The world's oceans claim on average one ship a week, often in mysterious circumstances. With little evidence to go on, investigators usually point at human error or poor maintenance but an alarming series of disappearances and near-sinkings, including world-class vessels with unblemished track records, has prompted the search for a more sinister cause and renewed belief in a maritime myth: the wall of water. Waves the height of an office block. Waves twice as large as any that ships are designed to ride over.
These are not tsunamis or tidal waves, but huge breaking walls of water that come out of the blue. Suspicions these were fact not fiction were roused in 1978, by the cargo ship München. She was a state-of-the-art cargo ship. The December storms predicted when she set out to cross the Atlantic did not concern her German crew. The voyage was perfectly routine until at 3am on 12 December she sent out a garbled mayday message from the mid-Atlantic. Rescue attempts began immediately with over a hundred ships combing the ocean. "We hoped to find at least a life-raft with people. We never found a living soul" says Captain Pieter de Nijs, München search coordinator.
The ship was never found. She went down with all 27 hands. An exhaustive search found just a few bits of wreckage, including an unlaunched lifeboat that bore a vital clue. It had been stowed 20m above the water line yet one of its attachment pins had twisted as though hit by an extreme force. The Maritime Court concluded that bad weather had caused an unusual event. Other seafarers could not help but consider the possibility of a mythical freak wave.
Freak waves are the stuff of legend. They aren't just rare, according to traditional views of the sea, they shouldn't exist at all. Oceanographers and meteorologists have long used a mathematical system called the linear model to predict wave height. This assumes that waves vary in a regular way around the average (so-called 'significant') wave height. In a storm sea with a significant wave height of 12m, the model suggests there will hardly ever be a wave higher than 15m. One of 30m could indeed happen - but only once in ten thousand years.
Except they do happen with startling frequency. Since 1990, 20 vessels have been struck by waves off the South African coast that defy the linear model's predictions. And on New Year's Day, 1985 a wave of 26m was measured hitting the Draupner oil rig in the North Sea off Norway. Concerned shipping operators wanted to know what was going on. The largest wave marine architects are required to accommodate in the design strength calculations is 15m from trough to crest. If that assumption were to be proved false, the whole world shipping industry would face some very tough choices.
What could cause such extreme waves? Curious about the spate of South African incidents, oceanographer Marten Grundlingh plotted the strikes on thermal sea surface maps. All the ships had been at the edge of the Agulhas Current, the meeting point of two opposing flows mixing warm Indian Ocean water with a colder Atlantic flow. Radar surveillance by satellite confirmed that wave height at the edge of this current could grow well beyond the linear model's predictions, especially if the wind direction opposed the current flow.
Problem solved: the answer was just to avoid certain ocean currents in certain weather conditions. There was nothing freakish about large waves; the mariners' myth was an explicable phenomenon. To science, this was one that didn't get away. "Out of nowhere... a wave twice as high as average. The ship went down like freefall" according to Göran Persson, Caledonian Star First Officer.
Unfortunately, ocean currents could not explain two near disastrous wave strikes in March 2001. Once more two reputable ships, designed to cope with the very worst conditions any ocean could throw at them, were crippled to the point of sinking. The Bremen and Caledonian Star were carrying hundreds of tourists across the South Atlantic. At 5am on 2nd March the Caledonian Star's First Officer saw something bearing down on them.
A 30m wave smashed over the ship, flooding the bridge and destroying much of the navigation and communication equipment. The Caledonian Star limped back to port, her crew and passengers grateful that the engines had kept running, despite the onslaught.
Just days earlier, the cruise liner Bremen had been less fortunate. 137 German tourists were aboard when she too faced an awesome wall of water in the South Atlantic. The impact knocked out all the instrumentation and all power, leaving them helpless in the tumultuous sea. Unable to maintain her course into the waves, there was a real risk the ship could go down and they knew none of the passengers would survive in lifeboats in such freezing conditions. With emergency power only, the crew battled to restart the engines. When they eventually succeeded, it opened the door to a very lucky escape. "We had said, 'This kind of thing can't happen; this kind of thing is too strange" says Al Osborne, wave mathematician.
No current could have created such huge waves. There is none in that part of the Atlantic. Clearly, there was another effect investigators needed to find. Except someone already had: it existed (on paper at least) in the world of quantum physics. Al Osborne is a wave mathematician with 30 years experience devising equations to describe open ocean wave patterns. Quantum physics has at its heart a concept called the Schrodinger Equation, a way of expressing the probability of something happening that is far more complex than the simple linear model. Al's theory is based on the notion that in certain unstable conditions, waves can steal energy from their neighbours. Adjacent waves shrink while the one at the focus can grow to an enormous size. His modified Schrodinger Equation had been rejected in the past as implausible, but with research attention centred on analysing these rogue waves - including global satellite radar surveillance by the new European Remote Sensing Satellite - data began to emerge backing his case. When Al came across the New Year's Day 1985 wave profiles from the Draupner oil rig, he saw his mathematical model played out in the real world.
Al's work - if correct - suggests that there are two kinds of waves out on the high seas; the classical undulating type described by the linear model and an unstable non-linear monster - a wave that at any time can start sucking up energy from waves around it to become a towering freak. The consequences for ship design could be stark.
Currently the biggest wave factored into most ship design is smooth, undulating and 15m high. A freak wave is not only far bigger, it is so steep it is almost breaking. This near-vertical wall of water is almost impossible to ride over - the wave just breaks over the ship. According to accident investigator, Rod Rainey, such a wave would exert a pressure of 100 tonnes per square metre on a ship, far greater than the 15 tonnes that ships are designed to withstand without damage. It's no wonder that even ships the size of the huge freighter München can sink without trace.
