July 27, 2012
Field camp on Ferrigno Ice Stream. Courtesy of the University of Aberdeen
Scientists from the University of Aberdeen and British Antarctic Survey (BAS) made the discovery below Ferrigno Ice Stream, an extremely remote area that has been visited only once previously. They used ice-penetrating radar to map the valley.
Site of the rift valley (marked with black box, within the red box).
"This is at odds with the flat ice surface that we were driving across – without these measurements we would never have known that it was there."
The discovery is important because it may help explain why the West Antarctic Ice Sheet is losing ice at a faster pace than the rest of Antarctica. Some glaciers in the region are shrinking by more than a meter (3 feet) per year.
"What this study shows is that this ancient rift basin, and the others discovered under the ice that connect to the warming ocean can influence contemporary ice flow and may exacerbate ice losses by steering coastal changes further inland," said study co-author and geophysicist Fausto Ferraccioli from British Antarctic Survey.
The scientists say the work can help improve forecasts for future sea level rise.
"Thinning ice in West Antarctica is currently contributing nearly 10 per cent of global sea level rise," said David Vaughan of the British Antarctic Survey. "It's important to understand this hot spot of change so we can make more accurate predictions for future sea level rise."