As It Happens

Decades-old film reveals Antarctica glacier is melting faster than scientists thought

Newly digitized ice-penetrating radar records captured on 35mm film in the 1970s revealed Antarctica’s most important glacier is thawing faster than previously thought.

The restored film from the '70s offers scientists new ways to gauge the rate of climate change in Antarctica

A still frame shows an aerial view of Whitmore Mountain in central West Antarctica. The frame is part of a restored collection of archival film scientists are using to better understand climate change. (Submitted by David Drewry)
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Transcript

Scientists knew Antarctica's Thwaites Glacier was thawing, they just had no idea how quickly the process was happening.

But thanks to radio glaciologist Dustin Schroeder's painstaking efforts to digitize some old film reels, researchers now have a new window into the severity of the problem.

"What this allows us to do is see this change in that ice shelf over, in this case, about 40 years," Schroeder told As It Happens host Carol Off.

"[We can] look at and understand and reproduce that change, and that will give us more confidence in our capacity to make our projections into the future."

Schroeder and his colleagues at California's Stanford University based their study on hundreds of canisters of film reels that were stored in the Scott Polar Research Institute at the University of Cambridge in the U.K. The findings were published Monday in the journal Proceedings of the National Academy of Sciences.

Schroeder says the films, shot in the 1970s, laid the foundation for his field of radio glaciology. But until now, the decades-old data has been difficult to access. 

Dustin Schroeder, foreground, and art historian Jessica Daniel splice decades-old film containing radar measurements of Antarctica into a reel, in preparation for digital scanning, at the Scott Polar Research Institute. (Submitted by Dustin Schroeder)

Schroeder had to manually wind the film reels by hand using vintage equipment that he bought off eBay — by outbidding "hipster filmmakers."

But once the film was finally digitized in high resolution, Schroeder says important new details emerged.

"We are able to directly compare what not only the thickness but the shape of that ice shelf is in the archival data we scanned versus the modern data," Schroeder said.

"We're able to see that in areas it is thinning much more than the average signal you can get by looking at it from satellite."

The Thwaites Glacier in Antarctica has been eaten away from below by a warming of sea waters around the frozen continent. (NASA/Reuters)

Schroeder says the next step is to use these new measurements to try to understand how the ice sheet will respond — and is already responding — to rapid changes in climate.

"We know already that one of the big drivers of change in the entire region where Thwaites exists is warm ocean water melting ice shelves and the grounding lines of ice sheets," Schroeder said.

"We take those observations, including observations people are making in Antarctica now, and put those into ice sheet models to make projections of how the ice sheets will evolve."

Schroeder says those projections will be even more accurate when referenced against the newly digitized archival films.

"[It] gives you a much finer scale process to observe, understand, model and reproduce than the sort of average measurement you got from satellite altimetry over the whole area."

Hundreds of rolls of vintage film had to be condensed into 75 reels before they could be digitally scanned. (Submitted by Dustin Schroeder)

The films may confirm an even harsher reality of the effects of climate change, but Schroeder says we're lucky the archive exists and that ultimately the study gives him hope.

"[It's] a real privilege to be tactilely touching and archiving and preserving the foundational measurements of my field. That's inspiring," Schroeder said.

"The fact that we were lucky enough to get this snapshot of one of the most dynamically changing parts of one of the most important potentially unstable glaciers gives me a lot of comfort and hope that we will get those numbers better and we will be able to make plans and take actions as a society."

Written by John McGill and Kate Cornick. Interview with Dustin Schroeder produced by Kate Cornick. 

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