BBC Science §
6/45. In early June Admiral Halsey had taken over the fleet and was as customary with this change of command the Fifth Fleet became the Third Fleet.
6/5/45. USS Conklin is heavily damaged in a typhoon off Okinawa. A monstrous wave knocked the ship completely onto her side, at which point the ship lost all power and water. Fuel oil flooded into the ship. Three of her crew were killed immediately. Lt. Peter N. Meros and Rudolph Slavich S1c were swept over board, and Anthony Monti S1c was killed inside the ship by a collapsing hatch.
When Butler-class Destroyer Escorts rolled the critical angle of 72 degrees, the weight of the top-heavy masts inexorably continued the roll and dragged the ship to the bottom of the sea. The inclinometer of the Conklin measured a roll of 78 degrees.
Then, by what figuratively and perhaps literally can be termed the Hand of God, another freak wave hit the Conklin and rolled her back up so that the rest of her men survived with the superb seamanship and desperate efforts of their crew.
USS Conklin is put into Guam for emergency repairs.
6/17/45. USS Conklin sails for Mare Island Navy Yard for a complete overhaul.
when this is completed, she sails for SanTo: 1066AD
ROGUE WAVE SMASHES THE QUEEN ELIZABETH II
September 11, 1995. North Atlantic. Aboard the Queen Elizabeth II enroute from Cherbourg to New York.
During this crossing of the Atlantic, the Queen Elizabeth II had to change course to avoid Hurricane Luis. Despite this precaution, the vessel encountered seas of 18 meters with occasional higher crests. At 0400 the Grand Lounge windows, 22 meters above the water, stove in. But this was only a precursor.
"At 0410 the rogue wave was sighted right ahead, looming out of the darkness from 220°, it looked as though the ship was heading straight for the white cliffs of Dover. The wave seemed to take ages to arrive but it was probably less than a minute before it broke with tremendous force over the bow. An incredible shudder went through the ship, followed a few minutes later by two smaller shudders. There seemed to be two waves in succession as the ship fell into the 'hole' behind the first one. The second wave of 28-29 m (period 13 seconds), whilst breaking, crashed over the foredeck, carrying away the forward whistle mast.
"Captain Warwick admits that sometimes it can be difficult to gauge the height of a wave, but in this case the crest was more or less level with the line of sight for those on the bridge, about 29 m above the surface; additionally, the officers on the bridge confirmed that it was definitely not a swell wave. The presence of extreme waves was also recorded by Canadian weather buoys moored in the area, and the maximum measured height from buoy 44141 was 30 m (98 feet.)"
The Queen Elizabeth II survived the onslaught with minor damage; no passengers or crew members were injured.
28 posted on 01/12/2004 1:33:41 PM PST by John H K
[ Post Reply | Private Reply | To 10 | View Replies ]
Q: My dad told me once about a phenomenon called a "rogue" wave. He said that he recalled one striking an aircraft carrier and actually bending a corner of the flight deck. This might have been in the late '40s or so. Have you ever heard of this occurring? I have done some checking and found very little information on rogue waves thus far. Thanks in advance.
A: You've touched on a fascinating topic. The only extensive discussion of "rogue" waves that I've come across is in Willard Bascom's book, Waves and Beaches. I have the paperback published by Anchor Books in 1980. In it, he describes rogue waves as "great solitary waves whose crests tower above their fellows and scare the living daylights out of the luckless mariners in their path."
In brief, winds blowing across water create water waves. The waves you see in any part of the ocean are really made of combinations of trains of waves from many different places. At times, the crests of waves will come together in a way to combine into a bigger wave. At other times a crest and a trough will combine to make a smaller wave.
These combinations are random. Bascom cites the work of one scientist who examined the probability of the occurrence of large single waves. This work shows that one wave in 23 is twice the size of the height of the average wave in a location. One in 1,175 is over three times average height and only one in 300,000 is more than four times the average height. Also, such large waves last only a brief time and then shrink as the combined wave trains that make then continue their own way.
I had not heard of the incident your father describes, but Bascom has many in his book. One of the most hair-raising rogue wave stories describes what happened to the 81,000-ton, 1,000-foot-long liner the Queen Mary in late 1942 during World War II. It was loaded with 15,000 American soldiers bound for England when it hit a storm 700 miles off Scotland. Without warning, "one freak mountainous wave" hit the ship broadside. The ship listed enough for water to wash onto her upper decks. For a few seconds experienced seamen aboard thought the Queen Mary was going to roll over. But it righted itself and continued. Rogue waves have sunk other ships, including large ones. Bascom says rogue waves probably explain what happened to many ships that have disappeared without a trace.
I highly recommend his book for anyone interested in the oceans or the surf. It's great if you go to the beach and begin wondering why surf acts as it does.
It would also make good reading on a cruise for anyone who's scientifically minded.
» HorizonArchivesMessage boardAbout HorizonTV & RadioPrintable version
About the BBCContact UsHelpLike this page?Send it to a friend!
First shown: BBC Two, Thursday 14 November 2002
Freak Wave Screensaver
Programme summary Questions and answersTranscriptWeblinksScreensaverWallpaper Install freak waves on your own computer. More information on the screensaver and wallpaper.
