CU-Boulder study shows global glaciers, ice caps, shedding billions of tons of mass annually

Changes in ice thickness (in centimeters per year) during 2003-2010 as measured by NASA's Gravity Recovery and Climate Experiment (GRACE) satellites, averaged over each of the world's ice caps and glacier systems outside of Greenland and Antarctica. Blue represents ice mass loss, while red represents ice mass gain. Image credit: NASA/JPL-Caltech/University of Colorado.


Earth's glaciers and ice caps outside of the regions of Greenland and Antarctica are shedding roughly 150 billion tons of ice annually, according to a new study led by the University of Colorado Boulder.

The research effort is the first comprehensive satellite study of the contribution of the world's melting glaciers and ice caps to global sea level rise and indicates they are adding roughly 0.4 millimeters annually, said CU-Boulder physics Professor John Wahr, who helped lead the study. The measurements are important because the melting of the world's glaciers and ice caps, along with Greenland and Antarctica, pose the greatest threat to sea level increases in the future, Wahr said.

The researchers used satellite measurements taken with the Gravity Recovery and Climate Experiment, or GRACE, a joint effort of NASA and Germany, to calculate that the world's glaciers and ice caps had lost about 148 billion tons, or about 39 cubic miles of ice annually from 2003 to 2010. The total does not count the mass from individual glacier and ice caps on the fringes of the Greenland and Antarctic ice sheets - roughly an additional 80 billion tons.

"This is the first time anyone has looked at all of the mass loss from all of Earth's glaciers and ice caps with GRACE," said Wahr. "The Earth is losing an incredible amount of ice to the oceans annually, and these new results will help us answer important questions in terms of both sea rise and how the planet's cold regions are responding to global change."
Read article here