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Updated: Jul 3, 2026
10:32
Image-based Lagrangian Particle Tracking in Bed-load Experiments
Published on: July 20, 2017
Comment on "Friction at the bed does not control fast glacier flow".
Brent M Minchew1, Colin R Meyer2, Samuel S Pegler3
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA. minchew@mit.edu.
Science (New York, N.Y.)
|February 9, 2019
Summary
Fast glacier sliding appears independent of basal drag, even under high stress. This finding challenges conventional physics, suggesting sliding velocity may not depend on gravitational driving stress.
Area of Science:
- Glaciology
- Earth Science
- Physics of Ice
Background:
- Basal drag is traditionally considered a primary control on glacier sliding velocity.
- The relationship between basal friction and ice flow dynamics is a key area of glaciological research.
Purpose of the Study:
- To critically evaluate the conclusion that fast glacier sliding is independent of basal drag.
- To address the fundamental physical implications of this proposed independence.
Main Methods:
- Analysis of existing glaciological data and theoretical models.
- Examination of the physical principles governing ice flow and basal interactions.
Main Results:
- The study highlights a significant physical inconsistency in the claim of basal drag independence.
- Fast glacier sliding velocity appears to be independent of basal drag, even when drag balances driving stress.
Conclusions:
- The conclusion that fast glacier sliding is independent of basal drag presents fundamental physical challenges.
- This implies that ice sliding velocity might be decoupled from stresses within the ice column, including gravitational driving stress.
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