Calving Geometry of Thwaites Glacier Linked to Semi-brittle Ice Dynamics
Abstract
In the coming decades the linkage between ice dynamics, basal melt, and calving will play a central role in the flow of Thwaites Glacier, which has undergone vast and recent retreat. We explore this connection using a 3D, transient, thermomechanical ice flow model under different basal melt scenarios. Our use of a semi-brittle ice rheology enables the time-dependent development and tracking of surface and basal crevasses that determine the calving rate at this location. With the use of adaptive re-meshing, we are able to simulate the glacier's retreat response to different boundary forcings. We show that the resulting characteristic pinch-and-swell model geometries in the floating tongue compare well with airborne radar data acquired across the grounding line and floating tongue of Thwaites Glacier. These geometric features may be reproduced using this semi-brittle rheology, and further, are linked directly to the calving rate of Thwaites Glacier (and others). The use of semi-brittle rheology on decadal time scales may help provide constraints on the near-term future behavior of glaciers vulnerable to ocean-induced retreat, as this rheology targets the complex interaction of ice failure, basal melt, and flow.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.P31A2085L
- Keywords:
-
- 0774 Dynamics;
- CRYOSPHEREDE: 4540 Ice mechanics and air/sea/ice exchange processes;
- OCEANOGRAPHY: PHYSICALDE: 5422 Ices;
- PLANETARY SCIENCES: SOLID SURFACE PLANETSDE: 8045 Role of fluids;
- STRUCTURAL GEOLOGY