HomeHome

Complex Basal Thermal Transition Near the Onset of Petermann Glacier, Greenland

Wing Yin Chu; Dustin M. Schroeder; Helene Seroussi; Timothy T. Creyts; Robin E. Bell

Title:
Complex Basal Thermal Transition Near the Onset of Petermann Glacier, Greenland
Author(s):
Chu, Wing Yin
Schroeder, Dustin M.
Seroussi, Helene
Creyts, Timothy T.
Bell, Robin E.
Date:
Type:
Articles
Department(s):
Lamont-Doherty Earth Observatory
Persistent URL:
Book/Journal Title:
Journal of Geophysical Research: Earth Surface
Geographic Area:
Greenland
Abstract:
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 happens through alternating bands of frozen and thawed bands. The complex thermal state across the onset region suggests that lateral meltwater injection and local meltwater production determine the location of Petermann Glacier. Given the lack of topographic pinning at the onset location, the upstream margin of Petermann is vulnerable to migrate depending on a combination of advective cooling and meltwater supply from the interior of the ice sheet.
Subject(s):
Geophysics
Glaciology
Ice sheets--Mathematical models
Ice mechanics
Publisher DOI:
https://doi.org/10.1029/2017JF004561
Item views
10
Metadata:
text | xml
Suggested Citation:
Wing Yin Chu, Dustin M. Schroeder, Helene Seroussi, Timothy T. Creyts, Robin E. Bell, , Complex Basal Thermal Transition Near the Onset of Petermann Glacier, Greenland, Columbia University Academic Commons, .

Columbia University Libraries | Policies | FAQ