Simulating UNder ice Shelf Extreme Topography (SUNSET)

The accelerating rise in global sea levels, driven significantly by the melting of the Antarctic and Greenland ice sheets, demands accurate forecasts to help policymakers develop effective mitigation and adaptation strategies, given the profound economic and societal consequences. The largest ice-sheet contribution to sea level occurs when the ocean melts the base of ice shelves (floating extensions of the grounded ice sheet), increasing the flow of grounded ice into the ocean.

The project aims to investigate how extreme topography on the underside of ice shelves changes ocean currents and melting. Beneath ice shelves with a smooth, gradually sloping base, melting can be viewed as a vertical process, and this is how it is currently represented in climate models. However, observations show that melting on the steeply sloping sides of extreme ice topography is actually horizontal, and much faster than the melting of a smooth ice base. Furthermore, turbulent ocean eddies generated by extreme topographic features push warm water towards the ice, intensifying the melting process.

Utilising field study and computer simulations, a new representation of the effect of extreme ice topography in climate models will be developed. In light of the simulations, the project will develop mathematical formulae to represent the influence of extreme ice topography which will be implemented into the ocean model and tested for its ability to represent the influence of extreme ice topography in climate models.