Impacts of tide and cavity geometry on ocean-driven melting beneath the Nansen Ice Shelf

Mass loss from ice shelves occurs through ocean-driven melting regulated by dynamic and thermodynamic processes in sub-ice shelf cavities. However, the understanding of these oceanic processes is quite limited because of the scant observations under ice shelves. Here, a regional coupled sea-ice/ocean model that includes physical interactions between the ocean and the ice shelf is used as an alternative tool for exploring ocean-driven melting beneath the Nansen Ice Shelf (NIS), Terra Nova Bay (TNB), Antarctica.

We will first show the spatiotemporal variability signatures for different modes of ocean-driven melting at the base of the NIS. Our model includes detailed bathymetry and ice shelf base topography based on in-situ observation and has been run with and without tides. We have also investigated how tide and model geometries (i.e., cavity geometry) affect the water mass transformations and ice shelf melting/freezing regimes at the base of the ice shelf which significantly affect the ice shelf stability.