We’re interested in the role of grounding line dynamics on Antarctic glacier stability. Using numerical models with a range of complexities, we assess the evolution of glaciers with different bed slopes at their grounding lines, testing the long-standing belief that glaciers with reverse bed slopes are inherently unstable by incorporating high-resolution measurements into ice flow models.

These high-resolution measurements include 3D tomography measurements under the current ice sheet (derived by CReSIS colleagues) and ice-marginal landforms (moraines, grounding zone wedges) beneath the deglaciated Antarctic continental shelf (derived by collaborator Lauren Simkins). These landforms indicate considerable spatial and temporal variability in grounding line behavior, with patterns of retreat ranging between steady, small-scale retreat events of several hundred meters in distance to large retreat events of 10s of kilometers punctuated by periods of stability.

Interaction between grounding-line migration and basal topography (Thomas, 1979).