Each of us is very familiar with the waves that occur at sea in the afternoon and especially in stormy weather. This situation sometimes worries us and causes us to get out of the sea. What about square waves? Why should we worry about them?
Let’s take a closer look at how these unusual square formations occur and where we might encounter them.
Most of the normal waves we know travel parallel and break horizontally, but square waves collide at right angles to form those blocks we see.
Square waves, which are mostly seen in the oceans, are actually quite rare, but it is possible to encounter this image at certain times of the year on the island of “Île de Ré – Isle of Ré” in the Bay of Biscay, France.
These formations, which can reach a height of 3 meters and appear and disappear in an instant, have been seen in the open waters of the South Pacific and Atlantic Ocean until now.
These square waves are pretty easy to spot when the ocean starts to look like a grid pattern, and each wave is broken up by the opposing wave.
While these waves on the Isle of Ré resemble a grid where two waves meet and form squares in the ocean, they pose a number of hazards as they come from two different directions and from two different weather systems. For this reason, they are accompanied by opposing and strong currents.
So what causes these waves?
Actually, there are many answers to this question. Sometimes called “cross waves,” these square waves occur when different waves from different weather systems meet at a right angle.
In areas such as the Isle of Ré where conditions are ideal for cross-waves, it can be consistent and regular, occur spontaneously, and persist for only a few short waves.
Sometimes the air pushes the waves in one direction and the current moves in another direction, and sometimes tropical storms send waves in the opposite direction, causing this square appearance.
Also, wind shears can redirect waves and change their shape by striking waves that have already formed and are continuing in different directions. They can also show themselves when two waves coming from slightly different angles combine to form a more pronounced wave or a larger peak.
The views on the security of these formations are highly controversial.
Although it is sometimes stated that these waves do not pose any danger if they are small, it is generally concluded that they can pose various risks.
This phenomenon is not particularly dangerous for sailors and confident swimmers in shallow waters where currents are not strong, but currents that can pull swimmers out to sea are dangerous in difficult swimming areas.
Although it is sometimes difficult to notice these currents, they can actually be predicted with some signs.
In fact, where square waves would pose a serious risk is offshore, where counter-wave currents and water volumes can accumulate and also cause severe imbalances in ships.
This situation exposes ships and boats to the risk of taking in water and naturally the probability of accident increases. According to the European Space Agency, these square formations were responsible for the majority of shipwrecks from 1995 to 1999.