Guest Post by Reed Coray
On Dec. 6, 2011 12:12 am Lord Monckton posted a comment on a thread entitled Monckton on sensitivity training at Durban that appeared on this blog on Dec. 5, 2011. In that comment he wrote:
“First, it is not difficult to calculate that the Earth’s characteristic-emission temperature is 255 K. That is the temperature that would obtain at the surface in the absence of any greenhouse gases in the atmosphere. Since today’s surface temperature is 288 K, the presence as opposed to absence of all the greenhouse gases causes a warming of 33 K”.
Since I’m not sure what the definition of the “Earth’s characteristic-emission temperature” is, I can’t disagree with his claim that its value is 255 K. However, I can and do disagree with his claim that 255 K is “the temperature that would obtain at the surface in the absence of any greenhouse gases in the atmosphere”.
When computing the Earth’s surface temperature difference in “the presence as opposed to the absence of all greenhouse gases”, (i) two temperatures (A and B) must be measured/estimated and (ii) the difference in those temperatures computed. The first temperature, A, is the temperature of the Earth’s surface in the presence of an atmosphere that contains both greenhouse gases and non-greenhouse gases. The second temperature, B, is the temperature of the Earth’s surface in the presence of an atmosphere that contains non-greenhouse gases only–i.e., an atmosphere that contains non-greenhouse gases but is devoid of greenhouse gases.
For temperature A almost everyone uses a “measured average” of temperatures over the surface of the Earth. Although issues may exist regarding the algorithm used to compute a “measured average” Earth surface temperature, for the purposes of this discussion I’ll ignore all such issues and accept the value of 288 K as the value of temperature A (the temperature of the Earth’s surface in the presence of an atmosphere that contains both greenhouse gases and non-greenhouse gases).
Thus, we are left with coming up with a way to measure/estimate temperature B (the temperature of the Earth’s surface in the presence of an atmosphere that contains non-greenhouse gases only). We can’t directly measure B because we can’t remove greenhouse gases from the Earth’s atmosphere. This means we must use an algorithm (a model) to estimate B. I believe the algorithm most commonly used to compute the 255 K temperature estimate of B does NOT correspond to a model of “the temperature of the Earth’s surface in the presence of an atmosphere that contains non-greenhouse gases only”. As will be evident by my description (see below) of the commonly used algorithm, if anything that algorithm is more representative of a model of “the temperature of the Earth’s surface in the presence of an atmosphere that contains both greenhouse gases and non-greenhouse gases” than it is representative of a model of “the temperature of the Earth’s surface in the presence of an atmosphere that contains non-greenhouse gases only.”
If I am correct, then the use of 255 K in the computation of the Earth surface temperature difference with and without greenhouse gases is invalid.
Although there are many algorithms that can potentially lead to a 255 K temperature estimate of B, I now present the algorithm that I believe is most commonly used, and discuss why that algorithm does NOT represent “the temperature of the Earth’s surface in the presence of an atmosphere that is devoid of greenhouse gases”. I believe the algorithm described below represents the fundamental equation of radiative transfer for the Earth/Sun system assuming (a) an Earth absorption albedo of 0.3, and (b) an Earth emissivity of 1.
(1) The “effective temperature” of the Sun [i.e., the temperature of a sun-size spherical blackbody for which the radiated electromagnetic power (a) is representative of the total solar radiated power, and (b) has a power spectral density similar to the solar power spectral density] is approximately 5,778 K.
(2) For a spherical blackbody of radius 6.96×10^8 meters (the approximate radius of the sun) at a uniform surface temperature of 5,778 K, (a) the total radiated power is approximately 3.85×10^26 Watts, and (b) the radiated power density at a distance of 1.5×10^11 meters from the center of the blackbody (the approximate distance between the center of the Sun and the center of the Earth) is approximately 1,367 Watts per square meter.
