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Zapping Contrails With Microwave Emitters 125

Posted by timothy
from the set-it-for-beverage dept.
An anonymous reader writes "Dissipation of contrails with a powerful microwave beam aligned behind aircraft engines is being touted as a possible solution to help address air transport's effects on the climate. 'The remote heating of condensation nuclei could be achieved by applying electromagnetic radiation, such as microwaves,' says Cranfield University's Frank Noppel. 'Depending on assumptions made, calculation shows that the power required for such a device could be as little as 0.1% of the engine power.'"
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Zapping Contrails With Microwave Emitters

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  • I'm confused (Score:5, Interesting)

    by stoolpigeon (454276) * <bittercode@gmail> on Thursday November 20, 2008 @06:15PM (#25838559) Homepage Journal

    My understanding was that contrails contribute to global dimming and are helping to keep temperatures down. If I read the article correctly, this would not remove any pollution, just remove the clouds and allow temperatures to be even higher. Reading it made me think that the goal has become to have no impact on climate at all - positive or negative. That doesn't seem right, so I think maybe I'm missing something.

    • Re: (Score:3, Funny)

      by Knara (9377)
      No, they're doing us a favor by zapping them so that the government mind-control chemicals will no longer effect us. c.f. "They Live" =D
      • by abigor (540274)

        Rather horribly, I know a girl who believes that to be true - in fact, she thinks "They Live" is a sort of documentary thinly veiled as fiction. Not only is the government dropping stuff from high altitude jets onto its citizens, but it's also under the control of the Illuminati (she uses that word). Everywhere we go, she points out signs that the Illuminati are controlling us.

        Last I heard, she was moving to a rural area to buy land and build a "compound" (again, her term). Even scarier is the fact that she

        • by sumdumass (711423)

          I can see where her beliefs actually some from. After all, the government did spray biological chemicals with specific markers in the from the skys between 1992 and 1999. Of course this was to check for the spread of a chemical or biological attack and the effects on the populations. I believe at one time, they actually use the common cold as the chem.

          This happened across most of the free world to be exact and it started in other areas back in the late 80's as part of a weapon's defense program. It turns ou

          • by abigor (540274)

            Well, she believes the Illuminati are some sort of space aliens...so yeah, more than just somewhat crazy.

            • by sumdumass (711423)

              Yea, I have a cousin like that too. Except he thinks the Illuminati was formed to take over the US in 1776. I ask him how that's possible because that when we started our war with England so that would make us the results of the Illuminati and the secrete government they set out would be them themselves and the government we know today. Then he goes on to claim that the government made the Illuminati and all other secrete societies illegal and they went underground and so on. I don't think logic plays too m

        • FNORD! :-)
        • by DingerX (847589)
          They Live is a documentary thinly veiled as fiction. It's just Frankfurt School Marxism, and nothing more sinister than that.
      • Re: (Score:3, Interesting)

        by negRo_slim (636783)

        No, they're doing us a favor by zapping them so that the government mind-control chemicals will no longer effect us. c.f. "They Live" =D

        I'm glad someone finally had the courage to get the ball rolling on this [wikipedia.org]. Sir, I applaud you for bringing this very real [worldaffairsbrief.com] issue to light. Often times I wonder [luxefaire.com] why the relationship [conspiracyarchive.com] between the pharmaceutical industry [psorsite.com] and secret government [meta-religion.com] organizations [mormonconspiracy.com] isn't more apparent to "normal" [aliendave.com] people.

        • by jeffmeden (135043)

          I'm glad someone finally had the courage to get the ball rolling on this [wikipedia.org]. Sir, I applaud you for bringing this very real [worldaffairsbrief.com] issue to light. Often times I wonder [luxefaire.com] why the relationship [conspiracyarchive.com] between the pharmaceutical industry [psorsite.com] and secret government [meta-religion.com] organizations [mormonconspiracy.com] isn't more apparent to "normal" [aliendave.com] people.

          For once, the slashdot url announcer is useful! There is no way I would have clicked through every link in order to keep up with your joke.

