Let's talk about the Black Sea waves. The frequent recurrence of strong winds, the significant size of the sea, great depths, and the weak indentation of the coastline contribute to the development of waves. The highest wave heights in the Black Sea are 14 meters. The length of such waves is 200 meters. On the approaches to Sochi, the maximum wave height is 6 meters, the length is 120 meters.
It is possible to evaluate the excitement not only by the elements of the waves (height, length, period), but also by the degree.

Evaluation of the degree of excitement is made on a special scale. So, for example, on this scale, 1 point - the height of the waves does not exceed 25 centimeters, 2 points - the height of the waves 25-75 centimeters, 3 points - 0.75-1.25 meters, 4 points - 1.25-2 meters. In total, the scale has 9 points. It is possible to describe the state of the sea surface during wind waves: 1 point - the appearance of ripples during gusts of wind, 2 points - transparent vitreous foam appears on the crests of the waves, 3 points - separate white "lambs" appear on the crests of the waves, 4 points - the whole sea is covered with "lambs " etc.

The scale of wind strength (where the correspondence of points and meters per second is given) has 12 points. The strength of the storm is determined by the strength of the wind. Therefore, the expression "storm 10 points" will be correct, but the expression "10 points excitement" is incorrect. In the Black Sea, the frequency of strong waves is low. During the most "stormy" year, a wave of 6-9 points is not observed for more than 17 days.

A distinctive feature of the Black Sea waves is their "stability". This is the so-called swell, which has a longer period of oscillation than the wind wave. A swell is a wave observed with little or no wind ("dead swell"). However, the origin of these waves is associated with the activity of the wind. Waves formed in the storm zone, which is located at this time in the western part of the Black Sea, may come to the Caucasian coast of the sea. Near the Caucasian shores, the winds can be weak, and the wave can be large. This will be the swell. The existence of a swell is associated with the concept of the “ninth wave”, which has long been common among our sailors, known to many from the painting by Aivazovsky. It cannot be said that the idea of ​​the ninth wave was completely without any foundation. The fact is that swell waves, as a rule, go in groups, and in the center of the group there are the largest waves, and at the edges of the wave of a smaller height. Some wave of this group can really be much larger than the others, but it is not known which wave it will be in a row - the third, fifth or ninth, and with which wave to start the count. Thus, one should not think at all that it is the ninth wave that is the most terrible. By the way, among the ancient Greeks, every third shaft was considered the most dangerous, and among the Romans - the tenth.

Sailors endure swell more easily than the Azov or Caspian wind wave - "bumpy" with a period of 3-5 seconds. However, the swell has the unpleasant feature that it gives a strong surf near the shore. The wave, almost imperceptible in the sea due to its small steepness, falls on the shore with tremendous force.

Stormy sea video on the Black Sea (Anapa)

Swimming in the sea during a storm is very dangerous. It is usually quite difficult to overcome the zone of breakers and get into the open sea, where you can float relatively calmly, rising and falling with each wave. It is much more difficult for a tired person to get ashore again through a barrier of crumbling and foaming waves. Every now and then he is carried back to the sea. There were cases when even people who knew how to swim well drowned here. That is why on city and sanatorium beaches they hang out signs with warning inscriptions during a storm. It is appropriate to recall here that all animals, jellyfish, sea fleas and other organisms leave the dangerous surf zone before the storm, seagulls fly ashore, however, you can see how some people choose the time of the storm in order to demonstrate their “bravery” by swinging on waves.

The force of the waves hitting the shores and structures is enormous. Near Sochi, it exceeds 100 tons per square meter. During such impacts, bursts with a height of several tens of meters occur. The colossal energy of breaking waves is spent on crushing rocks and moving sediments. Without the influence of waves, the rivers would gradually roll down to the depth, while the waves return them to the coast and force them to move along it. For example, along the Caucasian coast of the Black Sea there is a constant flow of sediment. From Tuapse to Pitsunda, waves move 30-35 thousand cubic meters of sediment per year.

Where there is a beach, the waves lose most of their energy. Where there is none, they destroy the bedrock. During the Great Patriotic War, the erosion of the coast south of the port of Sochi reached 4 meters per year. Immediately after the end of the war, bank protection works were started in this area, and the erosion of the coast stopped.

A railway runs along the Caucasian coast of the sea. Sanatoriums, theaters, maritime stations and residential buildings were built in the coastal zone. Therefore, the sea coast must be protected from erosion. The best protection in this regard is the beach, where the waves break before reaching the shore. To fix the beaches, groins and underwater breakwaters are being built. These structures prevent the movement of pebbles along the coast to other areas and its withdrawal into the depths of the sea. This is how the beach grows.

Are there tsunami waves in the Black Sea caused by earthquakes, as we have in the Far East? There are tsunamis, but they are very weak. They are recorded only by devices and are not even felt by a person.