(3) If the center of a sphere of radius 6.44×10^6 meters (the approximate radius of the Earth) is placed at a distance of 1.5×10^11 meters from the center of the Sun, to a good approximation the “effective absorbing area” of that sphere for blackbody radiation from the Sun is 1.3×10^14 square meters; and hence the solar power incident on the effective absorbing area of the sphere of radius 6.44×10^6 meters is approximately 1.78×10^17 Watts (1.3×10^14 square meters x 1,367 Watts per square meter).
(4) If the sphere of radius 6.44×10^6 meters absorbs electromagnetic energy with an “effective absorption albedo” of 0.3, then the solar power absorbed by the sphere is 1.25×10^17 Watts [1.78×10^17 Watts x (1 – 0.3)].
(5) A spherical blackbody (i.e., a spherical body whose surface radiates like a surface having an emissivity of 1) of radius 6.44×10^6 meters and at a temperature 254.87 K (hereafter rounded to 255 K) will radiate energy at the approximate rate of 1.25×10^17 Watts.
(6) If independent of the direction of energy incident on a sphere, the surface temperature of the sphere at any instant in time is everywhere the same, then the sphere possesses the property of perfect-thermal-conduction. Thus, for (a) an inert (no internal thermal energy source) perfect-thermal-conduction spherical body of radius 6.44×10^6 meters and uniform surface temperature 255 K whose center is placed at a distance of 1.5×10^11 meters from the center of an active (internal thermal energy source) spherical blackbody of radius 6.96×10^8 meters and uniform surface temperature 5,778 K, and (b) the inert perfect-thermal-conduction spherical body (i) absorbs electromagnetic energy with an effective absorption albedo of 0.3, and (ii) radiates electromagnetic energy with an emissivity of 1 then the perfect-thermal-conduction inert spherical body at temperature 255 K will be in radiation rate equilibrium with the active spherical blackbody at temperature 5,778 K. If the phrase “inert perfect-thermal-conduction spherical body of radius 6.44×10^6 meters” is replaced with the word “Earth,” and the phrase ” active spherical blackbody of radius 6.96×10^8 meters and uniform surface temperature 5,778 K” is replaced with the word “Sun”, it can be concluded that: If (a) an “Earth” at temperature 255 K is placed at a distance of 1.5×10^11 meters from the “Sun” and (b) the “Earth” (i) absorbs electromagnetic energy with an effective absorption albedo of 0.3, and (ii) radiates energy with an emissivity of 1, then the “Earth” will be in radiation rate equilibrium with the “Sun.” For the above conditions, the temperature of the “Earth” in radiation rate equilibrium with the “Sun” will be 255 K.
This completes the algorithm that I believe is commonly used to arrive at an “Earth’s characteristic-emission temperature” of 255 K, and hence is used to compute the 33 K temperature difference.
Even ignoring the facts that (1) it is incorrect to use the “average surface temperature” when computing radiation energy loss from a surface, and (2) in the presence of an atmosphere, (a) the blackbody radiation formula may not apply, and (b) blackbody radiation from the surface of the Earth is not the only mechanism for Earth energy loss to space (the atmosphere even without greenhouse gases will be heated by conduction from the Earth surface and both conduction and convection will cause that thermal energy to be distributed throughout the atmosphere, and the heated atmosphere will also radiate energy to space), the problem with using the 255 K temperature computed above to determine the difference between the Earth’s temperature with and without greenhouse gases is that the effective Earth absorption albedo of 0.3 used to generate the 255 K temperature is in part (mainly?) due to clouds in the atmosphere, and atmospheric clouds are created from water vapor, which is a greenhouse gas.
Thus an effective absorption albedo of 0.3 is based on the presence of a greenhouse gas–water vapor. It is illogical to compute a difference between two temperatures both of whose values are based on the presence of greenhouse gases and then claim that temperature difference represents the temperature difference with and without greenhouse gases. Without water vapor, there won’t be any clouds as we know them. Without clouds, the effective absorption albedo of the Earth will likely not be 0.3, and hence without the greenhouse gas water vapor, the Earth’s surface temperature in the absence of greenhouse gases is likely to be something other than 255 K. Thus, the 255 K “Earth characteristic-emission temperature” as computed using the algorithm above is NOT relevant to a discussion of the Earth surface temperature difference for an atmosphere that does and an atmosphere that does not contain greenhouse gases. Only if 0.3 is the effective absorption albedo of the Earth in the presence of an atmosphere devoid of all greenhouse gases is it fair to claim the presence of greenhouse gases increases the temperature of the Earth by 33 K.
