Finite element formulation of viscous sea ice model

• Main Author: Reddy, Satti Vijaya Bhaskara
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 1977
• Subjects: Arctic; Belle Isle; Strait of Belle Isle; Arctic Basin; Sea ice
• Online Access: https://research.library.mun.ca/5263/; https://research.library.mun.ca/5263/1/Reddy_SattiVijayaBhaskara.pdf; https://research.library.mun.ca/5263/2/Reddy_SattiVijayaBhaskara.pdf

The steady drift of sea ice in the Arctic Basin has been calculated by using the Finite Element Method, assuming that the ice is a viscous material. The Arctic Basin is discretized into 9 x 13 square elements of size 250 km by 250 km. The constitutive relations proposed by Glen 1970 have been used in the modeling. The momentum and continuity equations are solved for the ice velocity due to wind stress ocean current and ocean tilt. The drift has been calculated for four seasons in a span of two years by using proper viscosities in summer and winter. The vector addition of ice velocities due to wind, ocean current and tilt are plotted as combined velocities for all four seasons Summer 1, Winter 1, Summer 2 and Winter 2. -- The results of the Finite Element Method of analysis are compared with that of the Fourier Transform Method (Hibler, 1976) and it is found that the results obtained by both methods agree with each other in the middle of the Basin. A comparison between skip and no slip boundary condition is also presented. Boundary elements are used and an iterative procedure is followed to incorporate the nonlinear boundary conditions. -- A non-steady drift of pack ice in the Strait of Belle Isle, which moves back and forth due to tidal streams and current have been calculated by the finite element method formulation. It is observed that the pack ice velocities are harmonic as are the water velocities but with a time lag which depends upon viscosity parameters of ice. -- Various velocity fields have been plotted and all patterns of calculated velocities are observed to be realistic.