Damage intensity increases ice mass loss from Thwaites Glacier, Antarctica

Abstract. Ice damage, which results from the formation and development of crevasses on glaciers, plays a critical role in ice-shelf stability, grounding-line retreat, and subsequent sea-level rise. Yet, few ice-sheet models explicitly account for ice damage or its effects on glacier dynamics. Here, we incorporate ice damage processes into an ice-sheet model and apply it to the Thwaites Glacier basin to assess the sensitivity of mass loss to ice damage intensity. Our results indicate that, when accounting for ice damage mechanics, the ice-sheet model captures the observed ice geometry and mass balance of Thwaites Glacier during the historical period (1990–2020). On multidecadal–centennial timescales, ice damage facilitates the collapse of Thwaites Glacier, significantly increasing ice mass loss. When extending simulations to the year 2300, we show that accounting for ice damage results in more than twice the ice mass loss compared to simulations that neglect ice damage mechanics. This study highlights the necessity of explicitly representing ice damage processes in ice-sheet models to improve projections of future ice loss and sea-level rise.