rogue waves

Photograph of a large wave approaching a merchant ship. Circa 1940s

rogue waves (Rogue waves, monster waves, white wave , English rogue wave- wave-robber, freak-wave- wave-moron, scumbag; fr. onde accelerate- wave-villain, galejade- bad joke, hoax) - giant single waves that arise in the ocean, 20-30 (and sometimes more) meters high, and have behavior uncharacteristic of sea waves. Real “killer waves” that pose a danger to ships and offshore structures: the structures of a ship that encounters such a wave may not withstand the enormous pressure of the water falling on it (up to 980 kPa, 9.7 atm), and the ship will sink in a matter of minutes.

An important circumstance that allows us to distinguish the phenomenon of rogue waves into a separate scientific and practical topic, and to separate it from other phenomena associated with waves of anomalously large amplitude (for example, a tsunami), is the appearance of “rogue waves” out of nowhere. Unlike tsunamis, which arise as a result of underwater earthquakes or landslides and gain great height only in shallow water, the appearance of “rogue waves” is not associated with catastrophic geophysical events. These waves can appear in low winds and relatively weak waves, which leads to the idea that the phenomenon of “rogue waves” itself is associated with the dynamics of sea waves themselves and their transformation as they propagate in the ocean.

For a long time, wandering waves were considered a fiction, since they did not fit into any mathematical model of the occurrence and behavior of sea waves (from the point of view of classical oceanology, waves with a height of more than 20.7 meters cannot exist in the Earth’s oceans), and also there were not enough reliable evidence. However, on January 1, 1995, on the Dropner oil platform in the North Sea off the coast of Norway, a wave 25.6 meters high, called the Dropner wave, was first recorded by instruments. Further research as part of the MaxWave project, which involved monitoring the surface of the world's oceans using the European Space Agency's (ESA) ERS-1 and ERS-2 radar satellites, recorded more than 10 single giant waves in three weeks around the globe. , whose height exceeded 25 meters. These studies force a new look at the causes of the death of ships of such size as container ships and supertankers over the past two decades, including rogue waves as possible causes.

The new project is called Wave Atlas and provides for the compilation of a worldwide atlas of observed rogue waves and its statistical processing.

Causes

Perhaps the reason for the appearance of giant single waves is the movement of a high front at a certain speed. atmospheric pressure in the direction of the low pressure zone (expansion of the high pressure zone), as described in the work of V. N. Shumilov. With such an “advance” of a high pressure front, a phenomenon occurs almost analogous to the surge of water into the shallow eastern part of the Baltic Sea, when the water level in the Neva in St. Petersburg rises by several meters.

Another possible reason are called interference maxima when waves of different directions propagating in the water column overlap. The most probable zones of wave formation in this case are called the zones of sea currents, since in them the waves caused by the heterogeneity of the current and the unevenness of the bottom are the most constant and intense.

Another reason for the occurrence of such waves may be the difference in energy potentials different layers water, which under certain circumstances is “discharged”, as in the atmosphere during a thunderstorm or tornado. The upper layer of water, saturated with oxygen, accumulates a positive electrical potential, and the deep layers containing dissolved methane, low-valent oxides of iron, manganese, etc., accumulate negative; under certain conditions, this energy can cause disturbances and the movement of large masses of water. A ship, submarine, some object, a lightning strike, a splash or something else can simply close the contacts in the circuit and start the “wave engine”, and it can work both “in suction”, with a suction funnel, and in pushing a mass of water to the surface.

Interestingly, such waves can be both crests and troughs, which is confirmed by eyewitnesses. Further research involves the effects of nonlinearity in wind waves, which can lead to the formation of small groups of waves (packets) or individual waves (solitons) that can travel long distances without significantly changing their structure. Similar packages have also been observed many times in practice. The characteristic features of such groups of waves, confirming this theory, are that they move independently of other waves and have a small width (less than 1 km), with heights decreasing sharply at the edges.

Numerical modeling of rogue waves

Direct modeling of rogue waves was undertaken in the works of V. E. Zakharov, V. I. Dyachenko, R. V. Shamin. Equations describing the unsteady flow of an ideal fluid with a free surface were solved numerically. Using a special type of equations, it was possible to carry out calculations with great accuracy and over long time intervals. In the course of numerical experiments, characteristic profiles for rogue waves were obtained, which are in good agreement with experimental data.

