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Freak waves are real: A lesson in objectivity

  1. Jul 23, 2004 #1

    Ivan Seeking

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    Long treated as myth and folklore, this is just one of many such rerorts that seem to confirm at least some mariner's reports of freak waves. From what I can tell, the jury is in: Freak waves are real. There is no question that they exist.

    http://www.esa.int/export/esaCP/SEMOKQL26WD_index_0.html

    So, here we have an example of something long dismissed as lies and myth in spite of centuries of stories from sailors. I think this is a shining example of how human testimony must be considered. No matter how unlikely something may be, certain elements of long term patterns in human testimony can often be trusted; not as scientific evidence of course, but I think for guidance as to what may and may not be real. Often, these sorts of things are based in fact and not just fanciful tales like those of drunken sailors. The problem I think is not whether there is a grain of truth in any myth, since I think most are rooted in fact, the question is, what is the proper context and interpretation for a given myth? In this case the proper interpretation was a literal one. I suspect this is an unusual outcome. Normally I would expect that we need to interpret the myth to a much greater degree.
     
    Last edited: Jul 23, 2004
  2. jcsd
  3. Jul 23, 2004 #2
    A twenty foot freak wave hit Daytona Beach Florida a couple of years ago. Fortunately it happened at night and no one was hurt. Another natural occurence that was long deemed to be a sailor's myth was the giant squid.
     
  4. Jul 23, 2004 #3

    russ_watters

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    Yeah, but its probably a few hundred years since they were considered a nautical myth.
     
  5. Jul 23, 2004 #4

    Ivan Seeking

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    A few hundred years...please. These were only discovered by accident.
     
  6. Jul 25, 2004 #5
    I don't believe rogue waves where ever really dismissed as myth and folklore.
    They have been generaly accepted in the scientific comunity for quite some time
    Just so happens the wonders of science happened to image one from a satellite.
    The author talks about scepticism in the scientific and makes one think that all of the scientific comunity have never believed they existed. Every scientific work has its sceptics.
    The author does not tell us what the sceptics say in their papers just that large deviations should only occur once every 10000 years. It does not say how large the deviations are.



    That first image with that freighter was taken in 1980 off the coast of Durban and was estimated to be 5-15 metres high. (prob from the trough)
     
  7. Jul 25, 2004 #6

    Ivan Seeking

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    Then consider this, rogue waves are now considered a genuine threat to shipping and oil platforms. Research is now underway to understand these waves. Where is the research prior to the last five or ten years? How many papers have been published on this subject? This is the best measure of acceptance. If this threat is as signficant in dollars as now described, why didn't we explore this issue in detail long ago?

    I think the proof of my statements is found the previous lack of interest and funding for research. Suddenly freak waves are getting lots of press and attention from the scientific community.
     
    Last edited: Jul 25, 2004
  8. Jul 25, 2004 #7

    Nereid

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    Things are probably more nuanced than this rather b/w depiction Ivan.

    Before the ESA work, there was surely widespread acceptance that, occassionally, very big waves were seen. For doing research however, the difficult parts were 'occassionally' and 'very big'; in both cases, the generally accepted understanding was well aligned at the qualitative level (everyone agreed that 'very big waves' 'absolutely must' happen 'occassionally'), but quantitative data were either poor or scarce. Further, the cost of a research project to nail down the phenomenon quantitatively probably didn't seem worth it (return on research investment $ and effort) to those who could've done it (scientists) or paid for it (ship owners, oil companies, etc).

    With the EDA data, some initial 'survey' work can be done at almost zero incremental cost, and a biz case for an investment in further research becomes clear - IF the waves do occur at the frequency implied by the preliminary ESA data THEN a better understanding of them can be expected to save us $$ (range, not a single number); as the research will cost only $$ (range), the ROI is good.

    It may be educational to compare the history here with that of sprites.

    Interesting terminology, is it 'freak waves' or 'rouge waves' :smile:
     
  9. Jul 25, 2004 #8

    Ivan Seeking

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    Do you have any information to support this position? Where is the information that tells me that this was accepted as a genuine phenomenon?

    I find it amusing that whenever something like this is discovered as true, the next statement to be expected is that we always knew they were there. I have seen no reason to believe that anyone except seaman accepted this phenomenon as genuine. Every explanation that I ever heard assumed that an earthquake, or unusual weather, or a landslide produced these waves; until a few years ago. The interview that I saw with the scientist who discovered freak waves on satellite images was not looking for them. He just noticed them. ESA is only following up on this previous work.

    I have always heard them called rogue waves. Freak waves seems to be a more recent term but I don't know for sure.
     
    Last edited: Jul 25, 2004
  10. Jul 25, 2004 #9

    Ivan Seeking

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    In fact I think I realize the problem here. Sure, we have always known about large renegade waves; that is waves that exist for a reason that we understand. Rogue waves seemingly have no source. In a nutshell, this is the objection that was made by scienctists when asked: Waves don't spontaneously appear without a cause. As is usual, we just weren't imaginative enough.

