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Effect of thickness of atmosphere on the incident light on land

  1. Oct 31, 2010 #1
    How would the whiteness of snow appear if Earth's atmosphere were several times thicker?

    I think it would appear red as most of the blue frequency light would be scattered before reaching the earth and the majority of light being reflected of the snow would be red.

    Am i right?
  2. jcsd
  3. Oct 31, 2010 #2


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    Whilst this must be an effect, I think the difference in absorption at the different frequencies, as well as the scattering, would have an effect in the spectrum of the light reaching the ground.
  4. Oct 31, 2010 #3
    Could you please be more detailed about the effects you were referring to in the above answer?
  5. Nov 1, 2010 #4


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    http://en.wikipedia.org/wiki/File:Solar_Spectrum.png" [Broken]
    If you look at this link it shows that atmospheric absorption modifies the spectrum (in the fine detail) of the incident Sunlight in addition to the effect of Raleigh scattering (the general trend). Absorption effects are more marked at non-optical frequencies, of course, with huge amounts of absorption of microwave frequencies by water vapour. Both effects on the optical bands would get more and more pronounced as the atmosphere gets thicker and thicker.
    I have a feeling that, in a thicker atmosphere, the effects of absorption by some of the more dense but more rare molecules (which collect more in the bottom layers) would be more marked than at the present atmospheric thickness and pressure. This would produce proportionally more noticeable colouring.

    I assume you are taking snow to be a good reflector of light at all wavelengths, producing what we would call 'white' with the Sun overhead. Our (brain) colour compensation circuits do a lot better than those in cameras and I have a feeling that we would very soon accept a modified version of this if we were to spend much time under a more dense atmosphere, in much the same way as we 'see' white things as white under tungsten and flourescent lights.
    Last edited by a moderator: May 5, 2017
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