Hidden Rift Deep Beneath the Ice May be Accelerating Melting in West Antarctica
Scientists with the British Antarctic Survey have discovered a rift valley that is one mile deep. The valley is hidden deep below the Ferrigno Ice Stream in West Antarctica, an extremely remote region seen only once previously by human eyes in 1961. They found that this rift basin is connected to the ocean, allowing the ocean to penetrate into the continent. The Southern Sea impacting the ice has a warming effect, despite its cold temperatures. This has tremendous implications, as the West Antarctic Ice Sheet is melting at a faster rate than any other part of the continent.
The lead author for the study, Dr. Robert Bingham, glaciologist at the University of Aberdeen, discovered the rift valley while doing fieldwork in 2010. He set out to find out why some melting on the coastline was occurring more rapidly in some areas than others. It was essential to assess the conditions not only in the atmosphere and ocean, but beneath the ice surface.
His team gathered data using ice-penetrating radar driven by skidoos over a distance of 1,500 miles. By way of comparison, this distance is greater than the distance between London and Athens, as well as between Los Angeles and Houston.
The radar picked up an extremely large rift, sinking a mile below the surrounding land. "If you stripped away all of the ice here today, you’d see a feature every bit as dramatic as the huge rift valleys you see in Africa and in size as significant as the Grand Canyon," said Binham. "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 most amazing part of the discovery is that the valley aligns perfectly with records of ice-surface lowering caused by melting observed via satellites over the last two decades. This incredible finding will help scientists predict the patterns of ice loss in Western Antarctica in the years to come.
The study has been published in the journal, Nature.
To view videos of this study, click here.
Iceberg image via Shutterstock