Mapping the ratio of meteoric and continental ice in Antarctic Ice Shelves as a metric for susceptibility to future climate change

Ice shelves encircling the Antarctic perimeter buttress ice flow from the continent towards the ocean, and their evolution and integrity are governed by surface accumulation, basal melting, and ice dynamics. The disintegration of ice shelves, caused by future changes in the climate, leads to an increase in ice discharge towards the ocean and a consequent increase in global sea level – making their future stability important.

In this study we focus on the structure and composition of ice shelves. We model ice shelf stratigraphy for all ice shelves around Antarctica using a simplistic and observationally driven ice-dynamic forward model (validated on the Roi Baudouin Ice Shelf, Visnjevic et al., 2022), and map spatial variations in the percentage of locally accumulated ice on the ice shelf (local meteoric ice - LMI) compared to the ice inflowing from the continental ice sheet (continental meteoric ice - CMI). We investigate differences between LMI and CMI dominated ice shelves in the context of ice shelf stability, and discuss their susceptibility to future atmospheric and oceanic changes in climate. Expanding the analysis to the continental scale allows us to identify zones where future changes in climate might strongly impact ice shelf geometry and composition.