Watch the Wilkins ice shelf collapse in time lapse animation ? looks like ‘current’ events to me where mechanisms other than melt were discussed. It was pointed out that this photo appeared to be showing a stress crack, like the sort you’d get from a wave. Melt makes rounded irregular edges, not sharp straight line ones.
Now there’s a study from Scripps that suggests that long period waves could be a big factor.
Antarctic Ice Shelf Collapse Possibly Triggered by Ocean Waves, Scripps-led Study Finds
Extremely long waves could have initiated 2008 collapse events
Scripps Institution of Oceanography / University of California, San Diego
Depicting a cause-and-effect scenario that spans thousands of miles, a scientist at Scripps Institution of Oceanography at UC San Diego and his collaborators discovered that ocean waves originating along the Pacific coasts of North and South America impact Antarctic ice shelves and could play a role in their catastrophic collapse.
Peter Bromirski of Scripps Oceanography is the lead scientist in a new study published in the journal Geophysical Research Letters that describes how storms over the North Pacific Ocean may be transferring enough wave energy to destabilize Antarctic ice shelves. The California Department of Boating and Waterways and the National Science Foundation supported the study.
According to Bromirski, storm-driven ocean swells travel across the Pacific Ocean and break along the coastlines of North and South America, where they are transformed into very long-period ocean waves called “infragravity waves” that travel vast distances to Antarctica.
http://wattsupwiththat.com/2010/02/13/antarctic-ice-shelf-collapse-possibly-triggered-by-ocean-waves/#more-16410