In the course of a large series of computational experiments on modeling the dynamics of surface waves of an ideal fluid with physical parameters characteristic of the ocean, empirical functions of the frequencies of rogue waves were constructed depending on the steepness (~energy) and dispersion of the initial data.

Experimental observation

One of the problems in studying rogue waves is the difficulty of obtaining them in laboratory conditions. Researchers are mainly forced to work with data obtained from observations in natural conditions, and such data are very limited due to the unpredictable nature of the rogue wave.

In 2010, Peregrine breather solitons were experimentally obtained for the first time, which, according to many scientists, are a possible prototype of rogue waves. These solitons, which are a particular solution of the nonlinear Schrödinger equation, were obtained for an optical system, but already in 2011 the same solitons were obtained for water waves. In 2012, in another experiment, scientists were able to experimentally demonstrate the generation of a higher-order breather soliton, for which the amplitude is five times greater than the amplitude of the background wave.

Known cases

• In April 1966, the Italian transatlantic liner Michelangelo was struck by a white wave in the mid-Atlantic, washing two passengers out to sea and injuring 50. The ship received serious damage to the bow and one of the sides.

• In September 1995, the British transatlantic liner Queen Elizabeth 2 in the North Atlantic during Hurricane Louis tried to “ride” a 29-meter wave that appeared directly ahead.

Rogue waves in art

• In the 2006 film Poseidon, the passenger liner Poseidon, traveling to Atlantic Ocean V New Year's Eve. The wave turned the ship upside down, and a few hours later it sank.
• Ridley Scott's film "White Squall" tells the story of the death of a training ship from a sudden squall followed by the emergence of a huge wave.
• “The Perfect Storm” is an adventure drama based on real events that occurred during Hurricane Grace on the American coast.

Notes

Links

• Pelinovsky E. N., Slyunyaev A. V. “Freaks” - killer sea waves // Nature, No. 3, 2007.
• S. Badulin, A. Ivanov, A. Ostrovsky. The influence of giant waves on the safety of offshore production and transportation of hydrocarbons
• Kurkin A. A., Pelinovsky E. N. “Rogue waves: facts, theory and modeling”, Nizhny Novgorod. state those. univ. N. Novgorod, 2004.

Wikimedia Foundation. 2010.

See what “Rogue Waves” are in other dictionaries:

Continuum mechanics Continuum Classical mechanics ... Wikipedia

Continuum mechanics ... Wikipedia

Killer waves (Rogue waves, monster waves) are giant single waves 20-30 (and sometimes more) meters high, arising in the ocean and exhibiting behavior uncharacteristic of sea waves. They should not be confused with tsunamis that occur in... ... Wikipedia

This term has other meanings, see Wave (meanings). A wave is a change in the state of a medium or physical field (disturbance), propagating or oscillating in space and time or in phase space. In other words... ... Wikipedia

Waves on the water are caused primarily by wind. On a pond, mirror-smooth in calm weather, when the wind blows, ripples appear; on the lake there are waves. There are places in the ocean where the height of wind waves reaches 30-40 m. This is explained by the fact that in a shallow pond the close bottom dampens water vibrations. And only in the vast expanses of the ocean can the wind seriously disturb the surface of the water.

However, even huge waves are not always scary. After all, the water in a wave does not run in the direction of the wind, but only moves up and down. More precisely, it moves in a small circle inside the wave. Only in strong winds do the tops of the waves, picked up by the wind, move ahead of the rest of the wave, causing collapse - then whitecaps appear on the waves.


It seems to us that a wave is running across the sea. In fact, the water inside the wave moves in a small circle. Near the shore, the lower part of the wave touches the bottom, and the neat circle is destroyed.

A wave can cause serious damage to a tall ship, especially a sailing ship whose mast height is much greater than the height of the sides. Such a ship is like a man being pushed under the knee. The raft is a different matter. It protrudes quite a bit above the water, and tipping it over is like turning over a mattress lying on the floor.

