Scientists at the University of California, Santa Cruz (UCSC) have discovered that the unstable feature of the ice sheet in the West Antarctic could potentially be caused by a continued flow of heat from geothermal sources located deep beneath its surface.
Andrew Fisher, an Earth and planetary sciences professor at UCSC, led a team of researchers in conducting a lengthy probe in order to measure the heat flow coming from sediments below the sheet of ice.
They found that a considerable amount of heat travels upward from these geothermal sources toward the base of the structure.
Fisher, however, pointed out that the heating from the Earth noted in their study does not provide an explanation for the loss of ice from West Antarctica recorded in previous research.
He said that the sheet of ice was formed through a natural system that features a flux of geothermal heat emanating from below. This observation could be used to help determine why the ice sheet is very unstable.
Fisher added that if this occurrence is combined with the effects of global warming, the situation in the area will begin to change rapidly.
The geothermal heating observed by Fisher and his team could explain the existence of large sub-glacial lakes in the region that were detailed by other researchers. The amount of heating could also be responsible for the high glacial stream flows seen on the ice sheet. These flows provide lubrication that could help increase the rate of melting of the ice.
The UCSC researchers said the measurements that they were able to document came from a single location below the sheet of ice.
"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," Fisher said.
"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 the flux of geothermal heat they measured was at 285 milliwatts for every square meter, which the professor compared to the heat given off by one Christmas light for every square meter.
UCSC researcher and study co-author Slawek Tulaczyk said that it is vital to extract the correct measurements in order for scientists to accurately forecast how the ice sheet in the West Antarctic will behave in years to come. This includes determining how much of the ice sheet is melting, how fast the streams of ice flow and the potential impact it could have on the rise in sea level.
The findings of the UCSC study are profiled in the journal Science Advances.
Photo: Andreas Kambanis | Flickr
