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Airplanes Unexpectedly Modify Weather
reillymj writes "Commercial airliners have a strange ability to create rain and snow when they fly through certain clouds. Scientists have known for some time that planes can make outlandish 'hole-punch' and 'canal' features in clouds. A new study has found that these odd formations are in fact evidence that planes are seeding clouds and changing local weather patterns as they fly through. In one case, researchers noted that a plane triggered several inches of snowfall directly beneath its flight path."
Was this plane belonged to the Mexican Cocaine Cartels, who thought they were being trailed.
Interesting. So the effect of cloud seeding is just as likely to be caused by the planes flying through the clouds rather than the silver iodide alone?
How long before a conspirationnist comes up with a chemtrail comment?
So, we're surprised when a large metal object that sucks in cold air and spits out water vapor (and CO2) by the ton, affects cloud formation?
This isn't terribly surprising. Clouds are a delicate formation of moisture that hasn't collected into dense enough masses to fall. Aircraft disturb the air, blowing that moisture around. We've known about contrails for an awful long time. I wouldn't be terribly surprised to find that particles in the exhaust give the moisture something to cling to (i.e., cloud seeding).
Those are some nice pictures though.
Serious? Seriousness is well above my pay grade.
They are just giant butterflies, after all.
The data from the near-universal grounding of US airspace the days following the 9/11/01 attacks shows pretty conclusively that air traffic has a non-trivial affect on weather patterns. Or at least that's what's I recall from the time.
Method of processing duck feet
what's the problem {?|.}
It is well known locally on the Canary Islands that this happens. Almost all flights come in on Tuesdays and Saturdays if I remember correctly - they're almost all package deals and charters. By the afternoon on those two days the temperature drops several degrees celsius and you'll see clouds. I even saw a dribble of rain once.
I was a complete skeptic when I was told this as I arrived, but like clockwork on those days I always saw the same thing. The crazy thing is that any other day of the week around the summer you can expect mid-to-high thirties and rarely a cloud in the sky. So maybe not scientific, but anecdotal evidence anyway.
I never get used to these constant resurrections
Sure they weren't just emptying the onboard toilets?
Then there would have been blue clouds and blue snow.
Anyway, Pilots couldn't even if they wanted to.
RIP America
July 4, 1776 - September 11, 2001
I'm not deep into the AGW/anti-AGW arguments (and not trying to start a flame war), but I thought that one of the anti-AGW arguments was that in general humans can't affect climate. This sort of research would seem to suggest that humans can affect climate and hence nullify some of the anti-AGW stance - or are these effects so localized that you can only state that the humans are affecting weather and not climate?
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I wish I could tag this one as duh. Weather is bound to be generated when you pass a hot jet engine through a cold cloud. Not to mention the heat of the fuselage generate from air friction. Although, I was impressed that several inches of snow has the potential to form.
to create a rain/snow storm in a given area certain things have to happen
lets say you need to roll 60 on a d100 to get rain and roll a 4 (on a d6) to get snow IF YOU ROLL RAIN
just dartboarding a few factors you need to have
greater than X% humidity (add 7 to your roll for every 10% above X)
a cold front near by to generate the clouds (and provide for some winds) (add 2 for every 1.5 degree difference)
enough seeds in the clouds to tilt things past the equalibrium
a low enough temp that the water doesn't boil off (penalty of 1 on the d6 roll for every 20 degrees above 0C)
now having a bunch of planes i would bet could 1 add to the "muck" in the air 2 twist the temps a bit 3 do a whole lot more than a butterfly in generating wind
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I find it a little odd that TFA talks about how an aircraft flying through a cloud causes it to "cool", resulting in the supercooled liquid suddenly freezing. There's a very well known phenomenon with supercooled water where it will remain in a liquid form, until it comes into contact with ice crystals. I would think that that was a far more likely cause of the clouds suddenly being filled with ice rather than a jet or turboprop "cooling" an already supercooled cloud.
My 2c
dnuof eruc rof aixelsid
>>The contrail cover from planes reflect more light from the sun.
