Theoretical and experimental modelling of the turbulent dissolution of a vertical ice wall in salty water, and its application to the ablation of icebergs and ice shelves.

Tuesday, 16 December 2014
Ross C Kerr, Australian National University, Canberra, ACT, Australia and Craig McConnochie, Australian National University, Canberra, Australia
We examine theoretically and experimentally the dissolution of a vertical ice wall in the case where the heat and salt transfer is driven by turbulent compositional convection. A theoretical model of the turbulent dissolution is first developed, which predicts the interface temperature, interface concentration and interface dissolution velocity. The analysis is then tested by comparing it with laboratory measurements of the ablation of a vertical ice wall in contact with salty water. The model is found to accurately predict both the dissolution velocity and the interface temperature, for water temperatures up to about 6 degrees Celsius, where there is a transition from turbulent dissolution to turbulent melting. When applied to the ablation of icebergs and ice shelves in contact with seawater, we predict convective dissolution velocities in good agreement with field observations.