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Why does the earth behave like a giant magnet?

  1. Mar 21, 2005 #1
    i have posted these questions in the chemistry forum but I have not receive any replys. Perhaps I have posted the questions in a wrong forum.

    why does the earth behave like a giant magnet?

    why the hole in the ozone layer is above Antarctica but not polluted continents?

    in a fractional distillating column of liquid air, the 'exit' of oxygen gas (b.p. -183C) is below the argon gas (b.p. -186C). However, when the liquid air encounters the 'exit' of oxygen gas which is at -183C, the argon also boils. So we cannot seperate the oxygen and argon.
    What's wrong with my concept?

  2. jcsd
  3. Mar 22, 2005 #2
    The molten outer core of the Earth is thought to have big rotation convection cells, transmitting the generated heat from the inside out. That molten iron may be slightly ionized and consequently have a electrical charge.

    Since rotating convection cells also rotate the electrical current each convection cell may generate a huge magnetic field. Since adjacent convention cells are supposed to counter rotate the respective magnetic fields are opposite in direction, cancelling each other almost, depending on small irregularities in those chaotic processes. The earth magnetic field is supposed to be a resultant field of all those counter rotating convection cells.

    Now it should also be clear that smal changes in the convection cells could have large effects for the Earth magnetic field, one field a little strong another a little weaker and the complete magnetic polarity may flip from North to South.

    This is the geo-dynamo hypothesis.
  4. Mar 22, 2005 #3
    Atmospheric ozone is constantly generated under IR light of the sun and it decays again due to all kind of chemical processes.

    Now: No sun - No ozone. And this happens at the poles every once and a while, It's called the arctic night. It's that simple.

    The last one seems to e not Earth related. Have no idea.
  5. Mar 24, 2005 #4


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    UV light, isn't it?

    related causes: Air movement in the stratosphere transports CFCs toward the poles. The colder atmosphere above the poles better retains the CFCs so that higher concentrations are available to react with the sun's rays upon the end of the arctic night.
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