Amundsen Coast, longer view

This image shows a longer view of the Amundsen Coast from that same October 16 flight. (The downward-looking Digital Mapping System camera captured its images from an altitude of about 20,000 feet.)

The DC-8 flights were meant to supplement the information gathered since 2003 by NASA's Ice Cloud and Land Elevation Satellite, or ICESat. That satellite is down to just one operational laser (out of three), and the replacement ICESat-II won't launch until at least 2014.