A study released last week by researchers at the University of Texas reveals the West Antarctic ice sheet indeed appears to be melting – but human activity’s got nothing to do with it.
The study, which attempts to assess glacial erosion of Antarctica’s massive Thwaites Glacier, was conducted by a research team at the university’s Institute for Geophysics. The Texas scientists found that tidal forces are physically eroding glacial material, and that geothermal heat from subglacial magma is exacerbating the pace of that process.
The Thwaites Glacier, according to researchers, is about the size of Florida in area and up to 4,000 meters thick. Understanding the forces behind the glacier’s retreat is “crucial to understanding what might happen to the West Antarctic Ice Sheet,” the research team said in a press release, which makes no mention of man-made global warming:
The cause of the variable distribution of heat beneath the glacier is thought to be the movement of magma and associated volcanic activity arising from the rifting of the Earth’s crust beneath the West Antarctic Ice Sheet.
… Because its interior connects to the vast portion of the West Antarctic Ice Sheet that lies deeply below sea level, the glacier is considered a gateway to the majority of West Antarctica’s potential sea level contribution.
The collapse of the Thwaites Glacier would cause an increase of global sea level of between 1 and 2 meters, with the potential for more than twice that from the entire West Antarctic Ice Sheet.
“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,” added lead author Dusty Schroeder.
The new research “significantly change[s] the understanding of conditions beneath the West Antarctic Ice Sheet where accurate information has previously been unobtainable,” the team said, noting that the geothermal activity beneath the structure is “much hotter than previously assumed.”