[Henry Pool (OP)]

I think you people still do not understand the nature of light. It cannot get "absorbed" in the atmosphere. Let me give you this example: Let us say that on earth with a lightmeter I measure the light by holding the meter in a certain direction, at a certain time of the day on a) a sunny day and b) on a cloudy day. On the cloudy day I notice a) it is cooler and b) it is darker. So where did the difference in light go? yes, because of the nature of the water (in gas form!) the clouds reflected most of that light, including the (hot) infra red light. This light cannot "stay" in the atmosphere! It has to move.. It is reflected back to space. Likewise carbon dioxide is opaque to infra red, so some of the infra red that would otherwise hit earth is reflected back to space. Without giving me any figures on on how much cooling and warming one layer of carbon dioxide would cause, the debate about it is pointless..... 

[Madidus_Scientia]

It's amusing you think we don't understand the nature of light.

This light cannot "stay" in the atmosphere!

The light is converted to heat energy when absorbed.

[Bored chemist]

I think it's Henry who doesn't understand things. He writes stuff like" because of the nature of the water (in gas form!) the clouds" but we know that the  water in a cloud is a bunch of tiny drops of liquid.

Clouds of liquid can reflect light quite well- but the issue here is CO2 and it's always a gas in the Earth's atmosphere so Henry's "point" is a total red herring.
Until he learns the basic facts there's not a lot of point putting numbers to them.

[Henry Pool (OP)]

I cannot believe that you people do not understand that there is a limit to how many photons can be taken up by a certaine amount of a substance. I have a definition here of the greenhouse effect by Elmar Uherek:
"Greenhouse gases (CO2, O3, CFC) absorb infrared radiation from the surface of the Earth and trap the heat in the troposphere.  If this absorption is really strong, the greenhouse gas blocks most of the outgoing infrared radiation close to the Earth's surface".
I think let us keep the discussion of the role of the water & water vapor out of it, as it only confuses things. What we are really only interested in is the effect of the carbon dioxide which happens to be completely diffused into the air @ ca. 0.035%
Keyword that he used in his definition is "blocks". That is the word that I also used. This is where the infra red keeps coming back to earth instead of going outwards. Now he is the only scientist so far who actually agrees with me that there is or that there may be some cooling effect(s) by carbon dioxide. In fact, to quote from his e-mail to me, he says:
"This (web) page (i.e. these are his own studies into the cooling effect of carbon dioxide in the upper atmosphere) does not consider the amount of infrared radiation from the sun coming from the top of the atmosphere. It would be interesting to find out how much is coming bottom up compared to top down. Honestly, I do not know it. I am sorry, that I cannot do a sound inquiry in this issue, since I am a bit overworked and additionally became father last week.I hope, my ideas helped a bit how to proceed with further inquiry". End of quote.

Now if you will go back to my report, to my "findings", you will note that this is exactly the whole point that I am trying to make. This is what the whole issue is about.I am saying top down infra red is probably more than bottom up because
1) The total energy coming from the sun is 47-49% in infra red (for 12 hours per day)
2) We only have 30% of earth that can radiate infra red  (for 24 hours per day).
3) So for the carbon dioxide to have any impact, the infra red from earth in 8 hours (= ca.1/3 of 24 hours) must match that of the sun in 12 hours.
4) From where I am (stand), I can feel that what we get in infra red from the sun is a lot more than what earth emits.
So now you understand why I am not worried anymore about the carbon dioxide.
Again, unless someone has actual figures, debating it further is really quite pointless....

[Bored chemist]

"I cannot believe that you people do not understand that there is a limit to how many photons can be taken up by a certaine amount of a substance. "
Unfortunately for your rather odd beliefs there is no such limit.
Since we tend to prefer reality we don't believe in that limit.
You don't seem to have grasped what the bloke you cited actually said.
"If this absorption is really strong, the greenhouse gas blocks most of the outgoing infrared radiation close to the Earth's surface".
I have underlined a bit for you.
If the gas stops the heat getting out the earth's temperature rises.
Greenhouse gases cause warming.

Incidentally, there is yet another thing you haven't understood; you are not a good IR meter.
So when you say "From where I am (stand), I can feel that what we get in infra red from the sun is a lot more than what earth emits. "
there's a simple explanation.
You are hotter than the earth, but colder than the sun.
When you fact the sun you emit IR towards it but it sends a lot more IR (and visible light) your way so the net effect is that your face warms up.

When you face the earth you emit more IR to it than it sends you so there's no net warming of your face.

If you were trying to prove that the sun is hotter than the earth then this set of observations would help.
It says absolutely nothing about the greenhouse effect.
It does, on the other hand, show that as usual, you have not understood what you are saying.
Incidentally that rubbish about "12 hours a day" shows that you don't understand that the sun and earth emit radiation all the time.

Whatever the figures may be, debating nonsense is, as you say, pointless.
Feel free to stop.

