AI data centers across the pond could emit nearly one million more tons of carbon dioxide into the atmosphere than previously estimated, according to newly inflated numbers released by the UK's governing body.

First spotted by Politico, UK officials quietly revised an initial range of estimates included in the country's "Compute Roadmap," a policy document outlining the UK's plan to scale its AI infrastructure and build a "world-class compute ecosystem." Previous versions of the document suggested the amount of energy used under current AI data center plans would result in a peak of 0.142 million metric tons (or 142,000 metric tons) of carbon emissions between 2025-2035.

But 2025's numbers, and the country's AI goals, appear to have altered that projection, with the document now listing the top value at 123 million metric tons. That's 100 times more than before, the Guardian reported, and is equivalent to the emissions typically generated by 2.7 million people.

Chi Onwurah, parliament member and chair of the body's science, innovation and technology committee, told Politico that the new numbers were concerning, demanding more transparency from UK leaders about the environmental impact of its AI plans. Multiple parliamentary groups are investigating AI's energy demands and fossil fuel consumption, as the country has pledged to reach net zero emissions by 2050.

Increased energy use by AI data centers in the U.S. have also led to a rise in global emissions, according to recent environmental reports. Domestically, U.S. greenhouse gas emissions went up for the first time in two years following a steady decline.

Concerns over the environmental impact of mass generative AI adoption aren't slowing down. Coalitions of environmental advocacy groups have called for federal moratoriums on data center builds. Communities nationwide have been fighting against local billion-dollar data center projects, even proposing state-level bans. Meanwhile, Big Tech's leaders and major AI investors have attempted to assuage climate concerns with promises to reduce and recycle water, use natural gas as an energy source, and offset energy costs.