What causes waves?
Water waves are caused mainly by the wind. On a windy or stormy day there are many waves in the water, and on a calm day there are fewer waves.
This explains what makes most waves in the water. Winds push up waves on seas, lakes and ponds. The waves you see on a calm day were started far away. Somewhere over the ocean winds blew against the water and set it in motion.
When you watch the waves, the water seems to move forward. But the water does not actually move forward in a wave at all. A water wave is mostly the up-and-down motion of the water. This may be compared to the waves made in a rope by shaking one end of it. The waves un the length of the rope, but the rope does not move forward.
When the wave motion of the water reaches the shoreline, the shallow bottom makes the water spill onto the beach. Sometimes an earthquake or an undersea volcano causes a great, destructive wave to seep in from the ocean like a huge tide. Most people call these tidal waves. Scientist call them “tsunami” (su NA me), Japanese word that means “storm wave”.