First complete map of the speed and direction of ice flow in Antarctica, derived from radar interferometric data from the Japan Aerospace Exploration Agency's ALOS PALSAR, the European Space Agency's Envisat ASAR and ERS-1/2, and the Canadian Space Agency's RADARSAT-2 spacecraft. The color-coded satellite data are overlaid on a mosaic of Antarctica created with data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA's Terra spacecraft. Pixel spacing is 984 feet (300 meters). The thick black lines delineate major ice divides. Subglacial lakes in Antarctica's interior are also outlined in black. Thick black lines along the coast indicate ice sheet grounding lines. (NASA/Caltech-JPL)
PASADENA, Calif. - NASA-funded scientists have created the first complete map of Antartic ice flow using the combined data from a group of international satellites. The map will be useful in tracking sea-level changes caused by climate change, NASA says.
The combined map revealed several previously unknown facts. Included are ice flows from the continent's interior, a new ridge splitting the continent and the finding that ice flows by sliding on top of the land it rests on. "That's critical knowledge for predicting future sea level rise," said Thomas Wagner, NASA's cryospheric program scientist in Washington. "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."
"This is like seeing a map of all the oceans' currents for the first time. It's a game changer for glaciology," said Eric Rignot of NASA's Jet Propulsion Laboratory in Pasadena, Calif., and the University of California (UC), Irvine. Rignot is lead author of a paper about the ice flow published online Thursday in Science Express. "We are seeing amazing flows from the heart of the continent that had never been described before."
A video animation of the new Antarctic map is below.