In-Woo Park: Coupling rate-based calving with continuum damage evolution model
Floating ice shelves do not directly contribute to global mean sea level (GMSL) rise; however, they exert a buttressing effect on the grounded ice sheet. In particular, the collapse of a confined ice shelf, for example through calving, reduces this buttressing effect, thereby accelerating ice discharge into the ocean and contributing to further GMSL rise. Prior to calving, damage (e.g., crevasses) accumulates in the ice due to tensile stresses, particularly along shear margins. However, regional-scale ice-sheet models have generally lacked consideration of how the memory of accumulated damage influences subsequent calving. To address this gap, we couple a continuum damage model (CDM) with a rate-based calving approach in the Ice-sheet and Sea-level System Model (ISSM) to investigate damage-induced acceleration of calving. To systematically investigate the CDM and its coupling with rate-based calving, we idealize the model domain based on the Marine Ice Sheet Model Intercomparison Project (MISMIP). First, we investigate standalone damage evolution using different failure criteria, including the Hayhurst, maximum principal stress, and von Mises criteria, together with their corresponding thresholds for damage initiation. Second, we couple the CDM with the rate-based calving approach using the tensile von Mises criterion.