With global temperature rise set to exceed 1.5 degrees Celsius above pre-industrial levels, urgent and stringent cuts to greenhouse emissions are needed to minimise the magnitude and duration of overshoot and return to 1.5 degrees Celsius by the end of the century, according to a UNEP report.

The report has examined a “lowest possible” 1.5-degree Celsius overshoot scenario, in which peak warming by around the middle of the century is limited to 1.7-1.8 degrees Celsius, and global temperature rise is returned to or below 1.5 degrees Celsius by 2100, with about a 50% chance.

‘Emissions Gap Report 2026: The Point of Return’, released by the United Nations Environment Programme (UNEP) on Wednesday, revealed that to get onto this pathway, global greenhouse gas (GHG) emissions would have to be reduced by 18% by 2030, 45% by 2035, and 69% by 2040, all relative to 2025 levels.

In a statement, UN Secretary-General Antonio Guterres said, “Overshoot is not surrender. We can still keep it as small and as short as possible, and bring temperatures back below 1.5 degrees [Celsius] by the end of the century.”

The report also stated that if current policies continue, warming could reach 2.8 degrees Celsius within this century, and increase thereafter. If all Nationally Determined Contributions (NDCs) are delivered, and similar efforts continue, warming will be limited to 2.6 degrees Celsius.

Under the 2015 Paris Agreement, countries must finalise and submit NDCs every five years, with every successive NDC representing a progression over the existing one. The NDCs have to specify the set of actions a country is taking to fight climate change.

“New NDCs submitted since last year’s report have made a negligible difference for these projections. Even in the most optimistic scenario, where all NDCs plus additional net-zero targets are achieved, global warming would only be limited to 2.1 degrees Celsius in this century,” said the report.

It added that without urgent action, keeping peak warming below 1.7 to 1.8 degrees Celsius will quickly become impossible.

“Every additional fraction of a degree and additional year of warming above 1.5 degrees Celsius increases climate impacts and risks. So, we must pull out all the stops to minimise peak warming and return to 1.5 degrees Celsius by the end of the century. This is possible,” Inger Andersen, executive director of UNEP, said in a statement.