Three of the world’s most iconic cities could be submerged if Antarctica’s so-called “Doomsday Glacier” collapses, and scientists say that scenario is growing increasingly likely. Climate change has long been associated with rising sea levels, warmer temperatures, and more frequent extreme weather events.
But new research on the Thwaites Glacier, ominously nicknamed the “Doomsday Glacier,” is putting the potential consequences into sharper and more alarming focus, according to BBC Science Focus. Situated in West Antarctica, Thwaites Glacier holds enough frozen water to raise global sea levels by more than two feet on its own.
Scientists warn, however, that a full collapse could set off a chain reaction destabilizing the far larger Antarctic ice sheet. That worst-case outcome could push sea levels up by as much as 10 feet, enough to inundate major cities including London, New York, and Bangkok.
These densely populated urban centers would be among the first to experience catastrophic and potentially irreversible flooding. Researchers have been tracking the glacier’s behavior through the International Thwaites Glacier Collaboration, a scientific initiative that launched in 2018 specifically to assess the glacier’s stability.
Their findings have raised serious concern: a network of so-called hidden lakes lurking beneath the glacier’s surface appears to be playing a far larger role in accelerating its potential collapse than previously understood. A study published in March 2025, led by Professor Noel Gourmelen of the ITGC, confirmed that drainage from these subglacial lakes is significantly speeding up ice loss.
“We expected that water draining from the underside of the ice sheet plays a role in modulating ocean melting,” Gourmelen said. “The sheer magnitude of this lake drainage gave us the opportunity to finally observe and quantify its impact.
The lake outflow took place in a key sector impacting Thwaites’ stability. The drainage in effect momentarily turbo-charged Thwaites’ ocean-driven retreat.”
This alarming acceleration comes against a backdrop of higher-than-expected temperatures across the Southern Hemisphere in 2025, raising fears that the glacier could be melting faster than models had projected. Dr.
Alastair Graham, a marine geologist at the University of South Florida and a fellow ITGC member, put the stakes plainly. “If Thwaites Glacier collapses, it would cause a rise of around 65cm in sea level,” he told News.
“This year is really different. It’s very difficult to recover from this in one season.
The game has changed.” Although a full collapse of the glacier may still lie decades or even centuries ahead, the latest data suggests that a critical tipping point could arrive far sooner than researchers had hoped.
Should that threshold be crossed, the consequences for the world’s coastlines, economies, and hundreds of millions of people could prove impossible to reverse.