Freak wave - AbsoluteAstronomy.com

Rogue waves are relatively large and spontaneous ocean surface wave

Ocean surface wave

In fluid dynamics, wind waves or, more precisely, wind-generated waves are surface waves that occur on the free surface of oceans, seas, lakes, rivers, and canals or even on small puddles and ponds. They usually result from the wind blowing over a vast enough stretch of fluid surface. Waves in the...

s that occur far out in sea, and are a threat even to large ships and ocean liner

Ocean liner

An ocean liner is a ship designed to transport people from one seaport to another along regular long-distance maritime routes according to a schedule. Liners may also carry cargo or mail, and may sometimes be used for other purposes .Cargo vessels running to a schedule are sometimes referred to as...

s. In oceanography

Oceanography

Oceanography , also called oceanology or marine science, is the branch of Earth science that studies the ocean...

, they are more precisely defined as waves whose height

Wave height

In fluid dynamics, the wave height of a surface wave is the difference between the elevations of a crest and a neighbouring trough. Wave height is a term used by mariners, as well as in coastal, ocean and naval engineering....

is more than twice the significant wave height

Significant wave height

In physical oceanography, the significant wave height is defined traditionally as the mean wave height of the highest third of the waves , but now usually defined as four times the standard deviation of the surface elevation...

(SWH), which is itself defined as the mean of the largest third of waves in a wave record. Therefore rogue waves are not necessarily the biggest waves found at sea; they are, rather, surprisingly large waves for a given sea state

Sea state

In oceanography, a sea state is the general condition of the free surface on a large body of water—with respect to wind waves and swell—at a certain location and moment. A sea state is characterized by statistics, including the wave height, period, and power spectrum. The sea state varies with...

. Rogue waves seem not to have a single distinct cause, but occur where physical factors such as high winds and strong currents cause waves to merge together to create a single exceptionally large wave.

Background

Once lacking hard evidence for their existence, rogue waves are now known to be a natural ocean phenomenon. Eyewitness accounts from mariners and damages inflicted on ships have long suggested they occurred; however, their scientific measurement was only positively confirmed following measurements of the "Draupner wave

Draupner wave

The Draupner wave or New Year's wave was the first rogue wave to be detected by a measuring instrument, occurring at the Draupner platform in the North Sea off the coast of Norway on January 1, 1995...

", a rogue wave at the Draupner platform

Draupner platform

The Draupner platform is a complex consisting of the Draupner S and E riser platforms in the North Sea. It is located in the Norwegian North Sea block 16/11 offshore Norway. The complex consists of seven risers and two riser platforms standing in water depth and linked by a bridge...

, in the North Sea

North Sea

In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...

on January 1, 1995. During this event, minor damage was inflicted on the platform, confirming that the reading was valid. Satellite images have also confirmed their existence.

Freak waves have been cited in the media as a likely source of the sudden, inexplicable disappearance of many ocean-going vessels. One of the very few cases in which evidence exists that may indicate a freak wave incident is the 1978 loss of the freighter MS München

MS München

MS München was a German LASH carrier of the Hapag-Lloyd line that sank with all hands for unknown reasons in a severe storm in December 1978....

. In February 2000, a British oceanographic research vessel sailing in the Rockall Trough west of Scotland encountered the largest waves ever recorded by scientific instruments in the open ocean, with a SWH of 18.5 metres (60.7 ft) and individual waves up to 29.1 metres (95.5 ft). "In 2004 scientists using three weeks of radar images from European Space Agency satellites found ten rogue waves, each 25 meters or higher."

A rogue wave is distinct from a tsunami

Tsunami

A tsunami is a series of water waves caused by the displacement of a large volume of a body of water, typically an ocean or a large lake...