Freak Wave - transcriptNARRATOR (BERNARD HILL): There is something out at sea terrorising the world's shipping.CAPT RONALD WARWICK (Queen Elizabeth 2): Out of the darkness came this great wall of water. I have never seen a wave as big as this in my whole life.NARRATOR: It can strike out of the blue with devastating consequences.CAPT BARRY PECK: You hit solid water and it is like running into a brick wall. The entire bridge was wrecked.CAPT DAI DAVIES (Smit Marine South Africa): Horrific, monstrous. You feel as if the end of the world has come.NARRATOR: This is the story of a wave that is sinking ships around the world, a killer that defies all scientific understanding and that no ship is designed to withstand. It is one of the best kept secrets of the sea, that once a week a ship sinks to the bottom of the ocean, often without Mayday or any clue as to what happened. One of the most mysterious of these disappearances is that of the München. The München was a vast new type of cargo ship, the length of 2½ football pitches she was the pride of the German merchant navy. On 7 December 1978 she set sail on a routine trip to America. On board were 27 crew, including Uwe Hinrichs.THEODOR HINRICHS: This was my son Uwe, 20 years old. He liked going to sea. He said it was the safest ship in the world. Everybody said it was unsinkable, the best ship in the world.NARRATOR: That night in December there was a giant storm raging across the Atlantic. The waves were the size of houses, but that would not have troubled the München. For a ship so powerful and well maintained such storms were just routine. It was assumed that all was well and going to schedule, until 3am on the night of 12 December. It was an SOS from the München. She was in trouble and needed help, but at this stage no-one was too alarmed because even if damaged the powerful München could float for days.THEODOR HINRICHS: At the beginning we were very calm. I told myself this couldn't happen to the München. It's so safe. Everything had been taken care of. They'd thought about everything.NARRATOR: Within hours search and rescue planes were sent to find her and all the ships in the busy shipping route came to join in the search. Like a police hunt, they were lined up three miles apart combing vast areas of the ocean for the München. It was the biggest search in the history of shipping. In charge was Captain Pieter de Nijs.CAPT PIETER DE NIJS: We hoped to find the ship, or at least people or a lifeboat, a life raft with people and we never found any living soul which every day became more disappointing.NARRATOR: All that was recovered was an empty lifeboat and some wreckage.PIETER DE NIJS: That a ship can be in trouble that can happen to any ship. It happens all the time everywhere now and then, but that it completely disappeared. that such a big modern ship could disappear that was surprising.NARRATOR: For some reason the great ship and her crew had disappeared off the face of the earth and no-one could understand why. An investigation started immediately, going over every detail of her design and the few remains that had been found. The only clue to what happened was found on the recovered lifeboat. Normally it hung 20 metres above the waterline and it was one of the tiny metal pins that it hung from that drew the investigators' attention. One of them was Werner Hummel.CAPT WERNER HUMMEL ('München' Investigator): The key actually to what, what could have happened to the München is the forward block of the starboard lifeboat. The, which is shown here on, on this picture. We see here on the pictures these steel pins, pins bent from forward to aft. This indicates that the boat hanging underneath was struck by a tremendous force forward aft which caused these bendings of these rather strong steel pins.NARRATOR: Some huge force had hurled the lifeboat out of its metal pins 20m up above sea-level, but what this force was was a mystery. The Maritime Court could only conclude that bad weather caused an unusual event which led to the sinking of the ship, but many mariners suspected they knew what sunk the München, something that according to legend sinks a huge number of ships every year: a freak wave. The freak, or rogue, wave is one of the great myths of the sea.CAPT TREVOR FAITHFUL: All my sea career I've been hearing stories about rogue waves.NARRATOR: Mariners talk of a single breaking wave the size of a tower block that can rear up out of nowhere.DAI DAVIES: It was colossal.CAPT BARRY PECK: At least 80ft high, probably even bigger.CAPT KARL-ULRICH LAMPE (MS Caledonian Star): We estimate the height of the wave 30 metres.RONALD WARWICK: It looked enormous, it looked like a white cliff.GÖRAN PERSSON (First Officer, MS Caledonian Star): It was just like a mountain, a wall of water coming against us.RONALD WARWICK: I've never seen a wave as big as this in my whole life.NARRATOR: It's not a tsunami or tidal wave, it's not caused by earthquakes or giant landslides. No-one knows where it comes from or why it happens.KARL-ULRICH LAMPE: The freak wave is a huge, steep wave coming out of the blue without any prediction, any expectations. It's just there.NARRATOR: But there's one small problem with all these stories. According to all scientific knowledge of the sea freak waves are practically impossible. Scientists have understood ocean waves for centuries. They are simply made by the wind. The stronger the wind and the longer it blows the bigger the waves. In order to predict the biggest wave a ship will meet scientists use a set of mathematical equations called the Linear Model. This says that in any sea condition there is a limit to how big the largest wave will be and that mariners tales of monster waves that come out of nowhere have got to be wrong.ROD RAINEY (Marine & Offshore Engineering, Atkins): Mariners are like fishermen aren't they. I mean they, sure they come back from the sea and they tell all kinds of interesting stories and people look at them suspiciously.PROF. AL OSBORNE (University of Turin): It's sort of like you know the fish that got away and he says oh that was 10 metres long, you know. Well waves are sort of the same.NARRATOR: Jim Gunson of the Met Office uses the Linear Model to explain why freak waves shouldn't exist.DR JIM GUNSON (Met Office): Using the Linear Model for a given sea state this bell-shaped graph gives the probability of a certain wave height and it's like the inner population of children in a class. There is an average height of the children and most children are around that height. Some are quite a bit taller or shorter, but there's, the chance that a child is, is three or four times the height of the average child is very, very small.NARRATOR: So according to the Linear Model even in a fierce storm where average wave height may be 12 metres the chance of