A two layer model for wave dissipation in sea ice. (July 2019)

• Record Type: Journal Article
• Authors: Sutherland, Graig; Rabault, Jean; Christensen, Kai H.; Jensen, Atle
• Is Part Of: Applied ocean research. Volume 88(2019)
• Page Start: 111
• Page End: 118
• Publication Date: 2019-07
• Subjects: Waves -- Sea ice -- Wave dissipation -- Wave-ice interaction; Ocean engineering -- Periodicals; 620.416205
• DOI: 10.1016/j.apor.2019.03.023
• Languages: English
• ISSNs: 0141-1187

Abstract

Abstract: Sea ice is highly complex due to the inhomogeneity of the physical properties (e.g. temperature and salinity) as well as the permeability and mixture of water and a matrix of sea ice and/or sea ice crystals. Such complexity has proven itself to be difficult to parameterize in operational wave models. Instead, we assume that there exists a self-similarity scaling law which captures the first order properties. Using dimensional analysis, an equation for the kinematic viscosity is derived, which is proportional to the wave frequency and the ice thickness squared. In addition, the model allows for a two-layer structure where the oscillating pressure gradient due to wave propagation only exists in a fraction of the total ice thickness. These two assumptions lead to a spatial dissipation rate that is a function of ice thickness and wavenumber. The derived dissipation rate compares favourably with available field and laboratory observations.