Landfast ice is nearly immobile sea ice attached to the coast. Despite
the important role of landfast ice in coastal climates, landfast ice is
not well simulated in current sea ice models and needs to be
parameterized. The mechanism for landfast ice formation is linked to the
local geography. Grounded ice ridges act as anchoring points in shallow
water. Sea ice arching between offshore island chains can lead to
landfast ice in deep water. Previous studies successfully represented
landfast ice in shallow marginal seas using bathymetry information to
implement a grounding scheme, but this method fails in deep regions.
This paper develops a new parameterization for coarse resolution sea ice
models using lateral drag as a function of sea ice thickness, drift
velocity, and coastline length. The new parameterization is tested in a
36 km pan-Arctic sea ice-ocean simulation. The simulated landfast ice in
the model run is compared to observations from satellite data. With the
lateral drag parameterization, representation of landfast ice improves
in deep marginal seas. The combination of the lateral drag
parameterization and a grounding scheme leads to a realistic landfast
ice distribution in most Arctic regions.