Abstract

Surface meltwater ponding has been implicated in the recent break-up of ice shelves along the Antarctic Peninsula. I will present some observations of ponds on Larsen C ice shelf and show how they coincide with troughs in the surface mapped using synthetic aperture radar (SAR) interferometry. For ponds to form, the ice shelf surface needs to have undergone sufficient melt/refreeze cycles to densify the ice to the point at which it is impermeable to continued melt. It is relatively straightforward to spot surface ponding in optical satellite imagery but detecting liquid water within an unsaturated snow pack requires observations in the microwave. I will show how QuikSCAT and, recently available, enhanced resolution ASCAT radar scatterometry data reveals patterns and trends in melt on the ice shelf from 1999-2017. Finally, I will show how we used interferometry and the Sentinel 1 SAR data to monitor the progression of the rift which caused the recent calving of the 5,800 km2 ice berg from Larsen C.