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Stellar spectra captured from ground based equipment needs corrections to remove atmospheric spectral noise. Is there an Internet site that shows specific amplitude and wavelength differences between an observed spectrum and a corrected stellar spectrum?

The Dec, 2011 issue of Astronomy, page 51 shows the interference of Earth's atmospheric spectra, but the figures do not have amplitude and wavelength data.

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I think the question is a little misleading. If you are taking long exposures of an stellar spectrum then the only "noise from the atmosphere" you have to account for absorption, refraction and dispersion, which is basically what Andrew answered (for more details see the works of Vacca, Cushing or Rayner, 2003, where they plot the spectrum that you are asking for I think).

However, if you are actually taking short exposures and want to correct for the real noise that produces changes on stellar spectra because of climate changes, probably talking of red noise, which have been a concern for years for photometry and is today being used in spectroscopy (see the work of Pont et al, 2005 for a short introduction).

If no answer is useful for you, maybe you'll have to give us details in what you want (and please, if you saw this on a magazine, post the link to the article or to some preprint that we could see in order to help you. For example, I'm not actually subscribed to the Astronomy magazine so I really don't know what figure caught your mind).

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The basic of atmospheric extinction, i.e. the part that is uniform worldwide, are explained here: http://www.asterism.org/tutorials/tut28-1.htm (basically geometric scattering)

The details will vary with time and geographic location- sodium lamp light pollution, molecular absorption lines, aerosols in the air, volcanic ash, the whole gamut. Really doing it right is a matter of ongoing research.

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Andrew, your answer addresses atmospheric extinction rather than atmospheric spectra that are the noise for stellar spectra observations from Earth-based instruments. As mentioned in my question, I was looking for a site illustrating a stellar spectrum as observed combined with atmospheric spectra (noise) and as would be seen above the atmosphere. – Mike Nov 20 '11 at 18:38
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By the way, the atmospheric scattering reference in your response was written by me several years ago as a tutorial for my astronomy club. – Mike Nov 20 '11 at 22:55
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You may find the information in this post enlightening (no pun intended): http://scienceblogs.com/startswithabang/2012/02/defeating_hubble_from_the_grou.php

It's about using http://en.wikipedia.org/wiki/Adaptive_optics to cancel out atmospheric interference.

This isn't necessarily an answer to your question but I can't comment yet.

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