The Geomorphic Record of Marine-Based Ice Dome Decay: Final Collapse of the Barents Sea Ice Sheet

Abstract

New high-resolution geophysical data acquired from eastern Storbanken in the central Barents Sea allow reconstruction of the flow of marine-based ice dome during the final stages of ice-sheet decay. Ice-marginal and subglacial landforms show diverging and quasi-radial grounding-line retreat patterns, implying that an isolated, dynamic, shrinking ice dome was centred at ∼77° N 40° E on eastern Storbanken prior to final marine-based ice-sheet collapse. This geomorphological reconstruction contrasts with previous numerical and observational models that infer a northward-migrating ice dome or crest that extended longitudinally from Svalbard to Franz-Josef Land prior to its eventual demise. Our results provide an important past analogue for late-stage decay of marine ice domes, as well as robust empirical constraints that can be used to calibrate numerical models simulating the behaviour of marine-based ice sheets in a warming environment.