Iceberg calving during transition from grounded to floating ice: Columbia Glacier, Alaska
Article first published online: 7 AUG 2010
Copyright 2010 by the American Geophysical Union.
Geophysical Research Letters
Volume 37, Issue 15, August 2010
How to Cite
2010), Iceberg calving during transition from grounded to floating ice: Columbia Glacier, Alaska, Geophys. Res. Lett., 37, L15501, doi:10.1029/2010GL043201., , , , , and (
- Issue published online: 7 AUG 2010
- Article first published online: 7 AUG 2010
- Manuscript Accepted: 20 MAY 2010
- Manuscript Revised: 7 MAY 2010
- Manuscript Received: 16 MAR 2010
 The terminus of Columbia Glacier, Alaska, unexpectedly became ungrounded in 2007 during its prolonged retreat. Visual observations showed that calving changed from a steady release of low-volume bergs, to episodic flow-perpendicular rifting, propagation, and release of very large icebergs - a style reminiscent of calving from ice shelves. Here, we compare passive seismic and photographic observations through this transition to examine changes in calving. Mechanical changes accompany the visible changes in calving style post flotation: generation of seismic energy during calving is substantially reduced. We propose this is partly due to changes in source processes.