Changes in West Antarctic ice stream dynamics observed with ALOS PALSAR data
Article first published online: 28 JUN 2008
Copyright 2008 by the American Geophysical Union.
Geophysical Research Letters
Volume 35, Issue 12, June 2008
How to Cite
2008), Changes in West Antarctic ice stream dynamics observed with ALOS PALSAR data, Geophys. Res. Lett., 35, L12505, doi:10.1029/2008GL033365.(
- Issue published online: 28 JUN 2008
- Article first published online: 28 JUN 2008
- Manuscript Accepted: 10 MAR 2008
- Manuscript Revised: 27 FEB 2008
- Manuscript Received: 21 JAN 2008
- climate change
 The Advanced Land Observation System (ALOS) Phased-Array Synthetic-Aperture Radar (PALSAR) is an L-band frequency (1.27 GHz) radar capable of continental-scale interferometric observations of ice sheet motion. Here, we show that PALSAR data yield excellent measurements of ice motion compared to C-band (5.6 GHz) radar data because of greater temporal coherence over snow and firn. We compare PALSAR velocities from year 2006 in Pine Island Bay, West Antarctica with those spanning years 1974 to 2007. Between 1996 and 2007, Pine Island Glacier sped up 42% and ungrounded over most of its ice plain. Smith Glacier accelerated 83% and ungrounded as well. Their largest speed up are recorded in 2007. Thwaites Glacier is not accelerating but widening with time and its eastern ice shelf doubled its speed. Total ice discharge from these glaciers increased 30% in 12 yr and the net mass loss increased 170% from 39 ± 15 Gt/yr to 105 ± 27 Gt/yr. Longer-term velocity changes suggest only a moderate loss in the 1970s. As the glaciers unground into the deeper, smoother beds inland, the mass loss from this region will grow considerably larger in years to come.