Grounding Zones: The “Inland” Dynamic Interface Between Seawater, Outlet Glaciers, Subglacial Meltwater Routing, and Ice-Shelf Processes

Projections of sea-level rise from ice-sheet shrinkage in a warming world have large uncertainties, linked to limited knowledge of changes at the ocean-ice sheet interface. This interface most typically is modeled as a grounding line, across which still-connected ice flows into the ocean to float as an ice shelf, or where icebergs calve from a cliff before the ice begins to float. But, extensive and rapidly increasing evidence shows that this is really a grounding zone, and that processes in this grounding zone omitted from many models could exert major controls on sea-level rise.