August 30, 2013
Massive Canyon Discovered Beneath Greenland Ice Sheet
[ Watch the Video: Greenland’s Mega Canyon ]
redOrbit Staff & Wire Reports - Your Universe Online
Lead author Jonathan Bamber, a professor at the University of Bristol’s School of Geographical Sciences, and colleagues report the canyon is at least 460 miles (750km) long, up to 2,600 feet (800m) deep in places.
Furthermore, the hidden valley, which is on the same scale as segments of the Grand Canyon, is believed to actually predate the ice sheet that has covered Greenland for the past few million years.
According to BBC News Environment Analyst Roger Harrabin, it was discovered accidentally by scientists researching climate change in the region. Those researchers were mapping Greenland’s bedrock by radar when they made the discovery.
“With Google Streetview available for many cities around the world and digital maps for everything from population density to happiness one might assume that the landscape of the Earth has been fully explored and mapped. Our research shows there's still a lot left to discover,” Bamber said in a statement.
[ Watch the Video: Animation of Greenland Canyon ]
Thousands of miles of airborne radar data, originally collected by US, UK and German investigators, was analyzed leading up to the discovery. A large portion of that information was collected between 2009 and 2012 as part of NASA’s Operation IceBridge, an airborne mission designed to monitor changes in polar ice.
The US space agency reports one of the project’s main scientific instruments, the Multichannel Coherent Radar Depth Sounder, is capable of seeing through vast layers of ice to measure its thickness and the shape of the bedrock located below. While analyzing the radar data, Bamber’s team discovered a continuous bedrock canyon extending from near the center of the island to the Petermann Glacier fjord in northern Greenland.
“It is quite remarkable that a channel the size of the Grand Canyon is discovered in the 21st century below the Greenland ice sheet. It shows how little we still know about the bedrock below large continental ice sheets,” explained Michael Studinger, IceBridge project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
The study authors, whose work was funded by the European Union’s ice2sea project and the UK Natural Environment Research Council (NERC), believe the canyon could play an essential role in transporting subglacial meltwater from the Greenland interior to the ice sheet’s edge. Prior to the presence of the ice sheet, evidence suggests water flowed in the canyon and that it was a major river system.
“A discovery of this nature shows that the Earth has not yet given up all its secrets,” said Professor David Vaughan, ice2sea coordinator at the British Antarctic Survey in Cambridge. “A 750km canyon preserved under the ice for millions of years is a breathtaking find in itself, but this research is also important in furthering our understanding of Greenland’s past. This area’s ice sheet contributes to sea level rise and this work can help us put current changes in context.”