New Delhi, June 20: The world could exhaust its remaining carbon budget to limit global warming to 1.5 degrees Celsius in just over three years if carbon dioxide emissions continue at current levels, according to a new international study published in Earth System Science Data.
The carbon budget represents the total amount of CO₂ humanity can emit while still maintaining a likely chance of staying below a specific global temperature threshold—1.5°C, as agreed under the 2015 Paris Agreement.
Exceeding this budget doesn’t result in an immediate breach of the 1.5°C limit, but puts the planet on an accelerated path to surpass it unless emissions are rapidly reduced.
The study, part of the “Indicators of Global Climate Change” report, also found that the carbon budget for keeping warming under 2°C could be depleted by 2048 if current emission trends persist.
Researchers estimate that 53 billion tonnes of CO₂ equivalent are being released each year, driven primarily by fossil fuel combustion and deforestation. From 2015 to 2024, the Earth has warmed by 1.24°C above pre-industrial levels, with 1.22°C of that warming attributed to human activity.
2024 was officially the hottest year on record, becoming the first calendar year with a global average temperature exceeding 1.5°C above the 1850–1900 baseline—used to measure pre-industrial temperatures. However, a permanent breach of the Paris target refers to sustained warming over two to three decades.
In May, the World Meteorological Organization (WMO) projected a 70% chance that global temperatures between 2025 and 2029 will temporarily exceed the 1.5°C threshold.
The UN Intergovernmental Panel on Climate Change (IPCC) had earlier stated that to stay within the 1.5°C limit, the world must cut greenhouse gas emissions by 43% by 2030, compared to 2019 levels. But IPCC Chair Jim Skea warned in March this year that the target is now outdated due to delayed action, and much deeper cuts are now required.