The Antarctic ice sheet covers 98 percent of the continent and contains more than half of the world's fresh water, but it doesn't just sit there like a giant ice cube.
Much of the ice is constantly flowing toward the sea under the force of its own weight. Measuring the thickness of the Antarctic ice sheet, more than three kilometers thick in some places, and mapping the topography of the underlying bedrock, helps us understand how the ice flows, and ultimately, how much it might contribute to sea level rise.
An international consortium of scientists led by the British Antarctic Survey, recently released an updated map of the bedrock that lies beneath the ice sheet.
This map, named BEDMAP2, builds on an earlier map that they released in 2001 and incorporates twenty-five million additional measurements taken over the past two decades from the ground, air, and space, including seven years of surface elevation readings from NASA's ICESat satellite and three years of laser and ice-penetrating radar data from a NASA airborne mission called Operation IceBridge. IceBridge is flown over many areas of West Antarctica, including some never before surveyed, improving the coverage and accuracy of a portion of this important data set.
BEDMAP2 gives scientists a more accurate picture of the terrain that lies beneath the ice sheet, along with ice thickness and surface elevation data. Together these measurements will improve scientists' understanding of the evolving Antarctic ice sheet and its influence on the surrounding ocean and our global climate and will enhance scientific understanding of the continent.