When a sea wave approaches the shore, where the depth gradually decreases, its lower part is slowed down by the bottom. At the same time, the wave rises upward, and collapses appear even on the most modest waves. Its upper part collapses onto the shore and immediately goes back along the bottom, continuing its circular motion. That’s why it’s so difficult to go ashore even with slight waves.


Waves near the shore can become destructive.

On steep rocky shores, the wave does not gradually slow down on the bottom, but immediately brings down all its power onto the shore. That is probably why the waves near the shore are called surf.
While the surface of the lake may be smooth, the ocean is covered with waves almost constantly. The fact is that in a huge ocean there is always a place where wind waves form. And it is rare to find land that can stop these waves. The highest wind waves on the planet occur in the 40-50 latitudes of the Southern Hemisphere. There's a constant blow there westerly winds and there is almost no land to slow down the waves.


Such a storm is caused by wind waves (fragment of I.K. Aivazovsky’s painting “Wave”).

An earthquake or volcanic eruption shakes the surface of the sea not as often as the wind, but much more powerfully. Sometimes this creates powerful waves that travel at speeds of hundreds of meters per second. They can travel around the Pacific Ocean, and sometimes the entire Earth, before they begin to fade. They are called tsunamis. The height of a tsunami in the open ocean is only 1-2 m. But the wavelength (the distance between the crests) is large. Therefore, it turns out that each wave carries a huge mass of water moving at colossal speed. When such a wave approaches the shore, it sometimes grows up to 50 m. There is little that can resist a tsunami on the shore. Humanity has still not come up with anything better than evacuating residents of coastal areas to the interior of the mainland.

Sea roughness is the fluctuation of the water surface up and down from the average level. However, they do not move horizontally during waves. You can verify this by observing the behavior of a float swinging on the waves.

Waves are characterized by the following elements: the lowest part of the wave is called the base, and the highest is called the crest. The steepness of a slope is the angle between its slope and the horizontal plane. The vertical distance between the base and the crest is the height of the wave. It can reach 14-25 meters. The distance between two troughs or two crests is called the wavelength. The longest length is about 250 m; waves up to 500 m are extremely rare. The speed of wave movement is characterized by their speed, i.e. the distance covered by the comb usually in a second.

The main reason for wave formation is. At low speeds, ripples appear - a system of small uniform waves. They appear with every gust of wind and instantly fade away. With a very strong wind turning into a storm, the waves can be deformed, with the leeward slope being steeper than the windward one, and with very strong winds the crests of the wave break off and form white foam - “lambs”. When the storm ends, high waves continue to travel across the sea for a long time, but without sharp crests. Long and gentle waves after the wind stops are called swell. A large swell with low steepness and a wave length of up to 300-400 meters in the complete absence of wind is called a wind swell.

The transformation of waves also occurs as they approach the shore. When approaching a gently sloping shore, the lower part of the oncoming wave is slowed down by the ground; the length decreases and the height increases. Top part the waves move faster than the bottom. The wave overturns, and its crest, falling, crumbles into small, air-saturated, foamy splashes. The waves, breaking up near the shore, form a surf. It is always parallel to the shore. The water splashed onto the shore slowly flows back down the beach.

When a wave approaches a steep shore, it hits the rocks with all its force. In this case, the wave throws up in the form of a beautiful, foamy shaft, reaching a height of 30-60 meters. Depending on the shape of the rocks and the direction of the waves, the shaft is broken into parts. The impact force of the waves reaches 30 tons per 1 m2. But it should be noted that the main role is played not by the mechanical impacts of masses of water on the rocks, but by the resulting air bubbles and hydraulic changes, which mainly destroy the composing rocks (see Abrasion).

Waves actively destroy coastal land, roll over and abrade debris, and then distribute it along the underwater slope. Near the inland coastline, the impact force of the waves is very high. Sometimes at some distance from the shore there is a shoal in the form of an underwater spit. In this case, the breaking of waves occurs on the shallows, and a breaker is formed.

The shape of the wave changes all the time, giving the impression of running. This is due to the fact that each water particle uniform movement describes circles around the equilibrium level. All these particles move in one direction. At each moment the particles are at different points of the circle; this is the wave system.

