At a Glance

Scientists found record-warm water beneath the Thwaites Glacier.The warm water could speed up the collapse of the glacier.The demise of the Thwaites Glacier could raise sea levels more than 2 feet.

Scientists say the first recorded measurements of warm water under a glacier in Antarctica could signal the unstoppable demise of the Florida-sized ice sheet.

The warm water found below the Thwaites Glacier, part of the Western Antarctic Ice Sheet, was 3.6 degrees Fahrenheit above freezing, according to scientists from New York University and NYU Abu Dhabi.

The warm water was discovered at the glacier’s grounding zone, the point where the ice is no longer resting fully on bedrock but is floating on the ocean. As the ice at the bottom of the glacier melts, more of the glacier slides into the ocean. That causes sea level to rise.

"The fact that such warm water was just now recorded by our team along a section of Thwaites grounding zone, where we have known the glacier is melting, suggests that it may be undergoing an unstoppable retreat ," David Holland, director of NYU’s Environmental Fluid Dynamics Laboratory and NYU Abu Dhabi’s Center for Global Sea Level Change, said in a news release about the discovery.

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The Thwaites Glacier, which covers more than 74,000 square miles, is part of the West Antarctic Ice Shelf.

(NASA/OIB Jeremy Harbeck)

The collapse of the Thwaites Glacier, which covers more than 74,000 square miles, could , according to the International Thwaites Glacier Collaboration.

The melting of the glacier already accounts for about 4% of global sea level rise. Last year, an under the glacier.

Without the Thwaites acting as a brake, other parts of the West Antarctic Ice Sheet could slip into the sea faster and cause even more sea level rise — , according to Live Science.

This expedition was part of the . Five teams of scientists and engineers have been working on Thwaites for the last two months in below-freezing temperatures and extreme winds.

"We know that warmer ocean waters are eroding many of West Antarctica’s glaciers, but ," Keith Nicholls, an oceanographer from British Antarctic Survey and the U.K. lead on one of the teams, said in a statement. "This new data will provide a new perspective of the processes taking place so we can predict future change with more certainty."

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