Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
Earth Science

Scientific Cruise Meets Perfect Storm, Inspires Extreme Wave Research 107

Posted by Unknown Lamer from the creative-punishment-for-copyright-infringers-discovered dept.
An anonymous reader writes "The oceanographers aboard RRS Discovery were expecting the winter weather on their North Atlantic research cruise to be bad, but they didn't expect to have to negotiate the highest waves ever recorded in the open ocean. Wave heights were measured by the vessel's Shipborne Wave Recorder, which allowed scientists from the National Oceanography Centre to produce a paper titled 'Were extreme waves in the Rockall Trough the largest ever recorded?' It's that paper, in combination with the first confirmed measurement of a rogue wave (at the Draupner platform in the North Sea), that led to 'a surge of interest in extreme and rogue waves, and a renewed emphasis on protecting ships and offshore structures from their destructive power.'"
This discussion has been archived. No new comments can be posted.

Scientific Cruise Meets Perfect Storm, Inspires Extreme Wave Research More

Scientific Cruise Meets Perfect Storm, Inspires Extreme Wave Research

Comments Filter:

  • 2 theories at once (Score:3, Funny)

    by Anonymous Coward on Monday April 16, 2012 @11:06PM (#39707379)
    This scientific cruise also proved that the only kind of cruise where nobody gets laid is a "scientific cruise"

  • How high were the waves?!? (Score:5, Informative)

    by cplusplus ( 782679 ) on Monday April 16, 2012 @11:15PM (#39707423) Journal
    I only RTFAs to find out how high the waves were - it turns out they were up to 29.1 meters (95.5 feet).

  • Rogue waves (Score:3, Funny)

    by gstrickler ( 920733 ) on Monday April 16, 2012 @11:23PM (#39707453)

    Outlaw them and put out a bounty (or a Bounty?)

  • 2006 (Score:5, Informative)

    by Anonymous Coward on Monday April 16, 2012 @11:32PM (#39707491)

    The article was published in 2006. How is this 'new?'

    • The article was published in 2006. How is this 'new?'

      I guess it's some sort of tie in with the 100th anniversary of the Titanic making it almost all the way across the Atlantic.

      • The wave was so high that the ship did a loopty-loop, causing a rift in time where they just ended up here. The same phenomenon can be seen if you can swing high enough on a swingset to go around once

    • The article was published in 2006. How is this 'new?'

      Well, I agree with your point. But six years is a good time to let scientific papers simmer. Less than that is not enough time for other scientists to evaluate the correctness and value of some paper.

    • Re: (Score:1)

      by Anonymous Coward

      Many researchers were lost during the peer-review of this paper.

    • 2006? Wasn't that around the time a rogue wave was recorded on The Deadliest Catch?
    • Data collected in 2000. Paper published in 2006. Reported in /. in 2012. The pace of good science is slow and deliberate.

  • For those that are interested... (Score:5, Interesting)

    by Anonymous Coward on Monday April 16, 2012 @11:43PM (#39707553)

    look up Schrodinger wave equations and apply them to ocean waves. You will get 30+ meter tall waves with a trough next to the "wall" of water, (the wave is tall and narrow - like a wall). This trough adds to the great difficulty in surviving one of these waves. Ships that are designed to withstand forces of 10 tons/m2 have to content with 10 times that force. I believe there was a study in which someone, (don't remember her name :( ) mapped the entire earth over a two week period and found something on the order of 20 of these waves. Fascinating stuff.

    • Re:For those that are interested... (Score:5, Informative)

      by phantomfive ( 622387 ) on Tuesday April 17, 2012 @02:21AM (#39708089) Journal
      Oh yeah, just found it [bbc.co.uk]. They found about 10 giant waves.

    • Re: (Score:1)

      by Anonymous Coward

      FYI the Schrodinger wave equation does not describe ocean waves. Water waves are described by the Navier-Stokes (N-S) equations. Turbulence models fall out of N-S, however only electrons sometimes fall out from Schrodinger :)

      • There is a non-relativistic version of the Schrödinger equation. Some theories attempt to explain rogue waves in the open sea using these non-linear equations as a model, because the distribution of wave heights that would result from the linear model substantially underpredicts the occurrence and size of rogue waves.

      • Re: (Score:1)

        by Anonymous Coward

        The nonlinear Schordinger equation is one of the many various equations that can be used to describe the behaviour of water waves in various regimes, with a tiny bit about it on Wikipedia here [wikipedia.org]. Although the NLS is mostly used for behaviour of the envelope of deep water waves, which means you can show soliton based rouge wave like behaviour, but not say much about trough to peak steepening as in the grandparent post.

        The set of equations and theories used to model nonlinear water waves is quite diverse, wit

  • Dead men tell no tales (Score:3)

    by WaffleMonster ( 969671 ) on Monday April 16, 2012 @11:52PM (#39707605)

    For those looking for more details about this voyage http://eprints.soton.ac.uk/294/ [soton.ac.uk]

  • Specifically in 1998, a 120ft wave off the east coast of tasmania http://www.swellnet.com.au/news/124-a-short-history-of-tasman-lows [swellnet.com.au]

    • Since extreme waves were not the subject of their expedition, they had not read all the prior literature.

