Underground sources of geothermal heat have been named as one reason Antarctica's Thwaites Glacier is melting.
Thwaites Glacier is a big contributor to the West Antarctic Ice Sheet, which is thought to be in danger of collapse in part because glaciers aren't sending it as much ice as has previously been the case. If the whole Ice Sheet melts, predictions suggest substantial sea level rises will result.
Just why Thwaites Glacier is less vigorous than has previously been the case is therefore of considerable interest, hence this new paper titled Evidence for elevated and spatially variable geothermal flux beneath the West Antarctic Ice Sheet. The paper's authors used “radar techniques to map how water flows under ice sheets”, a technique not previously explored. Doing so found “significant sources of geothermal heat under Thwaites Glacier” the paper's authors say “are distributed over a wider area and are much hotter than previously assumed.”
In other words, Thwaites has a hot butt that's making ice melt and getting the Western Antarctic Ice Shelf flustered.
Heat was measured at around 100 milliwatts per square meter and some hotspots checked in at 200 milliwatts per square meter. Both figures are above the 65 milliwatts per square meter found on Earth's continents. Volcanic activity is suspected to be the source of the heat.
The paper doesn't mention anthropogenic global warming. Not even once. But of course it's already being used as “evidence” to rebut theories the West Antarctic Ice Sheet's instability is caused by human activity.
Lead author Dustin M Schroeder hopes his work eventually helps “radio geophysical exploration of icy planets”. One of which might come in handy if the West Antarctic Ice Sheet collapses, no matter the reason. ®