East Antarctica has long been hailed as a bastion of continuity in the rapidly unraveling Antarctic. The West Antarctic is the landscape where ice goes to die, while the higher elevation, colder eastern portion of the continent has been viewed as a stable landscape largely separated from rising temperatures and warm ocean currents.
But new research shows that the few soft spots in the impervious ice sheet are categorically losing ice. While it’s not a full-blown meltdown like what could be playing out in West Antarctica, it’s a reminder that no corner of the planet—not even the coldest one—is impervious to the impacts of climate change.
The study released last week in Geophysical Research Letters chronicles the past 15 years at two glaciers in East Antarctica. The Moscow University and Totten glaciers descend from the East Antarctic ice sheet down to the sea. They act as dams to ice on land; if that ice all melted into the ocean, it would raise sea levels more than 16 feet (five meters). The rest of East Antarctica is an even stash of ice, one we really need to learn more about.
“The East Antarctic ice sheet contains much more ice and sea level potential than any other ice sheet by far, making it of crucial global significance,” Yara Mohajerani, a PhD candidate at the University of California, Irvine who led the study, told Earther.
Scientists have suspected these two glaciers have been losing mass for a while, driven by warm ocean water circulating under them, similar to the processes at play in West Antartica driving huge losses. But it’s been hard to get a handle on just how much mass, because they drain a huge basin, and the mass losses are still small relative to the size of said basin. To overcome that, the researchers developed a novel technique using Gravity Recovery and Climate Experiment (GRACE), a NASA satellite that measures small changes in gravity.
The thing about Earth is it’s not a nice, spherical marble. It’s a lumpy-ass gourd of a planet and its shape is ever changing. All those shifting lumps means that gravity also changes in tiny ways. Not in ways that you and I can feel, mind you, but in ways that satellites can precisely measure from space.
That’s the whole point of GRACE, which lasted from 2002 to 2017, and the follow-up mission that launched earlier this year. The new study used the 15 years of GRACE data and a nifty set of calculations to get a finely calibrated set of results showing that the glaciers are unequivocally losing mass.
For the 15 years of GRACE measurements, the glaciers are shedding 18.5 gigatons of ice annually. That’s enough ice to fill 7.4 million Olympic-sized pools.
“This multisensor study provides multiple lines of evidence that the changes taking place in that part of East Antarctica are real and significant,” Eric Rignot, a NASA Jet Propulsion Laboratory climate scientist involved with the research, told Earther. “This study is part of a growing number of evidence that East Antarctica is an important part of the evolution of Antarctica in a warmer climate.”
Overall, Antarctica has shed 3 trillion (yes, trillion) tons of ice since 1992. The losses in this corner of Antarctica are dwarfed by losses elsewhere. There’s also evidence that East Antarctica as a whole may be gaining mass through snowfall, given its high, frigid nature.
But the few glaciers that do descend down from it are still worthy of scrutiny. Previous research has shown that East Antarctic glaciers have been wiped out in the past during times when atmospheric carbon dioxide levels were roughly on par with the ones we’ve built up today through human activities.
Chad Greene, a University of Texas researcher who has studied the water undercutting Totten Glacier’s floating ice shelf, said the new research shows how the melt there is affecting the rest of the glacier.
“They’re showing the long-term response of the ice sheet to the types of changes I was observing in Totten Ice Shelf, and we see once again that the Aurora Subglacial Basin is losing ice, driven by changes in ocean temperature and circulation at the coast,” he told Earther. “It’s basically the same picture we’ve been seeing for a decade now, but Mohajerani et al. bring it much more clearly into focus: Totten Glacier and the Aurora Subglacial Basin it drains are losing ice, no matter how you look at it.”