The report states that the best chance of restoring a safe climate is to begin cutting greenhouse gas emissions immediately, halve them by 2035, and remove billions of tons of carbon dioxide from the atmosphere before the end of the century. Every five years of delay in reducing emissions adds at least a tenth of a degree to peak warming.

Scientists have calculated that at the current pace of emissions, warming could reach 2.7 to 3 degrees Celsius by 2100. If all measures promised by governments under the Paris Agreement are implemented, warming could be limited to about 1.7 or 1.8 degrees Celsius.

"We must make the overshoot as small and short as possible, limiting how high temperatures rise and how long they remain above 1.5 degrees Celsius," United Nations Secretary-General António Guterres said. He added that humanity is speeding past the limit to avoid climate catastrophe.

The report identifies accelerating the phaseout of fossil fuels, slashing methane pollution, and protecting lands, forests, and oceans as key climate actions. Planting trees could, at most, shave a tenth of a degree off global temperatures, according to the report.

"We’ve failed to act on the options that were available 15 or 20 years ago to reduce emissions rapidly," said Joeri Rogelj, a climate scientist at the International Institute for Applied Systems Analysis in Austria and a professor at Imperial College London. He stated that the reality is that we have failed in that endeavor, and it needs to be acknowledged.

Rogelj noted that if we act now we can limit overshoot. Not a safe world, but safer than remaining above 1.5 degrees for the long term. The report describes the goal of net zero emissions as an essential milestone that cannot be skipped.

Andersen stated that let’s be very clear, 1.5 target is still the goal. But now we need to approach it differently from above. The average global temperature could be returned to 1.5 degrees Celsius this century only if heating stayed below about 1.8 degrees Celsius.

"It's a reality check. We have to live with this warmer world. But there's still a lot we can do to limit warming," said Richard Betts, a climate scientist at the University of Exeter and UK Met Office. He noted that specific events are complicated but committed glacier loss can be stopped from getting much worse by reducing emissions and limiting the amount of warming.

The report concludes that if Earth stays in the overshoot zone too long, it could push ice sheets and key heat-carrying ocean currents past tipping points that become difficult or impossible to reverse on human timescales. Heating of up to 3 degrees Celsius above preindustrial levels could lead to glaciers losing more than a quarter of their mass by 2100, raising sea levels by up to 13 centimeters.

Global food production could decline by up to 14% by 2050 if there are not effective strategies to adapt. Extreme heat contributed to about 15,000 heat-related deaths in Germany this summer.

"We are seeing what it entails to adapt to climate change, and we are seeing that we have an enormous gap," said Carl-Friedrich Schleussner, a climate researcher at the International Institute for Applied Systems Analysis. He added that we are really lagging behind and are not prepared for what is coming.

Bill Hare, chief executive of Climate Analytics, said the UNEP report did a poor job of showing that there is a way out of the climate crisis. Andrew Weaver is a climate scientist at the University of Victoria.

Surangel Whipps Jr, President of Palau, expressed the sentiment of frontline communities. He said it is hard to overstate the depth of emotion for those of us living on the frontline after having fought so hard to put the 1.5C limit at the heart of the Paris agreement.

Whipps Jr stated that we need to see an urgent and unprecedented increase in political will and investment in a climate safe future. Nobody can read this report and conclude otherwise. Vishal Prasad, representative of Pacific Island Students Fighting Climate Change, cited legal obligations.

Prasad said the International Court of Justice has made it clear that keeping to 1.5C is not a choice, it is a legal obligation. He added that they are not asking for goodwill or begging, but telling governments what international law requires, including ending fossil fuel expansion so corporate profits do not extinguish their future.

Why It Matters

The 1.5 degrees Celsius warming threshold refers to the increase in global temperatures since the preindustrial period of 1850 to 1900. More than 190 countries pledged under the 2015 Paris Agreement to keep global temperature increases below 1.5 degrees Celsius. The report published on September 2, 2026, confirms that this threshold will be exceeded within the next few years.

The consequences of exceeding these limits include irreversible changes to ocean currents and ice sheets. The scale of required adaptation is showed by recent heat-related deaths and potential declines in food production. The report emphasizes that immediate action to halve emissions by 2035 remains the best path to mitigate long-term risks.

What's New

"We have to act with urgency and determination. Every fraction of a degree avoided, every year by which overshoot is shortened, and every adaptation action taken will save lives, will protect ecosystems, and reduce economic losses." "Let’s be very clear, 1.5 target is still the goal. But now we need to approach it differently from above." "If we act now we can limit overshoot. Not a safe world, but safer than remaining above 1.5 degrees for the long term."

"It is hard to overstate the depth of emotion for those of us living on the frontline after having fought so hard to put the 1.5C limit at the heart of the Paris agreement." "The International Court of Justice has made it clear – keeping to 1.5C is not a choice, it is a legal obligation."

How Sources Differ

António Guterres stated: "We must make the overshoot as small and short as possible, limiting how high temperatures rise and how long they remain above 1.5 degrees Celsius." The United Nations Environment Programme report Limiting Overshoot stated: Heating of up to 3 degrees Celsius above preindustrial levels could lead to glaciers losing more than a quarter of their mass by 2100, raising sea levels by up to 13 centimeters.

The United Nations Environment Programme report Limiting Overshoot stated: Existing national policies are projected to lead to at least 2.3 degrees Celsius heating, but it would still be possible to limit warming to below 2 degrees Celsius if countries delivered on net zero emissions commitments by mid-century.

The United Nations Environment Programme report he stated: Governments' current policies are projected to push temperatures to 2.6 degrees Celsius above pre-industrial levels by 2100.

The United Nations Environment Programme report he stated: The world is now at 1.4 degrees Celsius above pre-industrial levels, based on a 20-year average.

The United Nations Environment Programme report he stated: Global heating will reach at least 1.8 degrees Celsius under even the most optimistic future scenario, according to the UN report. The Paris Agreement stated: More than 190 countries pledged under the 2015 Paris Agreement to keep global temperature increases below 1.5 degrees Celsius.

The United Nations Environment Programme report he stated: The average global temperature could be returned to 1.5 degrees Celsius this century only if heating stayed below about 1.8 degrees Celsius.

The United Nations Environment Programme report he stated: Existing national policies are projected to lead to at least 2.3 degrees Celsius heating, but it would still be possible to limit warming to below 2 degrees Celsius if countries delivered on net zero emissions commitments by mid-century.