[Henry Pool (OP)]

sorry, BC, you lost me now. Just go back a a few steps to see what the argument was about. I never said that I do not believe in the mechanics of the greenhouse theory. But according to the same mechanics there must also be a cooling effect. Surely, going from the top to the bottom is the same as going from the bottom to the top (of the atmosphere) for infra red. And everywhere the CO2 content is the same. So it looks to me that the cooling effect is as much or even more then the warming effect. But admittedly I do not have the figures. I think it is you who has brought nothing but nonsense in this discussion so far. Feel free to stop "helping" me. You are only fooling yourselves.

[Bored chemist]

"Surely, going from the top to the bottom is the same as going from the bottom to the top"
No, going from hot to cold is not the same as going from cold to hot.
The sun emits visible light which can pass through the atmosphere whereas the earth tries to emit IR which doesn't.

[Henry Pool (OP)]

Quote: "Direct sunlight ......includes infrared (47% share of the spectrum), visible (46%), and ultra-violet (only 6%) light". Apparently 98.7% of the UV is blocked by the ozone.Let's keep that out of the equations. The reality is that only 30% of earth's surface is able to emit infra red. A lot of the visible light comes through but a large portion of that is also reflected, especially by clouds and on the poles and mountains and by the seas. You only have to study the pictures from earth from outer space to see what happens. Anyway, a maximum of a third of that 46% visible and a maximum of a third of that Infra red 47% part hits upon us.
But, as I said, whether all of that would be reflected as infra red by earth?     
I doubt very much that it would be possible for earth to emit as much infra red radiation as  what we get from the sun.

[Madidus_Scientia]

During the day more energy comes in than goes out. The planet warms. The more greenhouse gases there are, the less energy that gets out. The warmer the planet.

I'm not sure if I can simplify it any further

[Henry Pool (OP)]

sorry MS, I think you also lost the thread of what we were discussing.
Like me, some scientists accept(ed) that carbon dioxide also causes cooling but they believed that per square meter solid ground area (of earth) the infra red was brighter (i.e. more) than what the sun puts on that square meter. There may be some truth in that. But I think that would be ignoring the cooling effect that the carbon dioxide causes above our oceans: I say that without the carbon dioxide in the atmosphere even more heat would be dumped into our oceans. Remember that infra red cannot escape the water. It can only heat it, as it has been doing for thousands of years.
So what is really important is to know the total output in infra red of earth per square meter per time unit compared to the total input of infra red from the sun per square meter per time unit. I am pretty sure that if you average it out over the whole surface area of earth, you will find that the infra red coming from earth is a lot lower than that coming from the sun.
that means: carbon dioxide is good for life and good for global cooling.

[Bored chemist]

OK, for a start lets drop the nonsense about day and night.
It is always daytime on earth and it is always nighttime.

The earth reflects about 39% of the light that falls on it- Vangelis wrote a song about it.
http://en.wikipedia.org/wiki/Albedo_0.39
so it's simply wrong to say "A lot of the visible light comes through but a large portion of that is also reflected, especially by clouds and on the poles and mountains and by the seas"
Most of it isn't reflected.
Most of it is absorbed and warms the earth up a bit. The earth re-emits heat as IR. If the atmosphere is full of CO2 then this gets in the way of the outgoing CO2.
Because the earth can't lose heat so easily, it warms up.

You have provided data on the radiation from the sun. Here's a rough breakdown of the energy emitted by the earth.
IR-  practically all of it
Visible light- virtually none
UV- even less

The earth gains energy from the sun- the only way it can lose it is by emitting IR. If something gets in the way of that IR the earth gets warmer.
This isn't complicated; why won't you understand it?

Incidentally, Re "Remember that infra red cannot escape the water."
Nonsense- Water emits IR perfectly well.


You say "So what is really important is to know the total output in infra red of earth per square meter per time unit compared to the total input of infra red from the sun per square meter per time unit. "
Well, you are nearly right. The two figures you need are
1 how much energy comes in from the sun (and it doesn't matter a tinker's cuss what wavelength it comes in as because, once it is absorbed, it will come out as IR because the earth isn't very hot)
and
2 the rate at which that area can lose heat by radiation.
(which will be all in the IR because the earth isn't hot enough to give out visible light or UV)
The input is pretty near constant- the sun's not changing much.
The output can be altered if we put something in the way- like extra CO2.
(strictly you need to add heat generated within the earth too but that's not going to change much anyway so we can ignore it here.

BTW, I am thinking of going through every one of your posts on this and collecting all the assertions that you have made that are simply not true. To save me the trouble, could I ask you not to bother posting any more trash? All I would ask is that you don't waste time saying things like "the clouds are made of gas" or "Remember that infra red cannot escape the water"
They, and the associated corrections, just clutter up the site.
It would be better if you checked that what you post is factually correct before posting it. This is, after all, meant to be a scientific site.

