WGS84RPT.tif:Corel PHOTO-PAINT - Henry A. Rowland Department ...

f = flattening of the local geodetic datum ellipsoid
∆a, ∆f = differences between the semi-major axis and flattening of the
local geodetic datum ellipsoid and the WGS 84 Ellipsoid,
respectively (WGS 84 minus Local)
e = first eccentricity
e 2 = 2f – f 2
R N = radius of curvature in the prime vertical
R N = a/(l- e 2 sin 2 φ) 1/2
R M = radius of curvature in the meridian
R M = a(l- e 2 )/(l- e 2 sin 2 φ) 3/2
NOTE: All ∆-quantities are formed by subtracting local geodetic datum ellipsoid values from
WGS 84 Ellipsoid values.
Appendix A lists the reference ellipsoid names and parameters (semi-major axis
and flattening) for local datums currently tied to WGS 84 and used for generating datum
transformations.
Appendix B contains horizontal transformation parameters for the geodetic
datums/systems which have been generated from satellite ties to the local geodetic control.
Due to the errors and distortion that affect most local geodetic datums, use of mean datum
shifts (∆X, ∆Y, ∆Z) in the Standard Molodensky datum transformation formulas may produce
results with poor quality of “fit”. Improved fit between the local datum and WGS 84 may
result only with better and more dense ties with local or regional control points.
Updates to the datum transformation parameters are identified through the use
of cycle numbers and issue dates. Cycle numbers have been set to the numerical value of zero
for all datum transformations appearing in the August 1993 Insert 1 and the WGS 84
TR8350.2 Second Edition. All new datum transformations will carry a cycle number of zero.
As updates are made the cycle number will increment by one.
Datum transformation shifts derived from non-satellite information are listed in
Appendix C.
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