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Giant Atmospheric Waves Filmed Over Iowa

Posted by CowboyNeal on Fri Oct 19, 2007 02:27 AM
from the surfing-the-skies dept.
NASA Space Science
NJChopperMan writes "For all those of you that thought waves only existed in the ocean, Photos and video of undular bore waves were caught in Iowa last week." The story also touches on the role of undular bores in severe weather, but it's definitely second fiddle to the video of the waves.
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Submission: Giant Atmospheric Waves Over Iowa by NJChopperMan (1175851)
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  • global warming (Score:5, Funny)

    by timmarhy (659436) on Friday October 19 2007, @02:30AM (#21037889)
    i don't know how, but somehow, this is global warmings fault.
  • Bore waves . . . in Iowa? *yawn* That sounds about right.
  • I thought undular bores are those guys at parties who tell loud political jokes then try to sell you insurance or something.
    • No, they're the people who hear a word like 'bore' and have a knee jerk reaction to make a really lame joke that's a poor variation of a joke you've heard a thousand times before and is normally just the sort of thing someone would say when they have absolutely definitely run out of things to say at a party and they're trying really desperately hard to say something, anything, so as not to look completely and utterly lame.

  • on a map (Score:5, Informative)

    by Paktu (1103861) on Friday October 19 2007, @02:37AM (#21037931)
    Here's [wisc.edu] a pretty good example of what this looks like on a weather map

    • Storms also "breath". (Score:5, Interesting)

      by TapeCutter (624760) on Friday October 19 2007, @05:04AM (#21038631) Journal
      I've been a casual cloud/storm nerd for decades and if you watch the sky long enough you can't help but notice "waves" and "drainpipes" at a more localized scale (particularly when a strong cold front is approaching).

      I currently live a 100M or so from the beach in Melbourne Australia. Small intense storms come in over the bay heading directly toward the beach so you get the front "ledge" of the storm cloud coming over while behind you is clear and the drama is still out in the bay. If you stay still and face toward one of these storms roughly when the cloud/sky boundry is directly over the beach you will feel the wind do a 180deg flip as if the storm is enhaling warm air and exhaling cold with a slight pause in between. It is more pronounced with slow moving storms and can last for 15 minutes or so with a regular inhale/exhale cycle of about a minute. The first exhale of an intense summer storm can feel like someone opened a fridge door if you have been sitting with your back turned and not seen it approaching.

      If rain/hail is heavy enough in the center of the storm you might also see prominent ridges running up the underside of the ledge similar to those in TFA but curved to fit the squashed drainpipe shape of the storm. When the rain/hail gets closer the wind will turn steady and cold (time to go inside).

      Disclaimer: Don't try observing it standing on the beach, and escpecially not with an umbrella!

      • Re:Storms also "breath". (Score:4, Informative)

        by mikael (484) on Friday October 19 2007, @08:15AM (#21040153)
        If you stay still and face toward one of these storms roughly when the cloud/sky boundry is directly over the beach you will feel the wind do a 180deg flip as if the storm is enhaling warm air and exhaling cold with a slight pause in between.

        From some of the research on such phenomena (cloud dynamics), a small thunderstorm consists of a number of cells in which air is either moving upwards or downwards. This explains this visually [aol.com]

  • Woohoo, let's go gliding! (Score:3, Interesting)

    by 6Yankee (597075) on Friday October 19 2007, @02:43AM (#21037961)
    TFA was pretty light on detail, but these look like a completely different animal from the (warning: gratuitous Wikipedia link) mountain waves [wikipedia.org] so beloved of glider pilots. Wonder if they're soarable?

  • Sky == CRT? (Score:3, Funny)

    by jfim (1167051) on Friday October 19 2007, @02:45AM (#21037983)
    Wow, now I know that the sky refreshes like a CRT now! :)

  • Really nice images! (Score:5, Interesting)

    by muecksteiner (102093) on Friday October 19 2007, @02:50AM (#21038009)
    Atmosperic wave phenomena have been known for ages, and are hardly inconspicious in those places where they regularly form.

    The main "customers" for them are probably glider pilots; as far as I remember, all recent altitude records for soaring have been made using waves formed in mountain regions (14+km), and the current distance record by Klaus Ohlmann (insane 3000+km in one day) was also flown in the waves over the Andes. Thermal updrafts are toys by comparison.

