What is rip current in the seas and how to get rid of it?

A member of the scientific staff of the National Research Institute of Oceanography and Atmospheric Sciences, while explaining rip currents in the seas and oceans as one of the causes of drowning, identifying areas with the possibility of rip currents, informing beach tourists, installing warning signs and teaching through textbooks to prevent He considered this phenomenon very useful from the casualties.

Summer is not only the season of closing schools and universities, but also the season of travel. This summer also has its enthusiasm; After two years of closures and bans due to the spread of Corona, the number of tourists has increased in different cities. As the registration of more than 52 million overnight stays in the country’s official accommodation centers in Nowruz 1401 confirmed the 63% growth of the stay compared to the previous two years, summer will also record an unprecedented number of tourism. The coastal areas that are spread in the north and south of Iran are considered as one of the popular places for Iranian people to travel, but these trips are not without risks, and according to Saadi: going to the sea has countless benefits, and if you want health, it is on the side.

Rip currents are coastal currents or deadly currents that move from shore to sea and sometimes drown swimmers, even professional swimmers. This current is one of the most important factors in drowning in the seas and the movement of this current starts from inside the coastal ridge area and continues to outside the wave break line. In fact rip currents appear in all seas, lakes and oceans.

Mohammad Hossein Kazeminejad, in an interview with the reporter of IRNA’s Science and Education Department, said about rip currents in the seas and oceans, especially in the sea areas of Iran: Many beaches in the world are categorized as beaches with the potential to create rip currents. This current is one of the most dangerous currents for swimmers that can form near the coasts of oceans, seas and lakes. We see this current on the coasts of Iran, mainly on the coasts of the Caspian Sea and the Oman Sea. Of course, it does not mean that it is not possible to form this flow in other areas. From a scientific point of view, these currents are usually formed in periods of several hours to several days with an average flow speed of about five tenths of meters per second, and they are important in the coastal mixing of heat, pollutants, nutrients and various marine species. Don’t buy life.

Rip currents are important because of the dangers to swimmers. A rip current can quickly carry unsuspecting swimmers with full swimming abilities into deeper water, often leading to drowning due to exhaustion and panic.

The member of the scientific staff of the research institute and the head of the research institute of marine technology and engineering at the National Research Institute of Oceanography and Atmospheric Sciences explained about the scientific reasons for the occurrence of these currents: rip currents have a complex system and in terms of location and possibility of occurrence, they can be transitory, temporary or permanent. be created in an area. In the scientific literature, splitting currents are classified in different ways, and these classifications face difficulties in interpretation and ambiguities.

He clarified: All types of rip currents are controlled by the hydrodynamics of the coastal area and waves. In terms of dominant controlling factors, these flows can be divided into three categories; Splitting currents that are created only by hydrodynamic factors and in the absence of morphological factors, whose occurrence can change in terms of time and space. Splitting currents are caused by hydrodynamic processes that are strongly influenced by natural changes in the morphology of the bed, and splitting currents are caused by hard lateral boundary conditions such as the presence of natural headlands or man-made structures such as piers and breakwaters.

The splitting current of the ocean and seas

Kazmininejad noted: These currents can be created in coastal areas in the presence of waves with low or high height. In conditions where the waves have a low height, this current is weak, and in conditions where the sea is rougher, the intensity of these currents increases. Most of these currents are established in a limited channel with a speed of about five tenths of meters per second from the coast to the sea, and their speed can reach more than 2 meters per second. In this situation, even the strongest swimmer cannot swim against the direction of this current, and if he faces this current, he will drown due to extreme fatigue and fear.

These currents can occur at any time of the year when the sea is rough, but its main danger is during the swimming season for beach tourists, so that this current can be identified as the main cause of most drownings.

Actions of coastal authorities to inform and prevent casualties

A member of the scientific staff of the National Research Institute of Oceanography stated: It is important to identify the areas where the potential for creating a rip current is high or the areas where these stable currents exist in that area. Doing this requires detailed studies and simulations. Of course, it is somewhat impossible to identify all the areas prone to creating splitting currents and to predict the types of splitting currents. However, identifying these areas can help in choosing the areas where swimming is allowed and prohibited. The factor that can have a greater impact in this field is proper information and informing beach tourists about the existence of these currents. One of the reasons people drown is the fear of not knowing.

In some areas of the Caspian Sea, after moving away from the coast, we feel that the depth of the water has decreased. The reason for this is being placed on a sedimentary ridge, and with a little displacement, we may be placed in the channel of the splitting current, and difficult conditions will be created. In this situation, the swimmer is shocked and if he does not have enough knowledge about how to face this current, he tries to swim against the current, which usually leads to drowning.

He emphasized: Adequate information about the existence and nature of these currents and how to escape from these currents plays a key role in saving the lives of swimmers. Notification can be through the media, installing warning signs and educational posters in coastal areas, or printing educational pamphlets and distributing them among beach tourists. Of course, for the long term, education can be planned through the educational content of schools.

What should a swimmer do?

Kazeminejad also said about the proper actions of tourists and people in these situations: When a person is caught in a rip current and suddenly feels that he is being pulled towards the sea by a strong current, he should follow the following steps so that he can get out of this by traveling a distance. flow out:

* The swimmer must keep calm

* Due to the fact that these currents are created almost perpendicular to the coastline and towards the sea, a person who is in the path of this current should never face this current and swim against the direction of the current, i.e. towards the shore. Swimming in the opposite direction of this current greatly increases the possibility of fatigue and drowning of the swimmer

* If the swimmer is in the channel of the splitting current, he should swim slightly in the direction of the current or keep himself afloat and gradually get out of the current path by swimming obliquely.

* If you can’t get out of the rip current by swimming diagonally, move with the current and keep yourself afloat. After some distance the current slows down and you can wade out of the current and then swim back to shore.

* If you notice someone caught in the rip current, only try to help him with a high swimming ability and a life jacket.

In the end, Kazmininejad noted: It is useful to know that the rip current does not take a person under water, and this current is a surface current facing the sea, which is created in a channel almost perpendicular to the coast. As soon as the person trapped in the current channel can overcome his fear and panic, he can get out of this current by following the points mentioned.

He continued: It is recommended to swim in the designated areas where the lifeguards are present. Also pay attention to signs and warnings. Avoid swimming around coastal structures such as breakwaters and other coastal structures because there is a high probability of rip currents in their vicinity.

Rip currents have visual characteristics that we should refrain from swimming in that area if we see them. Usually, when we are on land, by moving away from the coast line and standing on a high ground, evidence of rip currents may be seen, such as in the place where the rip current is created, the water surface usually looks smoother and calmer than the adjacent areas, and a change It is seen in the wave breaking pattern.

A member of the scientific staff of the National Oceanographic Research Institute noted: the surface of the rip current usually looks foamy; Because the rip current moves the foam on the water surface from the shore to the sea. In the area of ​​the rip current, the color of the water may be different from the surrounding water, and depending on the angle of the sun, the color of the water can be darker or lighter than the surrounding water. Sometimes it is observed that in the boundary of the rip current, the bottom on the water or the floating debris moves from the shore to the sea, while in the vicinity of it, the floating objects or the bottom on the water are pushed towards the shore.