Because clouds reflect a significant amount of incoming solar power, without water vapor I believe the effective absorption albedo of the Earth will be less than 0.3. If true, then more of the Sun’s energy will be absorbed by an Earth whose atmosphere is devoid of greenhouse gases than by an Earth whose atmosphere contains clouds formed from the greenhouse gas water vapor. This implies a higher Earth surface temperature in the absence of water vapor than the “Earth’s characteristic-emission temperature of 255 K”.
For an effective absorption albedo of 0, the temperature of the Earth in radiation rate equilibrium with the Sun will be approximately 278.64 K (hereafter rounded to 279 K). If this value is used as the Earth temperature in the presence of an atmosphere devoid of greenhouse gases, then it can be argued that the presence of greenhouse gases introduces a warming of approximately 9 K (288 Kelvin minus 279 K).
In summation, using the simplified arguments that I believe are also used to arrive at the 33 K temperature difference (i.e., assumed perfect-thermal-conduction Earth, blackbody Earth emission, greybody Earth absorption with an effective absorption albedo between 0 and 0.3, and ignoring atmospheric radiation to space for an Earth atmosphere devoid of greenhouse gases), I conclude the presence of greenhouse gases in the Earth’s atmosphere increases the Earth’s temperature by somewhere between 9 K and 33 K. Thus, I believe the claim that the presence of atmospheric greenhouse gases increases the temperature of the Earth by 33 K is based on an argument that has little relevance to the Earth’s temperature in the presence of an atmosphere devoid of greenhouse gases; and hence at best is misleading and at worst incorrect.
Note: Upon first publication – the guest author Reed Coray was accidentally and unintentionally omitted.
To those discussing how the earth may have broke out of the snowball epoch, this fairly current research is most germain, and not at all irrelevant to the topic of greenhouse gases and earth’s average temperature:
http://www.springerlink.com/content/6262k8x02pvkm772/
Thierry says:
December 26, 2011 at 7:22 am
“Everything concerning the fictitious 33°C greenhouse gases effect has been definitively explained and rebutted by Gerlich & Tscheuschner (2009) in “Falsi fication Of The Atmospheric CO2 Greenhouse E ffects Within The Frame Of Physics” (http://arxiv.org/abs/0707.1161)
This value comes from a wrong use of the Stefan-Boltzmann law (flux imposing local temperature, which is wrong) involving an over simplified planet model (no atmosphere, infinite conductivity, no rotation). The real temperature would be -129°C.
Therefore, this -18°C has no meaning at all.”
On must explain why temperature probes buried a meter or more deep in lunar regolith at 45 degrees latitude record a year-round constant temperature of -23C while the same probe buried a meter deep at the latitude on the earth records a year-round temperature of 11C.
Something is making the earth ~33C warmer than the moon. This is not only a theoretical calculation but an observation as well since the early 1970’s when two separate Apollo missions buried temperature probes in lunar regolith from surface to 3 meters deep that radioed the temperatures back to NASA for the next several years. Gerlich et al are certainly entitled to an opinion on why the earth is so much warmer than the moon but they aren’t entitled to their own facts where their “fact” is that the earth isn’t really warmer than an approximate black body lacking a dynamic ocean/atmosphere at the same distance from the sun.
I agree that the oceans are black at normal incidence, but at lower angles water reflects a large fraction of SW radiation. This is just a part of the complications involved in this whole debate–which ends up with numbers that have little utility as far as I can see. The temperature of 255K depends on such things as whole-earth equal intensity of outgoing LW radiation, but that is far from the actual case.
