Ice, Cloud, and land Elevation Satellite (ICESat) / Geoscience Laser Altimeter System (GLAS) Data, 2003-Ongoing

ICESat (Ice, Cloud, and land Elevation Satellite) is the benchmark Earth Observing System mission for measuring ice sheet mass balance, cloud and aerosol heights, as well as land topography and vegetation characteristics.

The main objective of the ICESat mission is to measure ice sheet elevations and changes in elevation through time. Secondary objectives include measurement of cloud and aerosol height profiles, land elevation and vegetation cover, and sea ice thickness. ICESat will enable scientists to study the Earth's climate and, ultimately, predict how ice sheets and sea level will respond to future climate change.

ICESat was lauched January 12, 2003, on a Boeing Delta II rocket from Vandenberg Airforce Base. The Geoscience Laser Altimeter System (GLAS) is the sole instrument on ICESat. On February 20, 2003, GLAS Laser 1 was activated, but it unexpectedly stopped working after providing 36 days of data. On September 25, 2003, ICESat resumed measurements with the second of its three lasers. NASA will issue a report soon on the reason for the cause of the anomaly affecting the first laser.

The National Snow and Ice Data Center (NSIDC) archives and distributes Level-1 and Level-2 data from the GLAS instrument aboard ICESat. Preliminary versions of all ICESat/GLAS products are available as of October 31, 2003. For information about the calibration and validation phase for preliminary ICESat data, please visit http://www.nsidc.org/data/icesat/prelim.html.