. Tsunamis are caused by mass displacement, such as sudden movement

Earthquake

An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...

of the ocean floor. They propagate at high speed over a wide area and are more or less unnoticeable in deep water, only becoming dangerous as they approach the shoreline and the ocean floor becomes shallower. They do not present a threat to shipping at sea (the only ships lost in the 2004 Asian tsunami

2004 Indian Ocean earthquake

The 2004 Indian Ocean earthquake was an undersea megathrust earthquake that occurred at 00:58:53 UTC on Sunday, December 26, 2004, with an epicentre off the west coast of Sumatra, Indonesia. The quake itself is known by the scientific community as the Sumatra-Andaman earthquake...

were in port). A rogue wave, on the other hand, is a highly localized phenomenon both in space and duration, most frequently occurring far out at sea.

Rogue waves may sometimes be referred to as "hundred-year waves," due to the supposed likelihood of their occurrence. They should not be confused, however, with the hundred-year wave

Hundred-year wave

A hundred-year wave is a statistically projected water wave, the height of which, on average, is met or exceeded once in a hundred years for a given location. The likelihood of this wave height being attained at least once in the hundred-year period is 63%...

, which is a statistical

Statistics

Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....

prediction of the highest wave likely to occur in a hundred-year period in a particular body of water. These predictions are typically based on wave models which do not take rogue waves into account.

History

It is common for mid-ocean storm waves to reach 7 metres (23 ft) in height, and in extreme conditions such waves can reach heights of 15 metres (49.2 ft).
However, for centuries maritime folklore

Folklore

Folklore consists of legends, music, oral history, proverbs, jokes, popular beliefs, fairy tales and customs that are the traditions of a culture, subculture, or group. It is also the set of practices through which those expressive genres are shared. The study of folklore is sometimes called...

told of the existence of much larger waves — up to 30 metres (98.4 ft) in height (approximately the height of a 10-story building) — that could appear without warning in mid-ocean, against the prevailing current and wave direction, and often in perfectly clear weather. Such waves were said to consist of an almost vertical wall of water preceded by a trough so deep that it was referred to as a "hole in the sea"; a ship encountering a wave of such magnitude would be unlikely to survive the tremendous pressures exerted by the weight of the breaking water, and would almost certainly be sunk in a matter of minutes.

Research has confirmed that waves of up to 35 metres (114.8 ft) in height are much more common than mathematical probability theory

Probability theory

Probability theory is the branch of mathematics concerned with analysis of random phenomena. The central objects of probability theory are random variables, stochastic processes, and events: mathematical abstractions of non-deterministic events or measured quantities that may either be single...

would predict using a Rayleigh distribution of wave heights. In fact, they seem to occur in all of the world's oceans many times every year. This has caused a re-examination of the reasons for their existence, as well as reconsideration of the implications for ocean-going ship design.

Rogue waves may also occur in lakes. A phenomenon known as the "Three Sisters" is said to occur in Lake Superior

Lake Superior

Lake Superior is the largest of the five traditionally-demarcated Great Lakes of North America. It is bounded to the north by the Canadian province of Ontario and the U.S. state of Minnesota, and to the south by the U.S. states of Wisconsin and Michigan. It is the largest freshwater lake in the...

when a series of three large waves forms. The second wave hits the ship's deck before the first wave clears. The third incoming wave adds to the two accumulated backwashes and suddenly overloads the ship deck with tons of water. The phenomenon was implicated in the sinking of the on Lake Superior in November 1975.

Occurrence

In the course of Project MaxWave, researchers from the GKSS Research Centre, using data collected by ESA satellite

Satellite

In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....

s, identified a large number of radar signatures that have been portrayed as evidence for rogue waves. Further research is under way to develop better methods of translating the radar echoes into sea surface elevation, but at present this technique is not proven.

