UN report: Trump’s withdrawal from Paris contributed to a worsened global warming outlook

The United Nations’ latest emissions gap assessment warns that the world is now on course to breach 1.5 °C of warming and that the consequences of the United States' withdrawal from the Paris Agreement under President Donald Trump have worsened the outlook. The UN report, issued on 21 October 2026, finds that decades of insufficient cuts to fossil-fuel emissions leave the 1.5 °C threshold "imminent and unavoidable."

If current climate policies remain in place, the UN projects average warming this century of 2.8 °C above pre‑industrial levels; even if countries meet their recent new pledges, warming would still reach about 2.6 °C. Those trajectories, the report says, would push the planet into an era of far more frequent and severe extremes.

How policies and emissions trends widened the gap

The assessment quantifies the gap between promises and action. A total of 167 countries have submitted climate action plans that cover 83 percent of global greenhouse-gas emissions, but the measures pledged fall far short of what is needed. Preliminary estimates show emissions rose in 2025 in several large emitters — Indonesia, China and the United States — with the rise in the U.S. "far outpacing that in all other countries," driven in part by a renewed increase in coal use and higher electricity demand linked to a rapid expansion of artificial‑intelligence data centres.

The outlook deteriorated after the U.S. withdrawal from the Paris Agreement and, following Donald Trump’s return to the White House, his administration substantially rolled back climate rules and expanded oil and gas production. "The main message is simple: governments must start implementing policies that reduce the use of fossil fuels as quickly as possible," said Bill Hare, executive director of the global science and policy institute Climate Analytics.

The report underlines stark impacts if 1.5 °C is exceeded even temporarily: loss of coral reefs, long‑term retreat of ice sheets and the possible conversion of the Amazon from forest to savannah. This year alone Europe registered more than 32,000 excess heat‑related deaths, and nearly 1,500 people died in flash floods in Nepal and Tibet after conditions created by climate change triggered a glacier collapse.

To limit the peak of warming and return to 1.5 °C by 2100 under an optimistic scenario, the UN outlines that global emissions would need to fall by about 69 percent by 2040 relative to 2025 and that roughly 330 billion metric tons of CO2 would have to be removed and stored underground. The report also cautions about the costs and scalability of large‑scale carbon removal. "Exceeding does not mean surrender," said UN Secretary‑General Antonio Guterres. "We can still make the overshoot as small and as short as possible and bring temperatures back below 1.5 °C before the end of the century."

At the same time, the UN highlights that climate policies can work: carbon‑pricing pilots in China have reduced emissions by about 11 percent, and the EU emissions‑trading system has achieved an 8 percent reduction compared with projected levels without the policy. Renewable capacity has expanded far faster than expected since the Paris Agreement: global renewable electricity capacity grew roughly three times faster than anticipated, solar deployment proceeded seven times faster, and in 2024 more than 90 percent of renewable projects were cheaper than fossil alternatives. "We must use every available means to limit the peak of warming and by the end of the century bring temperatures back to 1.5 degrees," said Inger Andersen, executive director of the UN Environment Programme. "That is possible."

Photo: press material from the event