Vast rivers of ice flow from Antarctica’s inner regions out to the coasts, as shown in an animated map released by NASA.
The map offers glaciologists and climate change researchers a full view of the speed and direction of moving ice on the continent, and reveals several new features.
“This is like seeing a map of all the oceans’ currents for the first time,” said Eric Rignot of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and the University of California, Irvine in a press release. “It’s a game changer for glaciology.”
To compile the map, Rignot and his colleagues used 3,000 different orbital tracks from polar-orbiting satellites. With billions of data points, they corrected for the effects of cloud cover, solar glare and land features to see where certain “fingerprints” several meters below the ice surface were moved. Some travel as much as 800 feet in a year.
In addition to uncovering a new ridge that runs east to west across the continent, the map points to a new explanation of how ice migrates: by slipping along the land it rests upon. Some glaciologists had previously assumed that deep ice degraded after being crushed by ice above.
“That’s critical knowledge for predicting future sea level rise,” said Thomas Wagner, NASA’s cryospheric program scientist in Washington, in NASA’s release. “It means that if we lose ice at the coasts from the warming ocean, we open the tap to massive amounts of ice in the interior.”
Image: NASA
See Also:
Antarctic Ice-Core Research Requires Logistical High-Wire Act
Global Warming Protects Antarctic Sea Ice — But Not For Long
Citation: “Ice Flow of the Antarctic Ice Sheet.” By Eric Rignot, Jeremie Mouginot and Bernd Scheuchl. Science Express. August 18, 2011.
