Numerical simulation of basal crevasses of the tidewater glacier with Galerkin least-squares finite element method

Abstract

This study employs the two-dimensional nonlinear Stokes ice sheet model and a Galerkin least-squares (GLS) finite element method to investigate iceberg calving at the terminus of tidewater glaciers. We propose an approach based on pressure and normal stress solutions to adjust the grounding line position and present effective principal stress contours and profiles for grounded and notch glaciers with basal crevasses at the grounding line. Our results indicate that the openings of these basal crevasses are significantly affected by water pressure. In addition, stress profiles in ungrounded tidewater glaciers vary from those in fully grounded tidewater glaciers, which could affect iceberg calving. We also conduct numerical experiments to analyze the effects of slip length, notch length, and surface slope and examine the effectiveness of the GLS method in numerical solutions. Our results are in agreement with prior findings in the literature that basal crevasses are significantly affected by water pressure, and stress profiles are significantly different in grounded and ungrounded tidewater glaciers.