      • by neomunk (913773) on Thursday November 20, 2008 @09:04PM (#25840511)

        Zapping them so that they no longer effect us? Pssh, my source says that the microwaves are needed to ACTIVATE the next generation of chemically generated complacency.

        Then again, the same guy swore Ron Paul was going to win the popular vote...

        • by bky1701 (979071)
          What? You can't really think he didn't! It was rigged, I tell you.
        • Yeah - I know there were a few people on the Ron Paul Forums that were talking about contrails being chemtrails. I think those people were agent provocateurs (importers) or just real bona fide idiots. TRUST ME, those clowns don't represent Ron Paul or the liberty movement.

          • by neomunk (913773)

            Yeah, I understand. I'm supported Kucinich in the primaries and took crap for it for exactly the same reason. I was just being funny in topical way, not trying to slam anyone's political beliefs.

    • by logjon (1411219)
      Your understanding is flawed.
    • Re: (Score:3, Interesting)

      by speroni (1258316)

      Vapour trails or contrails, by affecting the Earth's radiation balance, act as a radiative forcing. Studies have found that vapour trails or contrails trap outgoing longwave radiation emitted by the Earth and atmosphere (positive radiative forcing) at a greater rate than they reflect incoming solar radiation (negative radiative forcing). Therefore, the overall net effect of contrails is positive, i.e. a warming.[2]

      Wiki [wikipedia.org]

      Kinda sounds like BS to me... They are somehow different from normal clouds in that they

      • Re: (Score:3, Interesting)

        by John Hasler (414242)

        > Kinda sounds like BS to me...

        It isn't.

        > They are somehow different from normal clouds in that they trap more heat than they reflect?

        No, they are like normal clouds. Some clouds reflect more heat than they trap, some trap more heat than they reflect. Contrails are like the latter.

        • Re: (Score:3, Funny)

          by speroni (1258316)

          We should microwave _all_ the bad kinds of clouds then.... what could go wrong?

        • Re:I'm confused (Score:5, Informative)

          by ceoyoyo (59147) on Thursday November 20, 2008 @07:06PM (#25839263)

          From the wiki article it sounds suspiciously like contrails have a warming effect when they're produced either a) at night or b) during the winter. From the percentages listed, it appears that the contrails may well have a cooling effect if they're produced during the day and/or not during the winter. That makes the assertion that the net effect is heating a little easier to swallow.

          No, I didn't check out the typically mangled Wikipedia reference. Seriously... citations are great, but you use journal abbreviations and short form references when you're trying to cram them onto one page abstracts, NOT when you're putting them on web pages where space is free.

          • by fbjon (692006)
            Re: citations... you're supposed to be able to read the article, not stop-and-stutter over it.
            • by ceoyoyo (59147)

              I'm not quite sure what you mean. I've never stopped and stuttered because there's a little superscript number. But trying to find "Ponater et al., GRL, 32 (10): L10706 2005" at the very least requires looking up "GRL" in a list of journal abbreviations. If the author bothered to use an official abbreviation, of course. And that's one of the better citations. I've seen a few that give just a name and a city.

              The citation after that one is written properly:

              Stuber, Nicola; Piers Forster, Gaby RÃdel,

              • Re: (Score:3, Informative)

                by fbjon (692006)
                Sorry, now I see. I thought you meant that the citations should be in the article. The abbreviation was probably copypasted from somewhere, though. For the interested, it's Geophysical Research Letters 32 (2005).
      • Re: (Score:3, Funny)

        by ceoyoyo (59147)

        Not to mention a little extra CO2 from the 0.1% extra fuel that needs to be burned to power the microwave. And the extra fuel needed to carry the thing.

    • by SuperBanana (662181) on Thursday November 20, 2008 @07:04PM (#25839233)
      ...not the contrail itself. Jets release huge quantities of "unburned hydrocarbons, particulates, sulfates, nitrogen oxides (NOX), and carbon dioxide" (link [csmonitor.com].) This cute little idea will do shit all to help that; it's just a bit of theatrics to make it look to the eye like there is less pollution.

