UNEP Says 1.5°C Breach Is Now Unavoidable

The UN Environment Programme published its Emissions Gap Report 2026 on 21 October, and for the first time in the report's history it declares that missing the 1.5°C threshold is "imminent and unavoidable." The report, subtitled The Point of Return, does not treat that as the end of the target. It treats it as the start of a managed overshoot.

Current policies put the world on track for 2.8°C of warming this century, according to UNEP. Even if countries deliver their new climate pledges, the projected figure is 2.6°C. Both numbers sit far above the 1.5°C benchmark that has anchored a decade of climate diplomacy.

The report's central scenario is what it calls the "lowest possible" overshoot. Under it, peak warming around mid-century is limited to 1.7–1.8°C. Getting there requires emissions cuts of 18% by 2030, 45% by 2035 and 69% by 2040, all measured against 2025 levels, alongside increased CO2 removal through the century. That pathway returns temperatures to or below 1.5°C by 2100 — with roughly a 50% chance, not a guarantee.

UNEP's framing has shifted accordingly. Executive Director Inger Andersen said the 1.5°C window "has closed," but that it can be reopened by making the overshoot as brief as possible. UN Secretary-General António Guterres put it as "overshoot is not surrender," adding that temperatures can still be brought back below 1.5°C by the end of the century.

The report states that above 1.5°C, climate impacts and tipping-point risks intensify with every fraction of a degree, and describes an "overshoot, peak and decline" pathway as the best remaining option. That makes the size and duration of the overshoot — not just the long-term target — the operative measure of policy.

One data point complicates the picture without resolving it. Global carbon output appears to have stalled in 2025, with emissions broadly similar to the previous year. UNEP analysts were wary of calling it a peak or a plateau.

The report is timed to inform decision-makers ahead of COP31 in Turkey next month. The gap it identifies is not between targets and physics but between pledges and enacted policies — the 2.6°C and 2.8°C trajectories differ by what governments have actually done, not what they have promised.