meeting a 30m wall of water is practically zero.JIM GUNSON: Using the Linear Model for a 12m sea state the chance of finding a 30m trough to crest wave height is 10 to the minus 5 which is 0.00001. To put it in perspective the chan, a wave like that would come along using the Linear Model once every 10,000 years.NARRATOR: The Linear Model is so well accepted that the entire multi-billion pound shipping industry relies on it. Meteorologists use it to predict wave height and naval architects to calculate ship's strength and the biggest wave used in ship design is just 15m. The idea that there might be freak waves out there seemed impossible. Instead any mysterious disappearances at sea have been blamed on far likely culprits, like corrosion and human error, but then one day something happened that forced scientists to look again at their ideas about ocean waves. On New Year's Day 1995 a storm was brewing in the North Sea. The Draupner oil rig was 100 miles out in the harshest of weather. The sensors were regularly reading waves of 12m when suddenly out of the blue came a wave that was so high and so steep scientists had thought it was impossible.AL OSBORNE: For me it changed everything, really changed everything. This wave is at 26m. It's so much bigger than the background sea state.JIM GUNSON: When the New Year's Day wave came along which fits this picture, a 30m crest to trough height in a 12m sea state, alarm bells started going off because of the very low probability of this wave, yet we saw it.NARRATOR: The sensors measured a wave so steep and so high it should only occur once in every 10,000 years. Suddenly it seemed that the mariners might be right after all. The New Year wave shocked wave experts. Among them Julian Wolfram. He has spent years since then studying the same part of the North Sea looking for more freak waves.PROF. JULIAN WOLFRAM (Heriot-Watt University): What we need to do is to study waves like this because we need to know how frequently they occur because if they occur quite frequently they could actually pose a serious danger to offshore structures and ships.NARRATOR: Wolfram was looking for any waves that were bigger than the Linear Model would predict and to measure them he installed a radar device looking down to the sea's surface.JULIAN WOLFRAM: We have a device which faces down to the surface of the sea and basically sends out an electric pulse, hits the surface of the water and comes back again and we time the amount of time it takes to go down and come back and from that we can estimate the distance from the radar to the wave and we do that continuously so we actually get the profile of the surface.NARRATOR: Over four years Wolfram measured every large wave that hit the platform and when he plotted the size of these waves compared to the height of the waves around them he found something completely unexpected. The Linear Model predicts that when you plot the height of individual waves relative to the waves either side they should all lie on a straight line and when the average size of the waves were small the Linear Model held true, but he found 24 waves that veered well above the line. These biggest waves occurred far more frequently than the Linear Model predicted. It appeared that these 24 waves were a completely different sort of beast.JULIAN WOLFRAM: One of the things we learn when we plotted out the graph was that in fact the really extreme waves are different from the slightly smaller waves. They have different characteristics, they tend to be significantly steeper, they also tend to be higher than we would normally expect based on the ordinary theories we've used up to date. They're unusual, they are freak waves.NARRATOR: It seemed Wolfram really had found the rogue wave of mariners' myth. For the shipping industry Wolfram's research could have been a disaster. If there really were freak waves out there then potentially billions of dollars were at risk. It could mean having to redesign every single ship. With so much at stake scientists needed to understand what was going on. Where did freak waves come from and was there any way of predicting them? Searching for clues they looked at where mariners have reported seeing freak waves and found one place where they seemed to happen over and over again - South Africa. The southern cape of Africa is a major shipping route with millions of tons of cargo being shifted every year. The seas here may look calm but for years they have been notorious to sailors for the ferocity of their waves. Captain Dai Davies is one of the leading salvage experts in South Africa. He's seen the damage these waves can cause dozens of times.DAI DAVIES: The Neptune Sapphire was a brand new vessel on her maiden voyage. It was as if a cutting torch had cut the ship in half completely. Atlas Pride happened in horrific weather. This big wave just came out of nowhere, hit the bow and destroyed the whole bow. Mimosa was a very big vessel. The ship's side plating was punched in, completely smashed in causing a hole to be formed you could fit three double-decker buses into. When I went aboard the ship to carry out the salvage the Captain, who was a very experienced Norwegian Master, said it was the biggest wave he'd ever seen in his life, he'd ever seen.NARRATOR: Since 1990 20 ships have been devastated by rogue waves off the coast of South Africa. Scientists like Marten Grundlingh decided to find out what was going on in these waters to make them so dangerous, so they plotted the locations of all the accidents on a chart and when they laid this over an infrared image of the ocean they noticed a very striking pattern. All the points lay along the same strong ocean current, the Agulhas current.DR MARTEN GRUNDLINGH (Council for Scientific & Industrial Research, SA): These crosses that we plotted on all the accidents that occurred off the South African coast they're all located in this red band and this band signifies the Agulhas current which is a major current flowing down the South African coast that originates in the Indian Ocean so it's warmer water and therefore visible on this infrared image.NARRATOR: The Agulhas current is a huge ocean current of warm water streaming down from the north. On its own it shouldn't cause freak waves, but scientists suspected that if the current heading one way were to meet wind and waves coming in the opposite direction then perhaps this could be the source of all the trouble.MARTEN GRUNDLINGH: Down here in the south is the area where all our waves and storms are generated, deep in the southern ocean and they propagate in a north-easterly direction up like this and this is the area then where the Agulhas current coming from the north-east meet up with these wave and swell conditions coming from, from this area down here, so this is the area, the danger