28 citations · 49 across the 8 of their papers we have counts for
9 papers
A numerical stabilization scheme for the shallow shelf approximation
Tilda Westling Dolling, A. Clara J. Henry, Josefin Ahlkrona
We present the Thickness Stabilization Scheme (TSS), a numerical stabilization scheme suitable for the Shallow Shelf Approximation (SSA), one of the most widely-used models for lar…
Free-surface Stokes problem: stability estimates and time-step improvements
Igor Tominec, Lukas Lundgren, André Löfgren +1
Accurate simulations of ice sheet dynamics, mantle convection, lava flow, and other highly viscous free-surface flows involve solving the coupled Stokes/free-surface equations. In…
A potential energy conserving finite element method for turbulent variable density flow: application to glacier-fjord circulation
Lukas Lundgren, Christian Helanow, Jonathan Wiskandt +2
We introduce a continuous Galerkin finite element discretization of the non-hydrostatic Boussinesq approximation of the Navier-Stokes equations, suitable for various applications s…
Well-posedness of the Stokes problem under modified pressure Dirichlet boundary conditions
Igor Tominec, Josefin Ahlkrona, Malte Braack
This paper shows that the Stokes problem is well-posed when velocity and pressure simultaneously vanish on the domain boundary. This result is achieved by extending Nečas' inequali…
Weak form Shallow Ice Approximation models with an improved time step restriction
Igor Tominec, Josefin Ahlkrona
The Shallow Ice Approximation (SIA) model on strong form is commonly used for inferring the flow dynamics of grounded ice sheets. The solution to the SIA model is a closed-form exp…
Theoretical results on a block preconditioner used in ice-sheet modeling: eigenvalue bounds for singular power-law fluids
Christian Helanow, Josefin Ahlkrona
The properties of a block preconditioner that has been successfully used in finite element simulations of large scale ice-sheet flow is examined. The type of preconditioner, based…
Increasing stable time-step sizes of the free-surface problem arising in ice-sheet simulations
André Löfgren, Josefin Ahlkrona, Christian Helanow
Numerical models for predicting future ice-mass loss of the Antarctic and Greenland ice sheet requires accurately representing their dynamics. Unfortunately, ice-sheet models suffe…
Galerkin Least-Squares Stabilization in Ice Sheet Modeling - Accuracy, Robustness, and Comparison to other Techniques
Christian Helanow, Josefin Ahlkrona
We investigate the accuracy and robustness of one of the most common methods used in glaciology for the discretization of the -Stokes equations: equal order finite el…
Dynamically coupling the non-linear Stokes equations with the Shallow Ice Approximation in glaciology: Description and first applications of the ISCAL method
Josefin Ahlkrona, Per Lötstedt, Nina Kirchner +1
We propose and implement a new method, called the Ice Sheet Coupled Approximation Levels (ISCAL) method, for simulation of ice sheet flow in large domains under long time-intervals…