Complex Basal Thermal Transition Near the Onset of Petermann Glacier, Greenland ...
The basal thermal regime of ice sheets exerts a strong control on ice‐sheet stability and the onset of rapidly streaming flow. However, the nature of this thermal transition where sliding initiates is largely unconstrained by geophysical observations. In the Greenland Ice Sheet, topographic troughs...
Main Authors: | , , , , |
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Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Columbia University
2018
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Subjects: | |
Online Access: | https://dx.doi.org/10.7916/d8vm5vr3 https://academiccommons.columbia.edu/doi/10.7916/D8VM5VR3 |
Summary: | The basal thermal regime of ice sheets exerts a strong control on ice‐sheet stability and the onset of rapidly streaming flow. However, the nature of this thermal transition where sliding initiates is largely unconstrained by geophysical observations. In the Greenland Ice Sheet, topographic troughs or elevated geothermal heat fluxes typically define the onset of outlet glaciers. In contrast, Petermann Glacier in Northern Greenland does not have any distinct bed troughs or localized geothermal heating associated with its onset, making it an ideal site to investigate the basal thermal state and examine its role in the onset of Petermann Glacier. Here we use radar bed reflectivity and an ice‐sheet thermomechanical model to examine the basal thermal regime beneath Petermann Glacier. Our results reveal a complex thermal transition near the onset of Petermann Glacier. As the bed shifts from largely frozen to largely thawed with increasing distances from the ice divide, our results show that this thermal transition ... |
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