    • Re:I thought bigger waves had been found... (Score:5, Interesting)

      by TapeCutter ( 624760 ) on Tuesday April 17, 2012 @01:48AM (#39708017) Journal
      The Tasman sea is notorious for rouge waves. Many moons ago I worked a fishing trawler in Bass Straight, I never saw anything like 120ft but the regular waves were tall enough that the radar was blocked by the peaks when the boat was in a trough, I'm guessing the radar mast was about 30ft above the water line. A lot like riding in a giant roller coaster carriage really, slowly climb up one wave, crest, then race down the other side and watch the bow dig under the next one, throw the water over the wheel house as the bow pops up to the surface, and starts the next climb. From what I've heard, the problem with rouge waves is not so much their height but the fact that they are too steep to climb.
      • Wow, that is incredibly exciting.
        • I detect a hint of sarcasm but to be honest it was downright fucking scary the first trip but after a few trips it became as exciting to me as an old fashioned roller coaster is to the guy who stands up on it all day operating the brake. Although a stingray the size of a family dinner table flapping about on an 8X12 deck was never boring.
          • No sarcasm at all. If the human lifespan weren't so short I would definitely consider going down and trying it out for a few years. I don't know about that stingray thing, though. I know people who go ocean kayaking but that's nothing in comparison.

          • Re: (Score:2)

            by tlhIngan ( 30335 )

            I detect a hint of sarcasm but to be honest it was downright fucking scary the first trip but after a few trips it became as exciting to me as an old fashioned roller coaster is to the guy who stands up on it all day operating the brake. Although a stingray the size of a family dinner table flapping about on an 8X12 deck was never boring.

            Waves are never boring, especially big ones. The key is to cut through them - if you let them hit the side, you risk capsizing. The only way to do this is engine power (run

            • Re: (Score:2)

              by serbanp ( 139486 )

              Does this mean that the "the Perfect Storm" depiction of how the Andea Gail sunk was technically inaccurate? In that film, the ship went with its bow straight into the freak wave but could not reach the top and fell over.

            • Yep, it's a lot like a plane, if engine is fucked, gravity takes over and you basically fall of the wave..
    • That article claims 42.5m is 120 feet - it's actually 140 feet. The wave was probably recorded as 120 feet and someone mangled the conversion rather than the other way round.

  • Weird (Score:3)

    by Sarten-X ( 1102295 ) on Monday April 16, 2012 @11:53PM (#39707611) Homepage

    Rogue waves: Demonstrating yet again that reality is a fascinatingly weird place.

    • Rogue waves: Demonstrating yet again that reality is a fascinatingly weird place.

      And we don't understand our planet as much as we think. We are always focused on exploring strange new worlds, to seek out new life and new civilizations, to boldly... um, you get the idea, but look, there's new things happening on our own planet. How can we understand new planets when we don't understand the one we are on? Not saying never explore space, just saying maybe we should focus on what we have.

      • Re: (Score:1)

        by Anonymous Coward

        How can we understand new planets when we don't understand the one we are on?

        How can we understand this planet when we have nothing to compare it to?

        Rethorical questions only caters to peoples emotional response but they don't make much of an argument.

      • Reminds me of the TV show seaQuest... for almost a whole season, they had interesting episodes based around real weirdness in the oceans.

        What fascinates me even more is the emergent behavior observable in simple systems, such as growing crystals, diffusing liquids, convection currents... all of those delightfully complex results from simple principles. There's beauty in the result, and simplicity in the process.

    • Re: (Score:1)

      by Anonymous Coward
      Although the paper might have spurred interest in rogue waves, the wave in the paper linked in the summary wouldn't really be considered a rogue wave. Usually a cut-off is arbitrarily picked at 2 times the significant wave height (the average of the highest third of waves). In this case, the wave was about 1.5 times the significant wave height. Statistically speaking, you would expect about 1 in a 100 waves to be 1.5 times the wave height, just from the mixing and constructive interference of waves, whil

  • Big waves (Score:4, Interesting)

    by MarkRose ( 820682 ) on Tuesday April 17, 2012 @12:06AM (#39707665) Homepage
    Waves over 20 m (60 ft) tall are actually pretty common in some places. My dad is senior keeper at Triple Island Lightstation [fogwhistle.ca], located just off the BC coast. In severe winter storms, the waves will often crest over the square part of the building, which is about 20 m above sea level. This January, one such wave blew in a storm window on the top floor -- several tons of water will sometimes do that. The building stays up because it's constructed with 2 ft thick rebar concrete walls.

