Thermodynamic consolidation and melting of sea ice ridges

Thermodynamic models describing consolidation of sea ice rubble and slush were formulated then explicit solutions of these models were constructed and analyzed. It was shown that the thermal inertia, the dependence of the specific heat capacity of sea ice on the temperature and the influence of brine salinity in the slush influence the consolidated layer thickness. The finite element method and the computer program FEMLAB were used to calculate consolidation and melting of the two-dimensional model of an ice ridge consisting of solid ice blocks, slush and sea water. Numerical simulations were carried out using five groups of input parameters characterizing the natural variability of environmental conditions and turbulent heat conductivity of sea water. Variations in ice volume and porosity, the thickness and shape of the consolidated layer, temperature distribution inside the ridge and heat fluxes from the ocean and into the atmosphere were analyzed depending on input parameters of the model. It was shown that vertical extension of the consolidated layer of a two-dimensional ridge can locally exceed the consolidated layer thickness calculated with a one-dimensional model. The results of the simulations were interpreted by analyzing of virtual “drilling” data. The average ridge porosity according to the drilling data was shown to be dependent on the number of drilling holes and their location on the ridge.