      Remember how in Sim City an airport would dramatically increase pollution for your city? Yeeeeeah, it isn't far from the truth. Airports aren't transportation hubs; they're giant kerosene burners, which is why the air absolutely stinks for miles around. I seem to recall reading that one 747 during takeoff creates more pollution than a Toyota Prius will in its entire serviceable lifetime. Obviously you can't use microwaves at any kind of intensity during taxi, run-up, or takeoff, as the ass end of the plane is facing near or at the ground.

      Also, it's pretty famous now, but someone studied the weather records around September 11th, 2001 and found there was a remarkable change in the weather across the country and in fact much of the world on the few days that followed where there was very little in the way of air traffic (and another change back to "normal" when air traffic resumed.) Ask most people and they remember it being rather nice out. I remember the weather in lower NY was absolutely spectacular for several days- beautiful blue skies like I'd never seen before in that part of NY.

      • I remember the weather in lower NY was absolutely spectacular for several days- beautiful blue skies like I'd never seen before in that part of NY.

        Just wanted to note that I experienced the same thing, but have a couplre observations:

        Do you recall the weather on 9/10/01 and the morning of 9/11/01? Absolutely gorgeous, nice shore breeze so we had clean air, sunny, and low humidity. I'm not sure if the weather subsequent to 9/11 was part of the same weather pattern or not, or how much impact reduced air t

        • Can't remember who precisely did the research, but I was watching an old Nova documentary yesterday about global dimming, and apparently by measuring the difference between daily highs and lows over the days surrounding 9/11, the days immediately after had a significantly smaller temperature range than the others. This was supposed to be a good indicator there was an effect on the weather, because the range trends usually change gradually. Interesting stuff.
      • by Anonymous Coward

        I seem to recall reading that one 747 during takeoff creates more pollution than a Toyota Prius will in its entire serviceable lifetime.

        Let's not compare apples to oranges.

        A 747 can carry up to 660 passengers in a single-class configuration. That's 132 priuses full of people.

        To drive from NYC to LA is 2,791 miles. Repeating that drive 132 times will put 368,412 miles on your odometer. Although I'm sure the Prius is a very reliable car, it's unreasonable to expect any vehicle to last that long without a major overhaul.

        • by Nick Ives (317)

          My parents ran a taxi for just over 300,000 miles. That was a pretty reliable car (Peugeot 405 diesel, can't remember the year but would have been early to mid 90s) but 250,000 miles wasn't unusual for them. I don't think it had many major overhauls in its lifetime, when you're running a taxi it's best to buy the most reliable car you can find new and then run it down to scrap. You don't even bother with dealer servicing, you get a trusted mechanic who can do things cheap.

          These are UK miles though, don't kn

    • It makes sense to me - mornings are always warmer if the night was overcast, at least where I live.
    • Ya, I'm still working on how warming the exhaust of a jet is going to "Help" global warming.?

    • by Culture20 (968837)
      Who cares about temperature? I just want to see clean blue skies again. There was only one week in my life when I didn't see jet contrails in the sky, and while I was able to appreciate the beauty, knowing why the beauty existed made me feel a little guilty.
    • It's not that complex. You just need to remember the implications of earlier experiments [youtube.com].

  • If this technology gets put into use, conspiracy theorists will start asking why they are covering up the contrail activity. Unless the "chemtrails" are not susceptible to microwave heating dispersement, then they will have something else to point at. I initially thought this was an article about a device to combat chemtrails being developed by said conspiracy theorists.

    It will be interesting to see if a trend develops of pre-cooked birds falling from the sky behind jetliners outfitted with this techno
    • It will be interesting to see if a trend develops of pre-cooked birds falling from the sky behind jetliners outfitted with this technology.

      Roasted fowl falling from the heavens? It's like the Bible, only I don't have to be wandering in the desert!

      Hang on...they'll be using microwaves?

