Articles | Volume 15, issue 2
https://doi.org/10.5194/tc-15-897-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-15-897-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Feb 2021
Research article |
| 19 Feb 2021
| 19 Feb 2021
The cooling signature of basal crevasses in a hard-bedded region of the Greenland Ice Sheet
Ian E. McDowell
CORRESPONDING AUTHOR
Department of Geology and Geophysics, University of Wyoming, Laramie,
Wyoming, 82071, USA
Graduate Program of Hydrologic Sciences, University of Nevada, Reno, Nevada, 89557, USA
Neil F. Humphrey
Department of Geology and Geophysics, University of Wyoming, Laramie,
Wyoming, 82071, USA
Joel T. Harper
Department of Geosciences, University of Montana, Missoula, Montana,
59812, USA
Toby W. Meierbachtol
Department of Geosciences, University of Montana, Missoula, Montana,
59812, USA
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Short summary
Ice temperature controls rates of internal deformation and the onset of basal sliding. To identify heat transfer mechanisms and englacial heat sources within Greenland's ablation zone, we examine a 2–3-year continuous temperature record from nine full-depth boreholes. Thermal decay after basal crevasses release heat in the near-basal ice likely produces the observed cooling. Basal crevasses in Greenland can affect the basal ice rheology and indicate a potentially complex basal hydrologic system.
Ice temperature controls rates of internal deformation and the onset of basal sliding. To...
