Anisotropic Ice Flow
Anisotropy. A material is anisotropic if it has a response that differs according to the direction of the loading.
Ice anisotropy. In this article, we focus on the viscous part of the ice deformation. Elastic response of ice is also anisotropic but much less pronounced than its viscous part.
The size of an ice crystal varies from few millimeters to few tens of centimeters, whereas the typical size of a glacier or an ice sheet is few kilometers to thousands of kilometers. The strong viscous anisotropy of the ice crystal and the way the crystals are orientated influence the flow of glaciers and ice sheets. This article explains how these very different scales are related and coupled, leading to special features that can only be explained by an anisotropic behavior.
Anisotropy of the ice crystal
Terrestrial ice presents a hexagonal symmetry that induces a strong viscous anisotropic behavior. The principal mechanism responsible for the crystal deformation is the...
- Durand, G., Gillet-Chaulet, F., Svensson, A., Gagliardini, O., Kipfstuhl, S., Meyssonnier, J., Parrenin, F., Duval, P., and Dahl-Jensen, D., 2007. Change of the ice rheology with climatic transitions – implication on ice flow modelling and dating of the EPICA Dome C core. Climate of the Past, 3, 155–167.Google Scholar
- Gagliardini O., Gillet-Chaulet, F., and Montagnat, M., 2009. A review of anisotropic polar ice models: from crystal to ice-sheet flow models. In “Physics of Ice Core Records II.” Supplement Issue of Low Temperature Science, 68, December 2009.Google Scholar
- Lliboutry, L., and Duval, P., 1985. Various isotropic and anisotropic ices found in glacier and polar ice caps and their corresponding rheologies. Annales Geophysicae, 3(2), 207–224.Google Scholar
- Paterson, W. S. B., 1991. Why ice-age is sometimes soft. Cold Regions Science and Technology, 20, 75–98.Google Scholar
- Placidi, L., Hutter, K., and Faria, S., 2006. A critical review of the mechanics of polycrystalline polar ice. GAMM-Mitt, 29(1), 77–114.Google Scholar
- Thorsteinsson, T., and Waddington, D., 2002. Folding in strongly anisotropic layers near ice-sheet centers. Annals of Glaciology, 35, 480–486.Google Scholar