    The one thing that you have to hand to the NASA guys is that they indeed caught some very fine specimens there, and in an unusual place, too. Normally, waves are induced by the flow of wind over a given, usually hilly, terrain. Gravity waves from thunderstorm activity are certainly a lot more esoteric, and what they are saying about them being catalysts for storms sounds really intriguing.

    A.

    • Re: (Score:3, Informative)

      by LadyLucky (546115)
      That's right. The other extraordinary thing you can do in a wave in a glider is get altitude. Like 20, 30 thousand feet of altitude.

    • Re: (Score:2, Informative)

      by Scynet85 (933220)
      Youtube has a nice video of these 'gravity waves' you mentioned: http://www.youtube.com/watch?v=yXnkzeCU3bE [youtube.com]
    • Most famous one is the "Morning Glory" (http://en.wikipedia.org/wiki/Morning_glory_cloud) in Australia.
    • The clouds in TFA are at a much lower altitude, and caused by the "sloshing" of a static inversion layer, and they move forward like ripples in a pond.

      Wave clouds near mountains are caused by the venturi effect as the jet stream passes over the terrain, and they tend to be static - you can watch them form up on the leading edge of the wave and dissipate at the trailing edge.
  • I wonder if aeroplanes could surf these waves and thereby save fuel?

    • Re:Surf's up (Score:4, Informative)

      by Tastecicles (1153671) on Friday October 19 2007, @03:16AM (#21038131)
      They already ride the jetstream and save fuel/time on Transatlantic crossings. I forget which direction, but it's around half an hour saving on flight time. That's a /lot/ of fuel.

      • Re:Surf's up (Score:4, Informative)

        by Silver Sloth (770927) on Friday October 19 2007, @04:03AM (#21038355)
        London -> New York 7.5 hrs
        New York -> London 6.5 hrs

        Given how much I hate long flights I love coming home.
        • This is what I've always heard, but some years ago I experienced just the opposite. I was on a flight from Philly to Barcelona which took about 11 hours, but the return flight from Paris to Dallas was closer to 9 hours. I never did find an explanation.
    • No. The waves move far too slowly to be useful in this regard, and given that they're immense gravity-waves some 5 miles apart, the plane would probably feel like a paper-boat caught in the wake of a super-tanker.

  • Air & Water are both fluids... (Score:5, Informative)

    by Zymergy (803632) * on Friday October 19 2007, @02:58AM (#21038043)
    ...and thus they will both have fluid dynamic behaviors when vibrating (waves) at the interface of another fluid.
    Wave action happens at the disturbance interface (involving the propagation of and/or transfer of energy) between fluids of different densities.
    The Air/Water fluid interface where one observes common "waves" are observed as water waves because the air is transparent (but it too has waves).
    The difference here, is that we have two air masses of different temperatures and humidities (thus having differing densities) interfacing as fluids AND one of them happens to be an air mass that contains visible moisture in the form of clouds.
    It is likely that this type of air/air fluid "wave action" happens frequently at the interface between differing atmospheric air masses (AKA fronts), but in this example the clouds made it easily visible.
    Nice Image too: http://science.nasa.gov/headlines/y2007/images/undularbore/redgreen_big.gif [nasa.gov]
    http://en.wikipedia.org/wiki/Wave [wikipedia.org]
      • Yes, thats why it's so hard to get rockets into space. A common misconception is that gravity is the limiting factor but in fact it's getting enough speed in a sufficiently sharply pointed rocket to break the airs surface tension which is the major challenge.

        • Re: (Score:3, Informative)

          by Bentov (993323)
          I was going to just what you wrote was a complete piece of crap, but I did search before I rashly typed that:

          http://www.physlink.com/Education/AskExperts/ae158.cfm [physlink.com]

          *Snipet*
          The value evaluates to be approximately:

          11100 m/s
          40200 km/h
          25000 mi/h

          So, an object which has this velocity at the surface of the earth, will totally escape the earth's gravitational field (ignoring the losses due to the atmosphere.) It is all there is to it.
          */Snipet*(Bold is mine)

          So while I guess you are theoretically correct, I'm guessing

        • Re: (Score:2, Insightful)

          by Anonymous Coward
          This is the first I've heard of that. And it seems to be false. The main issue with getting rockets away from Earth is Earths gravity.
          You are modded as insightful, but you give no reference link or any other source of your information.
          I don't blame you, I blame the moderators.
        • Congrats on getting this moded as insightful! Sharply pointed rocket indeed.

