Naming Convention

NGS, in cooperation with the Canadian Geodetic Survey, has finalized certain key decisions in the replacement of the three NAD 83 reference frames, and in the replacement of the various vertical datums of the NSRS.

Four Terrestrial Reference Frames

Replacing the three existing NAD 83 reference frames will be four plate-fixed terrestrial reference frames. The tectonic plate for each frame may be inferred from their names, which are:

• North American Terrestrial Reference Frame of 2022 (NATRF2022)
• Pacific Terrestrial Reference Frame of 2022 (PATRF2022)
• Mariana Terrestrial Reference Frame of 2022 (MATRF2022)
• Caribbean Terrestrial Reference Frame of 2022 (CATRF2022)

Each of the four frames will be identical to ITRF2020 at epoch 2020.00. Away from that epoch, the four frames will relate to ITRF2020 through the definition of an Euler pole rotation specific to that plate. However, since no tectonic plate is perfectly rigid, a simple Euler pole rotation model will not capture all of the horizontal motions (and none of the vertical motions) that a geodetic control mark might be undergoing. As such, all such residual motions will be captured in a 3-D deformation model called the intra-frame deformation model of 2022, or IFDM2022

Heights and Other Physical Coordinates

A geopotential datum will be created that will contain all of the necessary information to provide mutually consistent orthometric heights, geoid undulations, gravity anomalies, deflections of the vertical, and all other geodetic coordinates related to the gravity field. This geopotential datum will be called North American-Pacific Geopotential Datum of 2022 (NAPGD2022).

Geoid Model

Within NAPGD2022, a variety of products will exist. The most prominent of these products will be a time-dependent model of the geoid, provided in three regions (the first covering the entirety of North and Central America, Hawaii, Alaska, Greenland, and the Caribbean; the second covering American Samoa; and the third covering Guam and the Commonwealth of the Mariana Islands). The name of this model will be GEOID2022.