Freak Wave - transcript
NARRATOR (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.