Also, it's important to state that up until this point, climatologists thought that contrails had a forcing effect helping to cause global warming. And still show it that way, for example: http://en.wikipedia.org/wiki/Radiative_forcing
However, papers like this: http://www.nature.com/nature/journal/v418/n6898/full/418601a.html rather convincingly argued that they have a rather strong forcing in the opposite direction (i.e. that they help to dim sunlight more than they trap heat).
While honest climatologists will admit that some areas in AGW are very well understood, and others are much less understood, dishonest climatologists will pretend that they know everything and how dare you for questioning the global warming groupthink. In fact, how they respond to reasoned criticism is often a clear giveaway as to which camp they fall into.
Anyone who has watched weather fronts as they approach DFW airport can provide anecdotal data showing the reverse effect -- aircraft disperse clouds. Huge storm fronts slam into Fort Worth, the middle dissipates as it approaches and passes over DFW airport, then storm fronts reconnect east to reform a single storm front. How far east depends on the strength of the storm. Or the splitting of the front at DFW airport will cause the storm front to degrade to localized cells. Very few storm fronts survive the impact of DFW airport as a continuous front. YMMV....
Every mans' island needs an ocean; choose your ocean carefully.
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I hope that helps.
Your post is littered with falsehoods. I barely know where to start. Whether you realize it or not, you're concern trolling from ignorance.
We still do not have enough evidence to prove that burning fossil fuels will produce global warming.
Eh? What?`
First off, basic physics predicts that more CO2 and methane (and other greenhouse gasses) in the air will cause the atmosphere, and hence, the ground, to heat up. In a glass jar, CO2 behaves precisely as expected.
The Earth is more complex than a glass jar, it's true, but to argue against global CO2-based warming, you need a plausible physical explanation for where the heat caused by the CO2 went. Unless some obscuring agent prevents sunlight from hitting the CO2, the heat from was undoubtedly generated in the atmosphere nearly exactly as predicted by physics. So where does it go?
In addition to a magic (heretofore invisible) heat-sink, you need a plausible alternative explanation for the geologic record, dating back 100s of thousands of years, showing that, indeed, CO2 and warming are in a feedback-loop, punctuated by various global disasters.
Now before I continue, let me just get this out of the way: there is a difference between someone who believes global warming *can't* be true in the religious sense, and someone who recognizes that climate is a difficult subject for which we just don't have the answers now.
This is a ridiculous cop-out, and is a lousy argument for destroying civilization as we know it.
The fact is, we've had a pretty nice equilibrium here for thousands of years. Throwing off that balance could mean a lot of different possible things, but it definitely means chaos and turmoil.
We don't know everything, but we know some things. We know that the gulf-stream is very important to heating up North America. We know that North America would turn in to a block of ice if it were to shut down. We may not know how to keep it running, but that's not a good reason to toss a bunch of carbon in the air to see what happens.
The best plan is probably to try to maintain the equilibrium somehow. It's worked for a while. I like the coasts where they are, and I don't want to experiment with their shape, thank you very much. If I were in a rowboat with you, I also wouldn't want you to experiment by standing up and rocking it back and forth.
I'll deal with two more of your arguments.
Global temperatures have been on the decline for the last decade, much as they did during the turn of the century 100 years ago.
Incorrect. 1999-2009 were the hottest decade in human history. 2009 was about as hot as the previously hottest year on record, 2005, and possibly hotter, depending on what source you use. This can hardly be described as a decline, and is a typical misconception sponsored by various media outlets.
2010 is trading on Intrade at 67% to be the warmest year on record. You could make a pretty nice sum by betting against it, getting back two times your money at that price level.
Only if you cherry pick 1998-2007 from the data can you claim a "decline", which really isn't a decline, it's a squiggle that bounces back and forth, ending up just below the top.
You may not be a denier, but you sure play one on /.
We can probably agree that CO2 is a greenhouse gas; what we can't explain is why increased generation of CO2 hasn't resulted in a proportionate increase in the atmospheric CO2 levels.
Possibly because you made up that as a requirement. Your argument is irrelevant and spurious. Physics predicts a warming as CO2 rises. CO2 levels are rising dramatically, as we have observed. The temperature is rising dramatically, as we have observed, your weak protestations to the contrary notwithstanding.
Yes, the oceans absorb some. This isn't a question as you intimate, it has been measured. The question of whether increased CO2 in the atmosp
To quote wikipedia:
is inherently invalid.
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