The Earth could be doomed to breach the symbolic 1.5C warming limit in as little as three years at current levels of carbon dioxide emissions.
That’s the stark warning from more than 60 of the world’s leading climate scientists in the most up-to-date assessment of the state of global warming.
Nearly 200 countries agreed to try to limit global temperature rises to 1.5C above levels of the late 1800s in a landmark agreement in 2015, with the aim of avoiding some of the worst impacts of climate change.
But countries have continued to burn record amounts of coal, oil and gas and chop down carbon-rich forests – leaving that international goal in peril.
Climate change has already worsened many weather extremes – such as the UK’s 40C heat in July 2022 – and has rapidly raised global sea levels, threatening coastal communities.
“Things are all moving in the wrong direction,” said lead author Prof Piers Forster, director of the Priestley Centre for Climate Futures at the University of Leeds.
“We’re seeing some unprecedented changes and we’re also seeing the heating of the Earth and sea-level rise accelerating as well.”
These changes “have been predicted for some time and we can directly place them back to the very high level of emissions”, he added.
At the beginning of 2020, scientists estimated that humanity could only emit 500 billion more tonnes of carbon dioxide (CO2) – the most important planet-warming gas – for a 50% chance of keeping warming to 1.5C.
But by the start of 2025 this so-called “carbon budget” had shrunk to 130 billion tonnes, according to the new study.
That reduction is largely due to continued record emissions of CO2 and other planet-warming greenhouse gases like methane, but also improvements in the scientific estimates.
If global CO2 emissions stay at their current highs of about 40 billion tonnes a year, 130 billion tonnes gives the world roughly three years until that carbon budget is exhausted.
This could commit the world to breaching the target set by the Paris agreement, the researchers say, though the planet would probably not pass 1.5C of human-caused warming until a few years later.
Graph showing rise in global air temperatures since 1850. Temperatures have risen particularly quickly since the 1970s. There are two lines in different shades of red, one showing yearly averages and one showing 10-year averages. In 2024, temperatures were more than 1.5C above pre-industrial levels of the late 1800s. The 10-year average from 2015-2024 was 1.24C above pre-industrial.
Last year was the first on record when global average air temperatures were more than 1.5C above those of the late 1800s.