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A vertical datum is a surface of zero elevation to which heights of various points are referenced. Traditionally, vertical datums have used classical survey methods to measure height differences (i.e. geodetic leveling) to best fit the surface of the earth. The current vertical datum for the contiguous United States and Alaska is the North ...
State the vertical datum name and year in that document. Example: "Vertical coordinate information is referenced to the North American Vertical Datum of 1988 (NAVD 88)." If a GNSS survey is used to establish elevations (orthometric heights), the geoid model used to convert ellipsoid heights to orthometric heights should be referenced.
European Datum 1950: SAD69: South American Datum 1969: GRS 80: Geodetic Reference System 1980: ISO 6709: Geographic point coord. 1983: NAD 83: North American Datum 1983: WGS 84: World Geodetic System 1984: NAVD 88: N. American Vertical Datum 1988: ETRS89: European Terrestrial Ref. Sys. 1989: GCJ-02: Chinese obfuscated datum 2002: Geo URI ...
The North American Vertical Datum of 1988 ( NAVD 88) is the vertical control datum of orthometric height established for vertical control surveying in the United States of America based upon the General Adjustment of the North American Datum of 1988. NAVD 88 was established in 1991 by the minimum-constraint adjustment of geodetic leveling ...
European Datum 1950: SAD69: South American Datum 1969: GRS 80: Geodetic Reference System 1980: ISO 6709: Geographic point coord. 1983: NAD 83: North American Datum 1983: WGS 84: World Geodetic System 1984: NAVD 88: N. American Vertical Datum 1988: ETRS89: European Terrestrial Ref. Sys. 1989: GCJ-02: Chinese obfuscated datum 2002: Geo URI ...
Changing these products, both graphic and digital, to the North American Vertical Datum of 1988 will be a massive and costly undertaking and will require a decade or more to complete. This transition will occur as the maps or digital data are revised or updated. Changing the Geological Survey third-order leveling data to the North American ...
Dec 7, 2023 · Datums and Reference Frames. A geodetic datum or reference frame is an abstract coordinate system with a reference surface (such as sea level) that serves to provide known locations to begin surveys and create maps. NGS defines the official geodetic datums for all federal mapping activities in the U.S. and its territories (see Table 1) as part ...
