Geometric controls of tidewater glacier dynamics

Abstract. Retreat of marine outlet glaciers often initiates depletion inland ice through dynamic adjustments the upstream glacier. The local topography a fjord may promote or inhibit such retreat, and therefore geometry constitutes critical control on sheet mass balance. To quantify processes ice–topography interactions enhance understanding dynamics involved, we analyze multitude topographic settings scenarios using Ice-sheet Sea-level System Model (ISSM). We systematically study glacier retreat variety artificial geometries modeled directly in relation to features. find that an upstream-widening upstream-deepening does not necessarily as suggested by previous studies. Conversely, it stabilize because converging flow towards constriction enhances lateral basal shear stress gradients. An upstream-narrowing upstream-shoaling fjord, turn, since walls bed provide little stability where diverges. Furthermore, identify distinct quantitative relationships linking grounding line discharge rate transfer these results long-term Jakobshavn Isbræ. These findings offer new perspectives give guidance ad hoc assessment future topographically induced loss based knowledge geometry.