The Grand Canyon of Greenland
"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 (750 kilometers) long, making it longer than the Grand Canyon. In some places, it is as deep as 2,600 feet (800 meters), 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...
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."
(I do wish people would not say "Artic" Ocean.)
At the eighth second of the video there is also an interesting fjord shape on the West!
ReplyDeleteAgreed. That one would correspond to the Ilulissat Icefjord, which has been declared a UNESCO World Heritage site:
Deletehttp://whc.unesco.org/en/list/1149/