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National Aeronautics and Space Administration

Goddard Space Flight Center


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Polar Ice Altimetry

Polar Ice Altimetry

Antarctica Surface Elevation Map Greenland Surface Elevation Map

5 Km Antarctica and Greenland DEMs from Geosat and ERS-1


The Cryosphere Science Research of the Earch Sciences Division at NASA/GSFC, under the direction of Dr. H. Jay Zwally, with contractor support from SGT, Inc. and SSAI, Inc., has processed satellite radar and aircraft laser altimetry over the continental ice sheets and surrounding sea ice to calculate surface elevations.


04/08/2012 -- ENVISAT mission ended on April 8,2012

04/08/2010 -- Cryosat-2 was launched successfully.

08/31/2000 -- IMPORTANT information for users of ERS-1 and ERS-2 altimetry data regarding:

  • The USO and SPTR corrections: There are two corrections to the ERS-1 and ERS-2 ranges that were applied to the online Greenland and Antarctica data. The first of these is a correction for a drift in the Ultra-Stable Oscillator(USO). The second is the Scanning Point Target Response(SPTR) correction. The characterization of these two corrections can be found on the ESA Earth Observation web site.
  • A 40.9 cm bias that exists bewteen the ERS-1 and ERS-2 altimeter ranges. This correction has also been applied to the ERS Greenland and Antarctica data.