my physics is a little rusty, but i do remember that, as a wave enters the shallower water near shore, its wavelengh decreases, height increases and speed decreases, as it encounters the resistence of the bottom.
Waves are caused by tide, wind and atmospheric pressure systems as well as earthquakes, volcanic disturbances and landslides. As waves move closer to shallow water hey break up as they interact with with the ocean floor. Wave speed is influenced and changed by depth of water. It's more commonly known as wave dispersion.
What kind of answer are you looking for with this?
I have a BS in Oceanography and have spent more than enough time in "Waves and Tides" courses dealing on the theory side and actual math side.
Let me know what you are looking for and I can provide.