How Is A Wave Formed?
When most of us visit a beach, we see many people surfing there, moving easily with their boards over water. But, have you ever wondered how they are able to do so? How do these waves become so powerful to carry a surfer to such high and long distances in open water? Why is there a separate marked area for surfing, and why is surfing prohibited beyond a certain range?
You can only answer these queries when you know about the basics of wave formation and its associated factors such as what causes waves. So, to resolve all your ambiguities, let's get deep into the anatomy of the formation of a wave.
What is a Wave, and How a Wave Forms?
A wave (the splashes/whirls you see on water) is a disturbance that transfers energy from one place to another. As the wind blows over the ocean, it transfers power to the surface, which causes small ripples in the water to grow into waves. Waves close to their source are large, powerful, and broad in wavelength (distance between two successive crests). The longer a wave travels, the more its energy is spread out.
Factors Contributing to the Size of a Wave:
Anything that is created needs something for its growth and survival, and the same is the case with waves. Waves don't need oxygen like us, but many factors are responsible for the strength of any wave. Three of these factors are very crucial:
Wind Speed
Duration of Blowing Time
Fetch (it's the distance over which the wind blows).
Wind Speed:
You may have seen that on a stormy and windy day, the waves are splashier, noisier, and go higher than the normal days. It clearly shows that wind speed is related to the size of waves.
A gentle breeze can never generate a big wave; only strong winds cause friction on the water surface, which in turn causes waves to form. The stronger the wind, the bigger the wave tends to be.
But how does it happen? The wind speed can vary from 10 mph to over 100 mph and contributes to the size of a wave by increasing the drag on the seawater. As the wind speed increases, the drag has a greater impact on the energy of the molecules, which leads to an increase in wave size.
Duration of Wind Blowing Time:
Waves are not out-of-the-box things; they also work on general principles of Physics. Wind blowing over an area for a certain amount of time affects the size of a wave. Waves are more extensive when the wind blows for a lengthier period since the more energy the wind builds up, the bigger the wave is.
Fetch:
No, it’s not the same word that you use for playing with your pup? Fetch is a term used to describe the horizontal distance over which the wind blows with a sustained speed, and it is an essential factor in determining the size of a wave.
Fetch is not defined by a set reach but by the specific conditions that cause waves to form. As such, fetch lengths can vary across different bodies of water. For example, a wave takes over 1000 kilometers to form in the North Atlantic Ocean, where conditions are ideal for fetch development. In contrast, fetch length is much smaller on small lakes near shore or sheltered bays.
Learning about wave formation can be very helpful in successfully catching a wave.
Types of Waves Suitable for Surfing in the Ocean:
Some waves, like wind swells, may travel distances about 1000 kilometers from their point of origin. Others like shore-breaks form and break over the rocks by the seashore. This clearly shows that not all the waves are good-to-go for surfing. There are certain features that make a wave good for surfing.
As per our detailed research and considering the diversity of waves, we have come to the point that there are four different types of waves suitable for surfing in the ocean. Those four types are groundswell, wind swells, wrap-around, and edge waves. Each of these waves has its unique characteristics.
Groundswell:
A groundswell wave is a very powerful surf wave that can be very dangerous for the inexperienced surfer. Groundswell waves are formed in deep water by strong winds that blow over a body of water for a long period, causing a buildup of large swells. When a groundswell wave reaches the shore, it is termed a shore break.
The best time to surf on a groundswell wave is when it is still small so that it does not break too fast and cause you to lose your balance or fall off your board. This type of surf is best suited for those having an excellent sense of balance since they do not always have to worry about being thrown off if they fall off the board.
Wind Swells:
Wind swells are fast-moving, long-period swells that result from gusts and squalls over a broad fetch of water. They can occur in lakes, oceans, and bays. Since they are short-lived, they are best for surfing when they hit close to shore. It's essential to check the surf report frequently when looking at wind swells to catch them at their best.
Edge Waves:
Edge waves form when two opposing bodies of water collide, such as a lake (freshwater) and an ocean (saltwater). They are also known as shelf waves or interface waves.
Edge waves are great for surfing because they are much faster than other waves. These allow surfers to surf longer distances, which is exciting for them.
Another reason edge waves are excellent for surfing is that they have more power than other waves. The surf wave gives surfers more speed, allowing them to get farther on their boards.
Wrap-Around:
Have you ever seen a surfer moving in a circular pattern and confused it with a man drowning in a whirlpool? Don’t worry because they are surfing (usually).
Wrap-around is a type of surfing move (you can say on a manipulated wave) where the surfer rides the wave in a circular motion. The maneuver was mastered by surfer Mark Richards in 1976 and is considered one of the most challenging tracks to perform during competitions. Surfers who are just starting should not attempt it.
Wrap-around can be challenging as they require the surfer to go beyond their comfort zone. Before attempting a wrap-around, the surfer must be familiar with bottom turns, off-the-lip tricks, and make radical changes in direction without losing speed. Without these skills, a surfboarder can get hurt trying to attempt a wrap-around.
To Conclude:
That’s it! Now you know how waves are formed, facts about waves and which types of waves are good for surfing in the ocean. Now, you can go to the ocean and apply this knowledge. By learning about ocean science, you will get a deeper appreciation of the extraordinary power of nature.