World Leaders Producing 300,000 Tons of Carbon By Traveling To Climate Summit In Paris
- Thread starter Max E.
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CO2 cools in the sense that it causes the sun to heat a little less during the day.. This phenomenon is associated with the outer atmosphere and it has nothing to do with the greenhouse effect.
As you can see from the graph below, CO2 isn't completely transparent to solar radiation.
[the graph above is from : https://en.wikipedia.org/wiki/Sunlight]
The first thing you notice is that the sun approximates a black body radiator. The red here is what reaches the Earth and the Red and yellow together is what reaches the outer atmosphere. If you integrate the total area incorporated by the spectrum, you'll find that most of the radiation from the sun is in the infrared (heat) region. There is quite a bit in the visible region too, but not as much as in the infrared. There isn't much uv, thank goodness. (uv has enough energy to break chemical bonds! We don't want that.) If you integrate just the red area, you will find that the ratio of the visible to IR striking the Earth hasn't changed very much from the ratio of visible to IR in the incident solar emr. That's because in solar radiation reaching the Earth some of the IR has been filtered out by absorption but IR is poorly scattered, whereas none of the visible has been filtered by absorption but it is fairly efficiently scattered. Both absorption and scattering are active during daylight hours in shielding the Earth from the sun. This is a temperature lowering factor.
Now we know that all of the gaseous main components of the atmosphere are colorless. What this tells us is that they do not absorb visible light! None of them do! Yet look at the 400 to 700 nm region, that's the visible region of the emr spectrum. If the atmosphere does not absorb visible light then why is the red area in this region reduced from the net yellow and red combined. What this tells us is that this graph includes more than just absorption even though it is labeled as an absorption graph. Obviously some solar radiation shielding phenomena besides absorption is incorporated into this graph. That additional shielding phenomenon is mainly scattering -- the same phenomenon that makes the sky appear blue in the day and red, yellow or orange near sunset. Blue light is scattered to a greater extent then longer wavelengths. The difference between the yellow and red in the visible region as a function of wavelength is consistent with the drop in intensity of visible light reaching the surface being due to scattering. Shielding has the effect of making the Earth less hot during the day. CO2 shields by both absorption and scattering. What assumptions have been incorporated into the graph regarding water vapor content are not specified. And, of course, the very important daytime cooling effects of clouds, vertical convection, and wind driven evaporation don't show up in this graph.
So to your question, "how would CO2, transparent to sunlight, cool the day side of the moon?"
Let's start by recognizing that CO2 isn't completely transparent to sunlight, as the graph above nicely illustrates. There is some absorption in the IR region, and there is plenty of IR in sunlight. We assume that CO2 would function on our hypothetical moon the same way it does on Earth. During the day it is going to cool mainly by shielding due to scattering and absorption. Absorption is going to be a very weak phenomena, because as I have pointed out many times, CO2 is a poor IR absorber having only one fundamental IR active absorption band, an asymmetric stretch. This means it will be, by absorption alone, a poor shielding gas, and also I might add a poor greenhouse gas if its concentration is as low as it is on Earth. But its shielding via scattering during the day should be about as effective, or even more effective, than its shielding by absorption. (It scatters at shorter wavelengths than it absorbs at.) I used to think that CO2's warming via the greenhouse effect would probably exceed its overall shielding effect, but now this seems quite wrong to me. During the moon Day it will be net cooling because its shielding is due to both scattering at visible wavelengths and IR absorption, whereas its daytime green house effect is due only to absorption at lower altitude and not scattering. It does not scatter IR efficiently. On the dark side of the moon, however, where shielding isn't involved, it certainly will be warming by its weak greenhouse effect. And in our imagined moon atmosphere there is no water vapor and clouds to keep us warm a night; we are in a moon desert. We will have to depend on CO2's weak greenhouse effect to try and stay warm during the 13 Earth-day-long moon night. We are going to freeze to death!
"As you can see from the graph below, CO2 isn't completely transparent to solar radiation."
Yes pie, but it is mostly transparent to the bulk of it's energy which is in the shorter visible wavelengths. Then that short wavelength energy is changed to long wavelength (heat) energy as it hits the earth. This re-radiated long wavelength energy is then intercepted by atmospheric CO2.
Thus the net effect is that CO2 acts to keep the earth warmer than it would be without it.
This is basic climate science 101, which you must have skipped over at some point on your way to Libertarian la la land.
See how I explained that in a few choice words? You should try that sometime. Of course, then the wow gee wiz BS factor would not be as high.
So if we kept adding this weak greenhouse gas indefinitely in our hypothetical Moon experiment, could we expect the day side of the Moon to continue growing cooler and cooler?CO2 cools in the sense that it causes the sun to heat a little less during the day.. This phenomenon is associated with the outer atmosphere and it has nothing to do with the greenhouse effect.
