[Federal Register Volume 60, Number 157 (Tuesday, August 15, 1995)]
[Notices]
[Page 42146]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-19408]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[Docket No. 950728196-5196-01]
Use of the ``NAD 83/GWS 84'' Datum Tag on Mapping Products
AGENCY: Office of National Geodetic Survey, National Ocean Service,
National Oceanic and Atmospheric Administration, Commerce.
ACTION: Notice.
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SUMMARY: The Office of National Geodetic Survey, redefined and
readjusted the North American Datum of 1927 (NAD 27), creating the
North American Datum of 1983 (NAD 83). The World Geodetic System of
1984 (WGS 84) was defined by the Defense Mapping Agency (DMA). The
interagency Federal Geodetic Control Subcommittee (FGCS) at its meeting
on December 7, 1994, recommended that ``All maps and charts produced
for North America, at scales of 1:5,000 or smaller, that are based on
either the North American Datum of 1983 (NAD 83) or the World Geodetic
System of 1984 (WGS 84), should have the horizontal datum labeled as
NAD 83/WGS 84''.
SUPPLEMENTARY INFORMATION: The following supplementary information was
reviewed by FGCS membership. A Federal Register notice published on
June 29, 1979 (44 FR 37969), by the National Oceanic and Atmospheric
Administration (NOAA) provided notification of the establishment of a
new Datum (NAD 83) to which the geographic and plane coordinate values
for the National Network of Horizontal Geodetic Control would be
referenced. A Federal Register notice published on June 14, 1989 (54 FR
25318), by NOAA affirmed NAD 83 as the official horizontal datum for
all future U.S. surveying and mapping activities performed or financed
by the Federal Government. Furthermore, this notice said that to the
extent practicable and feasible, all Federal agencies using coordinate
information should provide for an orderly transition to NAD 83.
Both NAD 83 and WGS 84 were originally defined (in words) to be
geocentric and oriented as the Bureau International de l'Heure (BIH)
Terrestrial System. In principle, the three-dimensional coordinates of
a single physical point should therefore be the same in both NAD 83 and
WGS 84 systems; in practice, small differences are sometimes found. The
original intent was that both systems would use the Geodetic Reference
System of 1980 (GRS 80) as a reference ellipsoid. As it happened, the
WGS 84 ellipsoid differs very slightly from GRS 80. The difference is
0.0001 meters in the semi-minor axis.
Effective January 2, 1994, the WGS 84 reference system was
realigned to be compatible with the International Earth Rotation
Service's Terrestrial Reference Frame (ITRF).
FOR FURTHER INFORMATION CONTACT: Mr. James E. Stem, N/CG11, SSMC3
Station 9357, National Geodetic Survey, NOAA, Silver Spring, Maryland
20910; telephone: (301) 713-3231, FAX: (301) 713-4176, Internet:
jstem@ngs.noaa.gov.
Dated: July 5, 1995.
W. Stanley Wilson,
Assistant Administrator, NOS.
[FR Doc. 95-19408 Filed 8-14-95; 8:45 am]
BILLING CODE 3510-08-M
