Climate satellite group defines earth's water changes

Environment News Service: Gravity Recovery and Climate Experiment, GRACE, mission operated by the Center for Space Research at the University of Texas at Austin has been recognized for outstanding contributions toward understanding the Earth through remote sensing. Aerospace Engineering Professor Byron Tapley, who directs the center and GRACE, accepted the award December 10 from the U.S. Department of the Interior and NASA "for improving scientific understanding of water changes throughout the world."

The group award was accepted by Tapley and other leaders of the GRACE team, which also includes NASA's Jet Propulsion Laboratory, Germany's space agency and Germany's National Research Center for Geosciences.

GRACE uses twin satellites to make precise measurements of gravity-field changes on Earth. Data from GRACE has established the rapid loss of ice mass in recent years from Greenland and Antarctica, and major changes in water storage in China's Yengtze River and other water sources, sometimes as a result of human use.

In addition to preparing GRACE satellite data for use by scientists internationally, the Center for Space Research engineers have improved the sensitivity of GRACE's measuring devices several times since the mission started in 2002. This spring, center staff led by Dr. Srinavas Bettadpur provided researchers with the ability to estimate mass changes with a spatial resolution of less than 200 miles.

This level of precision proved important in 2006 when GRACE data identified Greenland's accelerated ice loss. In a study published in the journal "Science," researcher Jianli Chen with the Center for Space Research and geology professor Clark Wilson and colleagues revealed that the island's ice loss occurs primarily along its southeastern edge.

Adding that ice into the North Atlantic current may lower water and wind temperatures traveling past Ireland's and Great Britain's west coasts, potentially producing chillier winters, they predict.…