If one would like an “average” radiation temperature, then what I suggested earlier,
makes more sense.
In what manner do his notions violate energy conservation? There are many ways to sum or integrate to a given number. For instance, the Moon, which many people have used as example here, the subsolar point is quite hot, and the rest is pretty damned cold. The average temperature of 250K achieves energy conservation, but is not reflective of the actual distribution, which also obeys energy conservation, at all.
I agree generally with you, but occasionally Gerlich & Tscheuschner frame points in such a narrow manner that they fall prey to the same flaws they critique.
DirkH says:
December 26, 2011 at 7:13 am
So O2 and N2 will keep their energy forever even if in the vacuum of space, as they can’t radiate anything?
Bingo!
Quote from the article: “However, I can and do disagree with his claim that 255 K is “the temperature that would obtain at the surface in the absence of any greenhouse gases in the atmosphere”.
Maybe this website sheds somewhat more light on this topic:
http://www.ems.psu.edu/~fraser/Bad/BadGreenhouse.html
It is really not hard to understand, IF you think the right way. If there was not something like the ‘greenhouse effect’ we all would be dead, unless we all could live at 255K. Much confusion arises from the term ‘Greenhouse effect’, which sadly is a misnomer.
SLAY THE SKY DRAGON——END OF ARGUMENT!!!
David says:
December 26, 2011 at 8:50 am
“Please consider answering my three questions in the following paragraph.
So at perihelion we have a permanent loss to space of ? W/2m SWR, due to increased NH albedo, and, in the SH a temporary loss of SWR to the atmosphere, as at perihelion the SWR is falling on far more ocean, where it is absorbed into the oceans for far longer then if that SWR fell on land. Do these balance (unlikely) or is the earth gaining or losing energy during perihelion???
The TOA seasonal flux should tell us and climate models should accurately predict the observation. Does anyone know if the climate models accurately predict what happens seasonaly on earth?”
i) and ii) I don’t think they ever balance precisely. There is always a net gain or net loss and the system adjusts accordingly to try to maintain balance. Always a negative system response to ANY forcing whether that be solar, oceanic, volcanic, aerosols or CO2.
iii) The climate models do include seasonal variations. Where they collapse is in identifying and quantifying trends beyond normal seasonal variability.
Alan Stratham,
you said: “You wrongly claim that you can’t use an average temperature to calculate radiation losses.”
I must disagree. Whenever you have a non linear relationship between two variables, you have to be very careful about averaging the independent variables.
Suppose for sake of argument, you have half the surface area with temperature T1, and half with temperature T2. What would be the radiative flux from each area? Ignoring Stefan-Boltzmann’s constant, you would have F1 = T1^4 and F2 = T2^4.
Total flux would be Area1 x T1^4 plus Area2 x T2^4. Since each area is half of the total area A, total radiative flux = 1/2A(T1^4 + T2^4).
Now let’s find the average temperature Tav. Tav = 1/2(T1 + T2).
Flux density = (Tav)^4 = 1/16(T1 + T2)^4.
Multiplying this by the total area A, total radiative flux = 1/16A(T1 + T2)^4.
You can expand that if you like, but I think you’ll find it is not equal to 1/2A(T1^4 + T2^4).
Based on the mathematics, I suggest that the author is correct in claiming that you can’t use average temperature to calculate radiation loss.
“those discussing how the earth may have broke out of the snowball epoch, ”
Where is the evidence that it actually happened ?
That is, with NO open water at the equator.
R. Gates says:
December 26, 2011 at 9:54 am
“To those discussing how the earth may have broke out of the snowball epoch, this fairly current research is most germain, and not at all irrelevant to the topic of greenhouse gases and earth’s average temperature:”
http://www.springerlink.com/content/6262k8x02pvkm772/
Thanks Gates. You did good. That research confirms my own conclusion which I arrived at all by my lonesome, about the effect of volcanic ash on deglaciation.
