A new United Nations report warns that global temperatures are likely to exceed the 1.5°C threshold above pre-industrial levels within the next few years, marking a significant shift in the global climate outlook. The report, titled Limiting Overshoot and published on September 6, 2026, underscores that while the goal of keeping warming below 1.5°C set by the 2015 Paris Agreement remains vital, it is now considered virtually unattainable without temporary overshoot and subsequent cooling.
The analysis projects that global temperature rise could peak at approximately 1.8°C under optimistic assumptions or reach about 2.6°C if current policies remain unchanged. Presently, the planet has already warmed by about 1.4°C, with sporadic short-term spikes surpassing this level. The findings emphasize the importance of reversing warming by the end of the century through reducing greenhouse gas emissions combined with actively removing carbon dioxide from the atmosphere.
Debra Roberts, honorary professor at the University of KwaZulu-Natal and co-author of the report, described the situation as “a really critical point,” stating that the scale and speed of countries’ climate ambitions will determine whether overshoot persists briefly or endures for centuries. Achieving a decline in global temperature will require rapid reductions in fossil fuel pollution alongside large-scale carbon dioxide removal efforts, both through natural methods like reforestation and emerging technologies such as direct air capture.
The report highlights that merely stabilizing temperatures is insufficient, as some climate impacts—such as sea-level rise and biodiversity loss—may be irreversible. It stresses that every fraction of a degree increase in warming corresponds with heightened risks and more severe consequences. Recent extreme weather events underscore this reality: this summer alone, Europe experienced five deadly heat waves linked to tens of thousands of excess deaths, while wildfires have produced hazardous air quality across North America and Southeast Asia. Meanwhile, ongoing search efforts continue after a catastrophic glacial collapse in Nepal and China caused severe flooding, leaving thousands missing.
Looking ahead, the report cautions that rising sea levels threaten island nations with possible submersion, critical ocean currents could weaken, and health risks associated with climate change will escalate. Despite some progress, including a recent plateauing of emissions, the authors emphasize that emissions must be cut nearly in half by 2030 and approach net zero by mid-century to lessen the severity of warming.
The reliance on carbon dioxide removal technologies is expected to increase due to inevitable overshoot, though the report’s authors warn against treating such methods as a substitute for emission cuts. Richard Betts, a climate scientist at the University of Exeter and co-author, stressed the urgent necessity of reducing fossil fuel use alongside carbon removal efforts.
Adaptation to climate impacts is acknowledged as essential and interdependent with mitigation, as slowing emissions will help communities avoid increasingly frequent disasters while enabling more effective adaptation strategies.
The report calls on countries with the greatest historical emissions to lead mitigation efforts, with Inger Andersen, executive director of the UN Environment Programme, noting that the United States remains the largest cumulative emitter. It refrains from endorsing unproven geoengineering solutions such as atmospheric aerosol injection or ocean cloud brightening, citing a lack of sufficient scientific understanding.
Overall, the report marks a new phase in international climate policy, shifting the global focus from avoiding 1.5°C warming to managing inevitable overshoot and pursuing necessary measures to return temperatures to safer levels in the coming decades.