Document Type

Other

Publication Title

Journal of Geophysical Research-Solid Earth

Publication Date

2009

Publication Number

B04499

Volume Number

114

Abstract/ Summary

A geometrical force balance that links stresses to ice bed coupling along a flow band of an ice sheet was developed in 1988 for longitudinal tension in ice streams and published 4 years later. It remains a work in progress. Now gravitational forces balanced by forces producing tensile, compressive, basal shear, and side shear stresses are all linked to ice bed coupling by the floating fraction phi of ice that produces the concave surface of ice streams. These lead inexorably to a simple formula showing how phi varies along these flow bands where surface and bed topography are known: phi = h(O)/h(I) with h(O) being ice thickness h(I) at x = 0 for x horizontal and positive upslope from grounded ice margins. This captures the basic fact in glaciology: the height of ice depends on how strongly ice couples to the bed. It shows how far a high convex ice sheet (phi = 0) has gone in collapsing into a low flat ice shelf (phi = 1). Here phi captures ice bed coupling under an ice stream and h(O) captures ice bed coupling beyond ice streams.

Citation/Publisher Attribution

Hughes, T, 2009, Variations of Ice Bed Coupling Beneath and Beyond Ice Streams: The Force Balance: Journal of Geophysical Research-Solid Earth, v. 114, B04499. To view the published open abstract, go to http://dx.doi.org and enter the DOI.

Publisher Statement

© Copyright 2009 American Geophysical Union

DOI

10.1029/2009JB006426

Version

publisher's version of the published document

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