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Quantum Physics behind the greenhouse effect.

  1. Jul 3, 2015 #1
    I read that when heat passes through the glass of a greenhouse it gets absorbed by the earth inside the greenhouse. The Earth reflects this heat but these rays are of longer wavelength so it bounces off the glass and inturn heats the greenhouse more. Now the heat coming from the sun is also absorbed by the Earth and it reflects the heat of a longer wavelength. This longer wavelenth heat cannot pass through the carbon dioxide in the atmosphere and is in turn reflected.
    just like the green house.

    How does all this relate to quantum physics?
  2. jcsd
  3. Jul 3, 2015 #2
    The absorption and emission are quantum processes.

    You can find out more here: http://hyperphysics.phy-astr.gsu.edu/hbase/mod5.html

    Reflection is different. The entire process of the Greenhouse effect, which you describe doesn't involve reflection, only absorption and emission. The CO2 absorbs and re-emits light, rather than reflecting it, as in the case of glass.
    Last edited: Jul 3, 2015
  4. Jul 4, 2015 #3
    I agree that absorption and emission can be described by quantum mechanics, but that would be like trying to understand how a car works by quantum mechanics. Why would you do that when classical physics works better with less uncertainty? o_O
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