      Never mind. I can get that without leaving the basement.

    • by Altus (1034)

      No no no... you've got it all wrong. Chemtrails are susceptible to microwave heating disbursement, but that's a GOOD thing... this way the mind control chemicals they are spreading will disperse faster and they wont need to use as much of that expensive stuff to keep the populations docile.

      They cant just implement it though because people would get nervous if the chemtrais just suddenly disappeared so they need a good public justification for the change.

    • by RichiH (749257)
      Said birds would also be plucked and chopped, already.
  • Although this seems interesting I think the airline industry has other more pressing worries. The current financial market has pretty much guaranteed that they can do nothing "green."
    • The current financial market has pretty much guaranteed that they can do nothing "green."

      On the contrary, there are many 'green' innovations that are actually cost saving innovations. Look at the Boeing 787 (if it ever gets off the ground) it uses much less alluminum and has 20% higher fuel efficiency. Modern innovation is both green and economical.

      • by Afforess (1310263)

        On the contrary, there are many 'green' innovations that are actually cost saving innovations. Look at the Boeing 787 (if it ever gets off the ground) it uses much less alluminum and has 20% higher fuel efficiency. Modern innovation is both green and economical.

        The innovations are cost saving over the Long Term, but not in the short run. To the airlines, this is all that matters. Your example has nothing to do with "green" technology, instead it is merely cost cutting. An example of "green" technology would be cleaner engines. You can't lob off a few pounds of metal and tout it as "green."

        • So not having to mine and refine a few extra tons of alluminium doesn't help the environment? Reducing fuel burned by 20% doesn't reduce greenhouse gases and particulates? I'm confused by your definition of green technology, unless you mean 'technology that's only purpose is to be more environmentally friendly'. If that is what you mean, then by your definition there isn't a single major corporation that has significantly invested in green technology.

          • by cdrguru (88047)

            Wouldn't it be more "green" to not build the airliner in the first place?

            Wouldn't it use less fuel if it had never been built?

            Wouldn't the climate be helped far more if airplanes were reserved for government and military use only?

    • Re: (Score:3, Informative)

      by Red Flayer (890720)
      What are you smoking?

      Define "green". If you're using it in the common manner, it means one or more of the following:

      Reduced carbon footprint
      Reduced toxin output
      Reduction of resources required to produce
      Reduction of resources required for operation

      And note that this is per unit of work, whether that is passenger-mile or some other measure of work.

      Note that while substitution of resource requirements can go either way with cost, reduction of resources for operation will by definition reduce cost.

      Maybe y
  • Logic abounds! (Score:4, Informative)

    by MaxwellEdison (1368785) on Thursday November 20, 2008 @06:35PM (#25838871)
    Reduce the atmospheric warming effect of contrails by microwaving and thereby heating the atmosphere...

    Dare I say...BRILLIANT!


    Actually, I wonder what effect this would have on those pesky naturally occuring clouds...
    • by Incy (635621)
      I thought contrails *lowered* the temp? Didn't we see a lowering of the temps in the US when plans stopped flying after 9/11? They are white clouds that reflect heat back out.
      • There's debate about that. And, like anything related to climate change, if there is debate ongoing we must begin implementing the idea immediately.
        • by Shark (78448)

          This [telegraph.co.uk] is how you deal with pesky debates that get in the way of a political agenda.

    • Reduce the atmospheric warming effect of contrails by microwaving and thereby heating the atmosphere...

      Actually they are cooling: they reflect sunlight back into space and produce global dimming which counteracts the greenhouse effect. There was a study done comparing day-night temperature differences over the period around the 11/9 attacks when air travel was grounded over the US that suggested air travel had a significant contribution to global dimming.

      Of course it is still a stupid idea: reduce global dimming which offsets the greenhouse effect by burning more fuel which makes the greenhouse effect wo

      • by gad_zuki! (70830)

        >around the 11/9 attacks

        Oh yes, the old 11/9 attacks. Who would have forgotten the rabid robot uprising on November 9th. Never forget! I still have a scar from a laser burn!

