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Earth Transportation Technology

Zapping Contrails With Microwave Emitters 125

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:I'm confused (Score:3, Interesting)

    by speroni ( 1258316 ) on Thursday November 20, 2008 @06:27PM (#25838745) Homepage

    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 trap more heat than they reflect?

    Is that because of the condensation or the actual exhaust carbon particles? Maybe getting rid of the condensation will decrease the reflectivity while leaving the greenhouse gasses there.

    And an extra little microwave energy on top of that..?

  • Re:I'm confused (Score:3, Interesting)

    by John Hasler ( 414242 ) on Thursday November 20, 2008 @06:35PM (#25838881) Homepage

    > 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.

  • 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.

  • Re:I'm confused (Score:3, Interesting)

    by negRo_slim ( 636783 ) <mils_orgen@hotmail.com> on Thursday November 20, 2008 @07:17PM (#25839427) Homepage

    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.

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