area in terms of these two significant phenomena.NARRATOR: But it was only when Grundlingh got access to a new type of satellite, one using radar, that he could actually measure the height of waves in the current and it was just as Grundlingh had thought. When the waves were going with the current they were small, but when the waves were going in the opposite direction to the current the effect was dramatic.MARTEN GRUNDLINGH: What we have here is a plot of the wave height. Outside the current and the wave height inside the current and what is quite conspicuous here is this very, very significant increase in the wave height as the satellite moved across the current.NARRATOR: When the waves had to fight the current they grew massive. The current pushed against them driving them so high and steep a monster would rear up. Here it seemed was a simple explanation for the mythical freak.MARTEN GRUNDLINGH: These things are not really what used to be called freak waves. They, they're not of a freakish nature, but they're quite common. They will occur every time that there are waves moving against the current and that happens very, very often.NARRATOR: This simple explanation was a godsend for the shipping industry. It meant that huge waves were easy to avoid. Just steer around the Agulhas current. There was no need to spend huge sums redesigning the world's fleet and when scientists looked at other places where freak waves were most often reported, like Norway, straightforward local conditions were again found to be the cause. Ships were simply ordered to follow a different route and avoid the danger areas. There was now no need to question science's understanding of the sea and it seemed that the freak wave mystery had been solved, but then something happened last year in the South Atlantic that no-one could explain away and which would shatter all the simple explanations. In February 2001 the Caledonian Star spent several weeks cruising around the Antarctic. On board were 105 British and American tourists enjoying the wonders of the southern ocean. The Caledonian Star is a strong as almost any ship in the world, specially built to cope with the ice and harsh conditions, so when they received a bad weather report for the journey home no-one on board was worried.KARL-ULRICH LAMPE: We had a weather forecast predicting gale force winds.GÖRAN PERSSON: It's a very common weather report. The ship is expected to face that sort of weather all the time.KARL-ULRICH LAMPE: That didn't bother us at all.NARRATOR: The storm worsened till the waves were over 12 metres high. The ship rode these easily and still no-one was concerned until 5.30pm on 2 March when the First Officer saw something unexpected.GÖRAN PERSSON: Out of nowhere I saw in the distance about a mile away a wave that appeared to be twice the height of the average wave height.KARL-ULRICH LAMPE: We estimate the height of the wave 30m which is extremely high.GÖRAN PERSSON: It was just like a mountain, a wall of water coming against us and it came from a different direction like 30° on the starboard bow.NARRATOR: As the wall of water approached they saw a huge trough open up before it.GÖRAN PERSSON: The ship probably went down at an angle like this and more or less like a free-fall because the waves were moving very fast and when the ship is tipping she fell like this and talking to the other people on board the ship they were all falling against the bulkheads in the forward part of the section wherever they were, so she went like this directly hitting a wave and just buried the bow into the wave. The helmsman he was standing here and he actually took cover and when he looked down he could not see the crest of the wave.KARL-ULRICH LAMPE: You had a wall of water ahead of you and the ship was just running into that wall.GÖRAN PERSSON: The whole bridge was like an explosion and I was washed like I was blown away by water jet over to the other side, me and the helmsman we were lying on top of each other underwater fighting books and cushions and shorts and I had to swim, actually I had to swim and, and crawl to get back to the controls to be able to put the ship back on, on course.NARRATOR: The effect of the wave was devastating shattering the ship's instrumentation. The ship was effectively blind.KARL-ULRICH LAMPE: We lost our radars, the gyro compasses, the echo sounders, the sonar, parts of the radio communication.GÖRAN PERSSON: It was a very humbling experience. Of course it went through your mind that this, this might be it, we might not make it.NARRATOR: But the Caledonian Star was lucky. Her engines were still working. The crew boarded up the windows and eventually the ship limped back to port, but another ship out at sea at that time was less fortunate. The Bremen was a German cruise liner. Again she was built to withstand anything the South Atlantic could throw at her. On board were 137 tourists. They too were hit by a giant 30m wave which devastated the bridge.CAPT HEINZ AYE (MS Bremen): The bridge wasn't operable. All the nautical tools, instruments, the whole electronics failed immediately with the break-in of seawater.NARRATOR: Everything including radar equipment, weather faxes, ventilator, alarms, everything malfunctioned. All the instruments short-circuited, the steering gear failed completely. The ship was in distress, not manoeuvrable, but unlike the Caledonian Star the Bremen also lost her engines. The ship and all on board were now in desperate trouble. Unable to power her way through the sea the ship drifted side on to the waves exposing her weakest parts.REINHARD FISCH (Chief Engineer MS Bremen): When the engine failed the ship lay transversely to the sea and the sea rolled crossways to the ship against the big windows of the restaurant.NARRATOR: This was the worst situation possible. The restaurant windows are extremely weak. If they were hit by any large wave water would flood in and the ship would sink.REINHARD FISCH (WITH TRANSLATION): We would have capsized. It would have broken through or smashed the windows.NARRATOR: It was now a race against time. To turn the ship away from the waves they desperately needed to restart the engine, but the starter generator was in pieces on the floor. If they couldn't start the engine the ship and everyone on her was doomed.REINHARD FISCH: We came from the Antarctic and had nearly zero degree water temperature and the air temperature was the same. In those high sea conditions it wouldn't have been possible to put lifeboats of life jackets or life rafts in the water. As well as that, the passengers we sail with aren't the youngest anymore. I doubt any of us would have survived.NARRATOR: So in dark, rolling seas they set to repairing the engine. All the time the waves were smashing against the windows and then they got lucky. The engine