        I dont care if youre british or what, its called "9/11." Thanks.

        • Sorry, my post was in English. My apologies for not including an Amercan translation for you, I didn't realize it would make you angry but you at least seemed to have figured it out yourself, well done!
    • Reduce the atmospheric warming effect of contrails by microwaving and thereby heating the atmosphere...

      Dare I say...BRILLIANT!

      Without knowing the math, we can't tell if it's brilliant or not. It's quite possible that the heat produced by the microwaves is less than [(insulating effect of the contrails) - (albedo effect of the contrails)].

      And what's more, what if the energy used to 'zap' the contrails was produced via solar power... then it puts us in better shape heatwise, since instead of the solar e

    • What about my damned WiFi signal! Are they using regular microwave frequencies or, you know, 2.4GHz to cut down on license costs.

      • by borizz (1023175)
        Probably 2,4GHz, because it cooks water really nicely. That's also why kitchen microwave ovens use it.
  • by frovingslosh (582462) on Thursday November 20, 2008 @06:39PM (#25838943)
    a possible solution to help address air transport's effects on the climate........ so the "a possible solution" to those little white trails behind jets that usually dissipate quite quickly is to shoot a powerful microwave beam in the sky. What could possibly go wrong?
    • > ...shoot a powerful microwave beam in the sky. What could possibly go wrong?

      After all, it's not as if anyone has ever "shot a powerful microwave beam in the sky" before...

      • Well, it's not as if coning trails are all that new. They hardly bothered most of the alarmists for years (except of course the ones with secret chemicals in them that the conspiracy theorists tried to warn us about). It comes as a shock to me that any eco-kook that would worry about these trails would not be more worried about the microwave scheme.
  • I thought we weren't meant to put metal in the microwave.
    If the targeting was off just a bit wouldn't this be a little bit bad for the occupants?

    However, having pre-cooked birds falling from the sky would help with feeding the family.

  • Passenger: My $8 cilantro-turkey-roll-lettuce wrap is cold!

    Flight attendant: Sir, we heated it in the microwave, but by the time we reeled it back in, it had cooled down to 30-below. Would you rather have the $9 Pepperidge Farm cookie?

  • "Microwaving Contrails" would be a good name for a rock band...

  • 0.1% is huge! (Score:5, Insightful)

    by camperdave (969942) on Thursday November 20, 2008 @06:57PM (#25839139) Journal
    calculation shows that the power required for such a device could be as little as 0.1% of the engine power.

    A 747 uses four RB211 engines (or the Pratt & Witney equivalent) each of which puts out 30 megawatts of power. So this microwave contrail zapper is going to be using 120 kilowatts of power? That's 60-80 kitchen microwaves running simultaneously. That's more power than many radio stations use to transmit. I can't help thinking this will cause more problems than it solves. How is it going to affect radar, TV, cell phones, etc? How is it going to affect other planes on the same flight path? How is it going to affect the moisture already in the air? What's going to happen when one of these aircraft come in for a landing and forgets to turn off their contrail zapper?

    It's probably money a lot better spent trying to build cleaner burning engines in the first place.
    • > It's probably money a lot better spent trying to build cleaner burning engines in the
      > first place.

      Contrails have nothing to do with how clean-burning the engines are.

    • And what happens if they fly past a piece of aluminum foil?

    • by torkus (1133985)

      And they're still worried about my cell phone that transmits at what, a few 100mW? Even if you went two orders of magnitude higher - 10W it's effectively zero compared to what they're suggesting.

      So yeah, fuck you FAA my cell phone isn't going to crash a plane.

      To be slightly on topic - there are people who think contrails are tin-foil-hat stuff. When i read this it seemed like a big waste just to shut those people up. Still, I think this IS a big waste regardless.

