Lietaer, Olivier
[UCL]
Deleersnijder, Eric
[UCL]
Fichefet, Thierry
[UCL]
Vancoppenolle, Martin
[UCL]
Comblen, Richard
[UCL]
Bouillon, Sylvain
[UCL]
Legat, Vincent
[UCL]
In recent years, unstructured-mesh models have gained attention due to their
flexibility in representing complex topography and variable spatial resolution. The
Second generation Louvain-la-Neuve Ice-ocean Model (SLIM, www.climate.be/slim)
is an unstructured-mesh finite element model that is being developed at the
Université catholique de Louvain (Louvain-la-Neuve, Belgium). The ocean model
solves the shallow water equations by means of the discontinuous Galerkin finite
element method. It features a 1D river model, 2D depth averaged model and a full 3D
model.
After a general presentation of SLIM and its main applications, we will further focus
on sea-ice modeling. The sea-ice component of SLIM has representations of both
dynamic and thermodynamic sea-ice processes and includes viscous-plastic
rheology along with a complete parametrization of the atmospheric fluxes.
Unstructured meshes, with their natural ability to fit boundaries and increase locally
the mesh resolution, propose an alternative framework to capture the complex
oceanic areas formed by coasts and islands. Such an example is illustrated by the
numerous narrow straits constituting the Canadian Arctic Archipelago.
A key point of unstructured meshes is that they allow the use of mesh adaptivity. A
Lagrangian, adaptive sea ice model allowing the computational grid to move with the
ice drift is currently being developed. In order to maintain a good quality of the mesh,
the mesh has to be adapted during the simulation, involving particular mesh
adaptation techniques. This Lagrangian version of the model has several interesting
applications, such as the dynamical mesh refinement along any region of interest
(e.g., the ice edge), buoys tracking, or the inclusion of material properties in the
rheology.
Among these applications, the ice age constitutes both an interesting diagnostic tool
and parameter for determining the ice physical properties (albedo, strength, salinity,
...). There are basically two ways of modeling the ice age: as a bidimensional tracer
or as a vertical tracer, but different definitions exist and lead to different
interpretations.
In this work, we first present the equation of evolution of the age in an onedimensional
ice layer. This equation is applied to a stand-alone thermodynamic sea
ice model and its numerical resolution is compared to the integration of the ice age
thanks to Lagrangian particles in the vertical direction.
Preliminary results of a simulation of the Arctic Basin are finally shown where the
Lagrangian model is used to transport the vertical structure of ice age
Bibliographic reference |
Lietaer, Olivier ; Deleersnijder, Eric ; Fichefet, Thierry ; Vancoppenolle, Martin ; Comblen, Richard ; et. al. SLIM: A finite-element, unstructured-mesh model forsimulating thermodynamic and dynamic sea-ice processes. : Application: the theory of the sea-ice age.Belgian IPY Symposium. The Contribution of Belgian Research to the Achievements of the International Polar Year 2007-2009, Koninklijke Vlaamse Academie van Belgie voor Wetenschappen en Kunsten, pp. 24-26 (Brussels, 26/05/2010). |
Permanent URL |
http://hdl.handle.net/2078.1/71117 |