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Updated: Jan 25, 2026

Generation of Dynamical Environmental Conditions using a High-Throughput Microfluidic Device
Published on: April 17, 2021
Ice-stream demise dynamically conditioned by trough shape and bed strength
Tom Bradwell1,2, David Small3, Derek Fabel4
1Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, UK.
Abstract:
Ice sheet mass loss is currently dominated by fast-flowing glaciers (ice streams) terminating in the ocean as ice shelves and resting on beds below sea level. The factors controlling ice-stream flow and retreat over longer time scales (>100 years), especially the role of three-dimensional bed shape and bed strength, remain major uncertainties. We focus on a former ice stream where trough shape and bed substrate are known, or can be defined, to reconstruct ice-stream retreat history and grounding-line movements over 15 millennia since the Last Glacial Maximum. We identify a major behavioral step change around 18,500 to 16,000 years ago-out of tune with external forcing factors-associated with the collapse of floating ice sectors and rapid ice-front retreat. We attribute this step change to a marked geological transition from a soft/weak bed to a hard/strong bed coincident with a change in trough geometry. Both these factors conditioned and ultimately hastened ice-stream demise.
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