Causes

Because the phenomenon of rogue waves is still a matter of active research, it is premature to state clearly what the most common causes are or whether they vary from place to place. The areas of highest predictable risk appear to be where a strong current

Ocean current

An ocean current is a continuous, directed movement of ocean water generated by the forces acting upon this mean flow, such as breaking waves, wind, Coriolis effect, cabbeling, temperature and salinity differences and tides caused by the gravitational pull of the Moon and the Sun...

runs counter to the primary direction of travel of the waves; the area near Cape Agulhas

Cape Agulhas

Cape Agulhas is a rocky headland in the Western Cape, South Africa. It is the geographic southern tip of Africa and the official dividing point between the Atlantic and Indian oceans...

off the southern tip of Africa is one such area; the warm Agulhas current

Agulhas Current

The Agulhas Current is the Western Boundary Current of the southwest Indian Ocean. It flows down the east coast of Africa from 27°S to 40°S. It is narrow, swift and strong...

runs to the southwest, while the dominant winds are westerlies

Westerlies

The Westerlies, anti-trades, or Prevailing Westerlies, are the prevailing winds in the middle latitudes between 30 and 60 degrees latitude, blowing from the high pressure area in the horse latitudes towards the poles. These prevailing winds blow from the west to the east, and steer extratropical...

. However, since this thesis does not explain the existence of all waves that have been detected, several different mechanisms are likely, with localised variation. Suggested mechanisms for freak waves include the following:

Diffractive
Diffraction
Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Italian scientist Francesco Maria Grimaldi coined the word "diffraction" and was the first to record accurate observations of the phenomenon in 1665...

focus
Focus (geometry)
In geometry, the foci are a pair of special points with reference to which any of a variety of curves is constructed. For example, foci can be used in defining conic sections, the four types of which are the circle, ellipse, parabola, and hyperbola...

ing — According to this hypothesis, coast shape or seabed shape directs several small waves to meet in phase. Their crest heights combine to create a freak wave.
Focusing by currents — Waves from one current are driven into an opposing current. This results in shortening of wavelength, causing shoaling (i.e., increase in wave height), and oncoming wave trains to compress together into a rogue wave. This happens off the South African coast, where the Agulhas current
Agulhas Current
The Agulhas Current is the Western Boundary Current of the southwest Indian Ocean. It flows down the east coast of Africa from 27°S to 40°S. It is narrow, swift and strong...

is countered by westerlies
Westerlies
The Westerlies, anti-trades, or Prevailing Westerlies, are the prevailing winds in the middle latitudes between 30 and 60 degrees latitude, blowing from the high pressure area in the horse latitudes towards the poles. These prevailing winds blow from the west to the east, and steer extratropical...

.
Nonlinear effects — It seems possible to have a rogue wave occur by natural, nonlinear processes from a random background of smaller waves. In such a case, it is hypothesised, an unusual, unstable wave type may form which 'sucks' energy from other waves, growing to a near-vertical monster itself, before becoming too unstable and collapsing shortly after. One simple model for this is a wave equation known as the nonlinear Schrödinger equation
Nonlinear Schrödinger equation
In theoretical physics, the nonlinear Schrödinger equation is a nonlinear version of Schrödinger's equation. It is a classical field equation with applications to optics and water waves. Unlike the Schrödinger equation, it never describes the time evolution of a quantum state...

(NLS), in which a normal and perfectly accountable (by the standard linear model) wave begins to 'soak' energy from the waves immediately fore and aft, reducing them to minor ripples compared to other waves. The NLS can be used in deep water conditions. In shallow water, waves are described by the Korteweg–de Vries equation
Korteweg–de Vries equation
In mathematics, the Korteweg–de Vries equation is a mathematical model of waves on shallow water surfaces. It is particularly notable as the prototypical example of an exactly solvable model, that is, a non-linear partial differential equation whose solutions can be exactly and precisely specified...

or the Boussinesq equation
Boussinesq approximation (water waves)
In fluid dynamics, the Boussinesq approximation for water waves is an approximation valid for weakly non-linear and fairly long waves. The approximation is named after Joseph Boussinesq, who first derived them in response to the observation by John Scott Russell of the wave of translation...

. These equations also have non-linear contributions and show solitary-wave solutions. A rogue wave consistent with the nonlinear Schrödinger equation was produced in a laboratory water tank in 2011.
Normal part of the wave spectrum — Rogue waves are not freaks at all but are part of normal wave generation process, albeit a rare extremity.
Wind waves — While it is unlikely that wind alone can generate a rogue wave, its effect combined with other mechanisms may provide a fuller explanation of freak wave phenomena. As wind blows over the ocean, energy is transferred to the sea surface. When strong winds from a storm happen to blow in the opposing direction of the ocean current the forces might be strong enough to randomly generate rogue waves. Theories of instability mechanisms for the generation and growth of wind waves—although not on the causes of rogue waves—are provided by Phillips and Miles.

