Earth  ID: 4022

Measuring Elevation Changes on the Greenland Ice Sheet

Since the late 1970's, NASA has been monitoring changes in the Greenland Ice Sheet. Recent analysis of seven years of surface elevation readings from NASA's ICESat satellite and four years of laser and and ice-penetrating radar data from NASA's airborne mission Operation IceBridge shows us how the surface elevation of the ice sheet has changed.

The colors shown on the surface of the ice sheet represent the accumulated change in elevation since 2003. The light yellow over the central region of the ice sheet indicates a slight thickening due to snow. This accumulation, along with the weight of the ice sheet, pushes ice toward the coast. Thinning near coastal regions, shown in green, blue and purple, has increased over time and now extends into the interior of the ice sheet where the bedrock topography permits. As a result, there has been an average loss of 300 cubic kilometers of ice per year between 2003 and 2012.

This animation portrays the changes occurring in the surface elevation of the ice sheet since 2003 in three drainage regions: the southeast, the northeast and the Jakobshavn regions. In each region, the time advances to show the accumulated change in elevation from 2003 through 2012.

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Above: Move bar to compare the change in surface elevation (left) to the bedrock topography (right) in the northeast region. Download HTML to embed this in your web page.

The ice sheet is cut away to reveal how the bedrock topography beneath the ice sheet affects the movement of glacial ice in each region. The bedrock topography is colored by elevation with areas below sea level shown in brown and areas above sea level shown in green. Yellow indicates regions at sea level.


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Above: Move bar to compare the change in the surface elevation (left) to the bedrock topography (right) in the Jakobshavn region. Download HTML to embed this in your web page.

The bedrock topography affects the movement of the ice sheet. Blue/white velocity flows indicate the direction and speed of the ice over time. Slower moving ice is shown as shorter blue flow lines while faster moving ice is shown as longer white flow lines.

 

Related


Visualization Credits

Cindy Starr (GST): Lead Visualizer
Horace Mitchell (NASA/GSFC): Animator
Greg Shirah (NASA/GSFC): Animator
Cindy Starr (GST): Video Editor
Jefferson Beck (USRA): Narrator
Jefferson Beck (USRA): Producer
Babonis Greg (University at Buffalo): Scientist
J. L. Bamber (School of Geographical Sciences, University of Bristol, UK): Scientist
Beata Csatho (University at Buffalo): Scientist
J. A. Dowdeswell (University of Cambridge): Scientist
Ian Howat (Ohio State University): Scientist
R. T. W. L. Hurkmans (University of Bristol): Scientist
P. Gogineni (Electrical Engineering and Computer Science, University of Kansas): Scientist
J. A. Griggs (School of Geographical Sciences, University of Bristol): Scientist
Jeremie Mouginot (University of California, Irvine): Scientist
J. Paden (University of Kansas): Scientist
S. Palmer (University of Cambridge): Scientist
Eric J. Rignot (NASA/JPL CalTech): Scientist
Tony Schenk (University at Buffalo): Scientist
D. Steinhage (Alfred Wegener Institute): Scientist
Michael Studinger (NASA/GSFC): Scientist
Ian Jones (ADNET Systems, Inc.): Project Support
Laurence Schuler (ADNET Systems, Inc.): Project Support
Lori Perkins (NASA/GSFC): Project Support
Jefferson Beck (USRA): Writer
Cindy Starr (GST): Writer

IceBridge Project Manager: Christy Hansen (Stinger Ghaffarian Technologies)

IceBridge Education and Outreach: George Hale (Telophase Corporation)

Spacecraft Models courtesy of Chris Meaney (Honeywell Technology Solutions)

Aircraft Model courtesy of Scott Hanger (NASA)

Glacier footage provided courtesy of James Balog, Extreme Ice Survey
earthvisiontrust.org and www.extremeicesurvey.org

Elevation change over Greenland provided courtesy of
Beata Csatho, University at Buffalo

Greenland ice sheet velocity data provided courtesy of
Eric Rignot (NASA/JPL)

Greenland bed elevation provided courtesy of Bamber, et al.,
A new bed elevation dataset for Greenland,
The Cryosphere, 7, 499-510, doi:10.5194/tc-7-499-2013, 2013.

Greenland Mapping Project (GIMP) Digital Elevation Model provided courtesy of
the BPRC Glacier Dynamics Research Group, Ohio State University

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

Please give credit for this item to:
NASA's Goddard Space Flight Center Scientific Visualization Studio

Short URL to share this page:
http://svs.gsfc.nasa.gov/4022

Missions:
Ice, Cloud, and land Elevation Satellite (ICEsat)
Operation IceBridge

Data Used:
Greenland Ice Sheet Velocity
Greenland bed elevation dataset by Bamber, et al., 2013
Greenland Mapping Project (GIMP) Digital Elevation Model
ICESat and IceBridge/Annual Elevation of the Greenland Ice Sheet from 2003 through 2012 2003 - 2012

This item is part of this series:
Narrated Movies

Keywords:
SVS >> HDTV
GCMD >> Earth Science >> Cryosphere >> Glaciers/Ice Sheets >> Ice Sheets
GCMD >> Earth Science >> Hydrosphere >> Glaciers/Ice Sheets >> Ice Sheets
GCMD >> Location >> Greenland
DLESE >> Narrated
NASA Science >> Earth
GCMD >> Earth Science >> Terrestrial Hydrosphere >> Glaciers/ice Sheets >> Ice Sheets

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