The Antarctic Thwaites glacier, considered the key to evaluating rising sea levels, is "actively melting in response to geothermal flux" from volcanoes' magma, a new study from the Institute for Geophysics at University of Texas, Austin finds.
Researchers found that areas where the glacier showed greatest geothermal flux corresponded with "magmatic migration and volcanism."
Unfortunately for global warming enthusiasts, geothermal warming is nature's handiwork.
This study found under the glacier a "minimum average geothermal heat flow [of]... about 100 milliwatts per square meter, with hotspots over 200 milliwatts per square meter." Contrast that with the earth's continents, that have an "average heat flow... less than 65 milliwatts per square meter.
Using radar techniques to map how water flows under ice sheets, UTIG researchers were able to estimate ice melting rates and thus identify significant sources of geothermal heat under Thwaites Glacier. They found these sources are distributed over a wider area and are much hotter than previously assumed.
The geothermal heat contributed significantly to melting of the underside of the glacier, and it might be a key factor in allowing the ice sheet to slide, affecting the ice sheet's stability and its contribution to future sea level rise.
Until now, scientists had been unable to measure the strength or location of heat flow under the glacier. Current ice sheet models have assumed that heat flow under the glacier is uniform like a pancake griddle with even heat distribution across the bottom of the ice.
Scientists used a "combination of radar sounding and subglacial routing" and airborne radar sounding data.
The new findings present a novel problem. "The combination of variable subglacial geothermal heat flow and the interacting subglacial water system could threaten the stability of Thwaites Glacier in ways that we never before imagined," Lead Researcher David Schroeder said.