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Ice sheets reshape Earth’s surface. Maps of the landscape formed by past ice sheets are our best tool for reconstructing historic ice sheet behavior. But models of glacier erosion and deposition that explain mapped features are relatively untested, and without observations of landforms developing in situ, postglacial landscapes can provide only qualitative insight into past ice sheet conditions. Here we present the first swath radar data collected in Antarctica, demonstrating the ability of swath radar technology to map the subglacial environment of Thwaites Glacier (West Antarctica) at comparable resolutions to digital elevation models of deglaciated terrain. Incompatibility between measured bedform orientation and predicted subglacial water pathways indicates that ice, not water, is the primary actor in initiating bedform development at Thwaites Glacier. These data show no clear relationship between morphology and glacier speed, a weak relationship between morphology and basal shear stress, and highlight a likely role for preexisting geology in glacial bedform shape.
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This content will become publicly available on October 1, 2026
Holocene glacier-climate history of the Calluqueo glacier and Monte San Lorenzo, central Patagonia
- Award ID(s):
- 1804816
- PAR ID:
- 10612455
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Quaternary Science Reviews
- Volume:
- 366
- Issue:
- C
- ISSN:
- 0277-3791
- Page Range / eLocation ID:
- 109482
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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