.