Variations in Ice Speed at a Rapidly Retreating Glacier: Yakutat Glacier, Alaska
Abstract
The Yakutat Glacier, a lacustrine glacier in southeast Alaska, has undergone dramatic thinning and terminus retreat over the past decade. We present a time series of surface ice velocities from 2011-present derived from a pixel tracking technique using TerraSAR-X synthetic aperture radar data and examine how observed variations in ice speed are related to seasonal fluctuations and longer-term changes in ice dynamics.
The eastern branch of the glacier has gaps in the ice speed maps due to low coherence in the SAR data and overall displays lower speeds than the western branch, which shows considerable variability in surface ice speeds. Seasonally, the western branch exhibits patterns similar to several other glaciers in coastal Alaska: peaks in speed in winter and late spring, lower speeds in late winter/early spring and summer, and an increase in speeds in the fall. Interannually, the western branch shows markedly higher winter speeds in 2013 than in subsequent years. In 2016, there is overall less variability in speed than in previous years and winter and spring speeds are lower than those observed in 2015.- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.C11C1142E
- Keywords:
-
- 0758 Remote sensing;
- CRYOSPHEREDE: 0762 Mass balance;
- CRYOSPHEREDE: 0774 Dynamics;
- CRYOSPHEREDE: 0776 Glaciology;
- CRYOSPHERE