Skip to main content

Sign up for our newsletter.

Quality journalism. Progressive values. Direct to your inbox.

The Thwaites Glacier in Antarctica has been called one of the world's most "dangerous" glaciers because of the significant sea level rise its melting would cause. (Photo: Stuart Rankin/Flickr/cc)

City-Sized 1,000-Foot Deep Cavity Found in Glacier, Warns NASA, Signaling 'Rapid Decay' of Antarctic Ice

If the Thwaites Glacier were to eventually collapse into the ocean, scientists fear, "it might be more than a scientific curiosity. Indeed, it might be the kind of event that changes the course of civilization."

Julia Conley

NASA scientists were startled when a recent exploratory mission revealed a huge and rapidly-growing cavity on the underside of one of Antaractica's glaciers—signaling that the ice mass has been melting much faster than experts realized.

The cavity is two-thirds the size of Manhattan—large enough to have contained about 14 billion tons of ice before it melted, according to a report that was published in Science Advances on Thursday.

Much of that ice disappeared at an "explosive rate," scientists reported—likely melting only in the last three years.

"The size of a cavity under a glacier plays an important role in melting," lead author Pietro Milillo said in a statement. "As more heat and water get under the glacier, it melts faster."

The agency's Jet Propulsion Laboratory used ice-penetrating radar to explore the area beneath the Thwaites Glacier in West Antarctica, often called "one of the world's most dangerous glaciers" because its melting could significantly contribute to sea level rise. Scientists expected to find some relatively small gaps between the glacier and bedrock, but were unsettled by the 1,000-foot deep cavity the mission revealed.

As Common Dreams has reported, the study follows numerous recent scientific reports showing that ice in Antarctica is melting at a much faster rate than previously thought—as oceans warm more rapidly as well.

The melting of the Thwaites Glacier, which is the approximately the size of Florida, is already behind about four percent of global sea rise, according to the Jet Propulsion Laboratory. The disappearance of the ice mass would cause sea levels to rise by about two feet as well as making surrounding glaciers more likely to melt rapidly—which could cause an eight foot rise.

As Jon Gertner wrote at Wired last month, scientists have regarded the difficult-to-reach glacier with "dark speculation" in recent years:

If this mysterious glacier were to "go bad"—glaciologist-­speak for the process by which a glacier breaks down into icebergs and eventually collapses into the ocean—it might be more than a scientific curiosity. Indeed, it might be the kind of event that changes the course of civilization.

In the part of the Thwaites Glacier where the cavity has been detected, the scientists have observed a "complex pattern of retreat and ice melt" with parts of the glacier retreating about 2,625 feet per year.

"Understanding the details of how the ocean melts away this glacier is essential to project its impact on sea level rise in the coming decades," said Eric Rignot, a co-author of the NASA study.


Our work is licensed under Creative Commons (CC BY-NC-ND 3.0). Feel free to republish and share widely.

We've had enough. The 1% own and operate the corporate media. They are doing everything they can to defend the status quo, squash dissent and protect the wealthy and the powerful. The Common Dreams media model is different. We cover the news that matters to the 99%. Our mission? To inform. To inspire. To ignite change for the common good. How? Nonprofit. Independent. Reader-supported. Free to read. Free to republish. Free to share. With no advertising. No paywalls. No selling of your data. Thousands of small donations fund our newsroom and allow us to continue publishing. Can you chip in? We can't do it without you. Thank you.

Advocates Applaud as FTC Sues to Stop Microsoft-Activsion Mega-Merger

Biden's FTC, said one consumer campaigner, "is showing, once again, that it is serious about enforcing the law, reversing corporate concentration, and taking on the tough cases."

Brett Wilkins ·


Press Freedom Champions Renew Call for DOJ to Drop Charges Against Assange

"It is time for the Biden administration to break from the Trump administration's decision to indict Assange—a move that was hostile to the media and democracy itself."

Jessica Corbett ·


Oral Arguments Boost Fears of SCOTUS Buying Theory That Would 'Sow Elections Chaos'

"This reckless case out of North Carolina could explode the unifying understanding that power ultimately rests with the people of this country," one campaigner said of Moore v. Harper.

Jessica Corbett ·


War Industry 'Celebrating Christmas Early' as House Passes $858 Billion NDAA

"There is no justification to throw... $858 billion at the Pentagon when we're told we can't afford child tax credit expansion, universal paid leave, or other basic human necessities," said the consumer advocacy group Public Citizen. "End of story."

Brett Wilkins ·


GOP Florida Lawmaker Behind 'Don't Say Gay' Law Charged with Covid Relief Fraud

"It does not surprise me that someone who exploits queer kids for political gain would be charged with exploiting taxpayers for personal gain," said one Democratic state lawmaker.

Julia Conley ·

Common Dreams Logo