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Title: Ice viscosity is more sensitive to stress than commonly assumed
Abstract Accurate representation of the viscous flow of ice is fundamental to understanding glacier dynamics and projecting sea-level rise. Ice viscosity is often described by a simple but largely untested and uncalibrated constitutive relation, Glen’s Flow Law, wherein the rate of deformation is proportional to stress raised to the power n . The value n  = 3 is commonly prescribed in ice-flow models, though observations and experiments support a range of values across stresses and temperatures found on Earth. Here, we leverage recent remotely-sensed observations of Antarctic ice shelves to show that Glen’s Flow Law approximates the viscous flow of ice with n  = 4.1 ± 0.4 in fast-flowing areas. The viscosity and flow rate of ice are therefore more sensitive to changes in stress than most ice-flow models allow. By calibrating the governing equation of ice deformation, our result is a pathway towards improving projections of future glacier change.  more » « less
Award ID(s):
1853918
PAR ID:
10417126
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Communications Earth & Environment
Volume:
3
Issue:
1
ISSN:
2662-4435
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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