Study finds surprisingly high geothermal heating beneath West Antarctic Ice Sheet

[mackdaddy]

The amount of heat flowing toward the base of the West Antarctic ice sheet from geothermal sources deep within the Earth is surprisingly high, according to a new study led by UC Santa Cruz researchers. The results, published July 10 in Science Advances, provide important data for researchers trying to predict the fate of the ice sheet, which has experienced rapid melting over the past decade.

Lead author Andrew Fisher, professor of Earth and planetary sciences at UC Santa Cruz, emphasized that the geothermal heating reported in this study does not explain the alarming loss of ice from West Antarctica that has been documented by other researchers. "The ice sheet developed and evolved with the geothermal heat flux coming up from below—it's part of the system. But this could help explain why the ice sheet is so unstable. When you add the effects of global warming, things can start to change quickly," he said.

High heat flow below the West Antarctic ice sheet may also help explain the presence of lakes beneath it and why parts of the ice sheet flow rapidly as ice streams. Water at the base of the ice streams is thought to provide the lubrication that speeds their motion, carrying large volumes of ice out onto the floating ice shelves at the edges of the ice sheet. Fisher noted that the geothermal measurement was from only one location, and heat flux is likely to vary from place to place beneath the ice sheet.

"This is the first geothermal heat flux measurement made below the West Antarctic ice sheet, so we don't know how localized these warm geothermal conditions might be. This is a region where there is volcanic activity, so this measurement may be due to a local heat source in the crust," Fisher said.

http://phys.org/news/2015-07-surprisingly-high-geothermal-beneath-west.html#nRlv

It does not look like a lot of melting, but any liquid water under these ice sheets could act as a lubricant to increase movement to the oceans, and seems to be enough to need to be added to the scientist melt models.