Why do waves come in sets?

Understanding why waves come in sets is essential for surfers.

Why do waves come in sets?

Short answer: In simple terms, waves are created by wind pushing on the surface of the water, causing it to move up and down. This initial push creates a wave, and as the wind continues to blow, it follows and pushes on the wave, creating a set or group of waves.

So while every wave may come in a set, there may be periods where only one wave forms due to changes in wind patterns.

Overall it is more likely for multiple waves to form together as the wind continuously pushes on the water’s surface.

As you learn how to surf, it’s important to understand why waves come in sets so you can read waves and ultimately, catch more waves.

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How many waves are in a set?

The number of waves in a set can vary greatly, as it is determined by a combination of factors such as wind strength and direction, water depth, and coastline features.

However, on average, a set will consist of 10-15 waves.

It’s important to note that waves don’t simply appear out of nowhere – they are created when wind travels over the surface of the water and transfers its energy to create peaks and troughs.

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When this energy builds up and reaches a certain point, it will form a group (or set) of waves that travel in the same direction.

So why do sets exist instead of continuous individual waves?

Sets allow for a more efficient transfer of energy from the wind to the water, allowing for larger and stronger waves overall.

Understanding why sets occur can also help surfers determine when the best time to catch a wave will be.

As each wave in a set loses energy and breaks, the subsequent waves become progressively smaller until the set ends and another begins.

Surfers often wait for breaks between sets to catch their wave, as these tend to have more energy and size.

Is it true that every seventh wave bigger?

Many surfers have experienced the phenomenon of waves coming in sets, with several smaller waves followed by a larger one.

The reason for this is a combination of physics and geography.

In deep water, water molecules move in circular motions to create waves, with the circular motion continuing downward until it hits the ocean floor.

When these circular movements reach shallower water near the shore, they are compressed into a more linear motion, causing the wave to break.

This means that waves will continue to travel in sets as long as their depth and distance from shore remain consistent.

However, why some waves in a set may seem bigger than others is a bit more complex.

Wind, tides, and obstructions such as reefs can all affect the shape and height of individual waves within a set.

So while it’s not always true that every seventh wave will be bigger, it’s safe to expect that there will be variations in size within each set of waves. 

Additionally, it’s important to remember that wave height can also change quickly and unexpectedly, so it’s crucial to always stay alert when swimming or surfing at the beach.