To what depth do ordinary waves propagate? Already at a depth of 10 meters they are smaller than on the surface, and at a depth of 50 meters they are completely invisible. Maybe in the depths reigns peace, which nothing disturbs? No, it's not. There are their own, so-called internal waves. They differ from surface ones in their size (tens of meters in height and kilometers in length), and the reasons for their origin are different. They arise, as a rule, at the interface between two layers with different densities. Although they are not visible on the surface, submarines face great difficulties during such an “underwater storm”.

It seems to be a banal question, but there are some interesting nuances.

Waves arise for various reasons: due to the wind, the passage of a ship, the fall of an object into the water, the attraction of the moon, an earthquake, an eruption of an underwater volcano or a landslide. But if they are caused by liquid displacement from a passing ship or a falling object, the attraction of the Moon and the Sun contributes to the appearance of tidal waves, and an earthquake can cause a tsunami, it is more difficult with wind.

Here's how it goes...

Here the matter is in the movement of air - there are chaotic whirlwinds in it, small at the surface and large in the distance. When they pass over a reservoir, the pressure decreases, and a bulge forms on its surface. The wind begins to push harder on its windward slope, which leads to a pressure difference, and because of it, the air movement begins to "pump" energy into the wave. In this case, the speed of the wave is proportional to its length, that is, the longer the length, the greater the speed. Wave height and wave length are related. Therefore, when the wind accelerates the wave, its speed increases, therefore, the length and height increase. True, the closer the wave speed is to the wind speed, the less energy the wind can give to the wave. If their speeds are equal, the wind does not transfer energy to the wave at all.

Now let's look at how waves form in general. Two physical mechanisms are responsible for their formation: gravity and surface tension. When some of the water rises, gravity tries to bring it back, and when it goes down, it displaces neighboring particles, which also try to come back. The force of surface tension does not care which way the surface of the liquid is bent, it acts in any case. As a result, water particles oscillate like a pendulum. Neighboring areas are “infected” from them, and a surface traveling wave arises.

Wave energy is well transmitted only in the direction in which the particles can move freely. It is easier to do this on the surface than at depth. This is because the air does not create any restrictions, while at a depth the water particles are in very cramped conditions. The reason is poor compressibility. Because of it, the waves can travel long distances on the surface, but decay very quickly in depth.

It is important that during the wave the fluid particles almost do not move. At great depths, the trajectory of their movement has the shape of a circle, at shallow depths - an elongated horizontal ellipse. Thanks to this, ships in the harbor, birds or pieces of wood sway on the waves without actually moving on the surface.

A special type of surface waves are the so-called killer waves - giant solitary waves. Why they occur is still unknown. They are rare in nature and cannot be simulated in the laboratory. However, most scientists believe that killer waves are formed due to a sharp decrease in pressure over the surface of the sea or ocean. But a more thorough study of them lies ahead.

Here we are in detail

The wind itself can be seen on weather forecast maps: these are low pressure zones. The greater their concentration, the stronger the wind will be. Small (capillary) waves initially move in the direction the wind is blowing.

The stronger and longer the wind blows, the greater its effect on the surface of the water. Over time, the waves begin to increase in size.

The wind has a greater effect on small waves than on a calm surface of the water.

The size of a wave depends on the speed of the wind that forms it. Wind blowing at some constant speed will be able to generate a wave of comparable size. And once a wave reaches the size that the wind can put into it, it becomes "fully formed."

The generated waves have different wave speeds and periods. (More details in the article) Waves with a long period move faster and cover greater distances than their slower counterparts. As they move away from the wind source (propagation), the waves form lines of swells, which inevitably roll onto the shore. Most likely, you are familiar with the concept of a set of waves!

Waves that are no longer affected by the wind are called ground waves (ground swell)? This is exactly what surfers are looking for!

What affects the size of a swell?

There are three main factors that affect the size of waves on the high seas.
Wind speed The larger it is, the larger the wave will be.
wind duration- similar to the previous one.
Fetch(wind coverage area) - again, the larger the coverage area, the larger the wave is formed.

As soon as the influence of the wind on them stops, the waves begin to lose their energy. They will move until the moment when the protrusions of the seabed or other obstacles in their path (a large island for example) absorb all the energy.

There are several factors that affect the size of a wave at a particular location. Among them:

Swell direction- will it allow the swell to get to the place we need?
ocean floor- Swell, moving from the depths of the ocean to the underwater ridge of rocks, forms large waves with barrels inside. A shallow ledge opposite will slow down the waves and cause them to lose energy.
Tidal cycle- some sports are completely dependent on it.

Find out how the best waves come about.

In this article we will talk about where the waves come from and what they are. After all, waves are a unique natural phenomenon that gives surfers a lot of emotions and sensations, forcing them to give up a lot. Surfing is waves. And good surfing is impossible without knowing how waves are born, what affects their speed, strength and shape, as well as without understanding that each wave is different from the other.

Where do ocean waves come from

It's all about the swell. If not for the swell, there would be no waves. What is a swell? Swell is the energy of the wind transferred to the waves. There are several types of swells, wind and bottom (groundswell, reel):

1. As the name suggests, a wind swell is formed due to the wind. Such a swell occurs when the wind blows right next to the coast (for example, during a storm) and creates a chop (chaotic unrest on the surface of the ocean). The wind swell is not very suitable for surfing.
2. Swell, due to which surf waves form on the ocean coast, is called bottom swell. This is exactly where the waves that interest surfers come from.

