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Abstract Fast ice flow on the Antarctic continent constitutes much of the mass loss from the ice sheet. However, geophysical methods struggle to constrain ice flow history at depth, or separate the signatures of topography, ice dynamics and basal conditions on layer structure. We develop and demonstrate a methodology to compare layer signatures in multiple airborne radar transects in order to characterize ice flow at depth, or improve coverage of existing radar surveys. We apply this technique to generate synthetic, along-flow radargrams and compare different deformation regimes to observed radargram structure. Specifically, we investigate flow around the central sticky spot of Whillans Ice Stream, West Antarctica. Our study suggests that present-day velocity flowlines are insufficient to characterize flow at depth as expressed in layer geometry, and streaklines provide a better characterization of flow around a basal sticky spot. For Whillans Ice Stream, this suggests that ice flow wraps around the central sticky spot, supported by idealized flow simulations. While tracking isochrone translation and rotation across survey lines is complex, we demonstrate that our approach to combine radargram interpretation and modeling can reveal critical details of past ice flow.
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This content will become publicly available on March 31, 2026
MorphoLayerTrace (MLT): A Modified Automated Radio-Echo Sounding Englacial Layer-tracing Algorithm for Englacial Layer Annotation in Ice Penetrating Radar Data
- Award ID(s):
- 2118285
- PAR ID:
- 10609847
- Publisher / Repository:
- ACM
- Date Published:
- ISBN:
- 9798400706295
- Page Range / eLocation ID:
- 605 to 612
- Format(s):
- Medium: X
- Location:
- Catania International Airport Catania Italy
- Sponsoring Org:
- National Science Foundation
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