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

  title={Subglacial topography and geothermal heat flux: Potential interactions with drainage of the Greenland ice sheet},
  author={Cornelis J. van der Veen and Timothy E. Leftwich and Ralph R. B. von Frese and Be{\'a}ta M. Csath{\'o} and J. Li},
  journal={Geophysical Research Letters},
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… 

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