Landsat mosaic of two major West Antarctic ice streams

Color shows the speed of the ice in this Landsat mosaic of two major West Antarctic ice streams. The color scale ranges from nearly zero (in blue) to 700 meter per year (in purple).

Apr 6, 2006 • In this article, glaciologist Dr. Robert Bindschadler describes his use of Landsat data to study Antarctica.

“The most impressive aspect of Antarctica is its shear enormity.  It’s larger than the United States, including Alaska.  Researchers have often felt hampered by trying to understand what the ice sheet is doing by working on its surface. It is much like trying to understand the United States when remaining in your own neighborhood. To see the major features important to Antarctic flow dynamics, I needed my eyes placed hundreds of kilometers above the ice sheet. Landsat data gave me that view.”

“Antarctica’s covering of ice is thick enough to bury most of the rugged underlying mountains. The ice is cold, but malleable enough that it moves and sometimes breaks. I have stood on many of the vast rivers of ice that drain the ice sheet, returning each snowflake back to the oceans at speeds of a few feet each day. The volume of water circulating in Antarctica is huge, enough to raise sea level globally 70 meters.”

“Landsat data have let me watch and monitor this circulation from space. We can track the motion of individual crevasses in the ice. With suitable Landsat imagery in hand, we have been able to measure in just a few days the motion of over 70,000 points on the surface using computers. The complexity of the motion field surprised us and revealed hindrances to flow within the ice stream that had not been considered previously. Landsat data continue to be a critical data source for understanding the behavior of ice sheets and how they may change sea level in the future.”

To learn more about monitoring ice sheet activity, visit the National Snow and Ice Data Center (external link).
Contributors: Robert Bindschadler, Patricia Vornberger, and Ted Scambo