This project will attempt to quantify the effects of sea ice and ice transport on the presence and persistence of high latitude oceanic salinity anomalies, and , more generally, on the circulation of the global oceans. Past global modelling efforts have included only rudimentary ice dynamics and thermodynamics, while sea ice models have generally neglected the large-scale oceanic effects of the sea ice. This project will couple an ice-ocean model that includes full sea ice dynamics to a baroclinic ocean model. By varying the fraction of the included global ocean, the sea ice effect can be explicitly demonstrated. A series of numerical studies will be concerned with the question of how critical ice export, or equatorward ice transport, is on regional salinity budgets, and how much of a variation in the ice budget can affect the thermohaline circulation of geographically realistic ocean basins. After separate studies of the northern and southern hemisphere ice-ocean circulation models, a complete model will be constructed for the Atlantic Ocean. With this model it is anticipated that an asymmetrical global mode of the thermohaline circulation can be obtained, which may then be perturbed in order to assess the global-scale effect of modified ice transport from the Arctic Basin and the Antarctic circumpolar region.
