Recently I watched Lords of Dogtown, and I noticed that surfing has a lot to do with Physics...
Kinetic Energy of Waves:
Oceanic Waves hold a lot of kinetic energy which is transferred to the surfer as they ride - propelling the surfer forward. This kinetic energy in the waves is dependent on the height of the wave (a.k.a. the amplitude of the wave).
The relationship can be written as: Energy = c * Amplitude2 (where c is a constant)
Centripetal Force when Carving:
Surfers turn sharply when they ride a wave and this is called "carving". Also, the coefficient of friction on water is very low. This results in a lot of sliding around. So when surfers "carve" they aren't necessarily changing the vector component of their momentum.
This equation can be modeled as: Fc = (mass*velocity2) / radius of turn
The average surfer has a mass of 65kg, is traveling a speed of 15 m/s, and is turning on a radius of
less than 2 meters... This results in a very high centripetal force.
Transverse Nature of Oceanic Waves:
Ocean waves are a type of transverse wave. Though they do not resemble a normal sine wave... they more resemble a transverse than longitudinal wave. The actual H2O molecules do not move along with the wave but are rather just moving up and down like electrons in a light wave.