Earth  ID: 3522

Recent Glacier Mass Changes in the Gulf of Alaska Region from GRACE Mascon Solutions

Visualizations by Lori Perkins Released on November 12, 2008
Mass changes of the Earth's ice sheets and glacier systems are of considerable importance because of their sensitivity to climate change and their contribution to rising sea level. Recent changes in the cryosphere highlight the importance of methods for directly observing the complex spatial and temporal variation of land ice mass flux. Since its launch in March of 2002, the NASA/DLR Gravity Recovery and Climate Experiment (GRACE) mission has been acquiring ultra-precise inter-satellite K-band range and range-rate (KBRR) measurements enabling a direct mapping of static and time-variable gravity. These data provide new opportunities to observe and understand ice mass changes at unprecedented temporal and spatial resolutions. In order to improve upon the ice mass change observations derived from GRACE, we have employed unique data analysis approaches to obtain lumped harmonic local mass concentration solutions (mascon solutions) from GRACE inter-satellite range-rate measurements. We have computed multi-year time series of surface mass flux for Greenland and Antarctica coastal and interior ice sheet sub-drainage systems as well as the Alaskan glacier systems. These mascon solutions provide important observations of the seasonal and inter-annual evolution of the Earth's land ice. Additionally, these solutions facilitate a detailed comparison to surface elevation change observations from spaceborne and airborne laser altimetry as well as surface melt observations. We present our latest mascon solutions of the Alaska mountain glaciers. We compare these mass flux solutions to ICESat and airborne laser altimeter observations of surface elevation change as well as surface melt observations derived from MODIS data. The combination of GRACE high-resolution mass flux observations together with the surface elevation change and surface melt observations is beginning to reveal a detailed understanding of the Earth's high latitude land ice evolution.
Download Options
The mass changes of the Gulf of Alaska glaciers are computed from the Gravity Recovery and Climate Experiment (GRACE) inter-satellite rate data from April 2003 through September 2007. Using space-borne gravity measurements to assess glacier mass balance NASA scientists determine mass variations along the Gulf of Alaska, an area apanning 18,919 square miles. Areas of deep blue like the areas around Glacier Bay and the Yakutat Icefield represent significant mass loss where inland areas of dark gray represent slight mass gains.
Download Options
Same image as above without labels
Download Options
Glacier Mass Rate of Change color table
Download Options
The unit for this measurement is centimeters of water equivalent per year.

For More Information

http://www.nasa.gov/topics/earth/features/glacier_tech.html

Visualization Credits

Lori Perkins (NASA/GSFC): Lead Animator
Scott Luthcke (NASA/GSFC): Scientist
Gretchen Cook-Anderson (RSIS): Writer
Please give credit for this item to:
NASA/Goddard Space Flight Center Scientific Visualization Studio

Science Paper:
Luthcke, Scott, and others. 'Recent glacier mass changes in the Gulf of Alaska region from GRACE mascon solutions'. Journal of Glaciology, Vol 54 No. 188, December 2008

Short URL to share this page:
https://svs.gsfc.nasa.gov/3522

Mission:
Gravity Recovery and Climate Experiment (GRACE)

Data Used:
Gravity Recovery and Climate Experiment (GRACE)/KBR Horn/K-band Intersatellite Range Rate
JPL, the University of Texas and GeoForschungsZentrum Potsdam
view all stories where this data set is used
Note: While we identify the data sets used in these visualizations, we do not store any further details nor the data sets themselves on our site.

Keywords:
GCMD >> Earth Science >> Cryosphere >> Glaciers/Ice Sheets >> Glacier Mass Balance/Ice Sheet Mass Balance
GCMD >> Earth Science >> Cryosphere >> Glaciers/Ice Sheets >> Glaciers
SVS >> For Educators
SVS >> Hydrosphere >> Ice
NASA Science >> Earth
GCMD >> Earth Science >> Solid Earth >> Geomorphic Landforms/processes >> Glacial Processes

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