What Causes Waves

Wind generated waves, informally referred to as ocean surface waves or simply waves, are waves which occur on the surface of various water bodies. These waves may range from ripples, caused on the surface of the lake, to gigantic roller coasters. Though their name itself suggests that the driving force behind these waves is wind, there exist a few other factors which play a crucial role in development of waves on the surface of any water body.

What Causes Waves in the Ocean?

In order to understand that, you will have to do a small experiment. Take a shallow pan, and fill it with water to the brim. Now stay one side of the pan, and start blowing your breath into it. You will see the formation of small 'waves' on the surface of the water in the pan. The same process goes into formation of oceanic waves. The only difference is that the power of actual wind is much more than the power of your blowing into the pan, due to which the waves in the ocean are bigger in size, than the tiny ripples which form in your pan.

The most prominent factors involved in the formation of waves on a water body include wind speed, depth of the water, fetch (i.e. the distance covered by the wind) etc. Waves come in various shapes and sizes. The size of the wave depends on the velocity of the wind. The faster the wind is blowing, the bigger will be the waves. This is the reason the waves which form during a storm, wherein wind speed is quite high, are bigger than the waves we see daily.

The wind speed, in turn, depends on the distance covered by the wind and the open area on which the wind is blowing. More the distance is covered, more will be the power of the wind. Similarly, ocean surface being an open area, there are hardly any obstructions to resist and decrease the velocity of the wind. Both these factors play an equally crucial role in causing waves on the surface of the ocean.

Though the wind is the major factor when it comes to wave formation, earthquake is yet another factor which causes waves that are a lot bigger and far more devastating when compared to wind waves. Earthquakes occurring on the ocean floor have the propensity to trigger gigantic waves capable of sweeping across the coastal areas with immense ease. These waves are mainly caused as a result of movement of tectonic plates beneath the ocean floor. When one tectonic plate, encroaches upon another, it gives rise to a sudden gust of water, which picks up speed as it travels and culminates onto the land, in form of gigantic waves referred to as Tsunamis.

What Causes the Waves to Break?

Like the formation of waves, breaking of waves is also equally interesting. Most of us are familiar with the phenomena wherein waves break as they near the shoreline, but not many of us are aware of the fact that waves tend to break in the mid-oceans as well. There are two factors which can cause a wave to break - shallowness of the water body and contrasting wave patterns.

Waves which break as they near the shoreline actually break due to shallowness of water. As the wave approaches the land, the rising ground tends to give it a upward push making the crest go higher and higher, until it reaches the maximum possible height and finally gives up and break. Waves which break in the mid ocean actually break, as a result of collision with the another wave coming in from a different direction. No two waves are the same, nor are their directions. In such circumstances, when two waves come face to face with each other and collide, it causes both of them to break.

Refraction occurs when a wave comes in contact with the shore, in such a manner that the part of the wave, at the forefront, touches the ground and slows down, while the remaining part continues to move at the same speed, thus causing the wave to bend. Now that you are well versed with the basics of different types of waves, the next time you go to some beach, you are bound to experience a different kind of joy in watching those beautiful waves cruising their way into the land.