UN Emissions Gap Report Says Overshoot Is Now Unavoidable

The world has run out of road on the Paris Agreement's most famous target. The United Nations Environment Programme said in the UN emissions gap report, released October 21 in Nairobi, that holding warming to one-point-five degrees above pre-industrial levels with no or limited overshoot is no longer possible. The chance to stay under the threshold without crossing it has closed, according to the report, and the task now is to keep the overshoot as small and as brief as possible, then bring temperatures back down by the end of the century.

The path back is steep

The report sketches a lowest possible overshoot path. On that path, warming peaks between 1.7 and 1.8 degrees around the middle of the century, then returns to one-point-five degrees or below by the end of the century, with about even odds. Getting there means cutting global greenhouse gas emissions by 18 percent by 2030, by 45 percent by 2035, and by 69 percent by 2040, all measured against 2025 levels. That pace works out to roughly six percent a year, every year, until the middle of the next decade.

Current national pledges do not come close. Even if every country delivered its climate plan in full, emissions would fall only a small single-digit share by the end of the decade, and only slightly more five years after that, according to the report. Under policies already in place, the planet is on course for about 2.8 degrees of warming this century. Full delivery of existing pledges would still leave warming near 2.6 degrees, while a midcentury net-zero path would still approach roughly 2.1 degrees.

The American exception

The United States stands out as the exception. American greenhouse gas emissions rose by about 133 million metric tons of carbon dioxide equivalent last year, an increase of roughly 2.4 percent that far exceeded any other country's, according to reporting on the report by AFP. The country was the only major economy where planet-warming pollution climbed sharply, leaving it tied with Russia for the highest per-person emissions among the largest economies. The report ties the rise to growing electricity demand, a rebound in coal power after gas prices rose, and greater power use from data centers. It also points to policies that kept coal plants open longer, rolled back vehicle fuel-efficiency standards, and ended tax credits for solar and wind projects.

Global emissions, meanwhile, were roughly flat last year at 58.4 billion metric tons of carbon dioxide equivalent, close to the previous record. Fossil fuels still dominate energy supply even as renewable power grows fast and clean energy costs fall, the report notes.

Returning temperatures to the threshold after an overshoot would require removing about 320 gigatonnes of carbon dioxide over the course of the century, a scale the report describes as costly, uncertain, and carrying major risks. Every five years of emissions at current rates adds about a tenth of a degree to peak warming. The report calls for tripling renewable electricity capacity within a decade and phasing out coal over the same stretch, according to the release. It also credits climate policies already in place with real reductions, noting that evaluated electricity policies cut emissions by an average of nine percent and that carbon pricing tools delivered smaller but measurable cuts across sectors.

The findings land weeks before the COP31 climate summit in Antalya, where governments open the second Global Stocktake of progress under the Paris Agreement. Pacific island advocates, reacting to the UN emissions gap report, warned that every fraction of a degree above the threshold carries consequences for islands, oceans, and people, and that overshoot must not become permission to delay action. Related coverage has tracked deadly summer heat across Europe and a fierce autumn storm in Scotland.

United Nations Secretary-General António Guterres framed the message in blunter terms, saying overshoot is not surrender and urging cuts that keep the overshoot small and short. The world has already warmed by roughly 1.4 degrees, and crossing the threshold is expected within years, according to the report. The American government disputes the report's conclusions, has quit the Paris Agreement, and will skip the November talks, according to a statement from the administration included in the report.