Antarctica’s ‘Doomsday Glacier’ keeps scientists at bay with iceberg and sea ice
Attempts to study the deteriorating Florida-sized glacier that could raise sea levels by 2ft if it breaks off are being frustrated
The deteriorating Florida-sized Thwaites glacier has recently shed an iceberg that is blocking two research ships filled with dozens of scientists.
Associated Press
Wed 2 Feb 2022 20.37 GMT
Antarctica’s so-called Doomsday Glacier, nicknamed because it is huge and coming apart, is thwarting an international effort to figure out how dangerously vulnerable it is.
A large iceberg has broken off the deteriorating Thwaites glacier and, along with sea ice, it is blocking two research ships with dozens of scientists from examining how fast its crucial ice shelf is falling apart.
Scientists from around the world are part of a $50m international effort to study the Florida-sized glacier by land, sea and below for the brief time the remote ice is reachable during the Antarctic summer.
Plans to examine the glacier’s crucial ice shelf have not been stopped but are sidetracked a bit, officials said.
This was the last of three international scientific expeditions aimed at the vulnerable ice shelf, said British Antarctic Survey geophysicist Rob Larter, chief scientist of the first research mission.
Scientists watch giant ‘doomsday’ glacier in Antarctica with concern
David Holland, an environmental scientist at New York University, who planned to drill deep through the Thwaites ice shelf to measure the water’s warmth below it, is achingly close but not quite there.
Improvising, Holland decamped at the nearby Dotson ice shelf to do his research where no human had been before. He is hoping that along that blinding white ice and its rugged frozen cliffs he can learn about the unseen warm ocean water nibbling away at both Dotson and Thwaites from below. The smaller Dotson ice shelf is about 87 miles (140km) west of the Thwaites ice shelf.
“Nobody can get to Thwaites this year,” Holland told the Associated Press on Monday. “We tried to cut through it for a week. Couldn’t do it. So we’re next to it.”
Thwaites is spawning more icebergs as it falls apart, Holland said. This iceberg used to be the tongue or leading edge of Thwaites until it broke off about 20 years ago, Larter said. It measures about 43 miles by 28 miles, almost the size of Rhode Island, according to the National Snow and Ice Data Center.
Much of the problem is that loads of sea ice have gravitated around the huge iceberg. And that’s ironic – and troublesome for researchers – because overall Antarctic sea ice is unusually low for this time of year, Larter said.
The key to the future of Thwaites is the ice shelf and its tongue. These edges with warm water underneath border the ocean and provide “back support” that holds the rest of the glacier in place, preventing it from falling into the sea, Holland said.
What worries scientists is that the leading edge of the huge glacier is breaking apart in many places. Even though total collapse of the glacier could take hundreds or thousands of years, the edge is falling apart much sooner. And if that goes, researchers fear nothing may stop the rest from doing the same.
“I think the ice shelf will be gone in a matter of years to decades,” Holland said. “But the actual inland ice, that’s the really unknown question.”
The RRS Sir David Attenborough arrives in Portsmouth to take on fuel before departing from the UK for its maiden voyage to Antarctica. The state-of-the-art research vessel will transfer station teams, food, cargo and fuel to British Antarctic Survey's five research stations as well as transporting essential science equipment for studies on unstable glaciers before returning to the UK in June 2022. Photo by Finnbarr Webster/Getty Images
Is the world’s most important glacier on the brink of collapse? – podcast
Read moreIf all of Thwaites collapses, it could raise seas around the globe more than two feet (65cm) but that could take hundreds of years, scientists say.
“Ultimately over time it’s going to rewrite the global coastline,” Holland said.
Ian Joughin, a University of Washington ice scientist who is not part of the research consortium, cautioned that while Thwaites is a big concern, especially the collapse of giant ice cliffs, the earliest his computer simulations show that happening in 200 years from now.
“We need to take these glaciers seriously without sounding like Chicken Little,” Joughin said in an email.
But if Thwaites goes, neighboring glaciers could follow, said Paul Cutler, director of the US National Science Foundation glaciology program.
“Once you lose Thwaites you also start draining other ice into that basin,” Cutler said. “And so in all the forecasting models, it tends to cause the rest of West Antarctica to collapse over time scales of thousands of years.”
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