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Shortcomings of Newton’s Equilibrium Tidal Theory

Observations of tidal records show departure from Equilibrium Tidal Theory. Not all locations exhibit semidiurnal tides with ranges and timing attributable to predicted tidal constituents.

Complexities Addressed by Dynamic Tidal Theory Oceans are shallow. Continents get in the way of tidally-driven water motions. Earth is spinning, hence there is a Coriolis effect. Equilibrium Tidal Theory assumes that water has no inertia.

Dynamic Tidal Theory – Shallow Oceans How fast should the tidal wave move across the open ocean? Across the continental shelf?

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Dynamic Tidal Theory – Effect of Inertia/Resonance

Pierre-Simon Laplace

Standing tidal wave oscillates about a nodal line Natural period of oscillation depends on basin geometry Tidal waves are forced waves, not free waves

~15 m tidal range at Minas Basin 3 m tidal range at bay mouth why? 1. Basin geometry results in resonance 2. Embayment where convergence of water occurs

Bay of Fundy, Nova Scotia

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(3) Water (and air) flowing toward poles moving faster than ground;

appears to deflect to right

(4) Opposite in S. hemisphere

(1) Earth rotating eastward

(2) Faster velocity near equator

Dynamic Tidal Theory – Coriolis Effect

http://www.gly.uga.edu/railsback/Tides/TideTank03.html

Coriolis Effect - Amphidromic Points

Counter Clockwise Rotation of the Kelvin wave about the Amphidromic Point. Co-tidal lines and Co-range lines.

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Global Distribution of Amphidromic Points

Dynamic Tidal Theory – Shallow Oceans Tidal Wave Movement and Tidal Bores

1.  blackboard calculation

2.  Tidal bore of the Kampar River in Indonesia. This is one of the two major tidal bores in Indonesia: the Rokan and the Kampar:

http://www.youtube.com/watch?v=2_vmS-bCoNU&feature=player_embedded