All Questions
Tagged with absorption atmospheric-science
17
questions
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44
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What is the range of noon sun color temperature, when a light meter reports full expected sunlight (+/- epsilon)?
My question came from trying to find what uncertainty bounds, if any, I can assign to a color temperature sensor, without access to an artifact with a precisely calibrated output spectrum.
This leads ...
- 11
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1
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157
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What is the influence of humidity on NDIR $\rm CO_2$ measurements?
The Question
I would like to use an NDIR $\rm CO_2$ sensor to measure $\rm CO_2$ in the 0.1-3% range. However, in the course of my experiments, humidity may vary from ambient (50-60%) up to nearly 100%...
- 101
2
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1
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75
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Why we typically see no deeper into an atmosphere for an optical depth of 1?
In An Introduction to Modern Astrophysics (p.243), Carroll and Ostlie say that for a optical depth $\tau = 1$ the intensity will decline by a faction of $e^{-1}$.
$I_\lambda = I_{\lambda,0}e^{-\tau}$
...
1
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1
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955
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Absorption Spectra of Atmospheric Gases
From this previous Stackexchange question:
Is a detailed absorption spectrum available for carbon dioxide from 300-1100nm?
and this paper:
https://www.osti.gov/servlets/purl/1613653
as well as this ...
- 113
7
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152
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How can daylight have a higher colour temperature (e.g. 6500 K or D65) than sunlight in space?
Supposedly, daylight at midday has a colour temperature of 6500 K. This reference is also the standard for calibrating computer screens (that's how I fell into this). However, outside the atmosphere ...
-1
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1
answer
99
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$CO_2$ absoprtion bands in atmosphere and impact of increasing concentration levels
I have a question to do with this graphic and the CO2 absorption band highlighted with a red vertical line.
The image shows that nearly 100% of the IR energy in that band is absorbed in the ...
- 133
3
votes
6
answers
514
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How can atmospheric $CO_2$ absorption of infrared be 100% when its atmospheric concentration is 0.04%?
An absorption spectrum from high in the atmosphere of infrared radiation emitted from the earth, shows that for the 15µm wavelength there is almost complete absorption. This is attributed to ...
- 179
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101
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Two-photon absorption fluorescence of air
I'm wondering if there are any major constituents of air which are capable of undergoing two-photon absorption and ultimately fluorescing in the visible spectrum. The original wavelengths of the ...
- 51
2
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30
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Temperature profile of the atmosphere due to absorption by a gas [closed]
I want to observe the temperature profile of the atmosphere due to absorption by a gas such as water vapor. I know that optical thickness changes as the density of the gas changes with altitude in the ...
3
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1
answer
4k
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Why does the sun/moon appear red when there are fires?
Recently, in the United States, the moon and sun have become very deep red when they are near the horizon. The reason given for this is that there have been extensive wild fires in the Northwest. So, ...
- 4,494
3
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2
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3k
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How to see wind?
Is there a wavelength of light at which you could see air moving? I was thinking it would be amazing to put on a pair of goggles which enables you to see how air moves around across a landscape, while ...
- 185
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1
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2k
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Optimal laser wavelength for heating air
Lets say I want to heat air with laser,what wavelenght should I chose,ultraviolet,infrared or something in visible spectrum? To clarify,I want the laser beam to lose power and get converted to heat in ...
- 734
2
votes
1
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652
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How much air would be needed to block sunlight?
Was watching a sunset on the sea, I was wondering what would be a lower bound for the thickness of air needed to almost completely obscure the reddish light of the sun, or at least to make it ...
- 131
3
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1
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2k
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Why can't infrared rays go through the atmosphere?
Why can't infrared rays reach the earth? Why can't they pass through the atmosphere?
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1
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506
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Why do high altitudes have larger diurnal temperature variation than lower altitudes?
It seems like the lack of atmosphere should not be playing a role in the diurnal temperature variation because that's what makes it colder. Mountains are not that dry, usually.
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