16 Jun 2014:
Skyscraper-Size Ice Structures
Discovered at Base of Greenland Ice Sheet
Click to Enlarge
Bell et al., 2014
Massive structures at base of Greenland ice sheet.
Melting and refreezing at the base of the Greenland ice sheet has created massive, complex structures the height of skyscrapers and the width of Manhattan, according to
research published in Nature Geoscience
. The hidden formations more than a mile below the surface stand in stark contrast to the nearly flat, smooth exterior of the ice sheet and may accelerate its flow toward the sea, researchers say. Scientists had previously interpreted the irregular topography at the base of the ice as hills or mountains, but ice-penetrating radar revealed that the structures were made of ice rather than rock. Scientists from Columbia University explained that as meltwater at the bottom refreezes over hundreds or thousands of years, it radiates heat into the surrounding ice sheet, making it pick up its pace as the ice becomes softer and flows more easily. Greenland's glaciers appear to be moving more rapidly toward the sea as climate warms, but it remains unclear how the refreezing process will influence this trend, the researchers said. "We see more of these features where the ice sheet starts to go fast," said the study's lead author. "We think the refreezing process uplifts, distorts and warms the ice above, making it softer and easier to flow."
Yale Environment 360 is
a publication of the
Yale School of Forestry
& Environmental Studies
Yale Environment 360
articles are now available in Spanish and Portuguese on Universia
, the online educational network. Visit the site.
Business & Innovation
Policy & Politics
Pollution & Health
Science & Technology
Antarctica and the Arctic
Central & South America
Tribal people and ranchers join together to stop a project that would haul coal across their Montana land. Watch the video.
is now available for mobile devices at e360.yale.edu/mobile
A, aerial view of why Europe’s per capita carbon emissions are less than 50 percent of those in the U.S. View the photos.
The 2015 Yale e360 Video Contest winner documents a Northeastern town's bitter battle over a wind farm. Watch the video.
video series looks at the staggering amount of food wasted in the U.S. – a problem with major human and environmental costs. Watch the video.
video goes onto the front lines with Colorado firefighters confronting deadly blazes fueled by a hotter, drier climate. Watch the video.
A three-part series Tainted Harvest
looks at the soil pollution crisis in China, the threat it poses to the food supply, and the complexity of any cleanup. Read the series.