finally started.REINHARD FISCH: Then for the first time I had hope we would make it. There are wonderful moments when you know everything works normally again.NARRATOR: Both the Caledonian Star and the Bremen were fortunate to survive, but their experiences challenged everything known about freak waves. There are no currents or local conditions to cause rogue waves in the South Atlantic. According to traditional theory such waves should be incredibly rare, yet here were two within days of each other, so what was going on? Science mobilised every technology to solve the mystery. Using a new radar satellite Suzanne Lehner of the German Aerospace Centre began searching for freak waves around the globe.DR SUZANNE LEHNER (German Aerospace Centre): Now with these radar images you can really see the individual waves. You can see wave lengths, wave directions, wave grouping.NARRATOR: The European remote sensing satellite travels across the ocean using highly sensitive radar to get a detailed picture of the sea's surface. it can pick out individual rogue waves from anywhere in the world.SUZANNE LEHNER: What we get is an image like this one. This is actually the radar image with the highest wave we found on all of our 30,000 images we analysed. This is a 30m wave here. The high crest followed by very low trough.NARRATOR: This is exactly the size of wave which hit the Bremen and the Caledonian Star, the sort of wave that science said was practically impossible and in just three weeks' worth of data they found over 10 such huge waves out in the deep ocean.SUZANNE LEHNER: What you can see here is this highest wave we found of about 30m - that is colour-coded in red. The next highest waves here are about 27m high waves colour-coded in orange. We find another high wave here in the North Pacific. This is again kind of 26m high wave here. We did not expect to find in this limited amount of time so many of these extreme wave events.NARRATOR: If the satellite data is right it looks as if freak waves occur in the deep ocean far more frequently than the traditional Linear Model would predict. The question is: why? The answer seems to lie in a completely different branch of science. Al Osborne inhabits a strange mathematical world where almost anything can happen. It's the bizarre non-linear world of quantum physics. In this world objects appear and disappear according to one remarkable equation, the Schrödinger equation.AL OSBORNE: The Schrödinger equation, quantum mechanics, we have TV programmes called Quantum Leap and so on and so forth so we all think we know something about that equation. There's a version, however, modified, that describes deep water waves.NARRATOR: Osborne is one of the world's leading wave mathematicians. For 30 years he has been obsessed with the theoretical wave described by the Schrödinger equation. The equation describes a theoretical water surface where huge waves can suddenly leap up out of nowhere, where for some reason normal waves become unstable and grow huge.AL OSBORNE: The physics of the non-linear Schrödinger equation we can see in this simple example. In the beginning it doesn't seen like there's anything happening and we could all just give up and go drink a beer if we wanted. On the other hand we could keep moving forward and maybe something will happen. What we'll see is this central wave here's going to start to grow. It's growing because it's robbing energy from its two, two nearest neighbours so here it's starting to come up, you see it's growing, it's stealing energy from the nearest neighbours and these waves are starting to drop. See how this is coming down here. Look at that decrease and now in its full glory it's a very large wave, it has two smaller waves on each side and two rather deep holes in the sea around the peak.NARRATOR: In Osborne's theoretical world these non-linear waves could grow into monsters, but the idea of waves becoming unstable like this in the real world was so outlandish that oceanographers said it could never happen.AL OSBORNE: If you talk to people who know something about ocean waves nobody was going to take this theory seriously.NARRATOR: Until someone sent him the profile of a wave. It was the one that hit the Draupner oil rig in 1995, the New Year wave.AL OSBORNE For me it changed everything, really changed everything.NARRATOR: The New Year wave looked identical to one of his theoretical non-linear waves.AL OSBORNE: I was flabbergasted, absolutely flabbergasted. It just looked exactly like one of these exotic solutions to the non-linear Schrödinger equation. One of the ones that we threw away over the last 30 years because we said this kind of thing can't happen, this kind of thing is just too strange, yet it just sits there and it looks at you and you have to entertain the possibility that it is a real effect and it might really have something to do with these extreme waves in the ocean.NARRATOR: If Osborne is right, here is the reason why rogue waves occur in the deep ocean. It isn't to do with strange local conditions. It's because waves start to behave in a bizarre non-linear fashion. For some reason they become unstable and start sucking up energy from waves around them.AL OSBORNE: You have what's called a rogue sea. Now mariners have known about this. You look at the sea state in one moment everything just looks random, boring waves that we've known about for a long time, but then one of these waves will come up, they're all there, they're all hiding away, one of 'em will come up, then a little later another will come up, but in-between you won't see them necessarily.NARRATOR: Osborne's theory means that there are two types of wave - the ordinary, stable linear wave and an unstable non-linear monster, a wave that at any point can turn into a rogue.AL OSBORNE: This says that there are really two kinds of waves. Amazing thing. Not the old boring sine waves that we've known about for two centuries, not only those, but there's another kind of wave. It's a really special beast. It hides below the background waves and then comes up every once in a while.NARRATOR: This could then explain what Wolfram saw in the North Sea. It could explain what caused the wave that hit the Bremen and the Caledonian Star and it could explain what caused the large number of waves observed by satellite. It seems that there is a separate population of waves out in the ocean that are higher and more frequent than anyone had thought possible and there's something that makes these waves especially deadly. It's not just their size, it's their shape. The Linear Model used by the shipping industry has always assumed that waves are smooth and gently sloping, so ships are only designed to cope with undulating waves like these, but according to mariners freak waves are very different.GÖRAN PERSSON: It