  • I flew my hang glider on one. (Score:5, Interesting)

    by scorpio_boy (694099) <rolf&mactherapy,com> on Friday October 19 2007, @03:18AM (#21038151) Homepage
    Seriously, go see the photos and video on my blog if you don't believe me at http://rolf.id.au/ [rolf.id.au] We call the resulting visual cloud a morning glory in Australia....
  • I saw the term "bore waves", and suddenly I had a vision of a story about a George Bush press conference...

  • Cute (Score:4, Funny)

    by tygerstripes (832644) on Friday October 19 2007, @04:19AM (#21038415)
    The little yacht dithering about in the water under the impact of these waves is, somehow, very endearing. I keep wanting to give it a saucer of milk.
  • That film was obviously photoshopped! I mean, come ON! [/today's xkcd]

  • Same video on Youtube (Score:2, Informative)

    by Anonymous Coward
    Since the NASA site download seems slow right now:

    http://youtube.com/watch?v=aako5siSTgM [youtube.com]
  • You can see these waves clearly in deserts and then a few minutes later you wish you hadn't.
  • (Think 1980s Flash Gordon)

  • Damn Government! (Score:3, Funny)

    by DrBuzzo (913503) on Friday October 19 2007, @09:50AM (#21041677) Homepage
    This is just more evidence of the need for aluminum foil hats. That damn government with their satellites and chemtrails with the roswell, ufo, grassy knoll, glomar explorer, watergate it's all run by the damn illuminati who are with the freemasons in the center of the hallow, convex flat geocentric earth.
  • Things like undular bore waves are part of the reason why severe weather on a small scale will continue to be difficult (if not impossible) to predict for the foreseeable future. We have a better than ever handle on what's happening at the time, which is enough to give people 15-20 minutes warning ahead of time for severe weather and tornadoes (and has undoubtedly saved thousands of lives since the mid 1940s, when tornado warnings started to be issued).

    But it is still well beyond any computer model in exist
  • Great article. I saw one earlier this summer and it was the coolest thing I think I've seen in the sky. It's akin to something from ID4 (that crappy movie back in '96 with will Smith and aliens) and it's really imposing. Very cool stuff.
  • When I was a kid, one of these passed over our neighborhood. I remember how fast it was moving and how its shape was just to "uniform" to look like it belonged in nature. It was both fascinating and frightning at the same time. I recall it was darker than the one in the video shown in the parent article and had lightning coming out of it as well.

    Real freaky looking, and it unnerved the grown-ups as well as the kids.
  • I saw something that looks similar (but I suspect is a different, though equally cool phenomenon) last December in Cupertino, CA driving west on I-280 (facing the Santa Cruz mountains).

    It looked like the clouds were emerging from the mountains as fine jets that got wider as they got further into Silicon Valley. Anyone know what this is?

    (At the time I thought perhaps they were clouds of flying monkeys from Microsoft's Mac Business Unit -- which is in those mountain

    • Re: (Score:2, Interesting)

      by tygerstripes (832644)
      More interesting are the waves set up by the harmonics of the Atlantic Ocean. There's a particular length (I forget exactly, but it's something close to 100 metres) that nautical engineers will never, ever build their ships to be, because they would get torn apart in the middle of the Atlantic by the simple harmonic motion of these waves.

      • Re: (Score:2, Informative)

        by Anonymous Coward
        Some told you that in a bar, and you should not have believed them. Spectral fatigue analysis is a bit more complex than that. Just trying to simulate the random seaway is difficult, search "pierson and moskowitz" for a good start. People get there PhDs just trying to develop ways to get design loads from wave spectrum. Generally these spectrum focus on the North Atlantic wave climate as it is the worst case environment that most boats would ever operate in.
      • K-Lite Mega Codec Pack. Can play Quicktime directly in WMP or MPC and includes RealAlternative. Never be annoyed by QT or RA players again!
      • Realplayer, maybe, because it uses Microsoft's HTML control like Windows Media Player does. Makes them really nice portable trojan-horse front ends on Windows.

        Quicktime doesn't support that security "feature".

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