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In requirements/specifications if WGS84 is indicated, is there a standard way to determine which revision of WGS84 is being referenced? For example, while WGS84 was developed in 1984, the latest revision to it was in 2004.

In my case, what I'm especially concerned about is if there is another revision in the future. What is the standard way for me to indicate that software was designed relative to the 2004 revision of WGS84?

If these revisions are so trivial that it doesn't matter, that is also an acceptable answer. I could not find out what revisions existed between 1984 and 2004 nor what revision exactly was made in 2004.

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Confluence GIS has more, or at different, information than the Wikipedia page you referenced.

The usual convention that I've seen is to include the GPS week when the realization was defined. The current version of WGS 84 is WGS 84 (G1762). Note that Confluence uses "WGS84".

The EPSG Registry added the WGS 84 realizations in January 2016. However, they only added Geocentric (XYZ) and 3D Geographic (lat-lon-ellipsoidal height) version, not 2D Geographic.

Disclosure: Esri employee and EPSG subcommittee member (I help maintain the registry).

  • Thanks for the link, but that source says, "The current realization WGS84 (G1762) follows the criteria outlined in the International Earth Rotation Service (IERS) Technical Note 21 (TN 21). The responsible organization is the National Geospatial-Intelligence Agency (NGA). NGA plans to conduct a WGS84 reference frame network adjustment in 2013 to incorporate IERS Conventions 2010 Technical Note 36 (TN 36)." <-- Note the "plans to conduct a WGS84 reference frame network adjustment in 2013" portion. – Ben Hocking Aug 16 '17 at 22:48
  • (That said, I think the notation answers my question.) – Ben Hocking Aug 16 '17 at 22:48
  • Ah, the 2005.0 dates are the "epoch" dates. G1762 was released in 2013. See this NGA pdf. – mkennedy Aug 16 '17 at 23:05
  • OK, that makes sense, but the language is still confusing, they're using future tense there to refer to the plans in 2013 after G1762 was released. (I guess that was an old sentence that they forgot to remove?) – Ben Hocking Aug 16 '17 at 23:07

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