title: Rapid changes in ice discharge from Greenland outlet glaciers.
abstract: Using satellite-derived surface elevation and velocity data, we found major short-term variations in recent ice discharge and mass loss at two of Greenland's largest outlet glaciers. Their combined rate of mass loss doubled in less than a year in 2004 and then decreased in 2006 to near the previous rates, likely as a result of fast re-equilibration of calving-front geometry after retreat. Total mass loss is a fraction of concurrent gravity-derived estimates, pointing to an alternative source of loss and the need for high-resolution observations of outlet dynamics and glacier geometry for sea-level rise predictions.
authors.affiliation: Polar Science Center, Applied Physics Lab, University of Washington, 1013 Northeast 40th Street, Seattle, WA 98105-6698, USA. ihowat@apl.washington.edu
authors.forename: Ian M
authors.initials: IM
authors.lastname: Howat
authors.forename: Ian
authors.initials: I
authors.lastname: Joughin
authors.forename: Ted A
authors.initials: TA
authors.lastname: Scambos