Presentation #513.01 in the session Fire and Ice: Europa and Aurorae.
A variety of studies have considered the thickness of Europa’s ice shell, though there is not a consensus on whether the shell is thick or thin. The discrepancy arises in part from the lack of information about ice viscosity relevant to Europa (and whether a Newtonian formulation is an appropriate description of ice rheology), and from the related question of whether heat is transported conductively or convectively across the shell. Here, we employ a 1D numerical model to consider the conductive growth of Europa’s ice shell subject to different basal heat fluxes, viscosities, and internal heating rates. Our model includes the effect of a moving boundary, representative of a growing ice cover. A Rayleigh number criterion governs the transition between conductive and convective heat transport. We describe the temporal evolution of the ice shell, and elucidate the parameter space under which the shell may switch from a conductive to convective regime. Our findings indicate that further understanding of ice rheology in the regime relevant to Europa is crucial to subsequent insights on ice shell thicknesses.