Today's global emissions are around 80 percent above the level that would have been needed by 2030 to hold warming to 1.5°C with little or no overshoot, according to the United Nations Environment Programme (UNEP). That arithmetic is why the title of this year's Emissions Gap Report, published on October 21, names not a goal but a place to come back from: "The Point of Return."

A goal that quietly changed

For years, the report measured national pledges against pathways that kept warming to 1.5°C with little or no overshoot. This year it drops them. The possibility of limiting warming to 1.5°C with limited or no overshoot "has now been lost," the authors write, as quoted by Carbon Brief, because those pathways assumed cuts starting in 2020 and emissions have kept rising.

What replaces them is a "lowest possible" overshoot scenario, in which warming peaks at 1.7 to 1.8°C around mid-century, with a 66 percent chance, and returns to 1.5°C or below by 2100, with about a 50 percent chance. UNEP calls a temporary breach of 1.5°C "imminent and unavoidable." The change also means this year's gap figures cannot be compared directly with earlier ones.

The temperature scoreboard

UNEP estimates that current policies lead to 2.8°C of warming by 2100, with a 66 percent chance, and a 10 percent chance of exceeding 3.4°C. Fully implementing unconditional pledges gives 2.7°C, all pledges 2.6°C, and pledges plus every net-zero target 2.1°C. Even the most optimistic case ends 0.25°C above the lowest-overshoot pathway, according to Carbon Brief's reading of the report.

The central estimates are 0.2 to 0.3°C higher than in last year's report. That is the surprise, because more countries have now put pledges on the table. By September 1, 124 parties had submitted third national climate plans covering 75 percent of global emissions, more than double the number available a year earlier.

Why it got worse as pledges got better

Two reasons stand out. The first is the formal withdrawal of the United States from the Paris Agreement. The second is that the report's authors harmonized their projections with updated historical emissions data. Together they raised projected 2035 emissions from the new pledges by about 3 gigatonnes of CO2 equivalent compared with last year's report.

Full implementation of all the new plans would cut 2035 emissions by only 3.5 gigatonnes compared with 2030 targets, and by 5 to 8 percent by 2030 and 11 to 15 percent by 2035 compared with 2025 levels. The 2030 implementation gap, the distance between what countries plan and what current policies deliver, has narrowed. But the report says this is because of the US exit, so the narrowing reflects "policy changes, not policy progress." Because the gap is about the same size in 2030 and 2035, it concludes that collective ambition in the 2035 pledges is weak.

The US also stands out on the numbers. Among the six largest emitters, only the US saw a notable increase in 2025, rising by 133 million tonnes, driven by higher electricity demand and a rebound in coal power, according to the report. Emissions in China, the EU, India, Russia and Indonesia were relatively flat.

What the lowest path demands

The arithmetic is unforgiving. Staying on the lowest 1.5°C overshoot pathway requires global greenhouse gas emissions to fall 18 percent by 2030, 45 percent by 2035 and 69 percent by 2040, relative to 2025, with net-zero CO2 around 2050. That means cutting 5.7 percent a year over the next decade, which the report notes is even faster than the 5 percent a year that would have been needed had cuts begun in 2019.

The path also leans on removing carbon dioxide from the air at scale to bring temperatures down after the peak. UNEP's summary, as reported by one outlet, puts the amount needed to return to 1.5°C at roughly 320 gigatonnes, comparable to about eight years of global CO2 emissions in 2024.

For energy, the benchmarks are blunt: coal use should fall about 15 percent by 2030 and 55 percent by 2035 relative to 2025. And the cost of delay is quantified: every five years of delay in cutting emissions locks in around another 0.1°C.

Where progress is real

The report is not pure gloom. Global emissions in 2025 were around 58.4 gigatonnes, comparable to 2024 and about 0.16 gigatonnes lower, though the authors say uncertainty is high and the direction cannot be confirmed. Emissions growth has slowed from 1.7 percent a year over 1990 to 2015 to 0.8 percent a year since 2016.

Renewables are the standout. The increase in renewable capacity has been three times higher than 2015 projections expected, and as a result energy-related CO2 emissions rose 40 percent less than forecast. Renewables are the only area the report finds on track for 2030. By contrast, fossil fuel supply continues to rise and efforts to halt deforestation are off track by more than a factor of 10.

What it means beyond the numbers

Temperature scenarios can feel abstract until they meet the places that are already responding. Carbon Brief noted that the ongoing "super" El Niño is likely to push land-use emissions up in 2026, and the same El Niño is why the Great Barrier Reef faces a calm-weather trap as it builds. And the 2°C-plus world these numbers describe is the one in which nearly half of reef-building corals already face elevated extinction risk.

The report lands just ahead of the COP31 climate conference in Türkiye next month. Its authors still see ample opportunity to accelerate, and their closing argument is conditional: countries can still limit peak warming and shorten the overshoot. The more useful number for negotiators may be the smallest one in the report. Each five-year delay costs about 0.1°C, so the real measure of a conference is whether it moves emissions this decade, not whether it restates a target for 2100.

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