The largest wind waves were observed in the Southern Hemisphere, where the ocean is most extensive and where westerly winds are most constant and strong. Here the waves reach 25 meters in height and 400 meters in length. Their movement speed is about 20 m/s. In the seas the waves are smaller - even in the big ones they reach only 5 m.

A 9-point scale is used to assess the degree of sea roughness. It can be used when studying any body of water.

9-point scale for assessing the degree of sea state

To protect port facilities, piers, and coastal areas of the sea from waves, breakwaters are built from stone and concrete blocks to absorb wave energy.

It is known that waves are a product of winds. They arise due to the fact that air currents interact with the upper layers of the water column, moving them. Depending on the wind speed, the wave can travel over vast distances. As a rule, due to a decrease in the level of kinetic energy, waves do not have time to reach land. The weaker the wind currents, the correspondingly smaller the wave.

The emergence of waves occurs naturally. Here everything depends on the wind: its speed, the area covered. Typically, the attitude maximum value The height of the wave is related to its width as 7:1. Thus, a medium-strength hurricane can generate waves up to twenty meters high. Such waves look stunning: they foam and make a monstrous sound as they move. Watching this giant wave is like watching a horror movie with special effects.

In the 33rd year of the last century, the sailors of the Ramapo ship recorded the largest ocean wave. Its height was thirty-four meters! Waves of this height are called “killers”, as they can easily swallow huge ships. Scientists believe that given value wave heights are not the limit. Theoretically, the maximum possible wave height is sixty meters.

In addition to winds, the cause of waves can be landslides, volcanic eruptions, earthquakes, meteorite falls, and nuclear bomb explosions. The high power pulse generates a wave called a tsunami. These waves are characterized by a long length. The distance between tsunami crests can be tens of kilometers. In view of this, the height of such waves in the ocean is, at most, a meter. At the same time, the speed indicators are shocking: tsunamis can travel eight hundred kilometers in one hour. Due to length compression as a tsunami approaches land, the wave height increases. Therefore, near the coastline the tsunami height is several times greater than the size of large wind waves.

Tsunamis can also occur due to tectonic displacements and faults in the ocean floor. At the same time, millions of tons of water begin to move sharply, moving at the speed of a jet plane. Such tsunamis are discouraging: while moving towards the coastline, the wave gains gigantic heights, and then covers the ground with a wall of water, absorbing everything with its power. The scale of such a disaster is difficult to underestimate: a tsunami could easily destroy an entire city.

The greatest likelihood of experiencing the harmful effects of a tsunami occurs in bays that have a fairly high shore. Such places are real traps for giant waves. They are capable of attracting tsunamis without any warning. From the shore it can be seen as if what is happening is the rising tide of the sea (or low tide). In extreme cases, you might think that a storm is coming. But within a few minutes a wave of indescribable proportions can engulf a vast area. Naturally, such a suddenness of the tsunami does not allow people to evacuate. Today there are very few places in the world where you can find a tsunami warning service. Therefore, as a rule, huge waves entail thousands of deaths and colossal destruction of land. You can remember the tsunami that occurred in 2004 in Thailand: it was a real disaster.\

In addition to bays with high shores, risk zones include areas where increased seismic activity is observed. Japanese islands are places that are constantly attacked by waves different sizes. In 2011, a wave of forty meters high was found on the coast of one of the islands (Japan, Honshu). Then the tsunami caused an earthquake, which was the strongest in Japan ever. The earthquake and tsunami that year claimed the lives of fifteen thousand people. Many are considered missing: they were carried away by the wave.

This tsunami disaster is not the only one in Japanese history. In the eighteenth century (1741), a volcanic eruption occurred, resulting in a huge wave. The height of this tsunami was ninety meters. Then, in 2004, due to an earthquake in the Indian Ocean, Japanese island Java, as well as Sumatra, were attacked by a giant wave. That year, the tsunami took the lives of three hundred thousand inhabitants. It was the largest tsunami in the world (in terms of the number of lives lost).

In 1958, a tsunami struck Lituya Bay, which is located in Alaska. A wave whose height was five hundred twenty-four meters was recorded here. A huge landslide became an impulse, a push for the emergence of this monstrous wave, which moved at a speed of more than one hundred and fifty kilometers per hour.

