Evolution of ice-shelf damage at Pine Island Ice Shelf using Elmer/ice and multiple satellite derived observations

The stability of the Antarctic Ice Sheet is a key control on global sea-level rise, with ice shelves acting as critical regulators of glacier discharge into the ocean. Understanding the processes governing ice-shelf stability and glacier dynamics is therefore essential for improving projections of future sea-level change. Pine Island Glacier is among the most rapidly changing glaciers on Earth and plays a major role in Antarctic mass loss, currently ranking as the largest single contributor to Antarctic-driven global mean sea-level rise. Between 1992 and 2011, the Pine Island grounding line retreated by approximately 31 km, leading to a substantial increase in ice discharge. This dynamic evolution has been accompanied by weakening of shear margins and increased ice damage, expressed by the proliferation of crevasses and rifts, which reduces the glacier's ability to transmit resistive stresses. In this study, we simulate the evolution of damage in the Pine Island Ice Shelf using the Elmer/Ice finite-element model. We invert for ice viscosity and the related ice damage under the shallow shelf approximation. We investigate the sensitivity of modeled damage to different ice-thickness datasets derived from radar and laser altimetry as well as satellite photogrammetry, all constrained by the same surface velocity observations. We further assess the impact of dataset spatial resolution on the inferred damage fields and compare the results with fracture maps derived using deep learning on satellite imagery. To evaluate temporal changes, we perform a serie of inversions spanning 1992–2022, using time-evolving observations of surface velocity and ice-shelf thickness. Finally, we compare the evolution of ice-shelf damage with changes in the ice-shelf buttressing index to assess the overall influence of damage on the stability of Pine Island Glacier over the past decades. This study was funded as part of the ERC-research project IceDaM.