loading page

Ice Flow Speed Variability of the Vaughn Lewis Icefall, SE Alaska, From Tiltmeters
  • +4
  • Sicely V Sohn,
  • Galina Jonat,
  • Juliana Souza,
  • Anne F Yoland,
  • Emma Spezia,
  • Keeya Beausoleil,
  • Kiya L Riverman
Sicely V Sohn
North Carolina State University

Corresponding Author:[email protected]

Author Profile
Galina Jonat
Carleton University
Juliana Souza
Rubenstein School of Environment and Natural Resources, University of Vermont
Anne F Yoland
University of Toronto
Emma Spezia
University of Pisa
Keeya Beausoleil
University of Alberta
Kiya L Riverman
University of Portland


Icefalls are steep ice flow features that form over steps in bedrock elevation. With their high driving stresses, icefalls have long been assumed to have a constant ice flowspeed. This assumption has not been thoroughly tested as methods using satellite feature tracking rapidly loose coherence and long-term GPS installations on the ground are unlikely to be retrievable. In this study, we test the hypothesis that the Vaughan Lewis Icefall in Southeast Alaska experiences daily velocity variations with daily variations in subglacial hydrology. Using high resolution tiltmeters, we observe change in ice surface tilt across eight days at two sites near the glacier centerline. We find daily variation in ice surface tilt, suggesting there are variations in daily ice flowspeed velocity. A weak and lagged correlation with air temperature suggests that velocity variations may be due to daily variations in subglacial hydrology. Future modeling efforts focused on describing ice flow over icefalls should consider adding daily or seasonal velocity variations. These results additionally have implications for theoretical models of ogive formation, which could result from seasonal flow speed variations across icefalls.
08 Jan 2024Submitted to ESS Open Archive
13 Jan 2024Published in ESS Open Archive