DEM

[alzj]

DEAR professors，I want to know the SRTM 1，AW3D 30,ASTER GDEM v3 and ICESat-2 ATL 03 ,what‘s the reference of Vertical Datum and Horizontal Datum above what i mentioned，thanks

[LP DAAC - jwilson]

@alzj The SRTM and ASTER products share the same horizontal datum of WGS84 and vertical datum of EGM96.

For additional documentation, please visit:
https://www.earthdata.nasa.gov/data/catalog/lpcloud-astgtm-003#documents-and-resources
https://www.earthdata.nasa.gov/data/catalog/lpcloud-srtmgl1-003#documents-and-resources
https://lpdaac.usgs.gov/documents/179/SRTM_User_Guide_V3.pdf
https://lpdaac.usgs.gov/documents/642/DEM_Comparison_Guide.pdf

Please let me know if you have any further questions on the SRTM and ASTER data products.
Janice

[NSIDC - fritzdi]

Hello @@alzj ,

WGS-84 for ATL03's datum

For ICESat-2's ATL03 data, you can find this kind of information in the documentation linked on the ATL03 data set landing page: https://nsidc.org/data/atl03/versions/7 (Other data sets also have this information available in this way as well!). From the ATBD: "Each photon event will have been placed within a geodetic coordinate system; the elevations are given in the ITRF2020 reference frame and the geographic coordinates (latitude,longitude, and height) are referenced to the WGS-84 ellipsoid based on the G1150 model (ae =6378137m, 1/f = 298.257223563)."

Please let me know if you have more questions.

Kind regards,
Diane