Using technology similar to an MRI to scan the floor of the North Sea, scientists have revealed hidden landscapes created by ancient ice sheets.
The experts found “tunnel valleys” buried hundreds of feet below the bottom of the sea. These are the remnants of massive rivers formed as the ice started to melt in response to warming ambient temperatures.
Study lead author James Kirkham is a researcher at the Scott Polar Research Institute and the British Antarctic Survey.
“The origin of these channels was unresolved for over a century. This discovery will help us better understand the ongoing retreat of present-day glaciers in Antarctica and Greenland,” explained Kirkham.
“In the way that we can leave footprints in the sand, glaciers leave an imprint on the land upon which they flow. Our new cutting edge data gives us important markers of deglaciation. ”
The technology used sound waves to create detailed images of a lost landscape formed by melting ice. It may give scientists a window into our own future warming planet through the lens of the past.
“Although we have known about the huge glacial channels in the North Sea for some time, this is the first time we have imaged fine-scale landforms within them. These delicate features tell us about how water moved through the channels (beneath the ice) and even how ice simply stagnated and melted away,” said study co-author Dr. Kelly Hogan.
“It is very difficult to observe what goes on underneath our large ice sheets today, particularly how moving water and sediment is affecting ice flow and we know that these are important controls on ice behavior. As a result, using these ancient channels to understand how ice will respond to changing conditions in a warming climate is extremely relevant and timely.”
The study is published in the journal Geology.
—By Zach Fitzner, Earth.com Staff Writer