With global temperatures set to rise more than 2.7 degrees Fahrenheit (1.5 degrees Celsius) above pre-industrial levels within the next few years, nations urgently need to cut carbon emissions to avoid the worst impacts of climate change. A new report shows that America’s retreat from climate action is seriously undermining those efforts.
Scientists with the United Nations Environment Programme (UNEP) found that U.S. carbon emissions rose by 133 megatons last year, far exceeding all other major economies. The increase was driven by surging electricity demand and a rebound of coal power generation, according to the report. The U.S. also tied with Russia for the highest per capita carbon emissions at nearly 18 tons.
Trump administration policies helped drive that increase and have significantly worsened U.S. emissions projections, the report states. By 2030, emissions are now expected to be nearly 0.9 gigatons higher than projections based on policies under the Biden administration.
The consequences of America’s climate inaction will be felt around the world. The report quantifies how U.S. emissions are disproportionately worsening this crisis, and with every fraction of a degree temperatures rise, so do the risks.
The 3 Rs: Retreat, Repeal, Rollback
Over the past year, the Trump administration has worked to dismantle U.S. climate policy and clean energy growth while rapidly expanding domestic oil and gas production. Most climate policies from the Inflation Reduction Act were repealed under the One Big Beautiful Bill Act, and sweeping deregulation has rolled back power plant and vehicle emission standards, federal support for electric vehicles, methane emissions regulation, and renewable energy expansion.
One of Trump’s first actions as president was formally withdrawing the U.S. from the Paris Agreement—for the second time. When it was adopted, this international treaty aimed to limit global warming to 2.7 degrees F (1.5 degrees C). That goal is now effectively unachievable.
The new UNEP report lays out the emissions cuts needed to limit overshoot as much as possible, aiming to keep peak warming around mid-century below 3.1 to 3.2 degrees F (1.7 to 1.8 degrees C). Global emissions cuts of 18% by 2030 and 45% by 2035 will be necessary for this best-case scenario, on top of increasing CO2 removal over the course of the century.
Even if all parties to the Paris Agreement delivered on their current emissions reduction goals and then continued their efforts, the world wouldn’t come close to achieving those cuts, according to the report. In that scenario, there’s a 66% chance of limiting warming to 4.7 degrees F (2.6 degrees C) by 2100.
“This is a worse outcome than expected last year, as a result of the formal withdrawal of the United States of America from the Paris Agreement and revised estimates of historical emissions,” the report states. Compared to last year’s report, projected warming has increased 0.4 to 0.5 degrees F (0.2 to 0.3 degrees C), and about half of the higher warming estimate is due to America’s abandonment of its emissions reduction goals.
The report comes just weeks before nations convene in Türkiye for COP 31, the 31st Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC). These annual negotiations aim to reach consensus on policies that limit planet-warming emissions, and this year, the inevitability of overshoot will bring a renewed sense of urgency.
Despite its outsized role in driving the climate crisis, it’s not likely that the U.S. will attend.
