Airplanes Cause Accidental Cloud Seeding 151
An anonymous reader writes "A new study by a team of U.S. researchers found that commercial and private jetliners may be contributing to a form of accidental cloud seeding. When an airplane flies through a cloud, its propellers cause the expansion and cooling of the air behind them which can cause water droplets to spontaneously cool and crystals to form. The aircraft sets off a chain reaction in the cloud that can continue on for hours after the plane has passed by. The researchers also discovered that this phenomenon is more common near the poles, where many of Earth's weather monitoring systems are, and it could be skewing data that research teams are gathering in those areas."
Not new news (Score:5, Informative)
Examples: http://bit.ly/lAxNQO [bit.ly]
How is this news (Score:5, Informative)
I mean seriously, this has been known for decades. There was even a study that looked at the 9-11 shutdown of air-traffic affected climate [cnn.com].
This has been known for a long time.
Spammy Inhabitat link instead of Science Daily. (Score:5, Informative)
"commercial and private jetliners" "When an airplane flies through a cloud, its propellers"
The number of jetliners with "propellers" is mighty fucking few, though not zero.
Linking to the PARENT Science Daily piece
http://www.sciencedaily.com/releases/2011/06/110630142835.htm [sciencedaily.com]
instead of the pointless Inhabitat bullshit summary would have been nice. There is NO excuse for the Inhabitat link other than SPAM.
AC is anonymous because he/she/it wants page hits for Inhabitat.
Now I know not to visit Inhabitat again. Fuck you too and thanks for nothing.
http://www.sciencedaily.com/releases/2011/06/110630142835.htm [sciencedaily.com]
Re:"Propellors"? (Score:4, Informative)
I saw some yesterday, Dash-8s and there a lot of other propeller commercial aircraft out there.
http://en.wikipedia.org/wiki/Bombardier_Dash_8 [wikipedia.org] - turboprop
http://en.wikipedia.org/wiki/Beech_1900 [wikipedia.org] - turboprop
http://en.wikipedia.org/wiki/Cessna_406 [wikipedia.org] - turboprop
We even have one of these flying out of Anchorage
http://en.wikipedia.org/wiki/Lockheed_L-100_Hercules [wikipedia.org] along with
http://en.wikipedia.org/wiki/DC-3 [wikipedia.org]
http://en.wikipedia.org/wiki/DC-6 [wikipedia.org]
http://en.wikipedia.org/wiki/Short_360 [wikipedia.org]
Re:Spammy Inhabitat link instead of Science Daily. (Score:4, Informative)
> The number of jetliners with "propellers" is mighty fucking few, though not zero.
The number of airliners with gas turbine engines that turn propellers is in fact quite large.
The bypass fan of a high-bypass turbofan engine is essentially a propeller as well, although ducted.
So that leaves us with the various 707s, DC-8s, and 727s and their military equivalents flying around out there with straight turbojet engines having no fan-push component, which is not all that many in 2011.
sPh
In any case the results of this study should have been blindingly obvious to anyone living in North America during the no-fly week of 9/11 - 9/18.
Re:arg (Score:5, Informative)
Oh, ferkrissakes, I came here to use up my last two mod points and almost every comment is ignorant, so I'm going to just make one comment and watch a movie and use those two points in the morning.
I know it's not usual for anybody to RTFA and instead just jump to conclusions thinking you know everything without having a clue, so I'm going to clue a few of you guys. This is not about contrails. Of course contrails have been known about forever. I didn't read this particular FA but I saw another FA about this earlier today, and it was damned interesting.
If it was about contrails, most of you guys would still be wrong. Contrails aren't caused by the turbines, they're caused by the air passing the wingtips of the aircraft. If you want to learn more, there's wikipedia for that.
This is about circular holes in clouds, It's about the exact OPPOSITE if contrails. The cause of contrails is well known, the cause of this particular phenomena isn't known. I find it hilarious that you guys think you know more about physics than folks who've been studying physics all their lives.
I'm not a physicist or meteorologist, but at least I know enough to know the limits of my own ignorance, so I READ. Voraciously. The more I read the more I learn, the more I learn the more I understand how ignorant I am. You guys might try reading once in a while. You're ignorant -- we're all ignorant. A physicist doesn't know shit about cosmology, and a cosmologist doesn't know shit about paleontology.
The man who thinks he knows everything cannot learn. Thus endeth the lesson, grasshopper.
Re:arg (Score:5, Informative)
If it was about contrails, most of you guys would still be wrong. Contrails aren't caused by the turbines, they're caused by the air passing the wingtips of the aircraft. If you want to learn more, there's wikipedia for that.
Ironic, considering the tone of your post, but I actually *did* look up (and read) the contrails article on Wikipedia, and you are in fact very wrong. http://en.wikipedia.org/w/index.php?title=Contrail&oldid=436631379 [wikipedia.org]
Contrails (play /kntrelz/; short for "condensation trails") or vapour trails are artificial clouds that are the visible trails of condensed water vapour made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets. If the air is cold enough, this trail will be comprised of tiny ice crystals.[1]
The wingtip vortices which trail from the wingtips and wing flaps of aircraft are sometimes partly visible due to condensation in the cores of the vortices. Each vortex is a mass of spinning air and the air pressure at the centre of the vortex is very low. These wingtip vortices are not the same as contrails.
Re:"Propellors"? (Score:4, Informative)