----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
OLOAD 3 7051 273555 -.00378 +.00378 10. 10.
----+----0----+----0----+----0----+----0----+----0----+----0----+----0----+----0
COLUMNS FORMAT DESCRIPTION DEFAULT VALUE & UNITS
1-6 A6 OLOAD - Requests application and/or
adjustment of ocean loading using the
expanded tide model.
7 I1 If > 0, print oload corrections to 0
station height. [NOTE 1]
8 I1 Direction specification. 3
1 - East, 2 - North, 3 - Vertical
11-14 I4 Site Number. 0
18-24 I7 Doodson number. 0
25-44 D20.8 "A" coefficient. 0.0 M
45-59 D15.3 "B" coefficient. 0.0 M
60-72 D13.1 Sigma "A". 0.0
73-80 D8.2 Sigma "B". 0.0
NOTES:
[1] Ocean loading station height changes printed on unit 96.
[2] Project Merit Standards (USNO Circular NO. 167) gives
phases and amplitudes for various sites in the radial
direction. The Merit model for height displacement due
to the ith constiuent is:
h(i)=amp(i) * cos(arg(i,t)-phase(i))
(note that the phase is subtracted from the
time varying argument).
MAY 1995
9505.0
GLOBAL SET
OLOAD (cont)
NOTES: (continued)
[3] GEODYN uses the following formula:
h(i)=A(i) * cos(arg(i,t)) + B(i) * sin(arg(i,t))
If the Merit convention of phase and amplitude is taken
(with the phase being subtracted), then GEODYN's A and
B coefficients relate to phase and amplitude as follows:
A(i) =+amp(i) * cos(phase(i))
B(i) =+amp(i) * sin(phase(i))
[4] The argument, arg(i,t), is a linear combination of
certain astronomical angles. The linear combination
can be deduced from the input Doodson number.
However, in an effort to be consistent with Merit
standards, certain Doodson numbers which correspond
to diurnal frequencies have a phase added to the
angle directly implied by the Doodson number.
Here is a list of the Doodson numbers for which that
is true:
Darwinian Symbol Doodson # Phase (degrees)
---------------- --------- ---------------
K1 165555 270
O1 145555 90
P1 163555 90
Q1 135655 90
Note that the Q1 tide is not listed by the Merit standards as
having the extra +90. The Merit subroutine does add in +90
for the Q1 tide.
UNITS: KM =Kilometers; M =Meters ; S =Seconds ; Kg =Kilograms
DEG=Degrees ; RAD=Radians ; AS =Arc seconds; MAS=Milli-arc seconds
IF CARD OMITTED: Ocean loading will not be used.
NOV 1994
9411.0
GLOBAL SET