The spatio-temporal focusing seen in the NLS equation can also occur when the nonlinearity is removed. In this case, focusing is primarily due to different waves coming into phase, rather than any energy transfer processes. Further analysis of rogue waves using a fully nonlinear model by R.H. Gibbs (2005) brings this mode into question, as it is shown that a typical wavegroup focuses in such a way as to produce a significant wall of water, at the cost of a reduced height.

A rogue wave, and the deep trough commonly seen before and after it, may last only for some minutes before either breaking, or reducing in size again. Apart from one single rogue wave, the rogue wave may be part of a wave packet consisting of a few rogue waves. Such rogue wave groups have been observed in nature.

There are three categories of freak waves:

"Walls of water" travelling up to 10 km (6.2 mi) through the ocean
"Three Sisters", groups of three waves
Single, giant storm waves, building up to fourfold the storm's waves height and collapsing after some seconds

A research group at the Umeå University

Umeå University

Umeå University is a university in Umeå in the mid-northern region of Sweden. The university was founded in 1965 and is the fifth oldest within Sweden's present borders....

, Sweden in August 2006 showed that normal stochastic

Stochastic

Stochastic refers to systems whose behaviour is intrinsically non-deterministic. A stochastic process is one whose behavior is non-deterministic, in that a system's subsequent state is determined both by the process's predictable actions and by a random element. However, according to M. Kac and E...

wind driven waves can suddenly give rise to monster waves. The nonlinear evolution of the instabilities was investigated by means of direct simulations of the time-dependent system of nonlinear equations.

Applications

The possibility of the artificial stimulation of rogue wave phenomena has attracted research funding from DARPA, an agency of the United States Department of Defense

United States Department of Defense

The United States Department of Defense is the U.S...

. Bahram Jalali and other researchers at UCLA studied microstructured optical fibers near the threshold of soliton

Soliton

In mathematics and physics, a soliton is a self-reinforcing solitary wave that maintains its shape while it travels at constant speed. Solitons are caused by a cancellation of nonlinear and dispersive effects in the medium...

supercontinuum

Supercontinuum

In optics, a supercontinuum is formed when a collection of nonlinear processes act together upon a pump beam in order to cause severe spectral broadening of the original pump beam. The result is a smooth spectral continuum...

generation and observed rogue wave phenomena. After modeling the effect, the researchers announced that they had successfully characterized the proper initial conditions for generating rogue waves in any medium. Additional works carried out in optics have pointed out the role played by a nonlinear structure called Peregrine soliton

Peregrine soliton

The Peregrine soliton is an analytic solution of the nonlinear Schrödinger equation. This solution has been proposed in 1983 by Howell Peregrine, researcher at the mathematics department of the University of Bristol.- Main properties :...

that may explain those waves that appear and disappear without leaving a trace.

Reported encounters

It should be noted that many of these encounters are only reported in the media, and are not examples of open ocean rogue waves. Often, in popular culture, an endangering huge wave is loosely denoted as a rogue wave, while it has not been (and most often cannot be) established that the reported event is a rogue wave in the scientific sense — i.e. of a very different nature in characteristics as the surrounding waves in that sea state

Sea state

and with very low probability of occurrence (according to a Gaussian process

Gaussian process

In probability theory and statistics, a Gaussian process is a stochastic process whose realisations consist of random values associated with every point in a range of times such that each such random variable has a normal distribution...

description as valid for linear wave theory).

This section lists a limited selection of notable incidents.

Nineteenth century

The Eagle Island lighthouse (1861) – water broke the glass of the structure's east tower and flooded it, implying a wave that surmounted the 40 m (131.2 ft) cliff and overwhelmed the 26 m (85.3 ft) tower.
Flannan Isles
Flannan Isles
Designed by David Alan Stevenson, the tower was constructed for the Northern Lighthouse Board between 1895 and 1899 and is located near the highest point on Eilean Mòr. Construction was undertaken by George Lawson of Rutherglen at a cost of £6,914 inclusive of the building of the landing places,...

