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. Plain Language Summary: The ice‐ocean boundary (terminus) of the Greenland ice sheet changes over space and time due to the melt and calving of ice. There is a range of calving behaviors due to many environmental and geometric factors, including changing ocean temperatures, glacier melting, and the geometry of the glacier. This makes representing how these boundary changes in ice sheet models are difficult, leading to uncertainties in predicting sea level rise from retreating glaciers. The study focuses on the shape (morphology) of 10 glaciers from 1985 to 2021, finding that smooth, concave termini indicate a type of calving related to the flotation of the glacier, while sinuous, convex termini indicate melt‐dominated calving. The research helps classify calving styles and understand how they change over time as glaciers retreat. Key Points: Two calving styles are linked to distinct terminus morphologies but both can exist for a single glacier (over time or space)Mixed styles of calving are more difficult to classifyClassifying terminus morphology over time can aid in identifying how terminus calving mechanisms change over time [ABSTRACT FROM AUTHOR]