UN Report Confirms Planetary Warming Will Breach 1.5 Degrees Celsius, Richer Nations Primarily to Blame

CAMBRIDGE, Mass. (November 4, 2025)-The United Nations Environment Programme (UNEP) released its annual Emissions Gap Report today. The analysis shows that without immediate, aggressive action the world is on track to endure a global average temperature rise of between 2.3 and 2.8 degrees Celsius above pre-industrial levels over this century. The U.S. withdrawal from the Paris Agreement, which goes into effect in January 2026, would add another 0.1 degrees Celsius to this range. This far exceeds the Paris Agreement temperature goals of keeping warming to well below 2 degrees Celsius and as close to 1.5 degrees Celsius as possible-a science-based goal recognized to significantly limit climate harms globally.

The report comes a week before the start of the U.N. annual climate talks (COP30) in Belém, Brazil, and raises alarms over the disconnect between insufficient pledges made by countries to reduce heat-trapping emissions, the lack of robust policies they have implemented to achieve those commitments and what the science shows is necessary to limit global average temperatures in line with the Paris Agreement goals. The stark conclusions related to the impending breach also highlight the critical need to simultaneously invest in robust adaptation measures.

Below is a statement by Dr. Rachel Cleetus, senior policy director for the Climate and Energy Program at the Union of Concerned Scientists (UCS). She has more than 20 years of experience working on international climate and energy issues, is a regular attendee of the annual U.N. climate talks and will be attending COP30.

"This report's findings, confirming that a crucial science-based benchmark for limiting dangerous climate change is about to be breached, are alarming, enraging and heart-breaking. Years of grossly insufficient action from richer nations and continued climate deception and obstruction by fossil fuel interests are directly responsible for bringing us here. World leaders still have the power to act decisively to sharply rein in heat-trapping emissions and any other choice would be an unconscionable dereliction of their responsibility to humanity.

"Costly and deadly climate impacts are already widespread and will worsen with every fraction of a degree, harming people's health and well-being, as well as the economy. Policymakers must seize the opportunity now to accelerate deployment of renewable energy and energy efficiency-solutions that are plentiful, clean and affordable-and transition away from polluting fossil fuels. Protecting people, livelihoods and ecosystems by helping them adapt to climate hazards is also critical as higher temperatures unleash rapidly worsening heat, floods, storms, wildfires, drought and sea level rise.

"Ambitious climate action can cut energy costs, improve public health and create a myriad of economic opportunities. Richer, high-emitting countries' continued failure to tackle the challenge head-on is undermining the well-being of their own people and is a monumental injustice toward lower-income countries that have contributed the least to this problem yet bear the most acute harms. It's past time for wealthy countries to heed the latest science and pay up for their role in fueling the climate crisis. With alarms blaring, the upcoming U.N. climate talks must be a turning point in global climate action. Powerful politicians and billionaires who willfully ignore urgent realities and continue to delay, distract or lie about climate change will have to answer to our children and grandchildren."

Additional UCS Resources:

• Blog post from Dr. Cleetus on priorities for COP30 and the danger of breaching 1.5 degrees Celsius of global warming
• Blog post from Dr. Carly Phillips on the science of overshooting climate goals
• Media advisory listing UCS experts attending COP30 in Brazil available for interviews
• All blog posts related to COP30
• Statement on President Trump's second withdrawal from the Paris Agreement