Andrew Freedman
Fri, January 21, 2022
Researchers like David Holland, an atmospheric scientist at New York University, are in a race to understand the fate of a massive glacier in West Antarctica that has earned a disquieting nickname: "The Doomsday Glacier."
Why it matters: Studies show the Thwaites Glacier (its official name) could already be on an irreversible course to melt during the next several decades to centuries, freeing up enough inland ice to raise global sea levels by at least several feet.
Driving the news: Speaking via satellite phone Thursday aboard an icebreaker navigating through thick sea ice near West Antarctica, Holland said his research team aims to gain a better understanding of what is taking place near the glacier's grounding line. That is where the glacial ice meets the seafloor, or where floating ice meets land ice.
The big picture: The conditions there will help scientists model the glacier's likely future.
The topography of West Antarctica's seafloor is such that if the ice shelf were to significantly melt or even collapse, warm water could flow well inland, melting land-based ice.
Meaning if the ice shelf breaks up, it will open the path for the massive quantities of inland ice that it holds back, like a doorstop or a cork in a wine bottle, to flow faster into the sea.
This would raise sea levels, with potentially catastrophic consequences in coastal cities worldwide. Thwaites Glacier's meltwater already comprises about 4% of global annual sea-level rise.
Some studies have shown that much of West Antarctica may already be on an unstoppable melt pathway, but the specific timing is unclear.
Holland's work is part of the International Thwaites Glacier Collaboration, a multinational push to urgently gain a better understanding about Thwaites' fate, and with it, that of some of the world's most populated cities, from New York to Mumbai.
How it works: Holland's team of scientists and engineers plans to use hot water drilling to generate boreholes through the ice shelf to observe the water below.
Scientists will also use small, unmanned submarines to take readings under the ice to find out more about the water temperature, salinity and ocean currents in areas that are critical for stabilizing the glacier.
If ocean temperatures just beneath the ice shelf are above freezing, it would melt the ice shelf from below. This has been taking place in parts of Thwaites, based on satellite readings and extensive field studies carried out so far.
Flashback: In December, scientists affiliated with the international research effort Holland is participating in announced they detected new cracks in Thwaites' Eastern Ice Shelf.
They warned parts of that shelf could collapse in as little as five years, accelerating the movement of inland ice to the sea and eventually causing sea levels to rise by several feet.
Between the lines: The eastern Thwaites discovery was an unnerving surprise since it is a part of the ice shelf that was previously thought to be more stable. But the main action is in the western part of the ice shelf, Holland said, where he is now headed.
"Western Thwaites moves faster, it's much deeper and it cuts more into the inland," he said. "It could fall apart quickly, in decades, or it could be centuries. And the only way to really know that is through this research."
The bottom line: "I'm here at the end of the Earth, but I'm not actually very far away from where you are," Holland said. "Everything is connected, and this ice that seems far away is intricately a part of your planet and your life."
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