Simulating sea-ice deformation in viscous-plastic sea-ice models with CD-grids ...

• Main Authors: Mehlmann, C., Capodaglio, G., Danilov, S.
• Format: Report
• Language: unknown
• Published: arXiv 2023
• Subjects: Numerical Analysis math.NA; FOS Mathematics; Arctic; Sea ice
• Online Access: https://dx.doi.org/10.48550/arxiv.2304.08344; https://arxiv.org/abs/2304.08344

Linear Kinematic Features (LKFs) are found everywhere in the Arctic sea-ice cover. They are strongly localized deformations often associated with the formation of leads and pressure ridges. Viscous-plastic sea-ice models start to produce LKFs at high spatial grid resolution, typically with a grid spacing below 5 km. A recent study showed that the placement of the variables on the grid plays an important role for the number of simulated LKFs. The study found that a nonconforming finite element discretization with a CD-grid placement (CD1) resolves more LKFs per degree of freedom compared to more common A,B and C-grids. A new CD-grid formulation (CD2) has just been proposed based on a conforming subgrid discretization. To analyze the resolution properties of the new CD2 approach we evaluate runs from different models (e.g FESOM, MPAS) on a benchmark problem using quadrilateral, hexagonal and triangular meshes. We found that the CD1 setup simulates more deformation structure than the CD2 approximation. This ...