Hi, I would suggest to see attach file and following link

http://www.asprs.org/a/publications/proceedings/sanantonio09/Pagnutti.pdf

Hi Saeed,

worked for me with the following steps:

Run NGAT with IDL virtual machine, creates a textfile with:

ID, date, time, Y-coordinate, X-coordinate, elevation, height of geoid, ?, ?. ?. correction of geoid for WGS84

footprint – height of geoid (- correction of geoid for WGS84)

Things to notice:

• GLAS14 averages elevations for footprints of 70 m, only use for larger targets
• Clouds can interfere with the signal: Remove points which are significantly different (>150 m)  from their neighbors or the SRTM

Hey!

If You use ArcGIS the thing is simple.

1. Download the DEM together with the ENVI header (*.hdr)

2. Next in ArcMap use: ArcToolbox - Conversion Tools - From Raster - Raster to Point (this option will extract all DEM's pixels height values to point shapefile - very useful tool)

3. But, if You have Your own set of points and You want to compare height values from two different DEMs exactly in places where these points are located - You can extract height values (for Your set of points) from one DEM and then from another; You have to use in ArMap: ArcToolbox - Spatial Analyst Tools - Extraction - Extract Values to Points.

Good Luck!

Bart

Hello Andreas Braun I checked the ICESat tools page http://nsidc.org/data/icesat/tools.html and the NGAT tool is not listed. Pls can you send me the tool, or pls refer me to another source where I can download it?

Thanks

Chuks

Dear Chukwuma John Okolie : YOu can now download ICESat data directly here:

https://nsidc.org/data/icesat/data.html (select a product (e.g. GLAH14, then open the "Download data" tab)

or even better here: https://openaltimetry.org/