UNEP says global temperatures are expected to exceed the Paris Agreement threshold within years, but rapid action could limit the overshoot.
PARIS, FRANCE — WEB DESK: The United Nations has warned that the world is likely to exceed the 1.5°C global warming threshold in the coming years, shifting the climate challenge from preventing an overshoot to limiting its scale and duration.
The warning came in a new report by the UN Environment Programme (UNEP), which examines how governments could respond if global temperatures temporarily rise above the target and how warming could eventually be brought back below it.
Scientists say warming beyond 1.5°C above pre-industrial levels increases the risks of extreme weather, ecosystem damage and other climate impacts.
1.5°C threshold expected to be exceeded
The 1.5°C target was established as the more ambitious goal of the 2015 Paris Agreement, under which nearly 200 countries agreed to pursue efforts to limit the rise in global average temperature to 1.5°C while keeping it well below 2°C.
However, UNEP said current policies and near-term emissions trajectories make an exceedance of 1.5°C widely assessed as unavoidable.
“The challenge has shifted from avoiding overshoot to navigating it,” the report said.
Richard Betts, a report co-author from the University of Exeter, described the assessment as a “reality check”, while stressing that countries still have significant scope to limit warming.
The report’s authors said policymakers need to adjust climate planning to account for an overshoot pathway.
Every fraction of warming matters
The UN stressed that crossing 1.5°C would not represent a single point at which all climate impacts suddenly become irreversible.
Instead, risks increase with every additional fraction of a degree and with the amount of time temperatures remain elevated.
UNEP warned that higher peak warming could increase the likelihood of severe heat, flooding, ecosystem losses and pressure on food and water supplies.
Scientists are also concerned about climate tipping points, including risks involving ice sheets, coral reefs and other vulnerable ecosystems.
The world has already warmed by roughly 1.4°C compared with the 1850–1900 period, according to the report cited by AFP.
UN says 1.5°C goal remains achievable
Despite the warning, the UN has not abandoned the 1.5°C objective.
UNEP Executive Director Inger Andersen said the target remains the goal, but countries now need to consider how to return to it after a period of overshoot.
UN Secretary-General Antonio Guterres has said temperatures could potentially be brought back below 1.5°C by the end of the century.
The UNEP assessment describes an “overshoot, peak and decline” pathway in which warming rises above the threshold, reaches a peak and subsequently declines.
The lower the peak and the shorter the period above 1.5°C, the lower the risks to people and ecosystems, according to UNEP.
Rapid emissions cuts remain critical
Returning global temperatures below 1.5°C would require much more than future reductions in greenhouse gas emissions.
The UNEP report says deep and rapid emissions cuts would need to be combined with carbon dioxide removal, which involves extracting carbon dioxide from the atmosphere and storing it.
Such measures could include nature-based approaches such as restoring forests, alongside other carbon-removal methods.
However, carbon removal remains controversial among climate campaigners, who warn that reliance on future technologies must not delay immediate reductions in coal, oil and gas use.
Lili Fuhr of the Center for International Environmental Law argued that cutting emissions now remains essential.
Climate campaigners express concern
The report’s language has prompted concern among climate activists who fear that acknowledging an inevitable overshoot could weaken political pressure to reduce fossil-fuel emissions.
Greenpeace International Deputy Programme Director Jasper Inventor described the development as deeply troubling but said an overshoot should not be treated as a reason to abandon the 1.5°C goal.
Climate scientist Bill Hare, chief executive of Climate Analytics, also criticised the report’s framing, warning that it could risk encouraging complacency.
The UN, however, says the assessment is intended to strengthen—not weaken—the case for urgent climate action.
As temperatures continue to rise, governments face the dual challenge of rapidly cutting emissions while preparing communities for increasingly severe climate impacts.
The central message from UNEP is that every fraction of warming matters, and reducing both the peak and duration of an eventual 1.5°C overshoot could significantly limit the damage caused by climate change.