Tsunamis are the largest and most powerful ocean waves that sweep away everything in their path with terrifying force. The peculiarity of such a dangerous natural disaster is the size of the moving wave, its enormous speed, the gigantic distance between the crests, which reaches tens of kilometers. Tsunamis pose an extreme danger to the coastal zone. Approaching the shore, the wave gains enormous speed, contracts in front of the obstacle, grows significantly in size and deals a crushing and irreparable blow to the land area.

What causes this huge influx of water, which leaves even the tallest and fortified structures no chance of survival? What natural forces can create a water tornado and deprive cities and regions of the right to survive? The movement of tectonic plates and splits in the earth's crust are the worst harbingers of the collapse of a giant stream.

The largest tsunami in the world in the history of mankind

What is the known largest wave in the world? Let's look through the pages of history. The date July 9, 1958 is well remembered by Alaskans. It was this day that became fatal for the Lituya fjord, which is located in the northeastern part of the Gulf of Alaska. The harbinger of the historical event was an earthquake, the strength of which, according to measurements, was equal to 9.1 points. This is what caused the terrifying rockfall, which caused the collapse of rocks and a wave of unprecedented magnitude.

The weather was clear and sunny all day on July 9th. The water level dropped by 1.5 meters, fishermen on ships were fishing (Lituya Bay has always been a favorite place for avid fishermen). Towards evening, around 22:00 local time, a landslide that rolled into the water from a height of 910 meters, followed by huge stones and blocks of ice. Total weight mass amounted to approximately 300 million cubic meters. The northern part of the Lituya Bay was completely flooded with water. At the same time, a gigantic pile of stones was thrown onto the opposite side, resulting in the destruction of the entire green area of ​​the Fairweather coast.

A landslide of this magnitude provoked the appearance of a huge wave, the height of which was 524 meters! This is approximately a building of 200 floors! It was the largest and highest wave in the world. The gigantic force of the ocean water literally washed away Lituya Bay. The tidal wave picked up speed (by this time it had already accelerated to 160 km/h) and rushed towards Cenotaph Island. Terrible landslides simultaneously descended from the mountains to the water, carrying a column of dust and stones. The wave rose to such a size that the foot of the mountain disappeared under it.

Trees and greenery covering the mountain slopes were uprooted and sucked into the water column. The tsunami continually rushed from side to side inside the bay, covering the points of the shallows and sweeping away the forest covers of the high northern mountains on its way. There is no trace left of the La Gaussi spit, which separated the waters of the bay and Gilbert Bay. After everything had calmed down, on the shore one could see catastrophic cracks in the ground, severe destruction and rubble. The buildings erected by the fishermen were completely destroyed. The scale of the disaster was impossible to assess.

This wave claimed the lives of about three hundred thousand people. Only the longboat managed to escape, which by some incredible miracle was thrown out of the bay and thrown over the sandbank. Once on the other side of the mountain, the fishermen were left without a vessel, but were rescued two hours later. The bodies of the fishermen of another longboat were carried away into the abyss of water. They were never found.

Another terrible tragedy

Terrible destruction remained after the tsunami on December 26, 2004 for residents of the Indian Ocean coast. A powerful shock in the ocean caused a disastrous wave. In depth Pacific Ocean, near the island of Sumatra, a fracture of the earth's crust occurred, which provoked a displacement of the bottom over a distance of more than 1000 kilometers. The largest wave that has ever covered the coast was formed from this fault. At first its height was no more than 60 centimeters. But it accelerated, and now a 20-meter shaft was rushing at an insane, unprecedented speed of 800 kilometers per hour towards the islands of Sumatra and Thailand to the east of India and Sri Lanka - to the west! In eight hours, a terrible tsunami, unprecedented in history, flew over the entire coast of the Indian Ocean, and in 24 hours, the entire World Ocean!

The greatest destruction occurred on the shores of Indonesia. The tidal wave buried cities and regions tens of kilometers deep. The islands of Thailand have become a mass grave for tens of thousands of people. Residents of coastal areas had no chance of salvation, since the water blanket held the cities under it for more than 15 minutes. Huge loss of life resulted from natural disaster. Economic losses were also impossible to calculate. More than 5 million residents were forced to leave their homes, more than one million needed help, and two million people needed new housing. International organizations responded and helped the victims in every possible way.

