Sack Lunch Seminar (SLS)

Scaling properties of Arctic sea ice deformation in high-resolution viscous-plastic sea ice models

Many climate models use a rheology of the viscous-plastic type to simulate sea ice dynamics. With this rheology, large scale velocity and thickness fields can be realistically simulated, but the representation of small scale deformation rates and Linear Kinematic Features (LKF) is thought to be inadequate. However, at high resolution (< 5 km) the rheology starts to produce lines of localised deformation rates. In this study we use results from a 1-km Pan-Arctic model to investigate the influence of these deformation features on the scaling properties of sea ice deformation. For evaluation the EGPS satellite data set of small-scale sea ice kinematics for the Central Arctic (successor of RGPS) is used.
The modelled sea ice deformation shows multi-fractal spatial scaling and, in this sense, agrees with the satellite data. In addition, the temporal coupling of the spatial scaling is reproduced as well. Furthermore, we examine the regional and seasonal variations of spatial scaling properties and its dependence on the ice condition, i.e. sea ice concentration and thickness, which are in agreement with previous RGPS studies.