Modelling Seasonal Sea-Ice Dynamics within the Nares Strait Using a Lagrangian Discrete Element Approach

The cryosphere is a critical components of Earth’s climate system, storing over two-thirds of the Earth’s freshwater supply and helping regulate radiative heat transfer between the Earth and the Sun. Sea-ice is perhaps the most dynamical piece of the cryosphere, experiencing large seasonal fluctuations, that have strong impacts on both marine biogeochemistry and animal migration patterns. In this regard, the ability to offer high-fidelity regional predictions of sea-ice/floe distributions is highly desirable. In the past elastic/visco-plastic continuum models have been successfully used to model large scale Arctic/Antartic seasonal sea-ice fluctuations. However, in smaller regional studies (1km resolution and lower), the discontinuous and nonlinear response of sea-ice, becomes difficult to resolve with continuum models. At these smaller length scales, Lagrangian models, like the discrete-element method (DEM), where each ice floe can be treated explicitly, can represent the underlying sea-ice dynamics more naturally. To this end, we utilize the Hopkins contact model within the Discrete Element Method for Sea-Ice (DEMSI) to examine seasonal sea-ice changes within the Kane Basin of the Nares Strait. Within this study we test the role that different sea-ice distributions have on the initial sea-ice fracture and breakup during the spring season. To test the robustness of the Hopkins contact model we also carry out both Sobol and Delta sensitivity analyses which examine how different contact parameters impact sea-ice dynamics.