Subglacial topography and geothermal heat flux: potential interactions with drainage of the Greenland ice sheet

• Published in: Geophysical Research Letters
• Main Authors: van der Veen, Cornelis J., Leftwich, T., von Frese, R., Csatho, Bea M., Li, Jilu
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union 2015
• Subjects: geothermal heat; glaciers; Topography; Greenland; Jakobshavn Isbræ; Ice Sheet; Jakobshavn; Jakobshavn isbræ
• Online Access: http://hdl.handle.net/1808/17298; https://doi.org/10.1029/2007GL030046

This is the published version, also available here: http://dx.doi.org/10.1029/2007GL030046. [1] Many of the outlet glaciers in Greenland overlie deep and narrow trenches cut into the bedrock. It is well known that pronounced topography intensifies the geothermal heat flux in deep valleys and attenuates this flux on mountains. Here we investigate the magnitude of this effect for two subglacial trenches in Greenland. Heat flux variations are estimated for idealized geometries using solutions for plane slopes derived by Lachenbruch (1968). It is found that for channels such as the one under Jakobshavn Isbræ, topographic effects may increase the local geothermal heat flux by as much as 100%.