English: The topography of the bedrock under the Antarctic ice sheet is critical to understanding the dynamic motion of the ice sheet, its thickness and its influence on the surrounding ocean and global climate. In 2001, the British Antarctic Survey (BAS) released a map of the bed under the Antarctic Ice Sheet and the seabed extending out on to the continental shelf derived from data collected by an international consortium of scientists over the prior fifty years. The resulting dataset was called BEDMAP (or BEDMAP1).

In 2013, BAS released an update of the topographic dataset called BEDMAP2 that incorporates twenty-five million measurements taken over the past two decades from the ground, air and space. This animation compares the new BEDMAP2 dataset to the original BEDMAP1 dataset

Source http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=4060