National Geodetic Vertical Datum of 1929
(Redirected from
Sea Level Datum of 1929
)| Geodesy |
|---|
 |
The National Geodetic Vertical Datum of 1929 is the official name since 1973mean sea level (MSL).
NGVD29 was superseded by the
U.S. Army Corps of Engineers "legacy" projects with established data continued to use the older datum.[4]
Methodology
Mean sea level was measured at 26 tide gauges: 21 in the United States and five in
adjustment of observations. The adjustment required a total of 66,315 miles (106,724 km) of levelling
with 246 closed circuits and 25 circuits at sea level.
Since the Sea Level Datum of 1929 was a hybrid model, it was not a pure model of
National Geodetic Survey, a part of the National Oceanic and Atmospheric Administration.[1]
See also
- Altitude
- Elevation
- Geodetic datum
- Geodesy
- Geoid
- Mean sea level
- North American Vertical Datum of 1988
- Reference ellipsoid
- Topography
References
- ^ a b US Department of Commerce, National Oceanic and Atmospheric Administration. "National Geodetic Vertical Datum of 1929 (NGVD 29) - Vertical Datum - Datums - National Geodetic Survey". www.ngs.noaa.gov. Retrieved 2022-02-01.
- ^ .esri.com GIS Dictionary: National Geodetic Vertical Datum of 1929 Accessed November 18, 2023
- ^ US Department of Commerce, National Oceanic and Atmospheric Administration. "North American Vertical Datum of 1988 (NAVD 88) - Vertical Datum - Datums - National Geodetic Survey". www.ngs.noaa.gov. Retrieved 2022-02-01.
- ^ "Standards and Procedures for Referencing Project Elevation Grades to Nationwide Vertical Datums" (PDF).