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Giant Atmospheric Waves Filmed Over Iowa
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.
i don't know how, but somehow, this is global warmings fault.
If you mod me down, I will become more powerful than you can imagine....
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.
Here's a pretty good example of what this looks like on a weather map
TFA was pretty light on detail, but these look like a completely different animal from the (warning: gratuitous Wikipedia link) mountain waves so beloved of glider pilots. Wonder if they're soarable?
Everything we call real is made of things that cannot be regarded as real. There are some things so serious you have to laugh at them.
Wow, now I know that the sky refreshes like a CRT now! :)
Jean-Francois Im's blog
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.
I wonder if aeroplanes could surf these waves and thereby save fuel?
threadeds blog
...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
http://en.wikipedia.org/wiki/Wave
FYI, atmospheric waves are very common and have very similar structure. In fact, the study of both atmospheric and ocean waves is called Geophysical Fluid Dynamics. It is a fascinating field - my favorites are atmospheric waves in which the wavelength is such that two or three waves encircle the entire Earth.
Seriously, go see the photos and video on my blog if you don't believe me at http://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...
I want a new quote. One that won't spill. One that don't cost too much. Or come in a pill.
No, the obvious question is "How can this benefit ME!" ;)
I...I'm attacking the darkness!
So, does that mean that air has surface tension, like water does?
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.
Meta will eat itself
Nice to see this presented as a Quicktime movie. What other format could this be in where I can grab the play marker and drag it back-n-forth to scrub through the movie?
If I didn't have absolutely NOTHING to do, I wouldn't be here.
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!
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
That film was obviously photoshopped! I mean, come ON! [/today's xkcd]
GAAH! MY PRINTER IS ON FIRE!!! PUT IT OUT! PUT IT OUT!
All of the presidential candidates who have been frequenting the area. I hear everything undulates after having that much asshole that close all at once!!!!
"My immediate reaction is "WTF? What kind of moron doesn't make things 64-bit safe to begin with?" Linus
Since the NASA site download seems slow right now:
http://youtube.com/watch?v=aako5siSTgM
You can see these waves clearly in deserts and then a few minutes later you wish you hadn't.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
(Think 1980s Flash Gordon)
Comment removed based on user account deletion
http://www.youtube.com/watch?v=yXnkzeCU3bE&NR=1
damaged by dogma
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).
:-D
But it is still well beyond any computer model in existence to predict specific features more than an hour in advance (the best that can be done is to issue broad-scale "there is a significant chance something will happen somewhere in this region" alerts). Which is why it will be ever more interesting to see how the National Weather Service integrates tomorrow's technology into their forecasts.
-Rob
Biblical fiscal responsibility
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.
Oh good job, people, you BROKE NASA!
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.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
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.
A goal is a dream with a deadline
http://flickr.com/search/?w=33752399%40N00&q=clouds+storm&m=text I thought they were pretty cool when I saw this as well. Had to race like hell to get my camera and get out in front of the storm far enough to get some shots.
Here is a link to the raw movie file:
http://mesonet.agron.iastate.edu/cases/071002/bore/saylorville_timelapse.mov
and the original youtube video:
http://www.youtube.com/watch?v=DMqhtQyYQzY
This bore was also captured from two other cameras:
Tama, Iowa: http://www.youtube.com/watch?v=D46eNa5sjok
Indianola, Iowa: http://www.youtube.com/watch?v=8AgVYb4hGBU
http://www.youtube.com/watch?v=iu5QCMGNqZA
http://kered.org
- Photo 1
- Photo 2
- Photo 3
- Photo 4
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 mountains -- descending upon Apple's main campus -- which is about a mile behind the vantage point of those pictures)
There is a much better video of atmospheric waves here.
I accidentally read that headline as "Giant Atmospheric Whales Filmed Over Iowa." I immediately panicked and ran off and grabbed a towel and a copy of "The Hitchhiker's Guide to the Galaxy"...
There was this other undulating cloud video from Iowa from a few months ago... It's at 60x normal speed or thereabouts, so I'm not sure the people standing there would notice. Nevermind that the video is titled like a tabloid... It's still impressive.
http://www.youtube.com/watch?v=yXnkzeCU3bE