(1900) – three lighthouse keepers vanished after a storm that resulted in wave-damaged equipment being found 34 metres (111.5 ft) above sea level.

Twentieth century

- In 1909, it left Durban, South Africa with 211 passengers and crew but did not reach Cape Town, South Africa.

Voyage of the James Caird - In 1916 Sir Ernest Shackleton encountered a wave he termed "gigantic" while piloting a lifeboat/whaler from Elephant Island to South Georgia Island. (1933) – triangulated at 112 feet (34.1 m). (1942) – broadsided by a 92 feet (28 m) wave and listed briefly about 52 degrees before slowly righting.
SS Michelangelo (1966) – hole torn in superstructure, heavy glass smashed 80 feet (24.4 m) above the waterline, and 3 deaths. (1975) – lost on Lake Superior
Lake Superior
Lake Superior is the largest of the five traditionally-demarcated Great Lakes of North America. It is bounded to the north by the Canadian province of Ontario and the U.S. state of Minnesota, and to the south by the U.S. states of Wisconsin and Michigan. It is the largest freshwater lake in the...

. A Coast Guard report blamed water entry to the hatches, which gradually filled the hold, or alternatively errors in navigation or charting causing damage from running onto shoal
Shoal
Shoal, shoals or shoaling may mean:* Shoal, a sandbank or reef creating shallow water, especially where it forms a hazard to shipping* Shoal draught , of a boat with shallow draught which can pass over some shoals: see Draft...

s. However, another nearby ship, the , was hit at a similar time by two rogue waves and possibly a third, and this appeared to coincide with the sinking around ten minutes later. (1978) – lost at sea leaving only "a few bits of wreckage" and signs of sudden damage including extreme forces 66 feet (20.1 m) above the water line. Although more than one wave was probably involved, this remains the most likely sinking due to a freak wave.
Esso Languedoc A 25–30m wave washed across the deck from the stern of the French supertanker, and was photographed by the first mate, Philippe Lijour, in 1980.
Fastnet Lighthouse Struck by 48 m (157.5 ft) wave in 1985
Draupner wave
Draupner wave
The Draupner wave or New Year's wave was the first rogue wave to be detected by a measuring instrument, occurring at the Draupner platform in the North Sea off the coast of Norway on January 1, 1995...

(North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...

, 1995) – First rogue wave confirmed with scientific evidence, it had a maximum height of 25.6 metres (84 ft). – North Atlantic, September 1995, 29 metres (95.1 ft), during Hurricane Luis
Hurricane Luis
Hurricane Luis was one of the deadliest and most destructive hurricanes of the 1995 Atlantic hurricane season, with maximum sustained winds of 140 mph . The storm was the twelfth tropical storm, sixth hurricane, and second major hurricane of the season...

: The Master said it "came out of the darkness" and "looked like the White Cliffs of Dover
White cliffs of Dover
The White Cliffs of Dover are cliffs which form part of the British coastline facing the Strait of Dover and France. The cliffs are part of the North Downs formation. The cliff face, which reaches up to , owes its striking façade to its composition of chalk accentuated by streaks of black flint...

." Newspaper reports at the time described the cruise liner as attempting to "surf
Surfing
Surfing' is a surface water sport in which the surfer rides a surfboard on the crest and face of a wave which is carrying the surfer towards the shore...

" the near-vertical wave in order not to be sunk.

Twenty-first century

and Caledonian Star (South Atlantic, 2001) encountered 30 metres (98.4 ft) freak waves. Bridge windows on both ships were smashed, and all power and instrumentation lost.

