Modelling the small-scale deposition of snow onto structured Arctic sea ice using OpenFOAM

• Main Author: Hames, Océane
• Format: Text
• Language: unknown
• Published: 2021
• Subjects: Arctic; Sea ice
• Online Access: http://infoscience.epfl.ch/record/285105; https://infoscience.epfl.ch/record/285105/files/HAMES_PDM%20PRINTEMPS%202020.pdf

The remoteness and extreme conditions of the Arctic make it a very difficult environment to investigate. In these regions, the wind has a substantial effect and redistributes a large part of the snow which complicates precipitation estimates. Moreover, the snow mass balance on sea ice is still poorly understood notably due to the complex structure of its surface. Quantitatively assessing the snow distribution on sea ice and its connection to the sea ice surface features is an important step to remove these uncertainties. In this thesis, we implemented a physics-based snow saltation model in the open source fluid dynamics software OpenFOAM. After validation against real and numerical data, we used the model to simulate snow deposition on a small piece of MOSAiC sea ice with a complicated structure of pressure ridges. The results demonstrate that a large fraction of snow accumulates in their vicinity, which compares favorably against terrestrial laser scans. The accurate modelling of snow distribution on sea ice should help to better constrain precipitation estimates and more generally the projections of future sea ice mass balance changes.