Scattering kernel of an array of floating ice floes:application to water wave transport in the marginal ice zone

• Published in: Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
• Main Authors: Montiel, F., Meylan, M. H., Hawkins, S. C.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2024
• Subjects: fast multipole method; multiple scattering; ocean waves; radiative transfer theory; sea ice; Sea ice
• Online Access: https://researchers.mq.edu.au/en/publications/a0cea58a-fde4-448c-9bca-f306e3dd0fe6; https://doi.org/10.1098/rspa.2023.0633; http://www.scopus.com/inward/record.url?scp=85184006791&partnerID=8YFLogxK; http://purl.org/au-research/grants/arc/DP220102243

A radiative transfer model of water wave scattering in the marginal ice zone is considered. In this context, wave energy redistribution across the directional components of the spectrum as a result of scattering by the constituent ice floes is typically modelled via a scattering kernel describing the far-field directionality of the scattered wave field produced by a single floe in isolation. Recognizing the potential importance of the floe size distribution (FSD) on wave scattering, we propose an enhanced scattering kernel constructed from the far-field scattering pattern of a circular array of floes. This is achieved by solving the self-consistent multiple scattering of a time-harmonic plane wave by a large array of floating circular floes with radii sampled from a prescribed FSD. A fast multipole method is implemented to accelerate the numerical estimation of the solution. Simulations are then conducted to characterize the properties of the scattering kernel for a range of configurations. It is found that the scattering kernel obtained for a wide array has a large, narrow transmission peak in the forward direction, while it uniformizes low-amplitude scattered waves in other directions. An idealized application to radiative transfer theory is also considered.