EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Towards tackling ice-sheet ocean interaction with Finite Element Methods

Stefano Ottolenghi1 and Josefin Ahlkrona2
Stefano Ottolenghi and Josefin Ahlkrona
  • 1Stockholms universitet, Matematiska institutionen, Sweden (
  • 2Stockholms universitet, Matematiska institutionen, Sweden (

Ice sheet-ocean interaction is important to properly understand phenomena such as ice sheet melting and ocean circulation. While the long term goal of this project is to fully couple the ice and ocean in one single numerical framework, we here start by modelling the ocean. We use the full non-hydrostatic equations in order to accurately model the complex ocean dynamics near the ice sheets. As numerical method, we employ finite element methods due to their capability of representing a complex fjord geometry and locally refining the mesh in the areas which require more careful handling, and its strong mathematical foundation. This will allow to overcome classical problems such as representing a moving ice shelf in a discretized setting. We here present an example of modeled fjord circulation obtained simulating the model with the FEniCS computing platform.

How to cite: Ottolenghi, S. and Ahlkrona, J.: Towards tackling ice-sheet ocean interaction with Finite Element Methods, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11279,, 2020


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displays version 1 – uploaded on 01 May 2020
  • CC1: Comment on EGU2020-11279, Charles Pelletier, 03 May 2020

    Hi, thank you for the nice and interesting display! On the "domain mesh" slide, the ice sheet geometry is rectangular. Could you use finite elements to represent an ocean - ice shelf boundary with a slope, and have the finite elements match the slope (like it does for the bedrock bump on your slide)? Do you think this could be of use for simulating sharper, triangular-shaped ice shelf cavities, with a progressive decrease of the water column height as we approach the grounding line? If so, would there be strong constraints on the mesh resolution and/or numerical stability of the FE scheme you're using?

    • AC1: Reply to CC1, Stefano Ottolenghi, 04 May 2020

      Hi Charles, thanks for commenting! Yes, we use finite elements exactly for their flexibility with respect to the domain geometry. FE works significantly better than FD when it comes to shallow water columns and narrow/sharp regions. The current domain is quite simplified, but we intend to make it progressively similar to a realistic ocean-ice shelf. About the stability of the model, we still have to investigate that in detail, but we know there are some strategies and results that we can start from.