Tech

August 31, 2013

NASA data reveals mega-canyon under Greenland ice sheet

Data from a NASA airborne science mission reveals evidence of a large and previously unknown canyon hidden under a mile of Greenland ice.

The canyon has the characteristics of a winding river channel and is at least 460 miles long, making it longer than the Grand Canyon. In some places, it is as deep as 2,600 feet, on scale with segments of the Grand Canyon. This immense feature is thought to predate the ice sheet that has covered Greenland for the last few million years.

“One might assume that the landscape of the Earth has been fully explored and mapped,” said Jonathan Bamber, professor of physical geography at the University of Bristol in the United Kingdom, and lead author of the study. “Our research shows there’s still a lot left to discover.”

Bamber’s team published its findings Thursday in the journal Science.

The scientists used thousands of miles of airborne radar data, collected by NASA and researchers from the United Kingdom and Germany over several decades, to piece together the landscape lying beneath the Greenland ice sheet.

A large portion of this data was collected from 2009 through 2012 by NASA’s Operation IceBridge, an airborne science campaign that studies polar ice. One of IceBridge’s scientific instruments, the Multichannel Coherent Radar Depth Sounder, can see through vast layers of ice to measure its thickness and the shape of bedrock below.

In their analysis of the radar data, the team discovered a continuous bedrock canyon that extends from almost the center of the island and ends beneath the Petermann Glacier fjord in northern Greenland.

At certain frequencies, radio waves can travel through the ice and bounce off the bedrock underneath. The amount of times the radio waves took to bounce back helped researchers determine the depth of the canyon. The longer it took, the deeper the bedrock feature.

“Two things helped lead to this discovery,” said Michael Studinger, IceBridge project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “It was the enormous amount of data collected by IceBridge and the work of combining it with other datasets into a Greenland-wide compilation of all existing data that makes this feature appear in front of our eyes.”

The researchers believe the canyon plays an important role in transporting sub-glacial meltwater from the interior of Greenland to the edge of the ice sheet into the ocean. Evidence suggests that before the presence of the ice sheet, as much as 4 million years ago, water flowed in the canyon from the interior to the coast and was a major river system.

“It is quite remarkable that a channel the size of the Grand Canyon is discovered in the 21st century below the Greenland ice sheet,” said Studinger. “It shows how little we still know about the bedrock below large continental ice sheets.”

The IceBridge campaign will return to Greenland in March 2014 to continue collecting data on land and sea ice in the Arctic using a suite of instruments that includes ice-penetrating radar.




All of this week's top headlines to your email every Friday.


 
 

 
NASA photograph

NASA, partners test unmanned aircraft systems

NASA photograph NASA’s Ikhana is being used to test a system that will allow uncrewed aircraft to fly routine operations within the National Airspace System. NASA, working with government and industry partners, is testing...
 
 
NASA photograph

NASA-developed air traffic management tool flies into use

NASA photograph NASA Future Flight Central is a national Air Traffic Control/Air Traffic Management (ATC/ATM) simulation facility. The two-story facility offers a 360-degree full-scale, real-time simulation of an airport, where...
 
 
NASA photograph

Robotics teams prepare to compete for $1.5 million in NASA Challenge

NASA photograph The Los Angeles team Survey’s robot is seen as it conducts a demonstration of the level two challenge during the 2014 NASA Centennial Challenges Sample Return Robot Challenge, Thursday, June 12, 2014, at t...
 

 

NASA invests in future of aviation with supersonic research projects

Quieter, greener supersonic travel is the focus of eight studies selected by NASAís Commercial Supersonic Technology Project to receive more than $2.3 million in funding for research that may help overcome the remaining barriers to commercial supersonic flight. The research, which will be conducted by universities and industry, will address sonic booms and high-altitude emissions...
 
 
afrl-sensors

Sensors Directorate co-sponsors autonomous aerial vehicle competition

Members from the University of Toledo, Ohio, team make adjustments to their multirotor aircraft prior to the autonomous aerial vehicle competition. The Air Force Research Laboratory Sensors Directorate hosted the event April 28...
 
 
NASA photograph by David C. Bowman

NASA’s Langley Research Center named Vertical Flight Heritage Site

NASA photograph by David C. Bowman In a May 8ceremony, NASA’s Langley Research Center in Hampton, Virginia, was formally designated a Vertical Flight Heritage Site by the American Helicopter Society (AHS) International. F...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>