A new study recently published in the journal Science Advances may shade some light over the factors that accelerate the rate at which the West Antarctic ice sheet melts.
Scientists found that the geothermal heat radiating from beneath may drastically accelerate the region’s melting rate.
Yet, Prof. Andrew Fisher from the UC Santa Cruz argued that the new findings do not suggest that geothermal heating is the only phenomenon responsible for the Antarctic’s melting. Global warming still plays a major role, but the newly found internal factor greatly accelerates the process.
“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,”
the scientist explained.
Researchers hope that their study may provide an answer to why the West Antarctic ice sheet vanished so quickly over the past decade. Moreover, geothermal heating coming from below may also be the cause of the West Antarctic’s subglacial lakes and the quick transformation of ice sheet into ice streams.
Ice streams usually carry a lot of ice which later forms the floating ice shelves we observe around the melting ice sheet. On the other hand, researchers noted that their findings cannot be applied to the entire Antarctic ice sheet because geothermal heat flux greatly varies from one area to another beneath the ice sheet.
Prof Fisher even acknowledged that the recently detected heat influx from beneath the ice sheet may be the result of volcanic activity which produces a local heat source within the crust.
The study was part of a larger project called Whillans Ice Stream Subglacial Access Research Drilling (WISSARD), which was sponsored by the National Science Foundation.
During their research, scientists used a special probe that can measure geothermal heat in the sediments located underneath the Subglacial Lake Whillans. They also used a hot-water driller to penetrate the ice sheet and allow the probe reach the bottom of the subglacial lake. The probe was immersed into the lake’s sediments where it measured the changes in heat levels with depth.
Surprisingly the probe revealed that the temperature change rate there was five times greater than on land. Researchers concluded that there is a rapid geothermal heat influx affecting the bottom of the West Antarctic.
That heating, scientists explained, melts the bottom of the ice sheet, which then feeds a network of subglacial lakes and streams that accelerates even more the region’s melting rate.
Image Source: Daily Mail