U.S. Naval Research Laboratory ocean-floor pressure sensor
Pressure sensor
A pressure sensor measures pressure, typically of gases or liquids. Pressure is an expression of the force required to stop a fluid from expanding, and is usually stated in terms of force per unit area. A pressure sensor usually acts as a transducer; it generates a signal as a function of the...

s detected a freak wave caused by Hurricane Ivan
Hurricane Ivan
Hurricane Ivan was a large, long-lived, Cape Verde-type hurricane that caused widespread damage in the Caribbean and United States. The cyclone was the ninth named storm, the sixth hurricane and the fourth major hurricane of the active 2004 Atlantic hurricane season...

in the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

, 2004. The wave was around 27.7 metres (90.9 ft) high from peak to trough, and around 200 metres (656.2 ft) long.
Norwegian Dawn
Norwegian Dawn
Norwegian Dawn is a cruise ship that entered service in 2002 and is in operation with Norwegian Cruise Line.-History:The ship entered service at the end of 2002. She was intended to operate with Star Cruises under the name SuperStar Scorpio, but it was decided that she would be delivered to Star's...

, (Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...

,[U.S.] 2005) On April 16, 2005, after sailing into rough weather off the coast of Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...

, Norwegian Dawn encountered a series of three 70 feet (21.34 m) rogue waves. The third wave damaged several windows on the 9th and 10th decks and several decks were flooded. Damage, however, was not extensive and the ship was quickly repaired. Four passengers were slightly injured in this incident.
Aleutian Ballad, (Bering Sea
Bering Sea
The Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves....

, 2005) footage of what is identified as a rogue wave appears in an episode of Deadliest Catch
Deadliest Catch
Deadliest Catch is a documentary/reality television series produced by Original Productions for the Discovery Channel. It portrays the real life events aboard fishing vessels in the Bering Sea during the Alaskan king crab and C. opilio crab fishing seasons.The Aleutian Islands port of Dutch Harbor,...

. The wave cripples the vessel, causing the boat to tip for a short period onto its side. This is one of the few video recordings of what might be a rogue wave.
It has been suggested that these types of waves may be responsible for the loss of several low-flying aircraft, namely U.S. Coast Guard helicopters on Search and Rescue missions.
MS Louis Majesty, (Gulf of Marseille, Mediterranean Sea, March 2010). An unexpected pack of three waves of 26 feet (7.9 m) hit the ship while on a cruise between Carthagena and Marseille. Two passengers were killed in a lounge by flying glass from a shattered window. Damage to the ship was done by the second and third waves. While this wave was much lower than freak waves appearing in open oceans, published evidence indicates that its behaviour was similar to that of freak waves.

Loss estimates

Freak waves have been cited in the media as a likely source of the sudden, inexplicable disappearance of many ocean-going vessels. However, although this is a credible explanation for unexplained losses, there is to date little clear evidence supporting this hypothesis nor any cases where the cause has been confirmed, and the claim is contradicted by information held by Lloyd's Register

Lloyd's Register

The Lloyd's Register Group is a maritime classification society and independent risk management organisation providing risk assessment and mitigation services and management systems certification. Historically, as Lloyd's Register of Shipping, it was a specifically maritime organisation...

. A press release by the European Space Agency

European Space Agency

The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...

in 2004 made the claim that "200 large ships of 600ft long or more in the past two decades sunk without trace". However, at the time the claim was made, there had only been 142 ships of that size lost at sea in the time frame, all with clear, known causes . The main culprits were the Iran

Iran

Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...

ian and Iraq

Iraq

Iraq ; officially the Republic of Iraq is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert....

i air forces in the 1980s

1980s

File:1980s decade montage.png|thumb|400px|From left, clockwise: The first Space Shuttle, Columbia, lifted off in 1981; American President Ronald Reagan and Soviet leader Mikhail Gorbachev eased tensions between the two superpowers, leading to the end of the Cold War; The Fall of the Berlin Wall in...

during the Iran-Iraq war

Iran-Iraq War

The Iran–Iraq War was an armed conflict between the armed forces of Iraq and Iran, lasting from September 1980 to August 1988, making it the longest conventional war of the twentieth century...

. One of the very few cases in which clear evidence exists that may indicate a freak wave incident is the 1978 loss of the freighter MS München