Thwaites Glacier: Significant Geothermal Heat Beneath the Ice Stream
Researchers map the geothermal heat flow in West Antarctica; a new potential weak spot in the ice sheet’s stability is identified.
Ice losses from Thwaites Glacier in West Antarctica are currently responsible for roughly four percent of the global sea-level rise. This figure could increase, since virtually no other ice stream in the Antarctic is changing as dramatically as the massive Thwaites Glacier. Until recently, experts attributed these changes to climate change and the fact that the glacier rests on the seafloor in many places, and as such comes into contact with warm water masses. But there is also a third, and until now, one of the most difficult to constrain, influencing factors. In a new study, German and British researchers have shown that there is a conspicuously large amount of heat from Earth’s interior beneath the ice, which has likely affected the sliding behaviour of the ice masses for millions of years. This substantial geothermal heat flow, in turn, is due to the fact that the glacier lies in a tectonic trench, where the Earth’s crust is significantly thinner than it is e.g. in neighbouring East Antarctica.
[...] Unlike East Antarctica, West Antarctica is a geologically young region. In addition, it doesn’t consist of a large contiguous land mass, where the Earth’s crust is up to 40 kilometres thick, but instead is made up of several small and for the most part relatively thin crustal blocks that are separated from each other by a so-called trench system or rift system. In many of the trenches in this system, the Earth’s crust is only 17 to 25 kilometres thick, and as a result a large portion of the ground lies one to two kilometres below sea level. On the other hand, the existence of the trenches has long led researchers to assume that comparatively large amounts of heat from Earth’s interior rose to the surface in this region. With their new map of this geothermal heat flow in the hinterland of the West Antarctic Amundsen Sea, experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) and the British Antarctic Survey (BAS) have now provided confirmation.
[...] Nevertheless, the heat flow could be a crucial factor that needs to be considered when it comes to the future of Thwaites Glacier. According to Gohl: “Large amounts of geothermal heat can, for example, lead to the bottom of the glacier bed no longer freezing completely or to a constant film of water forming on its surface. Both of which would result in the ice masses sliding more easily over the ground. If, in addition, the braking effect of the ice shelf is lost, as can currently be observed in West Antarctica, the glaciers’ flow could accelerate considerably due to the increased geothermal heat.”
Journal Reference:
Dziadek, Ricarda, Ferraccioli, Fausto, Gohl, Karsten. High geothermal heat flow beneath Thwaites Glacier in West Antarctica inferred from aeromagnetic data [open], Communications Earth & Environment (DOI: 10.1038/s43247-021-00242-3)
(Score: 5, Informative) by Rosco P. Coltrane on Wednesday August 18 2021, @10:52PM (1 child)
The excerpt quoted in the story is rather misleading. It might lead climate change deniers to feel vindicated, when in reality, TFA says this:
In other words, the glacier was always able to slide more easily due to the heat source underneath it, but so far it didn't because the ice shelf at the end prevented it from moving downward very fast. Now that's we've weakened the ice shelf with man-made global warming, the glacier isn't contained anymore and might accelerate more than anticipated.
It's more of a "Oh shit, global warming is worse than we thought" story than anything else.
(Score: 0) by Anonymous Coward on Wednesday August 18 2021, @11:11PM
How dare we!
(Score: 0, Troll) by Anonymous Coward on Wednesday August 18 2021, @11:09PM
Nonsense, it entirely the result of man-made global warming.
(Score: 4, Insightful) by oumuamua on Thursday August 19 2021, @02:08AM (2 children)
'Doomsday Glacier' - a rogue state [Afghanistan or N. Korea] holds the world hostage by threatening to blow up an atomic bomb over the vulnerable Thwaites Glacier anchor point thereby triggering immediate and catastrophic sea level rise. Can the hero [Bond or Furious team or IMF] overcome impossible odds to save the day?
(Score: 0) by Anonymous Coward on Thursday August 19 2021, @05:32AM
No.
Next movie idea.
(Score: 2) by DeathMonkey on Thursday August 19 2021, @04:02PM
What's interesting is that no matter what team you pick, Vin Diesel will be involved.