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Which version of NAD83 is assumed in geographic transformation?

Question asked by fbiles on Jan 7, 2016
Latest reply on Jan 13, 2016 by Dan_Patterson

I have some points in NAD83 (1986).  In fact, A LOT of our GIS data is in NAD83 (1986). I am using Desktop ArcMap v 10.2.2.3552. I want to transform the points to ITRF00.

 

If I choose: WGS_1984_(ITRF00)_To_NAD_1983 + ITRF_2000_To_WGS_1984 for the geographic transformation method, which flavor of NAD83 is being assumed?  Everything I found suggests that NAD83 (CORS96) is being assumed.  If that is the case, how does one transform between NAD83 (1986) to ITRF00? To ITRF08? (Or the most current version of WGS84?). The GIS data covers southeast Alaska.

 

From what I have read, it looks like depending on what version of ArcMap one is using, the name "NAD83" could refer to completely different versions of NAD83. For example, in earlier versions of ArcMap, the transformation NAD_1983_To_WGS_1984_5 assumed that coordinates were in NAD83 (1986), but in current versions of ArcMap (10.x) NAD_1983_To_WGS_1984_5 assumes that coordinates are in NAD83 (CORS96).  Is that correct?  If so it would be VERY HELPFUL if datum names/labels always had their "version" attached.  Does WGS84 in that transformation refer to the original WGS84 or WGS84(G1674), or?

Is there a comprehensive "cheat sheet" that crosswalks ArcMap versions with the datum versions assumed for all datum and geographic transformation names that involve NAD83, WGS84, ITRF reference frames?

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