As you can see from the graph below, CO2 isn't completely transparent to solar radiation.
[the graph above is from : https://en.wikipedia.org/wiki/Sunlight]
The first thing you notice is that the sun approximates a black body radiator. The red here is what reaches the Earth and the Red and yellow together is what reaches the outer atmosphere. If you integrate the total area incorporated by the spectrum, you'll find that most of the radiation from the sun is in the infrared (heat) region. There is quite a bit in the visible region too, but not as much as in the infrared. There isn't much uv, thank goodness. (uv has enough energy to break chemical bonds! We don't want that.) If you integrate just the red area, you will find that the ratio of the visible to IR striking the Earth hasn't changed very much from the ratio of visible to IR in the incident solar emr. That's because in solar radiation reaching the Earth some of the IR has been filtered out by absorption but IR is poorly scattered, whereas none of the visible has been filtered by absorption but it is fairly efficiently scattered. Both absorption and scattering are active during daylight hours in shielding the Earth from the sun. This is a temperature lowering factor.
Now we know that all of the gaseous main components of the atmosphere are colorless. What this tells us is that they do not absorb visible light! None of them do! Yet look at the 400 to 700 nm region, that's the visible region of the emr spectrum. If the atmosphere does not absorb visible light then why is the red area in this region reduced from the net yellow and red combined. What this tells us is that this graph includes more than just absorption even though it is labeled as an absorption graph. Obviously some solar radiation shielding phenomena besides absorption is incorporated into this graph. That additional shielding phenomenon is mainly scattering -- the same phenomenon that makes the sky appear blue in the day and red, yellow or orange near sunset. Blue light is scattered to a greater extent then longer wavelengths. The difference between the yellow and red in the visible region as a function of wavelength is consistent with the drop in intensity of visible light reaching the surface being due to scattering. Shielding has the effect of making the Earth less hot during the day. CO2 shields by both absorption and scattering. What assumptions have been incorporated into the graph regarding water vapor content are not specified. And, of course, the very important daytime cooling effects of clouds, vertical convection, and wind driven evaporation don't show up in this graph.
So to your question, "how would CO2, transparent to sunlight, cool the day side of the moon?"
Let's start by recognizing that CO2 isn't completely transparent to sunlight, as the graph above nicely illustrates. There is some absorption in the IR region, and there is plenty of IR in sunlight. We assume that CO2 would function on our hypothetical moon the same way it does on Earth. During the day it is going to cool mainly by shielding due to scattering and absorption. Absorption is going to be a very weak phenomena, because as I have pointed out many times, CO2 is a poor IR absorber having only one fundamental IR active absorption band, an asymmetric stretch. This means it will be, by absorption alone, a poor shielding gas, and also I might add a poor greenhouse gas if its concentration is as low as it is on Earth. But its shielding via scattering during the day should be about as effective, or even more effective, than its shielding by absorption. (It scatters at shorter wavelengths than it absorbs at.) I used to think that CO2's warming via the greenhouse effect would probably exceed its overall shielding effect, but now this seems quite wrong to me. During the moon Day it will be net cooling because its shielding is due to both scattering at visible wavelengths and IR absorption, whereas its daytime green house effect is due only to absorption at lower altitude and not scattering. It does not scatter IR efficiently. On the dark side of the moon, however, where shielding isn't involved, it certainly will be warming by its weak greenhouse effect. And in our imagined moon atmosphere there is no water vapor and clouds to keep us warm a night; we are in a moon desert. We will have to depend on CO2's weak greenhouse effect to try and stay warm during the 13 Earth-day-long moon night. We are going to freeze to death!
If any of these nitwits were actually serious about addressing the dreaded climate change, we'd be building hundreds of nuke plants, mandating natty gas for 18 wheelers plus all fleet vehicles, and pouring everything we have into fuel cells for cars. We're not, which means one of two things. These politicians are dumber than fuck, or there isn't any real problem to solve. But oh the money and power to be gained on the never ending campaign trail.
Yup.
The conservatives of our nation that vote Republican/Tea Party are dumber than fuck as well as the politicians that they vote for.
I don't see any Democrats pushing for nuke plants or natty gas fuel mandates. The technology is there, it's safe and ready to go. What's the hold up other than some tired old ideology based on a misguided and ill informed movie from the 70's?
Such a mandate would require rep cooperation, which they're not going to get, since "the problem doesn't exist", so why would they waste time trying?
As for natural gas, power generation has been converting to it for years now. Fleets? I don't know, but I'd like to see more. The problem is infrastructure, which no private enterprise is going to take the lead and expense on.