thumbnail

Testing the effect of water in crevasses on a physically based calving model

Annals of Glaciology

By:
, , , , and
DOI: 10.3189/2012AoG60A107

Links

Abstract

A new implementation of a calving model, using the finite-element code Elmer, is presented and used to investigate the effects of surface water within crevasses on calving rate. For this work, we use a two-dimensional flowline model of Columbia Glacier, Alaska. Using the glacier's 1993 geometry as a starting point, we apply a crevasse-depth calving criterion, which predicts calving at the location where surface crevasses cross the waterline. Crevasse depth is calculated using the Nye formulation. We find that calving rate in such a regime is highly dependent on the depth of water in surface crevasses, with a change of just a few meters in water depth causing the glacier to change from advancing at a rate of 3.5 km a-1 to retreating at a rate of 1.9 km a-1. These results highlight the potential for atmospheric warming and surface meltwater to trigger glacier retreat, but also the difficulty of modeling calving rates, as crevasse water depth is difficult to determine either by measurement in situ or surface mass-balance modelling.

Study Area

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Testing the effect of water in crevasses on a physically based calving model
Series title:
Annals of Glaciology
DOI:
10.3189/2012AoG60A107
Volume
53
Issue:
60
Year Published:
2012
Language:
English
Publisher:
International Glaciological Society
Contributing office(s):
Alaska Science Center
Description:
7 p.
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Annals of Glaciology
First page:
90
Last page:
96
Country:
United States
State:
Alaska
Other Geospatial:
Columbia Glacier