I would also remind you that James Hansen himself, earlier in his career, pointed out that accumulation of black soot from dirty smokestacks and unfiltered old diesel engines travels up to a few thousand kilometers from its source then comes to rest on NH permanent snow cover accelerating the melt of sea ice and glaciers as it gets darker and darker every single year. In fact back when he wasn’t so afraid of the facts getting in the way of his agenda he assigned black soot up to half the blame for global warming.
This was, of course, before it was determined that the United States needed to be the scapegoat for global warming because, you see, since the Clean Air Act of 1964 the U.S. has not been emitting much black soot. But Europe with its abiding love for antique diesels in its transportation fleet (ya gotta love how those old diesel engines just keep going and going and going like the energizer bunny) and poor countries who cling to slash & burn agriculture and cook with anything combustable, continue to emit copious amounts of black soot which then goes on to melt things like the Himlayan Glacier. But we can’t go blaming Europe and poor undeveloped countries for these things… that’s just not politically correct. So the CO2 bogeyman and attendant water vapor amplification were invented so the US could be made to appear to be the bad guy.
Isn’t that just precious?
John Brookes,
“OK, that seems like a pretty silly argument. Take a look at Mars. I think Mars would be pretty close to earth without ghgs. No oceans, no vegetation, no ice no animals, just lots of red dirt. But Mars does not have an albedo of 0, it has an albedo of 0.25 – not too disimilar to that of Earth, and certainly a value which will get you closer to 255K than 279K..”
Mars is nothing like Earth. Earth is covered by 70% water which lowers albedo and would lead to an equilibrium temperature closer to 279k than 255k.
Lars P., thoroughly enjoyed reading you recent comment in tips¬es. You should re-post it here, not link, for general consideration by the many who are digging to bury the pseudo-science surrounding this very subject. I found yours very relevant.
David Springer,
You and most of the other responders do not “get it”. The ASSUMPTION WAS MADE by Monckton that if there were no greenhouse gases, AND THAT THE ALBEDO WAS 0.3, what the result would be. This is not the case for real oceans, since with oceans there always is present clouds and greenhouse gases. The model Monckton described is an idealized one that can’t have real oceans, or you could not reach the albedo stated. You are confusing the assumptions stated with the actual surface, which violates the simplified model stated. When doing simplifying analysis, you have to pay attention to what is said.
Does CO2 increase the temperature inside real greenhouses due to radiation?
Isn’t in point of fact the greenhouse effect in greenhouses a result of convection?
Doesn’t CO2 in point of fact play little or no role in the average temperature of real greenhouse?
Doesn’t the EPA and IPCC claim that atmospheric CO2 warms due to the exact same effect that warms real greenhouses?
Why if CO2 has a warming effect, is climate change not called global warming?
So, where is the experimental evidence that an atmosphere in which convection is not restricted by some sort of artificial cover will in fact behave like a real greenhouse in which convection is artificially restricted?
Where is the controlled experiment that demonstrates that a doubling of a trace amount of CO2 will in point of fact significantly increase average temperatures over a 24 hour period in any container? Not simply when the sun is shining, but also when the sun is not shining, to remove the thermal difference between CO2 and air.
If such an experiment has been done under controlled, double blind conditions, where are the results?
Has anyone done a vaguely realistic model of the earth representative of land/water spacial distribution and daily rotation a) without an atmosphere b) with a nitrogen atmsophere c) with water vapor and independantly variable albedo – given the contraversial nature of cloud.
That would be a better to start a model on. Starting a model based upon a flat static disc cannot evolve beyond its innacurate assumptions; rather like assuming a spherical horse.
More on a greenhouse gassless atmosphere. I’m reiterating what other’s have pointed out earlier:
The atmosphere would pick up heat by conduction with the earth’s surface.
The heat would drop off the higher you get in the atmosphere due to conservation of energy.
When the planet reached equilibrium, the energy lost by conduction from earth’s surface to the atmosphere would equal the net energy picked up by conduction from earth’s atmosphere.
Net radiation from the sun to earth’s surface would equal net radiation from earth’s surface back to space.