was a vertical wall, it wasn't a sloping wave, it was a vertical wall of solid green water.RONALD WARWICK: I likened it to the white cliffs of Dover. It just looked as though there was this enormous great cliff ahead of us.NARRATOR: Freak waves aren't the smooth, undulating waves ships are designed for. They are so steep they can actually break. It means they can hit a ship with astonishing force.ROD RAINEY: The reason why rogue waves are so damaging is because they're breaking. It's no longer really a wave. It's just a pile of water coming flying at you and it just goes bang.NARRATOR: Engineer Rod Rainey analyses ship damage for the marine industry. He has been calculating the huge forces that these giant breaking waves have on ships compared to normal waves.ROD RAINEY: This ball here represents the force of a three metre classical linear wave hitting a ship. That's a force of about 1.5 tons per square metre. This represents a typical storm wave say 12m high hitting a ship - about 6t/m² and... this represents a force from a rogue wave, that's about 100 t/m².NARRATOR: This force is far greater than most ships are designed to withstand.ROY RAINEY: We've looked very carefully at ships that have been damaged by breaking waves and we are sure that the pressures that you can get over substantial areas are about 100 t/m². Now that compares with what a ship is normally designed for high up on the side which typically about 15. Now just to be clear here 15 t/m² is what it can take without any damage at all. It can take perhaps double that if you allow, if you allow it to dent, but it can't take 100 t/m². That will hole it.NARRATOR: It seems that rogue waves are not only out there, but they are far more powerful than any ship can handle. All the scientific evidence suggests that the old explanation for why the shipping industry loses a ship a week may be inadequate. It may not be just corrosion or pilot error. Some at least must be due to freak waves. It means that at last we can lay to rest some of those mysterious disappearances at sea, like that of the München. As the storm grew on that fateful night in December 1978 the München would have carried confidently on carving through the rising seas, until suddenly out of the darkness there would have loomed a huge 30 metre wall of water.WERNER HUMMEL: The way it most probably goes is that the bow of the vessel is diving into a trough, a wave trough and then before it, it has raised up again the wave is so to say collapsing over the bow and the superstructure and with tremendous force is striking against the front bulkhead hitting the starboard lifeboat and doing the damage which we have seen on the picture.NARRATOR: The wave would have smashed into the bridge just like it did in the Bremen taking out the instruments and engines and rendering the ship helpless. If the ship had turned side on to the waves another wave could have holed her. Water would have poured in eventually plunging the great ship München and everyone on her to the bottom of the sea.
November 23, 1996
Rough math: Focusing on rogue waves at sea
by I. Peterson
In late 1942, carrying 15,000 U.S. soldiers bound for England, the Queen Mary hit a storm about 700 miles off the coast of Scotland. Without warning amid the tumult, a single, mountainous wave struck the ocean liner, rolling it over and washing water across its upper decks. Luckily, the ship managed to right itself and continue on its voyage.
Gargantuan waves, which appear unexpectedly even under calm conditions in the open ocean, have damaged and sunk numerous ships over the years. Now, researchers have identified a plausible mechanism that may account for the occurrence of these rogue waves. Using a mathematical model, they demonstrate that ocean currents or large fields of random eddies and vortices can sporadically concentrate a steady ocean swell to create unusually large waves.
The current or eddy field acts like an optical lens to focus the wave action, says applied mathematician Bengt Fornberg of the University of Colorado at Boulder.
Fornberg and Benjamin S. White of Exxon Research and Engineering Co. in Annandale, N.J., describe their model in a report submitted to the Journal of Fluid Mechanics.
Rogue waves can arise in all oceans. However, their frequency and size are particularly notable off the southeastern coast of South Africa. Every year, a few supertankers and other major vessels suffer severe structural damage while traveling southward along a standard route from the Middle East to the United States or Europe.
The vessels boost their speed by taking advantage of the strong, south-flowing Agulhas Current, which skirts the South African continental shelf. Depending on the prevailing winds, this current often meets a steady incoming wave swell nearly head-on. The interaction of wave and current reduces the spacing between the waves and changes their direction.
Applied mathematician Marius Gerber of Stellenbosch University in South Africa recently showed that changes in wave direction forced by a narrow, fast current can raise wave heights considerably in certain areas of the current. His calculations also suggest that such waves would have a distinctive shape, displaying a steep forward face preceded by a deep trough. Mariners who have experienced rogue waves have described such troughs as "holes in the sea."
This focusing mechanism is very likely responsible for the freak, isolated waves encountered in the Agulhas Current, Gerber argues. Such focusing could also occur within or near the Gulf Stream in the North Atlantic.
Fornberg and White have now shown, in principle, that similar focusing can take place when an ocean swell of regularly spaced waves traverses an area of random current fluctuations. They can compute the probability of particularly intense wave action and the formation of rogue waves in different regions of the field. These probabilities depend on how far the waves of the ocean swell have traveled through the eddies rather than on the detailed structure of the eddies themselves.
Exploratory work on the formation of rogue waves at sea and in currents has been largely theoretical so far. The chief problem is the extreme shortage of reliable, complete oceanographic data on this phenomenon to test the mathematical models.
The waves arise rarely, although they're very notable when encountered, Fornberg notes.
The ultimate goal of the researchers is to develop models to predict the location of danger areas and to forecast the occurrence of rogue waves, which would allow ships to proceed safely yet take advantage of ocean currents.
The Agulhas Current is a prime target for such an effort. The latest incident in the area occurred earlier this month, when a cargo ship with 29 people aboard sank after being hit by a wave, presumably a freak giant.
