UN acknowledges for the first time that limiting warming to 1.5°C is effectively impossible

The United Nations has acknowledged in an official report that the world is likely to breach the 1.5°C warming target, a goal it had continued to present as achievable. The new report says the threshold will probably be exceeded within the next several years.

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Unfortunately, we will see more events like the devastating floods in Nepal, and that is why we need to control the peak of global warming.

The UN Environment Programme’s report, titled “Limiting Overshoot,” projects that warming could peak at 1.8°C around the middle of the century under the most optimistic scenario. If countries maintain their current policies, the peak could reach 2.6°C.

Nearly 200 countries agreed in the 2015 Paris climate accord to limit warming because of the risks associated with temperatures rising more than 1.5°C above preindustrial levels. Global temperatures have already risen by about 1.4°C compared with 1850 to 1900. Although the annual average exceeded 1.5°C in 2024, the target uses a longer-term average of about two decades, so scientists do not yet consider the threshold permanently breached.

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1.5°C is still our goal, but now we need to approach it from above in a different way than before.

The report proposes shifting the goal toward reversing climate change after the 1.5°C threshold is crossed, with efforts aimed at returning warming below it before the end of the century. It warns that the decades spent above the threshold will bring more severe climate events and cause more people to die, suffer injuries and become ill.

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This is the bleakest of the UN climate reports so far. The report contains despair, frustration and urgency, but it is not resigned. Even lowering warming by 0.1°C would reduce the damage by that amount.

Richard Betts, a report co-author and climate scientist at Britain’s Met Office and the University of Exeter, said, “Unfortunately, we will see more events like the devastating floods in Nepal, and that is why we need to control the peak of global warming.” UNEP Executive Director Inger Andersen said 1.5°C remained the goal, but countries should now approach it from above. Andrew Weaver of the University of Victoria called the report the UN’s “most bleak” climate report, while stressing that every tenth of a degree avoided would reduce harm. The report says countries must move beyond offsetting emissions and achieve net-negative emissions, combining rapid cuts with carbon removal. Experts warned that carbon removal cannot replace reductions in fossil-fuel use.

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We cannot rely on carbon-removal technology as an absolution. We need to cut emissions much more urgently than before.