[MetaCRS] NAD83 and WGS84

[Frank Warmerdam]

Folks,

I have generally treated NAD83 and WGS84 as equivelent for the purposes of
PROJ.4 and this seems to be the general practice in the GIS industry.  I
have a potential client asking about what it would take to add NAD83 to
WGS84 conversions so now I feel obligated to ask if there are established
transformations between them that are meaningful in any sense?

I presume they would be tied to particular realizations of NAD83 or WGS84.
I assume distinguishing realizations is something we are going to have to get
better at over time.  Is that a reasonable statement?

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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and watch the world go round - Rush    | Geospatial Programmer for Rent