Author(s): F. Nelli; D. M. Skene; L. G. Bennetts; M. H. Meylan; J. H. Lee; J. P. Monty; A. Toffoli
Linked Author(s): Joseph Hun-Wei Lee
Keywords: No Keywords
Abstract: The marginal ice zone (MIZ) is the highly dynamic region of the partially ice covered ocean that separates the open ocean from the quasi-continuous pack ice. It is 10s to 100s of kilometres wide, depending on the season and location. Ocean surface waves are present in the MIZ. They contribute to its dynamic nature both indirectly by breaking up larger floes to leave a more mobile ice cover, and directly by setting the smaller floes in motion. At the same time, the ice cover attenuates wave energy, thus limiting the distance over which they impact the ice. Therefore, models of wave attenuation underpin MIZ models. At present, attenuation models are based on linear wave scattering theory and the use of thin plates to model the floes. However, Toffoli et al (2015, Geophys. Res. Lett., 42) use laboratory experimental measurements of wave attenuation by a single plate to show that these models underestimate the attenuation for moderate wave steepnesses or larger. Here, we extend Toffoli et al’s investigation. In particular, we study the contribution of wave overwash of the plate (the wave running over the plate’s upper surface) to attenuation. Further, we use direct numerical simulations with the open-source code OpenFOAM to study the relationship between overwash and attenuation. Both the experimental measurements and the numerical simulations show a correlation between transmitted wave energy and overwash.