Correction to ICESat Data Product Surface Elevations

The ICESat Project Science Team announced that a correction to ICESat surface elevation data products is necessary due to an error in the range determination from transmit-pulse reference selection (centroid vs. Gaussian, G-C). The effect of this error of omission varies on a shot-to-shot basis and for the calibration passes over the Salar de Uyuni in Bolivia the campaign-averaged values varied from +/- 6 cm over the mission. Similar results were found when tabulating the track-averaged corrections (G-C) over Antarctica. Note that the track-averaged (G-C) values are fairly constant within a campaign, so any elevation-data adjustments that were made for campaign-level biases that were determined to an independent reference surface using data including the G-C error should eliminate the G-C error from the elevation data on an average basis. For a more detailed explanation, see the full statement below.

The following products are affected by this finding: GLA06 (global elevation), GLA12 (ice sheet), GLA13 (sea ice), and GLA15 (ocean). GLA14 users who use the range increment for the alternative Gaussian-fitted peaks also may want to use the correction.

The ICESat Project will provide correction files to the NSIDC DAAC, which can be applied directly to the surface elevations on a shot-by-shot basis for each of the ICESat laser campaigns.

How to Access Correction Files

NSIDC expects to receive the correction files in February for distribution via FTP.

If you have questions please contact nsidc@nsidc.org.

Visit the NSIDC DAAC News page for more information.