Axi-symmetric ice sheet flow with evolving anisotropic fabric

• Autorzy: Staroszczyk R.
• Języki publikacji: EN

Abstrakty

EN

An axially symmetric, gravity driven, steady flow of a grounded polar ice sheet with a prescribed temperature field is considered. The ice is treated as an incompressible, non-linearly viscous, anisotropic fluid, the internal structure (fabric) of which evolves as ice descends from the free surface to depth in an ice sheet. The evolution of the ice fabric is described by an orthotropic constitutive law which relates the deviatoric stress to the strain-rate, strain, and three structure tensors based on the current (rotating) principal stretch axes. The solution of the problem is constructed as a leading-order approximation derived from asymptotic expansions in a small parameter that reflects the small ratio of stress and velocity gradients in the lateral direction of the ice sheet to those in the thickness direction. Numerical simulations of the flow problem have been carried out for various sets of rheological parameters defining the limit strength of the anisotropic fabric in ice. The results of calculations illustrate the influence of the ice anisotropy, basal melt conditions and temperature field in ice on the glacier thickness and lateral span, and on the depth profiles of the flow velocity.

Słowa kluczowe

EN

polar ice; viscosity; evolving anisotropy; orthotropy; constitutive law

• Wydawca: Polska Akademia Nauk, Wydział IV Nauk Technicznych
• Czasopismo: Bulletin of the Polish Academy of Sciences. Technical Sciences
• Rocznik: 2006
• Tom: Vol. 54, nr 4
• Strony: 419--428
• Opis fizyczny: Bibliogr. 18 poz., rys.

Twórcy

autor

Staroszczyk R.

• Institute of Hydro-Engineering, Polish Academy of Sciences, 17 Waryńskiego SL, 71-310 Szczecin, Poland,

Bibliografia

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