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Earth without the interaction between ground and atmosphere?

  1. Jul 16, 2003 #1

    wolram

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    i know that other planets in our solar system have lightning storms
    and as far as i know its natures way of keeping the electric feild
    between ground and atmosphere in balance, but what would happen if this system had a "glitch" and an imbalance occured, could the
    atmosphere discharge into space? if so what would happen on earth without the interaction between ground and atmosphere?
     
    Last edited by a moderator: Feb 5, 2013
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  3. Jul 16, 2003 #2

    Monique

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    Astronauts HAVE reported lightning shooting UP from the clouds, usually they have a color. I am not sure if they actually determined what causes these sparks, I saw a video on TV a few years ago and it looks pretty cool.
     
  4. Jul 16, 2003 #3

    wolram

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  5. Jul 16, 2003 #4
    Re: lightning


    Actually thunderstorms act like large Van de Graff generators and charge the upper atmosphere. The ionosphere is one plate of a very large capacitor, the other plate being Earth ground. The capacitor discharges through a very small current, a few microamperes per meter squared, that can be measured with a sensitive instrument called an electrometer.
     
  6. Jul 17, 2003 #5

    Ivan Seeking

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    It is [or at least was] thought than an approximately constant rain of positive charge falls to earth on dust particles, raindrops, ice crystals and the like. This acts to establish the initial separation of charge that makes possible the thunderstorm. The current from this averages as about one microampere per sq. meter.

    Edit: It would seem possible that as the earth becomes more positive, this process may be affected.
     
    Last edited: Jul 17, 2003
  7. Jul 18, 2003 #6
    We have a conflict of theories here, you're saying the charged particles in the atmosphere charge up the ionosphere and that's what produces thunderstorms, from what I learned the storms do the charging and the particles help to discharge the atmosphere. Much of what I learned was in the Feynman Lectures.

    Does the total charge increase or decrease when the number of storms is fewer? How does the force on a charged particle, dust mote, etc., from gravity compare with the force from the electic field of the Earth? How does the total amount of dust falling compare with the total amount of rain in thunderstorms? Answering these questions would sort out the correct theory.
     
  8. Jul 18, 2003 #7

    Ivan Seeking

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    Darn. You caught me going out the door but I can never resist answering these things.



    See the Feynman Lectures on Physics. 1977 version in my case.
    Vol II, Chap 9.

    I have read papers about this that are more recent. The idea is that this constant positive rain creates a surface potential that is typically positive wrt the cloud. Of course the cloud has its own dynamics and another positive charge towards the top, but I think this explanation still stands as the consensus for the charging system; as opposed to thunderstorms that are then the discharging system. If we calculate the total ionic flux over the surface of the earth, we find that this agrees with the total average flow of current going back to the earth if summed over all thunderstorms. The ionic flux can be measured. At least this is what I understand as the state of the theory.
     
  9. Jul 18, 2003 #8
    I can see "potential" (Sorry about that!) problems with both versions. If the dust and rain droplets carry the positive charge to ground, what carries the negative charges to the ionosphere? The rain and dust particles don't get up that far. And if the Ionosphere has a negative charge, it will repel any negatively charged ions. There's no problem with accounting for the net charge and current involved. The real problem is that it takes energy to charge a capacitor, and what is the flow of energy in the system? That is what has to be accounted for to be able to say why the Earth has an electric field.

    It may well be that both work in kahoots to do the job and both have to be included. And the thunderstorm may act both as a charger and a discharger, because there is lightning of both polarities and it goes all over the place.
     
  10. Jul 19, 2003 #9

    Ivan Seeking

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    I would guess that the sun starts the process and gravity finishes the job. I would guess the source for the charges are chemical reactions - such as in the formation of O3 from 2 O2s [edit: and a photon of course] - and collisions between different particles and molecules due to wind currents. In this way the sun might power the process. Then gravity carries the charges to earth on relatively heavy particles. Although I am guessing a bit, this would seem to be consistent with other things that I have read. I will do some looking and see if my SWAGs [Scientific Wild Ass Guesses] can hold water; or if they are all wet.

    I think it is quite likely that many processes are responsible. After all we are talking about an entire planet.
     
    Last edited: Jul 19, 2003
  11. Jul 19, 2003 #10

    Ivan Seeking

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    Well I'm trying to get this straight. It seems that the ionosphere is about 70-80 Km and up [CRC]. By the following link it seems that the ozone layer is limited to about half of that height.

    http://www.epa.gov/ozone/science/sc_fact.html

    HMMM! Wait a minute...are you leading me down the garden path you wascal? Why are we talking about the ionosphere? Clouds don't go up that high either.

    Sudden revelation: sprites and spires do. Now that's interesting... No one knows much about these things yet.

    Revelation #2: And it occurs to me. We get Schumann Resonance in the ionosphere as a result of lightning on the planet. Perhaps spires and sprites are the source of Schumann Resonance. It dawned on me: How does lighting activity communicate to the ionosphere in order to establish the resonance. I had never realized the height of this boundary. Of course I guess this could be a sympathetic process..


    One more thought: What about all of the material raining down from space? i.e .meteor dust, water, alien viruses designed to eradicate the human race?
     
    Last edited: Jul 19, 2003
  12. Jul 19, 2003 #11

    wolram

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    http://elf.gi.alaska.edu/
    this page maybe of interset bottom of page related topics

    In addition to sprites and jets, but possibly related, there have recently been observed from space two other types of unexpected emissions that appear to originate in thunderstorms. Short duration (~1 ms) gamma ray (>1 MeV) bursts of terrestrial origin have been detected by the Compton Gamma Ray Observatory . They are observed to occur over thunderstorm regions, and their source is believed to lie at altitudes greater than 30 km. Finally, extremely intense pairs of VHF pulses (Trans-Ionospheric Pulse Pairs, or TIPPS (TIPP Paper Postscript Source ) originating from thunderstorm regions, but some 10,000 times stronger than sferics produced by normal lightning activity, have been observed by the ALEXIS satellite.
    cheers wolram.....
     
  13. Jul 21, 2003 #12

    Ivan Seeking

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    See what happens when you ask a simple question...
     
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