Thinning and slowdown of Greenland's Mittivakkat Gletscher
S. H. Mernild1, N. T. Knudsen2, M. J. Hoffman3, J. C. Yde4, W. H. Lipscomb2, E. Hanna5, J. K. Malmros6, and R. S. Fausto71Climate, Ocean, and Sea Ice Modeling Group, Computational Physics and Methods, Los Alamos National Laboratory, New Mexico, USA 2Department of Geoscience, Aarhus University, Aarhus, Denmark 3Climate, Ocean, and Sea Ice Modeling Group, Fluid Dynamics and Solid Mechanics, Los Alamos National Laboratory, New Mexico, USA 4Sogn og Fjordane University College, Sogndal, Norway 5Department of Geography, University of Sheffield, UK 6Centro de Estudios Científicos, Valdivia, Chile 7Geological Survey of Denmark and Greenland, Denmark
Received: 07 Sep 2012 – Accepted for review: 26 Sep 2012 – Discussion started: 12 Oct 2012
Abstract. Here, we document changes for the Mittivakkat Gletscher, the glacier in Greenland (disconnected to the Greenland Ice Sheet, GrIS) having the longest observed mass balance and surface velocity time series (since 1995). Between 1986 and 2011, this glacier decreased by 15% in mean ice thickness and 30% in volume. We attribute these changes to summer warming and less winter snowfall. The vertical strain was able to compensate about 60% of the elevation change due to surface mass balance (SMB) in the lower part, and about 25% in the upper part. The annual mean ice surface velocity decreased by 30%, likely as a dynamic effect of ice thinning. Mittivakkat Gletscher summer surface velocities were on average 50–60% above winter background values, and up to 160% higher during peak velocity events.
Mernild, S. H., Knudsen, N. T., Hoffman, M. J., Yde, J. C., Lipscomb, W. H., Hanna, E., Malmros, J. K., and Fausto, R. S.: Thinning and slowdown of Greenland's Mittivakkat Gletscher, The Cryosphere Discuss., 6, 4387-4415, doi:10.5194/tcd-6-4387-2012, 2012.