Combining damage and fracture mechanics to model calving
Calving of icebergs is a major negative component of polar ice-sheet mass balance. Here we present a new calving model relying on both continuum damage mechanics and linear elastic fracture mechanics. This combination accounts for both the slow sub-critical surface crevassing and the rapid propagati...
| Published in: | The Cryosphere |
|---|---|
| Main Authors: | , , , |
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2014-11-01
|
| Subjects: | |
| Online Access: | http://www.the-cryosphere.net/8/2101/2014/tc-8-2101-2014.pdf |
| Summary: | Calving of icebergs is a major negative component of polar ice-sheet mass
balance. Here we present a new calving model relying on both continuum damage
mechanics and linear elastic fracture mechanics. This combination accounts
for both the slow sub-critical surface crevassing and the rapid propagation
of crevasses when calving occurs. First, damage to the ice occurs over long
timescales and enhances the viscous flow of ice. Then brittle fractures
propagate downward, at very short timescales, when the ice body is considered
as an elastic medium. The model was calibrated on Helheim Glacier, Southeast
Greenland, a well-monitored glacier with fast-flowing outlet. This made it possible
to identify sets of model parameters to enable a consistent response of the
model and to produce a dynamic equilibrium in agreement with the observed
stable position of the Helheim ice front between 1930 and today. |
|---|---|
| ISSN: | 1994-0416 1994-0424 |