Group Leader: Professor Pat Langhorne
The major ice shelves of Antarctica buffer the land-based continental ice sheets from the ravages of the ocean. Under natural circumstances, melting occurs deep in the ice shelf cavity. Being slightly less saline, this water rises to the surface, becoming supercooled on the way, and spills out under the coastal sea ice. The supercooled water contains ice crystals that accumulate and grow in a low porosity layer at the sea ice-water interface. As this layer freezes into the sea ice cover it contains a signature of processes that took place in the ice shelf cavity.
To interpret this ocean signature we examine the physical and isotopic properties of the sea ice cover and its crystallographic structure, concurrently with measurements of the upper ocean. We then use these observations to build models of these processes. This work has been carried out in partnership with NIWA and Callaghan Innovation.