Figure B 1.  World Geodetic System 1984 Reference Frame

Z(WGS 84) = Z(NSWC 9Z 2) + 4.5 meters

(2)

S(WGS 84) = S(NSWC 9Z 2)   0.6 ppm

(3)

l(WGS 84) = l(NSWC 9Z 2) + 0.814"

(4)

In the above relationships, Equations 2 4 refer to the Z axis bias, scale correction, and

longitudinal bias in the definition of the prime meridian, respectively, and the WGS 84, thus

achieved, is coincident with the BIH defined CTS

1

.

Origin = Earth s center of mass.

Z Axis = Parallel to the direction of the Conventional Terrestrial Pole (CTP) for

polar motion, as defined by the Bureau International de L Heure (BIH) on the basis

of the coordinates adopted for the BIH stations.

X Axis = Intersection of the WGS 84 Reference Meridian Plane and the plane of

the CTP s Equator, the Reference  Meridian being parallel to the Zero Meridian

defined by the BIH on the basis of the coordinates adopted for the BIH stations.

Y Axis = Completes a right handed, ECEF orthogonal coordinate system, measured

in the plane of the CTP Equator, 90 degrees East of the X Axis.

B 2