How a swell is born

Far away in the ocean, a storm is raging with strong winds. These winds start a wave on the water. The stronger the wind, the larger the wave. A certain wind speed corresponds to a very specific wave size. It works like a sail and allows the wind to disperse itself and do more.

When the waves reach their maximum possible sizes, they begin to travel to the far shores in the direction where the wind blows. After a while, the waves become similar to each other - the larger ones absorb the small ones, and the fast ones eat the slow ones. The resulting group of waves, approximately the same size and the same power, is called a swell. A swell can travel hundreds or even thousands of kilometers before it reaches the coastline.

As the swell approaches shallower depths, the lower water flows collide with the bottom, slow down and have nowhere to go but move up, pushing all the water above them. When the water can no longer support its own weight, it begins to collapse. Actually, that's where the waves come from, on which you can surf.

1. Closeouts (close-out) are closed along the entire length in whole sections. Not the best option for skiing unless you are learning to ski in foam. When the size of the waves is more than 2 meters, then such waves can be dangerous. Closeouts can be recognized by the width of the wave peak, which can reach several meters.
2. Spilling waves they slowly approach the shore and, thanks to the slight slope of the bottom, slowly begin to break, without forming a sharp wall and pipe. Such waves need to be paddled in advance, and are more suitable for beginner surfers and longboarders.
3. Plunging waves. Fast, powerful, sharp waves that form a tube. Occurs when a swell encounters an obstacle in its path. For example, it may be a protruding reef or a stone slab. We are used to seeing such waves in surf photos and surf videos. They allow you to make passages in the pipe and airs (jumps). Dangerous for beginner surfers.

Types of surf spots

The nature of the wave is determined by the place where it rises, which place is called the surf spot. Surf spots are divided into several types.

1. Beach break: the swell comes to the beach with a sandy bottom and the wave, having collided with the alluvium of sand at the bottom, begins to break. The peculiarity of beach breaks is that the peaks rise in places where sand alluvium is formed, and their shape and position can change every day, depending on the wind, underwater currents, tide movements and other factors.
   With a change in the shape and size of the alluvium, the characteristics of the waves also change, that is, the waves can be either sharp trumpeting or gentle. The sandy bottom is not particularly dangerous, so beach breaks are great for learning to surf. In Bali, beach breaks are the entire beach along Kuta, Legian and Seminyak, as well as Brava Beach, Eco Beach and others.
2. Reef break.This type of surf spot is characterized by the presence of a reef at the bottom. As a reef, both coral reefs and a stone bottom in the form of individual stones or whole slabs can act. The shape, power and wavelength depend on the shape of the reef at the bottom of the ocean. On a spot with a reef break, you can always predict where the wave will peak. Reef breaks are much more dangerous than beach breaks due to sharp reefs and rocks on the bottom.In Bali, most of the surf spots are reef breaks. Uluwatu, Balangan, Padang-Padang, Batu Bolong and many others.
3. Point break- is when the vell collides with some kind of barrier protruding from the shore. It can be a stone ridge, a cape, a small peninsula. After the collision, the waves go around this obstacle and begin to break one after another. In such places, waves of the most correct form rise, go one after another, and can give you very, very long passages.An example of a point break in Bali is the Medewi spot.

Wind and water

In addition to location and swell, where the waves come from for surfing is also affected by the wind and the height of the water (tides).

Where do waves come from for riding or "gone with the wind"
The quality of the waves depends on the wind on the shore. The most correct wind for surfing is its absence. That is why surfers get up at 4 am or earlier to get to the spot before dawn, when the wind has not had time to wake up, and the water is still mirror-smooth (glassy).

If the wind is still blowing, then the waves will not be spoiled (and sometimes even better) if it is directed from the coast to the ocean. This wind is called offshore. Offshore keeps the waves from breaking, making them sharper.

The wind that blows from the ocean to the shore is called onshore. He breaks the waves, forcing them to close ahead of time, blowing off the peaks. The least preferred wind of all. A strong onshore can generally kill the entire gurney.

Also, the wind can blow along the coast, it is called crossshore. Here much depends on its strength and direction. Sometimes a crossshore can slightly spoil the waves, and sometimes it can act as negatively as an onshore.

Ebb and flow
About tides and how they affect waves, you can read in this article.

wave anatomy

In the structure of the wave, several elements are distinguished:
Wall (face/wall) The section of the wave where the surfer spends most of his time.
Lip (lip)- falling crest of a wave.
shoulder- a place where the wave gradually disappears.
Outsole (trough)- the bottom of the wave.
Pipe (tube/barrel)- a place where water surrounds the surfer from all sides.

Now you know where the waves come from, but theory is theory, and you can truly know the waves only in the process of surfing. The more you watch the waves and ride them, the better you will read the ocean, and this will allow you to catch more and more great waves. And now the board under the armpit and run to ride! 🙂