30 November 2003
Contact: Phil Anderson or Peter Scott +44 (0)19 1232 5221
Increasing proof of rogue waves could help to defend ship owners
Increasing evidence and awareness that rogue waves over 30 m high can occur randomly throughout the world’s oceans could increase shipowners’ chances of defending cargo claims after encountering such waves, according to the North of England P&I club.
‘Shipowners and their P&I clubs have historically found it difficult to defend cargo claims after being hit by freak waves as they are impossible to prove with conventional linear wave modelling,’ says senior claims executive Peter Scott. ‘However, recent research and publicity – not least in a BBC Horizon programme called Freak Wave that was first broadcast last November – means we are now better placed to use a ‘perils-of-the-sea’ defence.’
A ship entered in the North of England was recently hit by a freak wave in the middle of the Indian Ocean, but was able to reach port. However, the hull was breached and some cargo was damaged – but cargo interests alleged this was because the vessel was structurally unsound and therefore unseaworthy.
In preparing to defend the claim the North of England commissioned a technical analysis of the hull damage, which revealed the water pressures experienced were significantly greater than the hull design pressures. However, it soon became apparent that the costs required to test the technical evidence in court would be disproportionate to the value of the claim, so settlement was reached.
‘However, for a larger claim, we now feel confident we could assemble sufficient technical proof that a rogue wave did exist and was the primary cause of cargo damage,’ says Scott.
The BBC programme reported that during a brief, three-week radar satellite study, the German Aerospace Centre found a total of 10 monster waves around the world, ranging from 26 m to 30 m in height. As the programme concluded: ‘If the satellite data is right, it looks as if freak waves occur in the deep ocean far more frequently than the traditional linear model would predict.’
The programme added that the Schrödinger equation from quantum physics shows it is theoretically possible for an unstable, rogue wave to form anywhere in the oceans by absorbing energy from adjoining waves.
Shipowners attempting to defend rogue wave damage claims will nevertheless need to show that structural maintenance has been carried out properly and carefully. ‘In particular they will need to prove that any diminution of steel is with both the classification society’s limits and the limit that would be adopted by a prudent owner,’ say Scott.
Was ship victim of a freak wave?
Aug 21 2003
By Andy Lloyd, The Evening Chronicle
Freak 100ft waves could have caused one of the North East's worst shipping disasters.Lawyers representing families of fishermen who died on board The Gaul off the coast of Norway in 1974 say a wave the height of an office block could have caused its mysterious sinking.It comes after a BBC documentary revealed new scientific evidence which proves that breaking walls of water - like in Hollywood blockbuster The Perfect Storm - can wipe out the biggest ships.Until recently, stories of massive waves claiming one ship a week were dismissed as mariners' myths - until they were captured by scientists on satellite.Six victims from Tyneside were among 36 fisherman on board the supertrawler when it sank in an icy storm. A public inquiry next year will re-open the investigation into how it happened.Barry Tindall, legal clerk to Hull-based Max Gold solicitors, said: "Bad weather has always seemed to be the most likely explanation and a freak wave like this is plausible."The conditions in the sea were very bad when The Gaul sank and other boats were laid up in port"There were theories at the time that it had taken a torpedo or rammed by a submarine, but these have been ruled out by the underwater evidence gathered recently."These large waves can take out ships' bow windows and, although these were intact in The Gaul, it is possible it could have been hit side-on while turning."Tests are being done on giant water tanks in Holland to recreate the conditions and the structure of The Gaul as part of the new inquiry."An alarming series of ocean-going disappearances of world-class vessels with unblemished safety records have been dismissed as human error or poor maintenance, with scientists believing a 30-metre swell could only happen once every 10,000 years.But oceanographers had to think again on New Year's Day, 1985, when a 26-metre wave was measured hitting the Draupner oil rig in the North Sea off Norway, close to The Gaul's last known fishing grounds.Last month human remains from three men, recovered and identified from the vessel through DNA, were released for burial - including those of third engineer James Wales, 30, from Rosetree Crescent, North Shields, factory chargehand Stan Collier, 40, and acting first mate Maurice Spurgeon, 38.In 1974, a formal investigation into the disaster decided the vessel capsized and foundered in heavy seas, but the recent discoveries prompted the Government to re-open its inquiry.The six Tynesiders killed were Ronald Bowles, 22, of Wallsend, Jim McLennan, 18, James Woodhouse, 45, James Wales, 30, Neil Petersen, 51, and chief engineer John O'Brian, all of North Shields.Aubrey Bowles, brother of Ronald Bowles, said: "Bad weather was probably to blame, but we will have to wait for the inquiry to discover just how bad."Weather can strike terrorFreak waves at sea - unlike tidal waves which hit coastlines after earth tremors - are caused when one wave sucks from others around it, becoming a towering monster.Freak breakers are thought to have been responsible for the loss of the German merchant ship, the cargo vessel Munchen in December, 1978.Only a few badly-damaged pieces of the ship were found and a maritime court concluded that bad weather had caused an `unusual event'.And in March, 2001, both the Bremen and Caledonian Star had lucky escapes when they were both disabled by 30-metre waves which smashed over the ships carrying hundreds of tourists across the South Atlantic.Since 1990, 20 vessels have been struck by waves off the South African coast that defy predictions, causing panic among shipping operators.Wave mathematician Al Osborne used quantum physics used global satellite surveillance to analyse rogue waves radar and spotted dozens around the globe - including off the coast of Norway.