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Earthdata Search: NASA's newest search and order tool for subsetting, reprojecting, and reformatting data.
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NOTE: Reverb will be decommissioned in the coming months and replaced with Earthdata Search. All links to Reverb will be removed at that time.
GLAS Subsetter: Order geographic and temporal subsets of the data.
Data Set ID:
GLA02

GLAS/ICESat L1A Global Atmosphere Data, Version 33

The Geoscience Laser Altimeter System (GLAS) instrument on the Ice, Cloud, and Land Elevation Satellite (ICESat) provides global measurements of polar ice sheet elevation to discern changes in ice volume (mass balance) over time. Secondary objectives of GLAS are to measure sea ice roughness and thickness, cloud and atmospheric properties, land topography, vegetation canopy heights, ocean surface topography, and surface reflectivity.

GLAS has a 1064 nm laser channel for surface altimetry and dense cloud heights, and a 532 nm lidar channel for the vertical distribution of clouds and aerosols.

Level-1A atmospheric data (GLA02) include the normalized relative backscatter for the 532 nm and 1064 nm channels, and low-level instrument corrections such as laser energy (1064 nm and 532 nm), photon coincidence (532 nm), and detector gain correction (1064 nm).

Each data granule has an associated browse product that users can quickly view to determine the general quality of the data in the granule. Browse products consist of image plots of key parameters and statistics. Data are in scaled integer binary format, big-endian (Unix) byte order, and are available via FTP.

Version Summary:

For information about Version 33, see the NSIDC ICESat Description of Data Releases page.

Geographic Coverage

Spatial Coverage:
  • N: 86, S: -86, E: 180, W: -180

Spatial Resolution:
  • 60 m to 70 m x 60 m to 70 m
Temporal Coverage:
  • 20 February 2003 to 11 October 2009
Temporal Resolution: 3 hour
Parameter(s):
  • Infrared Wavelengths > Sensor Counts
  • Visible Wavelengths > Sensor Counts
Platform(s) ICESAT
Sensor(s): ALTIMETERS, GLAS
Data Format(s):
  • Binary
Version: V33
Data Contributor(s): H. Zwally, Robert Schutz, Steve Palm, William Hart, Dennis Hlavka, James Spinhirne, Ellsworth Welton

Data Citation

As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.

Zwally, H. J., R. Schutz, W. Hart, D. Hlavka, S. Palm, J. Spinhirne, and E. Welton. 2011. GLAS/ICESat L1A Global Atmosphere Data, Version 33. [Indicate subset used]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. doi: http://dx.doi.org/10.5067/ICESAT/GLAS/DATA122. [Date Accessed].
No technical references available for this data set.

FAQ

Why is spatial searching not enabled for GLA01 (GLAH01) to GLA04 (GLAH04)?

The orbit for GLA01 (GLAH01) and GLA02 (GLAH02) is a predicted orbit and does not show any target-of-opportunity pointing. The GLAS science team decided not to enable spatial searching for these two products in... read more