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1. Radar‐Detected Englacial Debris in the West Antarctic Ice Sheet

   https://doi.org/10.1029/2019GL084012  

   Winter, Kate; Woodward, John; Ross, Neil; Dunning, Stuart A.; Hein, Andrew S.; Westoby, Matthew J.; Culberg, Riley; Marrero, Shasta M.; Schroeder, Dustin M.; Sugden, David E.; et al (September 2019, Geophysical Research Letters)
2. TSSA: two-step semi-supervised annotation for englacial radargrams on the Greenland ice sheet

   A. Jebeli; B. A. Tama; V. Janeja; N. Holschuh; C. Jensen; M. Morlighem; J. A MacGregor; M. Fahnestock (July 2023, IEEE International Geoscience and Remote Sensing Symposium)
3. Interpreting englacial layer deformation in the presence of complex ice flow history with synthetic radargrams

   https://doi.org/10.1017/aog.2019.41  

   Elsworth, Cooper W.; Schroeder, Dustin M.; Siegfried, Matthew R. (January 2020, Annals of Glaciology)

   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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4. A comparison of automated approaches to extracting englacial-layer geometry from radar data across ice sheets

   https://doi.org/10.1017/aog.2020.42  

   Delf, Richard; Schroeder, Dustin M.; Curtis, Andrew; Giannopoulos, Antonios; Bingham, Robert G. (April 2020, Annals of Glaciology)

   null (Ed.)

   Abstract Radar surveys across ice sheets typically measure numerous englacial layers that can often be regarded as isochrones. Such layers are valuable for extrapolating age–depth relationships away from ice-core locations, reconstructing palaeoaccumulation variability, and investigating past ice-sheet dynamics. However, the use of englacial layers in Antarctica has been hampered by underdeveloped techniques for characterising layer continuity and geometry over large distances, with techniques developed independently and little opportunity for inter-comparison of results. In this paper, we present a methodology to assess the performance of automated layer-tracking and layer-dip-estimation algorithms through their ability to propagate a correct age–depth model. We use this to assess isochrone-tracking techniques applied to two test case datasets, selected from CreSIS MCoRDS data over Antarctica from a range of environments including low-dip, continuous layers and layers with terminations. We find that dip-estimation techniques are generally successful in tracking englacial dip but break down in the upper and lower regions of the ice sheet. The results of testing two previously published layer-tracking algorithms show that further development is required to attain a good constraint of age–depth relationships away from dated ice cores. We recommend that auto-tracking techniques focus on improved linking of picked stratigraphy across signal disruptions to enable accurate determination of the Antarctic-wide age–depth structure. 

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5. Joint Estimation of Ice Sheet Vertical Velocity and Englacial Layer Geometry from Multipass Synthetic Aperture Radar Data

   https://doi.org/10.1109/PAST49659.2022.9974985  

   Ariho, Gordon; Paden, John D.; Hoffman, Andrew; Christianson, Knut A; Holschuh, Nicholas (October 2022, 2022 IEEE International Symposium on Phased Array Systems & Technology (PAST))