Deliver every national climate pledge in full and on time, and warming is still projected at 2.3–2.5°C.
Success is not the same as enough
The familiar climate story is that countries are falling behind their promises. They are: on current policies, UNEP projects about 2.8°C of warming this century.
So run the other scenario. Assume every country delivers its national pledge — its NDC — in full, on schedule. UNEP's 2025 Emissions Gap Report projects that world at 2.3–2.5°C this century — still past the "well below 2°C" the Paris Agreement commits to, and nowhere near 1.5°C.
Add every country's longer-term net-zero target as well, and UNEP's most optimistic scenario comes in around 1.9°C — below 2°C, but still well above 1.5°C.
That is the part worth sitting with. The gap is not only between what countries promised and what they will do. It is inside the national pledges themselves.
The problem isn't only that countries miss their targets. It's that hitting them wouldn't be enough.
Most of this year's improvement is bookkeeping
Both numbers did fall from the previous report, where full delivery gave 2.6–2.8°C and current policies 3.1°C. That looks like a year of progress.
Read the footnotes. About 0.1°C of the improvement comes from a change in methodology rather than anything happening in the atmosphere. Another 0.1°C will be cancelled by the United States withdrawing from the Paris Agreement. UNEP's own assessment is that the new pledges barely moved the needle.
What is genuinely working is real: solar and wind set deployment records in 2024 and 2025 and are now the cheapest new power in most markets. Electric car sales passed 20 million in 2025, up 20% — a quarter of all new cars sold. Amazon deforestation measurably declined under Brazil's policy changes. These are not nothing — they are just not yet fast enough to offset fossil fuel expansion elsewhere.
What that range actually looks like
Past 2°C the damage curves sharply at every decimal. Crop yields fall in tropical regions. Sea levels keep rising through 2100, forcing coastal cities to retreat. Ice sheet collapse, Amazon dieback and permafrost thaw stop being low-probability scenarios and become risks that activate across the range.
The floods and heatwaves making headlines today become the baseline, not the exception.
The debate has quietly shifted. It is no longer whether the world overshoots 1.5°C, but by how much — and whether anyone raises their pledges before the arithmetic hardens.
Sources checked 25 September 2026·4 sources ↓