In the real universe there’s no such thing as a completely non-greenhouse atmosphere- all gases radiate in SOME frequencies. Depending on the densities of the different gases making up an atmosphere, these different gases would have different “effective radiation heights”, in the atmosphere, giving differernt greenhouse effects.
In the real universe there’s no such thing as a perfect black body.. All surface temperatures are
hotter than a black body giving off the same amount of radiation.
In the real universe, there’d be no free oxygen in an atmosphere without life, There’d be no life on a planet without water, so the argument about the effective temperature without greenhouse gases would be moot..
Lars P. says:
December 26, 2011 at 9:39 am
R. Gates says:
December 26, 2011 at 9:03 am
“one side of the planet would be boiling hot and one side freezing cold, as there’d be no greenhouse gases or oceans to modulate that “average””
The earth is a sphere that is spinning no way to have one side boiling hot and one side freezing cold – what you say does not make sense R. Gates, sorry.
______
I guess then that the moon, which is also a spinning sphere, would not have a boiling side and freezing side? But it does. The essential point is that the oceans and greenhouse atmosphere prevent a strong diurnal temperature variation. The oceans provide the primary heat “sink” of the planet and the greenhouse atmosphere provides a transport mechanism for the heat.
There are two things wrong with the normal formula used. 1. The idea of an average temperature using the 255 W/m^2. It can be shown that much of the NH up To 45N in the summer gets near 700 W/m^2. The troplcs near 1000 all year. 2. IR in the range CO2 emits (15 micro) back to the earth has no ability to do work so cannot heat anything.
Further there are no examples of gases doing anything other than dissipating heat. Our lives depend on this fact.
Sent from my new Christmas gift tablet. Please forgive spelling errors etc. as I get used to it.
Stephen Wilde says:
December 26, 2011 at 9:28 am
“I’m not convinced that there has ever been a snowball Earth. As I understand it there has always been an ice fee area either side of the equator.”
I’m not convinced either but the fact remains that it was close enough so that the distinction between slushball and snowball is academic for what we’re concerned about. Ice ages happen. We must somehow incorporate that into the hot water bottle theory. The way I do that is by keeping in mind that the hot water bottle only covers 70% of the earth’s surface.
Also keep in mind that as ice grows that 70% shrinks. The ocean’s shorelines retreat as more and more surface water is locked up in ice. That’s yet another positive feedback that works to take the ocean further and further out of the equation.
“So all we have is an extreme form of ice age with the ice moving down across more of each hemisphere than is usual.”
Glaciers at sea level in the tropics doesn’t seem fairly characterized by “more than usual”.
“Over the 4 billion year history of the Earth I am unsurprised that such things happened from time to time. The most likely cause would be large changes in the level of solar activity”
There is zero evidence for large changes in the level of solar activity. There are a zillion class M stars at all stages of their life cycles for us to look at and relatively speaking a class-M star like ours is before it becomes a red giant in its cups is one of the most constant dependable things in the universe. Large changes like that would leave fingerprints in the geologic column as well and they aren’t there. Unless there is strong evidence otherwise we must assume the sun is no different than other star like it and its constancy is dependable to a fault.
“for whatever reason with a very negative polar oscillation spreading polar air equatorward and cool oceans failing to resist. Your ‘perfect storm’ suggestions are plausible too.”
You’re just guessing about vague somethings. I cited events that are know to happen with frequencies that are known on average as well. Milankovitch cycles are calculable. Supervolcanoes happen every several million years. Asteroid strikes likewise. The latter two are not predictable with current knowledge as individual events but over geologic spans of time a predictable number of events occurs. It’s almost inevitable that a perfect storm of such events happens now and then. In fact I’m wondering right now how many Pinatubos it would take in succession to end the Holocene Interglacial. The Milankovitch alignment is just getting more favorable for glaciation over the next few thousand years and it appears the so-called Modern Maximum in solar magnetic activity has closed out and if Svensmark is right that’s going to help cool things off. Maybe one more Pinatubo is all it would take right now. I’m just sayin’ we don’t know what causes ice ages with certainty but we are certain they do happen.
