Human-driven climate change has intensified wildfire seasons across the Americas making fires up to 30 times larger than they would have been in a pre-industrial climate, according to a major new international report. The State of Wildfires 2025 study, led by scientists from the UK Centre for Ecology & Hydrology (UKCEH), the UK Met Office, the University of Leicester, the University of East Anglia, and the European Centre for Medium-Range Weather Forecasts (ECMWF), paints a grim picture of how warming temperatures are fueling unprecedented fire activity.
Between March 2024 and February 2025, wildfires scorched 3.7 million square kilometres of land worldwide an area larger than India. Over 100 million people were affected, and global damages reached $215 billion. Fires released more than 8 billion tonnes of carbon dioxide, nearly 10% above the long-term average, largely driven by extreme burning in South America and Canada.
In Los Angeles, January 2025 wildfires were 25 times larger and twice as likely due to climate change, claiming 30 lives, displacing 150,000 people, and causing $140 billion in losses. Similarly, in South America Pantanal-Chiquitano region, fires were 35 times larger than those expected in a world without human-induced warming, with Bolivia and parts of Brazil recording their highest CO₂ emissions of the century.
Dr Zhongwei Liu from the University of Leicester National Centre for Earth Observation, who co-authored the report, said that satellite and climate model analyses clearly show how global warming has amplified extreme fire weather across all studied regions. Dr Douglas Kelley of UKCEH added that the evidence linking climate change to the frequency and severity of wildfires is now “unequivocal.”
In California, two and a half years of unusually wet weather led to dense vegetation growth, which later became fuel for fires when heatwaves struck. Similar conditions worsened fires across the Amazon and Congo, where extended dry seasons and degraded forests allowed flames to spread rapidly.
The report warns that without sharp reductions in global emissions, regions like the Pantanal-Chiquitano could face extreme fire seasons every 15 to 20 years by 2100 events once considered rare. In the Congo Basin, the frequency of such fires could rise five-fold, though strong climate action could limit the increase to about 11%.
Ahead of COP30, scientists are urging world leaders to commit to rapid emissions cuts this decade. Dr Liu stressed that where extreme fire risks can no longer be avoided, adaptation measures such as ecosystem restoration, better fire governance, and stronger community resilience will be critical to saving lives and ecosystems.
The report also calls for improved land and fire management strategies, including curbing deforestation, controlled burning to manage vegetation, wetland restoration, creating fire breaks near urban areas, and expanding early warning systems. Public awareness and prevention efforts are equally vital to stop accidental fires.
Researchers are now analysing recent wildfire activity in Southern Europe and the UK from the summer of 2025 to further understand the escalating global wildfire crisis and guide future mitigation strategies.