  • by vrmlguy (120854) <samwyse.gmail@com> on Thursday November 20, 2008 @07:02PM (#25839203) Homepage Journal

    Jet contrails apparently serve to cool the Earth during the day, as they reflect solar radiation, while at night they serve to warm the Earth, by trapping heat. So for maximum effect, you'd want to only dissipate the contrails created during nighttime flights. This would include not just "red-eye" flights, but air cargo operations like FexEx. Measurements taken during the grounding of all commercial flights following 9/11 indicate that there was a two degree increase in the range of day/night temperatures, so elimination of just the nighttime contrails could lower temperatures by a degree or so.

    http://archives.cnn.com/2002/TECH/science/08/07/contrails.climate/index.html [cnn.com]

    • I cannot vilify Gore anymore when he flies to his latest Global Warming conference because by using his private jet he is helping save the planet?

      arrggghhh!!!

    • by tsstahl (812393)
      Pfft, just mandate that every day flight have a corresponding night flight to cancel each other out!

      -Brought to you by the Committee For The Catastrophically Simple.
  • My first expectation was something for bomber jets to make them less visible. I'd be surprised if it doesnt get ported over.

    • I imagine in this day and age that having a giant fuckoff microwave transmitter would make the bomber more visible, not less.

  • And be done with it, Spiro Agnew's headless corpse agrees with this plan.

    Grrrrrrrrrrrrr

  • Aren't contrails supposed to dissipate naturally in the first place? If you look videos of contrails during WWII, they would completely disappear within a minute or two because they are condensation (water) trails. However, some of the planes nowadays leave trails that last hours, sometimes a good part of the day. On top of this, they seem to be able to start and stop these trails on command, lots of pictures and looking up in the sky will show you this. So they want to dissipate these chemtrails now?
    • by Vihai (668734)

      Aren't contrails supposed to dissipate naturally in the first place?

      No, not always.

  • Jet exhaust is already quite hot, thank you very much. Tell me how adding heat 0.1% to the 70% present in the exhaust will prevent cooling, condensation and crystalization of ice.

    Even with lonbg-range microwaves, it'll just recondense since it lost the engine turbulence.

  • I'm only a second year in Aerospace, so I could have this wrong, but: Why implement a device that has significant mass, and requires a "large" amount of energy? The whole point is to reduce emissions, not create them. As I understand it, condensation trails are caused by low pressure areas formed by the wing tips/ends. Is there nothing that could interrupt the formation of low pressure pockets at the rear of the plane? I am aware that pockets of air can help aerodynamics of the jet. (Same principle behind
    • by nedlohs (1335013)

      No, those exist too, but they aren't what is being referred to.

      Contrails are due to the simple fact that burning fuel in an engine produces water vapor. Hot air with a high water vapor content is exhausted from the engine into cold air. It cools. The water vapor is now over saturation point, and condenses into water or ice.

  • It would seem the obvious reason for implementing something with such dubious prospects is to firmly eliminate one of the nasty conspiracy theories/rumors that circles around the drain of the Internet. Chemtrails.

    These are supposed to be something that results from introducing various chemicals to either the jet fuel or into the engines themselves to make for a more docile population. Or to stir things up and create race riots which can then be brutally put down. Or some other result which often the peop

    • The problem with nutjob conspiracy theories like "Chemtrails" is that no matter what you do, they'll just revise the theory. If we create a system for getting rid of contrails, they'll just say that the government is now trying to "hide" the chemtrails by making them invisible, but they're still there!
  • TFA quotes a 1999 article regarding effects of contrail cirrus on climate. That was, of course, theoretical. Due to the few days of no planes above the US following 9/11, we have clear climatological data regarding contrails. Contrail cirrus serves to reflect daytime sunlight back upwards, and night time terrestrial heat radiation back down, the net effect being to reduce the variance in temperature changes over time.

    There is no reason to waste aircraft fuel running microwave generators to ameliorate an eff

  • Perhaps the military see it as a possible solution to reduce contrails on fighter jets?

    Stealth aircraft aren't any good if they leave a visible contrail behind ;) (Actually I'm not sure if/how they've dealt with that on current stealth aircraft?)

       

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