Articles | Volume 9, issue 3
Model description paper
01 Apr 2016
Model description paper |  | 01 Apr 2016

Discrete-Element bonded-particle Sea Ice model DESIgn, version 1.3a – model description and implementation

Agnieszka Herman

Abstract. This paper presents theoretical foundations, numerical implementation and examples of application of the two-dimensional Discrete-Element bonded-particle Sea Ice model – DESIgn. In the model, sea ice is represented as an assemblage of objects of two types: disk-shaped "grains" and semi-elastic bonds connecting them. Grains move on the sea surface under the influence of forces from the atmosphere and the ocean, as well as interactions with surrounding grains through direct contact (Hertzian contact mechanics) and/or through bonds. The model has an experimental option of taking into account quasi-three-dimensional effects related to the space- and time-varying curvature of the sea surface, thus enabling simulation of ice breaking due to stresses resulting from bending moments associated with surface waves. Examples of the model's application to simple sea ice deformation and breaking problems are presented, with an analysis of the influence of the basic model parameters ("microscopic" properties of grains and bonds) on the large-scale response of the modeled material. The model is written as a toolbox suitable for usage with the open-source numerical library LIGGGHTS. The code, together with full technical documentation and example input files, is freely available with this paper and on the Internet.

Short summary
Recent developments in observational and modeling techniques allow us to analyze sea ice with increasingly higher resolution. Instead of a continuous ice cover we observe a complex, constantly changing medium composed of interacting floes. Understanding these aspects of sea ice behavior requires new modeling methods, like the Discrete-Element Sea Ice model (DESIgn) in which sea ice is treated as an assemblage of grains that freeze together or break apart in response to wind and ocean currents.