Spatial Variability in Surface Elevation Changes of Central-West Greenland Outlet Glaciers

Tuesday, 16 December 2014
Denis Felikson1, Ginny A Catania1, Kurt Henrik Kjaer2, Niels J Korsgaard3, Leigh A Stearns4, Jonathan D Nash5, Emily Shroyer5, Dave Sutherland6 and Ryan T Walker7, (1)University of Texas at Austin, Austin, TX, United States, (2)Natural History Museum of Denmark, Copenhagen, Denmark, (3)University of Copenhagen, Copenhagen, Denmark, (4)University of Kansas, Department of Geology, Lawrence, KS, United States, (5)Oregon State Univ, Corvallis, OR, United States, (6)University of Oregon, Eugene, OR, United States, (7)University of Maryland, Greenbelt, MD, United States
The mass balance of the Greenland ice sheet (GrIS) is, in part, governed by the dynamics of ocean-terminating glaciers. GRACE data reveal that along the central-west coast of the GrIS, overall ice loss has been accelerating since 2007. However, we do not know the physical processes controlling the loss here, and the changes observed are not uniform in this region; several glaciers have gone through periods of slow-down in the recent past.

To address these uncertainties, we have performed ~30-year DEM differences of outlet glaciers in the region. Present-day DEMs have been created from WorldView-1 and -2 (WV) stereo imagery acquired in 2012 and 2013 using the AMES Stereo Pipeline. A 1985 DEM was created from a Greenland aerial photo survey. The DEM differences between the present-day WV DEMs and the 1985 aerial photo DEM show clearly that spatial variability in the surface elevation and terminus position changes of the glaciers in the region has been ongoing for the last ~30 years. We examine this variability in the context of ocean temperature and surface mass balance estimates to yield further insight into the external controls on these glaciers.