Tidal Theory

Are the results of the gravitational and centrifugal influences of the Sun-Earth-Moon system on bodies of water upon the Earth's surface.

Diurnal Tides- 1 High Water and 1 Low Water tide per day

Semi-Diurnal Tide- 2 High Water and 2 Low Water tides per day

Mixed Tides- A tide which is intermediate between predominantly diurnal and predominantly semi-diurnal tides.

The predictable relationships of the sun & moons motions are used to identify the mathematical components of the tide-raising force. The tide generated by this force is called the equilibrium tide.

It assumes a frictionless sea of uniform depth with out land masses.

• The tide we actually experience and observe.
• It is generated by the forces which make up the equilibrium tide, but is modified by various natural phenomena.

• Natural Resonance of water body
• Friction
• Land Masses
• Shallow Water
• Coriolis Effect
• Weather

Is the horizontal movement which accompanies the rise and fall of the tide.

Is any horizontal movement of the sea that is not caused by the tide.

They are caused by prevailing winds and water masses of different salinities or temperatures.