Tides. If you live near the coast or have ever visited the beach, you are probably aware of tides. But did you know that tides are really big waves that move through the ocean in response to the forces exerted by the Moon and the Sun? Tides start in the ocean and move towards the coast, where they appear as the regular rise and fall of the sea surface. How much the water level changes over the day varies depending on where you are and what day it is.
