UN report finds 1.5°C warming overshoot unavoidable without much faster emissions cuts

The world is no longer on a credible path to avoid exceeding 1.5°C of global warming, according to the UN Environment Programme’s 2026 Emissions Gap Report. But the report also finds that the eventual temperature rise is not fixed: faster emissions reductions could keep the overshoot smaller and, in its most ambitious scenario, bring global temperatures back to around 1.5°C by the end of the century.

The figures describe warming compared with the pre-industrial period, before large-scale fossil-fuel use. If governments fully carry out their current national climate pledges, global temperatures are projected to reach about 2.6°C above that baseline by 2100. Under policies already in force, rather than promises that have not yet been implemented, the estimate is closer to 2.8°C.

These projections are not forecasts of a single unavoidable future. They compare the emissions implied by national plans and policies with pathways that would sharply reduce greenhouse-gas pollution. The plans submitted by 167 countries cover roughly 83% of global emissions, according to an account of the report by Deutsche Welle, but the ambition and implementation of those plans remain well short of what is needed.

The report’s most favorable pathway would still involve a temporary rise above 1.5°C. Warming would peak at approximately 1.7–1.8°C around the middle of the century before declining to 1.5°C or slightly below by 2100. Even this outcome is estimated to have only about a 50% probability, and it depends on substantial removal of carbon dioxide from the atmosphere.

Reaching that pathway would require global greenhouse-gas emissions to fall 18% below 2025 levels by 2030, 45% by 2035 and 69% by 2040. Current pledges provide much smaller reductions. The scale of these milestones means that the question is no longer only whether the world can prevent an initial breach of 1.5°C, but also how high temperatures rise, how long they remain elevated and whether a later decline is possible.

A warmer world affects every region, although the risks are unevenly distributed. Higher average temperatures increase pressure on food and water systems, human health, ecosystems and infrastructure. Temporary overshoot also matters because some consequences, including damage to ice sheets, coral reefs and other climate-sensitive systems, may not be easily reversed when global temperatures eventually fall.

The report does identify evidence that policy can change emissions trends. Renewable power is expanding, and measures such as carbon markets have produced measurable reductions in some places. Deutsche Welle reports estimates that pilot carbon markets in China cut emissions by about 11% compared with a projected alternative, while the European Union’s emissions-trading system reduced emissions by an estimated 8% against its expected level. These examples do not close the global gap, but they show that climate policy can deliver results when it is designed and enforced.

Recent emissions trends remain troubling. The Associated Press, drawing on the UN assessment, reports that United States emissions rose by about 133 million tonnes of carbon-dioxide equivalent in 2025, representing around 70% of the increase among countries whose emissions grew that year. Deutsche Welle also describes increases in emissions from the United States, China and Indonesia; in the United States, coal-fired electricity generation and rising demand for power contributed to the increase.

Carbon removal is central to the report’s most optimistic pathway because emissions cuts alone may not bring temperatures down quickly enough after an overshoot. Removing hundreds of billions of tonnes of carbon dioxide would be technically difficult, expensive and uncertain at the required scale. Nature-based approaches can face limits involving land, permanence and competing uses, while engineered methods remain costly and are not yet widely deployed.

The report’s central message is therefore both a warning and a constraint on expectations. Existing pledges point toward substantially more warming than the Paris Agreement’s temperature goals, while the 1.5°C threshold without overshoot is no longer considered attainable. Yet rapid action can still reduce the peak, limit long-term harm and preserve a possible route toward lower temperatures later this century.