Lifecycle of sea ice floes reproduced using a new discrete element sea ice model

The multi-scale nature of sea ice presents a major challenge for mathematical modeling of sea ice characteristics such as floe size and thickness distributions and the formation of leads. To address this issue, we created SubZero, a newly developed discrete element sea ice model that can mimic the lifecycle of individual sea ice floes. SubZero represents sea ice as a collection of strongly interacting polygonal floes with time-evolving boundaries in response to parameterized processes such as ridging, fracturing, and welding. We demonstrate how such a unique model can generate the power-law distribution of floe sizes and gamma function-like ice thickness distribution similar to observational estimates. We also show that the statistical characteristics of linear kinematic features in this model depend on the fracture rules of individual floes and the bonds between them. The ability to simulate the lifecycle of floes with complex shapes is a crucial improvement of SubZero over previous discrete element sea ice models that allows long-term simulations to achieve realistic floe-scale sea ice characteristics.