    • Re:Big waves (Score:5, Informative)

      by tirerim ( 1108567 ) on Tuesday April 17, 2012 @12:39AM (#39707811)
      TFA is talking about waves in the open ocean, though. Waves get higher when they reach shallower water, so the 20 m waves you're talking about would have been significantly smaller in the open ocean -- which makes 29 m open ocean waves that much more impressive.
    • Nice traditional exterior, but sad to see the drop ceiling [lighthousememories.ca] on the interior. At least the wood floor is original.
    • Interesting link but some of the text is reminiscent of Julian and Sandy (http://en.wikipedia.org/wiki/Julian_and_Sandy) from "Round the Horne", I mean, "The Triple Island light was built to guide mariners through the rocky waters of Brown Passage, on their way to the port of Prince Rupert.", I ask ya!
  • It's interesting how often myth and legend end up being scientific fact. There has been talk since sailors took to the sea of rogue waves that reached a 100' or more. Science has been confirming these myths in recent years. Most myths have an element of truth in them. On the practical side it's a serious concern since surviving a 100' rogue wave is not something all sea worthy ships can do yet they can face them without warning. I read years ago the theoretical limit was twice what has been recorded so the

  • The paper is from 2006, and describes a wave observed in 2000.

    Satellite-based radar altimeters produce a lot of data about wave height world wide, but they don't, apparently, have quite enough resolution yet to see this kind of thing. A view of such waves from above, over a few minutes, would tell us a lot. Is it an intersection of two or more waves? How far does it travel? How long does it persist?

    The U.S. Navy has put considerable effort into answering questions like that.

  • bad statistics (Score:4, Interesting)

    by Tom ( 822 ) on Tuesday April 17, 2012 @03:24AM (#39708283) Homepage Journal

    What has fascinated me about freak/rogue waves is that sailors have known about them for decades if not centuries, but scientists were telling them it can't be.

    And the reason is badly understood statistics. I've recently read Black Swan, and that gave me a few new concepts to work with, but the basic idea is exactly that: We don't really have a good understanding of statistics and probabilities, especially about extremely low probabilities in big numbers.

    Or, as Tim Minchin put it: One-in-a-million things happen all the time.

    And it's not just in the oceans. The entire financial crisis was caused by the people in charge taking huge (but low probability) risks, ignoring that once enough people have taken enough of those "low probability" risk, they become very likely to actually happen.

    Freak waves are cool because they are in the gray area between the normal distribution and the really freaky - thus they happen often enough that they are rare, but not bigfoot-rare. We can actually study them.

    • Re: (Score:3, Interesting)

      by edxwelch ( 600979 )

      There's an interesting article about that, here: http://www.bbc.co.uk/science/horizon/2002/freakwave.shtml [bbc.co.uk]
      Apparently, there are two scientific models, linear, which says freak waves are impossible and Quantum physics which says they are possible.

      • Re: (Score:2)

        by Tom ( 822 )

        The problem is that a gaussian approach to the numbers assumes that random fluctuations will even out. But the equations used in quantum physics allow for waves to combine, and that's what is happening - interference, just not between 2 waves as in the double-slit experiment, but between dozens or maybe hundreds of waves.
        This article here: http://dev.physicslab.org/Document.aspx?doctype=3&filename=PhysicalOptics_InterferenceDiffraction.xml [physicslab.org] shows towards the bottom how massive peaks you can get with mult

        • Re: (Score:1)

          by Anonymous Coward

          Linear wave theory allows for interference and combining of waves (that is kind of actually one of the major properties of linear theories in a lot of situations). The statistics on linear theory waves (which ends up being a Rayleigh distribution, not a Gaussian) is what says that waves much larger than those around it are very unlikely. What nonlinear theories add is not just overlapping like interference, but soliton like solutions, where a single wave or small wave train much larger than neighboring wa

          • Re: (Score:2)

            by Tom ( 822 )

            Thanks, AC. In 12+ years of /. this was one of the most informative AC comments I've come across.

  • We have bigger waves in Texas!

  • Halsey's "second" typhoon, June 1945 (Score:5, Interesting)

    by dtmos ( 447842 ) * on Tuesday April 17, 2012 @06:09AM (#39708623)

    My uncle retired as a US Navy Captain. For many years he had two photographs displayed in his house, which he ascribed to Admiral "Bull" Halsey's "second" typhoon [navy.mil], in June 1945. At that time my uncle was an ensign, assigned to a destroyer, and on his first sea voyage.

    The two photographs were of a sister destroyer. In the first photograph, all one sees is a giant wave, with the bow of the destroyer sticking out of one side, and the stern sticking out of the other. The middle of the ship, including the masts and superstructure, is submerged and not visible.

    In the second photo, taken a few seconds later, the middle of the ship is now visible, but both the bow and stern are now submerged in the wave train. And as a kid, the part that fascinated me the most: You could see an air gap below the middle of the ship, between the ship's keel and the wave trough below.

  • I'm surprised I can't get for my boat (or raft) a platform with accelerometers that operates a hydraulic piston to compensate for wave action. It might need some lateral actuator too, as wave motion is circular. But it might not, if the light floats slide along the surface as the piston pushes down on them keeping the heavy inertial payload in place.

    Just accelerometers, hydraulic pistons, and DSP. Big bonus points for a device that harvests that energy moving through the site to power the hydraulics.

    Really

Slashdot Top Deals

Technology is dominated by those who manage what they do not understand.

Close