172
5. Tides
a
b
Fig. 5.10: Influence of Coriolis force on particle motion on the rotating Earth:
a particle movement parallel to the Earth's axis, b particle movement normal to the
Earth's axis; solid line denotes initial path of particle, dashed line denotes deflection
of particle path due to Coriolis effect
2
2
UE
wEr =-,
r
in which U E is the tangential velocity of the Earth at point P.
(5.23)
We now assume that the water particle starts to move with the current eastward, with horizontal velocity Up over the Earth's surface. Thus, the new
acceleration of the particle becomes:
r
or:
U~ + 2UEUp + u~
r
(5.24)
(5.25)