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.

on a map

[Paktu]

Here's [wisc.edu] a pretty good example of what this looks like on a weather map

Air & Water are both fluids...

[Zymergy]

...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]

Re:Surf's up

[Tastecicles]

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:Really nice images!

[LadyLucky]

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:Surf's up

[Silver Sloth]

London -> New York 7.5 hrs
New York -> London 6.5 hrs

Given how much I hate long flights I love coming home.

Re:Really nice images!

[Scynet85]

Youtube has a nice video of these 'gravity waves' you mentioned: http://www.youtube.com/watch?v=yXnkzeCU3bE [youtube.com]

Re:Surface Tension?

[Bentov]

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 it's only really an issue if you are trying to launch a barn or other non aerodynamic object into space.

Same video on Youtube

[Anonymous Coward]

Since the NASA site download seems slow right now:

http://youtube.com/watch?v=aako5siSTgM [youtube.com]

Re:Storms also "breath".

[mikael]

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]

Re:atmospheric waves

[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.