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Journal of Glaciology

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Abstract/ Summary

The floating terminal of Jakobshavn Isbr ae, the fastest Greenland ice stream, has disintegrated since 2002, resulting in a doubling of ice velocity and rapidly lowering inland ice elevations. Conditions prior to disintegration were modeled using control theory in a plane-stress solution, and the Missoula model of ice-shelf flow. Both approaches pointed to a mechanism that inhibits ice flow and that is not captured by either approach. Jamming of flow, an inherent property of granular materials passing through a constriction (Jakobshavn Isfjord), is postulated as the mechanism. Rapid disintegration of heavily crevassed floating ice accompanies break-up of the ice jam.

Citation/Publisher Attribution

Johnson, JV, Prescott, PR, and Hughes, TJ, 2004, Ice Dynamics Preceding Catastrophic Disintegration of the Floating Part of Jakobshavn Isbrie, Greenland: Journal of Glaciology, v. 50, p. 492-504. Available on publisher's site at:

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© Copyright 2004 by the International Glaciological Society




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