    Can anyone show me one paper more than ten years old that uses wave mechanics to predict large rogue waves at sea. This effort would not have required tremendous funding.
     
    Last edited: Jul 25, 2004
  11. Jul 25, 2004 #10

    Ivan Seeking

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    One last thought here. Even if all of the objections made here are correct this does not detract from my original point. My point was that just as with ghosts, UFOs, ESP and certain other phenomenon [not all], we have centuries of human testimony that freak waves are real. On a large scale, that is to say over a very long time and with many encounters, it turns out that the human was reasonably reliable as a data recorder; in spite of the fact that we had and have no good explanation for their accounts. Why should we assume this is not true for UFOs and other phenomenon that meet relatively the same historical criteria?
     
    Last edited: Jul 25, 2004
  12. Jul 25, 2004 #11

    Nereid

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    I think there are two different things being somewhat conflated here Ivan (true, they're to completely independent, but more so than your posts would suggest).

    1) Acceptance of observations of large waves: undoubtedly some observations were or marginal quality; equally some were not. AFAIK - and this is a long way from the area of science I have some familiarity with - no one doubted there are good observations of large waves.

    2) Satisfactory explanations of each particular observation of a large wave. This is the part which seems to have changed; a recognition that previous explanations are insufficient to account for the (new, ESA) data.
     
  13. Jul 25, 2004 #12

    Ivan Seeking

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    I agree. As I understand it, conventional explanations have always been assumed in spite of objections that these explanations do not account for what was observed. It was always assumed when needed that specific details, such as the size of the wave, or the direction from which it came were in error, which made possible some conventional assertion that was probably never tested. In the extreme, I remember hearing of one case in particular in which the loss a ship was attributed to human error in spite of accounts from the crew that a rogue wave destroyed the ship.
     
    Last edited: Jul 25, 2004
  14. Jul 25, 2004 #13

    Ivan Seeking

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    My apologies. It never ocurred to me that the meaning of "Rogue Wave" was not clear. A Rogue wave is a very specific sort of wave that allegedly defies all conventional explanations. A typical account might say that a storm and the swells approached from the north when suddenly a single large wave from the east destroyed the ship. There is nothing east of the ship that could produce a large wave.

    Edit: I think the term applies equally well to inordinately large waves within the standard movement of ocean swells. For example, the swells are running 5 to 7 feet when a 25 foot wave suddenly sinks or swamps the ship.

    I am now a little suspicious that large releases of gas caused by methane hydrate deposits may account for some rogue waves. I don't know if this is possible or not.
     
    Last edited: Jul 25, 2004
  15. Jul 25, 2004 #14

    selfAdjoint

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    solitons

    I think it is more likely that the rogue waves are solitons.
     
  16. Jul 25, 2004 #15

    Ivan Seeking

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    Nonlinear wave dynamics is now thought to explain some rogue waves.
     
  17. Jul 26, 2004 #16

    russ_watters

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    That was all I was trying to say - could you take an uneducated sailor's word for it in 1800 that his ship was capsized by a massive wave in otherwise calm seas? Probably. He doesn't need to know about undersea earthquakes or complex wave mechanics to know that - it doesn't much matter to him where the wave came from. Where the wave came from could well be more complex than scientists thought 10 years ago, but thats a separate issue from accepting that big waves exist.

    I don't consider this to be anywhere near the category of [ET]UFO's.
     
  18. Jul 26, 2004 #17

    Ivan Seeking

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    Yes sorry about that. I assumed that the meaning was clear, really for no good reason.
     
  19. Jul 26, 2004 #18

    Ivan Seeking

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    The elements of human testimony, the irreproducibility of observed events, and the lack of any explanation in the face of scientific scrutiny are paralleled strongly. It is a historical measure of the accuracy of human testimony when it is not supported by science.
     
  20. Jul 27, 2004 #19

    FZ+

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    But they have been reproduced. The waves are solitons, and can be easily replicated in the lab with a big tub of water and a large oscillating motor. Just no one happened to draw the connection. And in the end, these sinkings turned out not be the effect of monsters, and (dare I say it?) UFOs, but were perfectly mundane products of an adjusted model.

    It's comparable to flying saucer sightings turning out to be clouds, swamp gas, and venus, after all.
     
  21. Jul 27, 2004 #20

    Ivan Seeking

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    You are missing the point. First, solitons may explain some rogue waves and likely do. This was proposed by the scientist who first spotted these things on satellite images. Next, no comparison is made to claims of monsters; we have been talking about the very existance of these rogue waves. You are trying to a assign source when I was only pointing to the fact that these rogue waves do exist; as was claimed. People saw what they said that they saw in spite of the fact that only now can we explain these observations; so of course only now are we talking about it in a serious manner.

    So, the skeptics were wrong; again.

    Also, you are the only person I have ever heard suggest a relationship between rogue waves and monsters. You are in quite an elite group it seems. :wink:
     
    Last edited: Jul 27, 2004
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