What is the Doomsday Glacier/Thwaites Glacier?
Thwaites Glacier, sometimes referred to as the Doomsday Glacier is an unusually broad and vast Antarctic glacier flowing into the Pine Island Bay. It is a part of the Amundsen Sea, east of Mount Murphy, on the Walgreen Coast of Marie Byrd Land. Its surface speeds exceed 2 kilometres per year near its grounding line. Its fastest-flowing grounded ice is centred between 50 and 100 kilometres east of Mount Murphy. It was named by the Advisory Committee on Antarctic Names in 1967 after Fredrik T. Thwaites, a glacial geologist, geomorphologist and professor emeritus at the University of Wisconsin–Madison.
Why is the glacier so important?
Thwaites is almost as big as Britain.
It’s a majestic sight, with its front, or “ice shelf”, pushing far out to sea. But satellite monitoring indicates this glacier is melting at an accelerating rate.
In the 1990s it was losing just over 10 billion tonnes of ice a year. Today, it’s more like 80 billion tonnes. The cause of the melting is thought to be the influx of relatively warm bottom-water drawn in from the wider ocean.
Currently, Thwaites’ ice loss contributes approximately 4% to the annual rise in global sea-levels, with the potential to add 65cm in total should the whole glacier collapse.
Incidentally, no-one thinks this will happen in the short-to-medium term, but Thwaites is considered particularly vulnerable in a warming world.
What happened NOW?
Scientists studying a giant mass of ice in Antarctica known as the “doomsday glacier” believe they have discovered why it is melting so rapidly and pushing up sea levels.
The UK and the US joined forces in 2019 to investigate Thwaites.
Their scientists sailed a ship equipped with an echo-sounder right up to the glacier’s ice cliffs, to trace the shape of the seabed below. A team of UK and US researchers has found a series of deep channels beneath Thwaites Glacier thought to be acting as pathways for warm ocean water to melt the underside of the ice.
To measure small variations in the pull of gravity, a plane was also flown back and forth across the shelf. These deviations reflected the seafloor’s undulations beneath the shelf.
The two datasets taken together now provide the best view yet of Thwaites’ underlying topography. In addition, they trace the path of a network of deep channels that cut through a ridge before joining up to form a major cavity under the ice shelf.
More about the recent Doomsday glacier melting discoveries
“The connected channels that we’ve mapped in detail for the first time are the potential pathways for deep-ocean warm water to get in and do damage at that point where the glacier is still grounded on the seabed, where it begins to lift up and float,” explained BAS colleague Dr Tom Jordan, “but also to melt the base of the ice shelf, which if you weaken will make the ice further upstream in the glacier flow faster.”
“I was shocked to fly over the glacier and see all the debris left behind as the ice shelf has collapsed – it was stunning,” said Dr Tom Jordan, an aero-geophysicist from the British Antarctic Survey (BAS) who led the airborne survey.
He told The Independent: “You look out the window and you see the broken-up fragments of the former ice shelf. It was breathtaking. It brought home how much how much this natural system has been damaged and is breaking up.”
Moreover, Dr Jordan believes that carbon emissions from human activity have contributed to the warming of the ocean in Antarctica. Moreover, he says “It’s generally accepted that the warming of the ocean is part of what is driving the retreat at Thwaites Glacier,” he said.
“It is part of the changing climatic system, which is an anthropogenic effect. That’s the scientific consensus – that the changes relate to human-caused climate change.”
“For the first time we have a clear view of the pathways along which warm water can reach the underside of the glacier, causing it to melt and contribute to global sea-level rise.”
With the doomsday glacier melting, the impact of climate change has been alarmingly loud. What do you think?