Dynamics at the Ice/ocean Interface
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Among the least understood components affecting global climate, polar ice coverage is near the top of the list. From sea level rise to surface reflectivity, glaciers and sea ice provoke a strong, nonlinear response in the surface energy balance of our planet, and are currently undergoing a dramatic transition. Stoic ice sheets that have covered Antarctica and Greenland for tens of thousands of years are thinning and flowing towards the ocean at an unprecedented rate, as evidenced by retreating glaciers, increased ice calving, and glacial earthquakes. For many years glaciologists have thought of ice as a slow-moving, viscoplastic flow driven by gravity. However, catastrophic events such as the collapse of massive ice shelves in a matter of weeks (Larsen B, 2002; Wilkins, 2008) and the capsize of icebergs large enough to cause a magnitude 5 earthquake have challenged this predominant view.
We have designed a series of lab experiments to model icebergs at the glacier/ocean interface. After a large iceberg calves from the front of a glacier terminus, it can be gravitationally unstable and will capsize, releasing many kilotons of TNT worth of energy. This energy is mostly redistributed through turbulent mixing in the water (left), and ultimately dissipated by viscosity. Our experiments focus on many aspects of such "dynamic mass losses", including tracking the flow during a model capsize event and measuring the forces involved in a "glacial earthquake".
Laboratory Investigations of Iceberg-Capsize dynamics, Energy Dissipation and Tsunamigenesis
J. C. Burton, J. M. Amundson, D. S. Abbot, A. Boghosian, L. Mac. Cathles, S. Correa-Legisos, K. N. Darnell, N. Guttenberg, D. M. Holland, and D. R. MacAyeal. JGR - Earth Surface 117, F01007 (2012).
We have designed a series of lab experiments to model icebergs at the glacier/ocean interface. After a large iceberg calves from the front of a glacier terminus, it can be gravitationally unstable and will capsize, releasing many kilotons of TNT worth of energy. This energy is mostly redistributed through turbulent mixing in the water (left), and ultimately dissipated by viscosity. Our experiments focus on many aspects of such "dynamic mass losses", including tracking the flow during a model capsize event and measuring the forces involved in a "glacial earthquake".
Laboratory Investigations of Iceberg-Capsize dynamics, Energy Dissipation and Tsunamigenesis
J. C. Burton, J. M. Amundson, D. S. Abbot, A. Boghosian, L. Mac. Cathles, S. Correa-Legisos, K. N. Darnell, N. Guttenberg, D. M. Holland, and D. R. MacAyeal. JGR - Earth Surface 117, F01007 (2012).