Glacier Terminus Morphology Informs Calving Style

Terminus change is a complex outcome of ice-ocean boundary processes and poses challenges for ice sheet models due to inadequate calving laws, creating uncertainty in sea level change projections. To address this, we quantify glacier termini sinuosity and convexity, testing the hypothesis that terminus morphology reflects dominant calving processes. Using 10 glaciers with diverse calving styles in Greenland over the period from 1985 to 2021, we establish a supervised classification of calving style by comparing morphology and literature-derived calving observations. Validation with four of these glaciers and flotation conditions and subglacial discharge routing observations confirms concave, smooth termini indicate buoyant flexure dominated-calving, while convex, sinuous termini suggest serac failure dominated-calving. We also identify a mixed style where both calving types may occur. We use these classes to label calving style from 1985 to 2021 for all 10 glaciers and explore how this changes over time as glaciers retreat.