So the water cycle never did stop despite vast areas of ice cover and in due course the water cycle regained its power once more.
R. Gates says:
“…Thus, were one to suggest we remove all the CO2 from the atmosphere (in addition to killing all the plant life) we’d also see all the water vapor condense out over time as the earth continued to cool, and we’d return to a snowball earth in fairly short order.”
Thanks for pointing out how ridiculous and dangerous it is for the U.S. EPA to treat CO2 as a pollutant and for the U.S Supreme Court to uphold their argument. CO2 sustains life on this planet. The idea that it is a “pollutant” and thus doesn’t belong in our atmosphere at all is suicidal.
R. Gates,
Thanks for the link to the snowball earth paper. The main points to summarise are:
1) CO2 levels of even 0.2 bar (200,000 ppm) are not sufficient to end glaciation.
2) Dark particles from super volcanoes would be needed in addition to 0.2 bar of CO2.
3) Models diverge at high levels of CO2.
4) The models themselves already contain the assumption of high sensitivity to CO2.
5) Nobody knows what actually ended snowball earth.
R. Gates says:
December 26, 2011 at 10:27 am
I guess then that the moon, which is also a spinning sphere, would not have a boiling side and freezing side? But it does.
_______________________
What?
Dave Springer says:
December 26, 2011 at 6:06 am
“If I am correct, then the use of 255 K in the computation of the Earth surface temperature difference with and without greenhouse gases is invalid.”
Yes of course it is. It’s the earth without an atmosphere or ocean and an albedo of zero. The average temperature of the moon is 250K. It has an albedo of 0.15.
=============================
Sigh, you’re saying it like this because the AGW meme is that ‘greenhouse gases’ excludes oxygen and nitrogen. Another discussion with everyone talking at cross purposes..
Firstly, before AGWScience Fiction began playing around with words and changing definitions, the Earth’s Greenhouse WAS THE WHOLE OF THE EARTH’S ATMOSPHERE, therefore, all the gases within it are greenhouse gases, and, that means some 96% oxygen and nitrogen, around 4% water, around 1% argon and the rest trace…
Earth without an atmosphere, without its real greenhouse, which is real greenhouse with windows.., the temp is around -18°C.
With the real Greenhouse, the whole of the Earth’s atmosphere including oxygen and nitrogen, the temp is 15°C.
So, the usual +plus 33°C of the AGWSF meme, is NOT from warmth added by AGWGreenhouse gases, but a straight comparison between Earth with and without its RealGreenhouseAtmosphere which includes oxygen and nitrogen as greenhouses gases.
How does that temp arrive?
Without the Water Cycle, but with the rest of the atmosphere in place, the Earth would be 67°C.
In other words, the greenhouse gas Water vapour cools the Earth by 52°C to get the temp back down to 15°C.
I do hope you can all see what the AGWSF memes have done here. Before going into arguments about albedos and comparisons with the Moon, first get out of the muddle created by AGWSF messing around with names and definitions.
ferd berple says:
December 26, 2011 at 10:13 am
“Doesn’t the EPA and IPCC claim that atmospheric CO2 warms due to the exact same effect that warms real greenhouses?”
No. Nobody is claiming that there’s a sheet of glass blocking convection of heat away from the surface.
Important question here is:
What drives ‘global’ temperatures (Land and Land & Oceans) ?
There are two major drivers:
1. The AMO with principal the ‘9 year’ oscillation, which is not related to the sunspot cycle (but not totally immune to it) , for more details see:
http://www.vukcevic.talktalk.net/theAMO-NAO.htm
see also:
http://berkeleyearth.org/pdf/berkeley-earth-decadal-variations.pdf
for the ‘9 year’ and importance of the AMO to global temps.
2. the Solar magnetic (Hale) cycle, not the sunspot one.
On this one I am writing more (on lines of the above linked as ‘theAMO-NAO’)
Hope everyone had a good Xmas