Dive below the West Antarctic Ice Sheet and you’ll find fire as well as ice, says this article by Stephanie Pappas.
“A new study finds that subglacial volcanoes and other geothermal “hotspots” are contributing to the melting of Thwaites Glacier, a major river of ice that flows into Antarctica’s Pine Island Bay,” says Pappas.
“Areas of the glacier that sit near geologic features thought to be volcanic are melting faster than regions farther away from hotspots, said Dustin Schroeder, the study’s lead author and a geophysicist at the University of Texas.”
“This melting could significantly affect ice loss in the West Antarctic, an area that is losing ice quickly.”
Using radar data from satellites in orbit, the researchers found subglacial streams flowing beneath the Thwaites Glacier that were too full to be explained by flow from upstream. This indicated unusually high melt, said Schroeder.
When the researchers checked out the subglacial geology in the region, they found that fast-melting spots were disproportionately clustered near confirmed West Antarctic volcanoes, suspected volcanoes or other presumed hotspots.
Geothermal heat – not climate change! – is melting the glacier from below.
The minimum average heat flow beneath Thwaites Glacier is almost double the average of the rest of the continents, the researchers found. In some areas, average heat flow is more than triple the average. They found these sources are distributed over a wider area and are much hotter than previously assumed.
The extra melt caused by subglacial volcanoes could hasten the ice sheet’s flow toward the sea, Schroeder said.
Researchers have long known that volcanoes lurk under the ice of West Antarctica, because it is a seismically active region where East and West Antarctica are rifting apart, says Pappas. “In 2013, a team of scientists even found a new volcano beneath the West Antarctic Ice Sheet.” (Rifting is associated with the movement of magma and volcanic activity.)
The findings “show that the glacier sits on something more like a multi-burner stovetop with burners putting out heat at different levels at different locations,” says phys.org/news.
Schroeder and his colleagues at the Institute for Geophysics at The University of Texas at Austin (UTIG) plan to expand their study to other glaciers in the region.
Note: I’m really encouraged to learn about this study. Now I wish we could see more studies about how underwater volcanoes heat the seas. I’ve been harping about them for years. In fact, there’s an entire chapter about the unacknowledged importance of underwater volcanoes (entitled “Fish Stew”) in Not by Fire but by Ice.
Geothermal heat – not climate change! – is melting the glacier from below:
Thanks to Laurel, Alex Piccinini, Nelson Isada, Chris Beal, Jesus Eduardo Herrera Flores and Jack Hydrazine for these links
“A few weeks ago it was all because of Man Kind,” says Chris.