Earth  ID: 4097

Greenland's Mega-Canyon beneath the Ice Sheet

Subglacial topography plays an important role in modulating the distribution and flow of meltwater beneath the ice known as basal water flow. This animation portrays topographic data of the bedrock under the Greenland ice sheet derived from ice-penetrating radar data. Clearly evident in the topography is a 750-km-long subglacial canyon in northern Greenland that is likely to have influenced basal water flow from the ice sheet interior to the margin. The authors suggest that the mega-canyon predates ice sheet inception and has influenced basal hydrology in Greenland over past glacial cycles. (See reference under "Science Paper" below)

Starting with a view of the surface of Greenland, the animation zooms closer to the surface as the ice sheet is stripped away to reveal the false-colour topography of the bedrock that lies beneath. Regions above sea level are shown in shades of green while areas below zero are coloured by shades of brown. Yellow indicates the area near sea level. The topography is exaggerated from 12 to 40 times in order to accentuate the topographic relief. Visible in the topography from about the midpoint of Greenland to its Northwest coast is the 750-km-long subglacial canyon described by the authors.

 

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Visualization Credits

Cindy Starr (GST): Lead Visualizer
Greg Shirah (NASA/GSFC): Animator
Jefferson Beck (USRA): Producer
J. L. Bamber (School of Geographical Sciences, University of Bristol, UK): Scientist
Michael Studinger (NASA/GSFC): Scientist
Laurence Schuler (ADNET Systems, Inc.): Project Support
Ian Jones (ADNET Systems, Inc.): Project Support
Please give credit for this item to:
NASA's Goddard Space Flight Center Scientific Visualization Studio
The Blue Marble Next Generation data is courtesy of Reto Stockli (NASA/GSFC).

The Blue Marble data is courtesy of Reto Stockli (NASA/GSFC).

Science Paper:

Bamber, J.L., Siegert, M.J., Griggs, J.A., Marshall, S., Spada, G. Paleofluvial canyon drains subglacial water from northern Greenland, Science, 2013.

Bamber, J. L., Griggs, J. A., Hurkmans, R. T. W. L., Dowdeswell, J. A., Gogineni, S. P., Howat, I., Mouginot, J., Paden, J., Palmer, S., Rignot, E., and Steinhage, D.: A new bed elevation dataset for Greenland, The Cryosphere, 7, 499-510, 10.5194/tc-7-499-2013, 2013. (Available here.)

Short URL to share this page:
http://svs.gsfc.nasa.gov/4097

Missions:
Operation IceBridge
Terra

Data Used:
Greenland bed elevation dataset by Bamber, et al., 2013 1970 - 2012
Greenland Mapping Project (GIMP) Digital Elevation Model 2003 - 2009
Terra and Aqua/MODIS/Blue Marble: Next Generation 2004

Keywords:
SVS >> HDTV
DLESE >> Physical geography
GCMD >> Earth Science >> Land Surface >> Topography
GCMD >> Earth Science >> Cryosphere >> Glaciers/Ice Sheets >> Ice Sheets
GCMD >> Earth Science >> Hydrosphere >> Glaciers/Ice Sheets >> Ice Sheets
GCMD >> Earth Science >> Land Surface >> Topography >> Topographic Effects
GCMD >> Earth Science >> Land Surface >> Topography >> Topographical Relief
NASA Science >> Earth

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 8.0.0.0.0