NEAR-SURFACE FLOW IN GLACIERS OBEYING GLEN'S LAW
In determining the gravity-driven flow of a glacier or ice sheet which obeys Glen's flow law, previous methods have predicted infinite longitudinal stress at the glacier's surface. This physically unacceptable occurrence is due to a break-down in the mathematical methods used to obtain the...
| Published in: | The Quarterly Journal of Mechanics and Applied Mathematics |
|---|---|
| Main Authors: | , |
| Format: | Text |
| Language: | English |
| Published: |
Oxford University Press
1984
|
| Subjects: | |
| Online Access: | http://qjmam.oxfordjournals.org/cgi/content/short/37/2/273 https://doi.org/10.1093/qjmam/37.2.273 |
| Summary: | In determining the gravity-driven flow of a glacier or ice sheet which obeys Glen's flow law, previous methods have predicted infinite longitudinal stress at the glacier's surface. This physically unacceptable occurrence is due to a break-down in the mathematical methods used to obtain the solution. Using the method of matched asymptotic expansions, the solution valid in the near-surface region of a steady-state glacier is determined. The size of the near-surface or boundary-layer region is found to be of order δ1/n where δ = h 0 /L is the assumed small ratio of the characteristic thickness and length of the ice sheet and n is the exponent in Glen's power law. The solution is obtained for ice sheets on both a steep and gentle base slope. The stress field in the near-surface region is obtained and we find that the boundary layer does not significantly affect the surface velocities or the glacier profile. |
|---|