David M. Holland, Courant Institute/NYU
Landfast ice is sea ice which forms and remains fast along a coast, where it is attached either to the shore, an ice wall, an ice front, or between shoals or grounded icebergs. Landfast ice is important because it fundamentally modifies, relative to pack ice, the momentum exchange between atmosphere and ocean and thus the location of upwelling and downwelling zones. It also affects the heat and freshwater exchange between air and ocean and consequently impacts where dense waters are produced. It has biological relevance too, for instance, on the ability of penguins to gain access to the open ocean. Current-generation sea-ice models are not capable of reproducing certain aspects of the processes of landfast ice formation, maintenance, and disintegration. In this study, we alter the standard sea-ice rheology so as to include tensile stresses. These stresses are formulated as a function of sea-ice salinity, temperature, age, and thickness. Using a limited-domain, high-resolution model, some ability to model landfast ice features is demonstrated.