[Henry Pool (OP)]

First of all, let me say that it was not me who did not understand the mechanism or the proposed mechanism of the greenhouse effect. We wasted a lot of time on that.
Anyway, thanks for that page on the albedo, from there I was able to jump somewhere else and get a figure for the total infra red emitted by earth, it is 230W/m2.
Apparently it is defined as 288 K (15 C) min. I did not realize this. I was used to having infra red ovens for curing of paint, so I always associate IR with much higher temperatures.
So indeed, apparently above water there can also be infra red. I do apologize for not knowing or picking up on that before.
Now, the sun apparently puts a total of 1366 W/m2 on earth.
The IR range 760nm to 500 um (micrometer) equals 46% of the energy; so that would be 628 W/m2.
Now 628>230. I expected this result. This proves to me that my findings as reported earlier are correct.
The cooling effect of carbon dioxide must be greater than the warming effect...

[Henry Pool (OP)]

Sorry, I was going with BC's assumption not to worry anymore about day and night. That was wrong!
QUOTE:
The Earth receives a total amount of radiation determined by its cross section (π·RE²), but as it rotates this energy is distributed across the entire surface area (4·π·RE²). Hence the average incoming solar radiation, taking into account the angle at which the rays strike and that at any one moment half the planet does not receive any solar radiation, is one-fourth the solar constant (approximately 342 W/m²). At any given moment, the amount of solar radiation received at a location on the Earth's surface depends on the state of the atmosphere and the location's latitude"
 e.g. here in Africa I was probably right in saying or feeling that the IR from the sun is more than that of earth.
So now 157< 230. If all these figures are correct it means that the warming effect due to the carbon dioxide is more probable. 

[Henry Pool (OP)]

I am sure of the value of the emittance from the sun onto earth. I have various sources for that. However, I am not too sure anymore about the 230 coming from earth. It seems to me this was calculated from the albedo of earth which was taken at about 0.3. Some sources mention an albedo of 0.3. One source that I have puts the albedo of earth at 0.36 +- 0.06. If we went for the top value we have an albedo of 0.42. In that case the value of 230 would already change to 0.58 x 342=198. But obviously if this is how the earth's emittance was calculated or estimated then this is is not particularly good science for our research here.
We have to try and get a measured value for earth's IR emittance that is independant of the value that we got for the sun.

[Bored chemist]

"Apparently it is defined as 288 K (15 C) min. "
no it's not- or at least that's not how most people define it.

The day vs night bit isn't important because the earth is big and so it averages temperature changes out quite a bit. Changes on a day to day basis or even a season to season basis are not significat from the point of view of climate change.

The mean irradiance at the earths outer atmosphere is about 1.3KW/m^2
Some of that is reflected- for the visible bit it is about 39%
We simply don't have any information about the IR but I guess we can assume it's similar (unless anyone has the real numbers)
That incoming radiation is averaged over the earth's surface to give, as Henry calculated about 342 W/m^2 and, since about 39% is reflected about 61% is absorbed
That gives about 210W/m^2
I say "about" because the number varies by about 7%
The true figure is somewher between about 204 and 225
Henry also provided a figure of about 230W/m^2 for the loss (By IR)
You may note that the difference between these figures for the incoming and outgoing energy are rather similar. That's not a shock. If they were not then the earth would heat up or cool down until they were balanced.
The earth also generates heat because of the decay of radioactive materials in the rocks.
This explains the reamaining dozen or so w/m^2


The incoming and outgoing energy balance.

The question is what happens if you make it more difficult for the IR to escape.
The answer is that the planet warms up a bit so it emits more IR so that (even with part of it reabsorbed by the CO2) the system still balances.

Henry has assumed that, because these numbers match, one must have been calculated from the other.
He doesn't understand that they are bound to match because the earth has been here long enough to reach (close to) equilibrium and any other result would be a breach of the principle of the conservation of energy.

[Henry Pool (OP)]

thanks BC.It does makes sense. But I have been thinking and I am worried we might have been going about this in a wrong way. I think we have to go back to the actual infra red spectrum of CO2, see where it absorbs, i.e the wavelengths, then take the energy from the sun between these two particular wavelengths where CO2 absorbs, from the solar constant (I think can calculate this from the tables that I found!).But after this, we must get the radiance from earth between these two wavelengths where CO2 absorbs, ... now where and how do I get this information?

[Bored chemist]

"thanks BC.It does makes sense. "
It always did.

I could find a copy of the IR spectrum of CO2 and that would give you the information on how much IR is absorbed at what wavelengths.
But it doesn't matter, if some of the IR (at watever wavelength) is blocked on the way out then the world heats up a bit.
The spectra involved would make a difference to how big the warming is but it would be warming anyway.

[Henry Pool (OP)]

Ok. I am still looking at all of this. I need more time. Here is an interesting graph:
http://faculty.engineering.ucdavis.edu/jenkins/courses/EBS216/SolarEnergy/SolarEnergy.pdf
The blue line is the energy we would get without an atmosphere, yellow line is what we get with it. Look at the combined efforts of carbon dioxide and water vapor: it keeps us cool!!
I think it will be difficult to get a more quantifiable result as this, unless somebody puts some money into some real research.

[Henry Pool (OP)]

Somehow the link does not work anymore. How can I attach the graph here?

[Bored chemist]

Just because you have a graph doesn't mean we will believe it.
There's already been a whole lot of research done and, like common sense, it says that the greenhouse effect causes warming