Disaster in Prince William Sound

Strong, irreparable losses caused by an earthquake on March 27, 1964 in Prince William Sound (Alaska) measuring 9.2 on the Richter scale. It covered a huge area of ​​800,000 square kilometers. Such a powerful shock from a depth of more than 20 kilometers can be compared with a simultaneous explosion of 12 thousand atomic bombs! The western coast of the United States of America was significantly damaged, which was literally covered by a huge tsunami. The wave reached as far as Antarctica and Japan. Villages and towns, enterprises, and the city of Veldez were wiped off the face of the earth.

The wave swept away everything that came in its way: dams, concrete blocks, houses, buildings, ships in the port. The wave height reached 67 meters! This, of course, is not the largest wave in the world, but it brought a lot of destruction. Fortunately, the deadly stream claimed the lives of approximately 150 people. The number of victims could have been much higher, but due to the sparse population of these places, only 150 local residents died. Considering the area and gigantic power of the stream, they had no chance of survival.

Great East Japan Earthquake

One can only imagine what force of nature destroyed the shores of Japan and brought irreparable losses to its inhabitants. After this disaster, the consequences will be felt for many years. At the junction of the world's two largest lithospheric plates, an earthquake measuring 9.0 on the Richter scale occurred, about twice the magnitude of the tremors caused by the 2004 Indian Ocean earthquake. A tragic event of enormous scale is also called the “Great East Japan Earthquake.” In just 20 minutes, a terrifying wave, the height of which exceeded 40 meters, reached the shores of Japan, where a large number of of people.

About 25 thousand people became victims of the tsunami. This was the largest wave in the history of the Easterners. But this was only the beginning of the disaster. The scale of the tragedy grew every hour after the attack by the powerful flow of the Fokushima-1 nuclear power plant. The power plant system went out of operating mode due to tremors and shock waves. The failure was followed by a meltdown of the reactors in the power units. Today, a zone within a radius of tens of kilometers is a zone of exclusion and disaster. About 400 thousand buildings and structures were destroyed, bridges were destroyed, railways, highways, airports, ports and shipping stations. It will take years to rebuild the country after the terrible disaster brought by the highest wave.

Disaster on the coast of Papua New Guinea

Another disaster befell the coast of Papua - New Guinea in July 1998. The earthquake, measuring 7.1 on the measurement scale, triggered by a massive landslide, caused a wave more than 15 meters high, which killed more than 200 thousand people, leaving thousands more homeless on the island. Before the invasion of ocean water, there was a small bay here called Varupu, the waters of which washed two islands, where the Varupu people lived, worked and traded peacefully. Two powerful and unexpected impulses from underground occurred within 30 minutes of each other.

They set in motion a huge shaft, which caused strong waves that swept away several villages along a length of 30 kilometers from the face of New Guinea. Residents of seven more settlements needed medical care and were hospitalized. The sea level in the capital of New Guinea, Rabaul, rose by 6 centimeters. A tidal wave of such magnitude has never been observed before, although in this region local residents often suffer from disasters such as tsunamis and earthquakes. A giant wave destroyed and carried under water an area of ​​more than 100 square kilometers to a depth of 4 meters.

Tsunami in the Philippines

Exactly until August 16, 1976, the small island of Mindanao existed in the oceanic depression of Cotabato. It was the most southern, picturesque and exotic place among all the islands of the Philippines. Local residents could not at all predict that terrible earthquake with a power of 8 on the Richter scale will destroy this stunning place, washed by the seas on all sides. A huge force created a tsunami as a result of an earthquake.

The wave seemed to cut off the entire coastline of Mindanao. Not having time to escape, 5 thousand people died under the shelter of sea water. Approximately 2.5 thousand residents of the island were not found, 9.5 thousand received varying degrees of injury, more than 90 thousand lost their shelter and remained on the street. This was the strongest activity in the history of the Philippine Islands. Scientists who examined the details of the disaster found that the power of such a natural phenomenon caused movements of the water mass, which provoked a shift in the islands of Sulawesi and Borneo. It was the worst and most destructive event in the entire period of the existence of the island of Mindanao.