Name: GLAS/ICESat L1B Global Elevation Data (HDF5), Version 33
Creator: National Snow and Ice Data Center
Keywords: GLACIER ELEVATION/ICE SHEET ELEVATION,GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY,ICE ROUGHNESS,ICE SHEETS,REFLECTANCE,SEA SURFACE HEIGHT,SEA SURFACE SLOPE,SURFACE ROUGHNESS,TERRAIN ELEVATION

GLAS/ICESat L1B Global Elevation Data (HDF5), Version 33

Data set id:

GLAH06

DOI: 10.5067/ICESAT/GLAS/DATA106

Data Citation and Acknowledgment
As a condition of using these data, you must cite the use of this data set. Such a practice gives credit to data set producers and advances principles of transparency and reproducibility.

Zwally, H. J., Schutz, R., Dimarzio, J. & Hancock, D. (2012). GLAS/ICESat L1B Global Elevation Data (HDF5). (GLAH06, Version 33). [Data Set]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. https://doi.org/10.5067/ICESAT/GLAS/DATA106. [describe subset used if applicable]. Date Accessed 09-24-2025.

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Other standard citation formats may be found on the DOI Citation Formatter website (paste 10.5067/ICESAT/GLAS/DATA106 into the top form field).

Describing subset: When applicable, include the information a reader would need to extract the same subset at the end of your citation. If multiple or complex steps were incolved, it may be more appropriate to include this information in the paper itself.

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There is a more recent version of these data.
Version Summary

For information about Version 33, visit the ICESat/GLAS Version History page: https://nsidc.org/data/icesat/version-history

Overview

GLAH06 Level-1B Global Elevation is a product that is analogous to the geodetic data records distributed for radar altimetry missions. It contains elevations previously corrected for tides, atmospheric delays, and surface characteristics within the footprint. Elevation is calculated using the ice sheet parameterization. Additional information allows the user to calculate an elevation based on land, sea ice, or ocean algorithms. Each data granule has an associated browse product.

Parameter(s):

GLACIER ELEVATION/ICE SHEET ELEVATION

GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY

ICE ROUGHNESS

ICE SHEETS

REFLECTANCE

SEA SURFACE HEIGHT

SEA SURFACE SLOPE

SURFACE ROUGHNESS

TERRAIN ELEVATION

Platform(s):

ICESAT

Sensor(s):

GLAS

Data Format(s):

HDF

Temporal Coverage:

20 February 2003 to 11 October 2009

Temporal Resolution:

Not Specified

Spatial Resolution:

Not Specified

Spatial Reference System(s):

Not Specified

Spatial Coverage:

N:
86
S:
-86
E:
180
W:
-180

Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.

View Metadata Record

Data Access & Tools

This data set has been retired. There is a more recent version of these data.

Documentation

User Guide

GLAS/ICESat L1 and L2 Global Altimetry Data (HDF5), Version 33, 34 User Guide

General Resources

GLAS Altimetry HDF5 Product Usage Guide

ICESat/GLAS Surface-Type Mask

Help Articles

General Questions & FAQs

Are the altimetry data adjusted to the Geoid, or only to the Ellipsoid?

The ICESat/GLAS elevation data are relative to the ellipsoid. The data also have a parameter indicating the geoid height, which is the height of the EGM2008 geoid above the TOPEX/Poseidon ellipsoid for the first and last shot in the record:

This article covers frequently asked questions about the NASA NSIDC DAAC's Earthdata cloud migration project and what it means to data users.

Analysis of altimetric data acquired by the GLAS instrument requires accurate determination of the laser spot location on the Earth's surface (ice, land, water, clouds) or geolocation of the laser spot.

Yes, it is an element of GLAH06, GLAH12, GLAH13, GLAH14, and GLAH15.

Surface roughness greatly affects the elevation measurement accuracy. Over most of the ice sheets, the accuracy of each elevation measurement is 15 cm.

The standard waveform fit is optimized for "ice sheet-like" returns. The majority of these are single-peaked, narrow waveforms. The standard fit allows for only two peaks. Alternate waveform fitting is meant to capture up to six peaks.

The NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) is migrating its primary data access from its legacy, on-premises archive to the NASA Earthdata Cloud.

Several parameters help quantify the shape of the GLAS laser footprint, which change slightly for each campaign. These parameters are:

How to Articles

Filter and order from a data set web page using the Data Access Tool

Many NSIDC DAAC data sets can be accessed using NSIDC DAAC's Data Access Tool. This tool provides the ability to search and filter data with spatial and temporal constraints using a map-based interface.Users have the option to:

To convert HDF5 files into binary format you will need to use the h5dump utility, which is part of the HDF5 distribution available from the HDF Group. How you install HDF5 depends on your operating system.

The instructions below will describe how to extract elevation in text format from GLAS HDF5 Altimetry data using the free open source tool HDFView.

The HDF Group has example code for access and visualization of MODIS, GLAS HDF5, AMSR-E, and NISE data in MATLAB, IDL, Python, and NCL.

Learn the basic steps for using OpenAltimetry to browse and download ICESat data.

NASA Earthdata Cloud Data Access Guide

The NASA Earthdata Cloud is the NASA cloud-based archive of Earth observations. It is hosted by Amazon Web Services (AWS). Learn how to find and access NSIDC DAAC data directly in the cloud.

This article highlights the NSIDC DAAC data sets available with customization options and outlines a workflow for searching, ordering, and customizing data in NASA Earthdata Search. This approach is ideal for users who want to download data to their local machine.

HDFView https://support.hdfgroup.org/products/java/hdfview/ When you first open HDFView, the HDFView window appears with an empty tree and data panel.