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Software Transportation Science

New Software Could Warn Sailors of Rogue Waves 131

Reservoir Hill writes "Sailors have been telling stories for centuries about monstrous ocean waves that tower over a hundred feet in the air and toss ships around like corks. While these were once dismissed as nautical myth, but a few years back synthetic aperture radar from ESA's ERS satellites helped establish the existence of these 'rogue' waves and study their origins. Such waves were far more common than anyone had expected. Now a researcher in Madrid has developed software that can detect rogue waves from radar images, with the possibility of providing advance warning to ships at sea. The software uses a mathematical model to evaluate and process the spatial and temporal dimensions of waves inferred from the interaction between the radar's electromagnetic energy and the sea surface. The result is displayed in a color-coded image."
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New Software Could Warn Sailors of Rogue Waves

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  • by SmallFurryCreature ( 593017 ) on Saturday November 24, 2007 @06:50PM (#21465877) Journal

    The entire trick to surviving these waves seems to be not catch them from the side. If this warning comes in enough time to turn the ship to face the wave at the safest angle then the ship stands a better chance.

    Even if the ship is destined to sink, this might give the crew more time to get to the liveboats, some modern ones are almost like subs so that no matter the wave, they can survive because they always right themselves and are closed so they can't fill with water and are to small to be broken up.

    I have no idea exactly how much warning a ship can get with this, but as you can see from the pictures supplied and the stories in the article these waves can be survived. Perhaps a person with some experience can tell if the sudden sinkings could be down to the ship catching the wave at the wrong angle.

  • by Dunbal ( 464142 ) on Saturday November 24, 2007 @07:25PM (#21466097)
    What about numerous UFO observations, Loch Ness etc? are you suggestion those should be regarded as proof of existence since there have been numerous observations and murky photographs? Science works by being skeptical, yes it can take decades for something to be acknowledged and that might be bad but taking every observation as proof would be worse.

          Especially since the original perpetrator of the "Loch Ness Monster" hoax publicly admitted to it about 20 years ago in the UK, just before dying. Along with his admission was an apology, and what made him cough up the truth was seeing all the boats gathered with sonar equipment to finally, once and for all, put this myth to rest. He said he was ashamed that so many people had invested so much money for this.

          But people love to believe bullshit, and even though this made the news in the UK at the time (I watched it), people still perpetrate the "Loch Ness Monster" BS. Don't even get me started on UFOs.
  • by Anonymous Coward on Saturday November 24, 2007 @08:00PM (#21466291)
    Wiki has a good article: http://en.wikipedia.org/wiki/Rogue_wave_(oceanography) [wikipedia.org]

    For the entirety of my career (33 years) scientists have accepted the existance of rogue waves. The problem is that there were few measurements. That is remarkable given the number of instruments we put into the water every year. As the Wiki article points out there are several competing theories of how the waves happen. It is possible that more than one of these theories is correct depending on local conditions. For instance, in the middle of the ocean, such waves might be caused when waves coming from several directions all achieve maximum amplitude at the same place and time. Nearer to shore, they may be caused by the shoreline focusing waves like a parabolic reflector.

    I'm not a scientist but I have spent a lot of time working with them and I have never heard one deny the existance of rogue waves.
  • Re:Tsunami (Score:5, Informative)

    by RogueyWon ( 735973 ) * on Saturday November 24, 2007 @08:01PM (#21466305) Journal
    Not necessarily.

    Tsunamis and Rogue Waves are very different. If you'll forgive the generalisations; Tsunamis are mostly caused by events which result in the displacement of large quantities of water, such as earthquakes, landslides and asteroid impacts. They travel for hundreds, or even thousands of miles and cover a wide area of the sea. Their speed and height is heavily dependent upon the depth of the water - in deep water, they can travel at hundreds of miles per hour, but, crucially, may be no more than a few inches high. Ships can pass over them without ever realising they've done so. When they hit shallower water, the wave grows. However, what does the damage with tsunamis is not the height of the wave, per se, as the sheer amount of water behind it. The Boxing Day Tsumani that caused so much devastation a couple of years ago was only about 30 feet high when it hit land in many places - well within the range for a storm wave at the high end of the normal scale. However, the "wave" you see with a tsumani is just the front end of a huge body of water, with a vast amount of momentum. When a tsunami hits, it is as though the water level in the area affected has just jumped up to the height of the top of the incoming wave. This is obviously devastating, as it causes massive flooding and hugely powerful movements of water that can go miles inland.

    Rogue waves, on the other hand, are essentially "surface" waves. The causes vary (winds running counter to currents is one cause, but there are others), but they have, in most respects, more in common with a storm wave than a tsunami. Their shape resembles that of a "breaking" wave when it hits the shore (although this is quite different from the "rolling" shape of a wave in the middle of the ocean) and there is no huge mass of water behind the wave itself. However, the height of a rogue wave is truly terrifying - essentially up to 100 feet - twice the size of the largest storm waves you could normally expect to encounter. Rogue waves are so dangerous to ships because their size and shape ensures that the pressure they exert on a ship they hit is way beyond what would normally be expected and designed for. However, they are rare and short-lived. The waves will usually be no more than a mile or two long and will run for about 10 miles or so on average.

    The system discussed in TFA appears to be a radar based system. It works by picking up very, very large waves on radar and warning the crew of a ship caught in the path (giving them time to prepare and turn the ship to meet the wave). However, tsunamis would not show up on radar in mid-ocean and only the ultra-rare megatsunamis (which can occur either in an enclosed bay which suffers a massive land-slide, or on a broader scale when a truly massive asteroid impact or landslide occurs) would ever reach the height of a freak wave. Tsunami detection is likely better left to seismic monitoring and pressure sensors.
  • by flyingsquid ( 813711 ) on Sunday November 25, 2007 @05:12AM (#21469621)
    Speaking as a scientist, and as a sailor with a couple decades worth of experience on the North Pacific, go to hell.

    Yeah, science is pretty far from perfect. We scientists can be arrogant, quick to trust our theories and to disregard experience, and we make mistakes. We are, in other words, human. But scientists have also given us vastly improved navigational technology. Radar lets you see where the land is, through darkness, rain, and fog, to avoid hitting coasts and other ships. Loran, and now GPS, gave ships the ability to see precisely where they are. Ship-to-ship radio communication made it possible for ships to radio for help when they were in distress. EPIRBs (emergency position indicating radio beacon) allow ships to send distress calls over a satellite network to the Coast Guard and send precise information on their location.

    The end result? Being on the water isn't safe, it never has been, and it never will be. The ocean is an unpredictable and dangerous thing. But thanks to these scientific advances, it's much, much safer today than it was just twenty or thirty years ago.

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