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Has the greenhouse effect been falsified?
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Greenhouse effect has been falsified
"[T]he influence of so-called greenhouse gases on near-surface temperature - is not yet absolutely proven. In other words, there is as yet no incontrovertible proof either of the greenhouse effect, or its connection with alleged global warming.
This is no surprise, because in fact there is no such thing as the greenhouse effect: it is an impossibility. The statement that so-called greenhouse gases, especially CO2, contribute to near-surface atmospheric warming is in glaring contradiction to well-known physical laws relating to gas and vapour, as well as to general caloric theory.' (Heinz Thieme)
At a glance
Did you know that in the late 1700s, astronomers calculated the Earth-Sun distance to within 3% of the correct average value of 149.6 million kilometres? That was an incredible feat for the time, involving painstaking measurements and some pretty serious number crunching, with no help from computers.
Why is that mentioned here, you might ask. It's because not long afterwards, in the 1820s, French physicist Jean Joseph Baptiste Fourier made another crucial calculation. He worked out that at this distance from the Sun, Earth should have been an uninhabitable iceball.
Fourier suggested there must be some kind of insulating 'blanket' within the atmosphere. By the end of that century, Eunice Foote and John Tyndall had proved him quite correct through their experiments with various gases and Svante Arrhenius quantified matters in 1896, even calculating the effect of doubling the concentration of CO2. They had it largely figured out all that time ago.
If you are still sceptical about the existence of a greenhouse effect on Earth, there's something you can do in order to double-check. Go to the moon.
Well, you don't have to go personally, thanks to remote sensing and lunar landings by both unmanned and manned craft. Such intrepid expeditions mean we have a stack of data regarding lunar properties. The moon is pretty much the same distance from the Sun as Earth, but the lunar atmosphere is so thin it may as well not exist at all. There's virtually nothing to inhibit heat transfer, in or out.
In addition, the Moon turns but slowly on its axis compared to Earth. While a mean Solar day here lasts 24 hours, on the Moon it lasts just under a month. You get the best part of a fortnight of relentless Solar heating followed by a similar period of cooling in the long lunar night. So what's the temperature?
In the vicinity of the Lunar equator, daytime temperatures eventually reach a boiling hot 120oC. During the lunar night, that temperature drops away to -130° C. No atmosphere so no greenhouse effect. All that heat accumulated in the long lunar day just shoots straight back out into space. Nights on Earth may be much shorter, but nevertheless in the absence of a greenhouse effect they would be brutal.
Our approximately Earth-sized near neighbour, Venus, closer to the Sun, is different again. It has a massive dense atmosphere mostly consisting of CO2 with a side-helping of sulphur dioxide. Surface atmospheric pressure on Venus is so great that on Earth you would need to go a kilometre down in the ocean to find similar values. The planet rotates very slowly on its axis so days and nights are even longer than on the Moon. But unlike the Moon, Venus is always a hot place. Its surface temperature is over 450oC, day or night. An extreme greenhouse effect maintains that heat.
Remember: no atmosphere, no greenhouse effect and unimaginably cold lunar nights - but the example of Venus shows you can also have too much of a good thing. Earth really is a Goldilocks planet.
Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!
Further details
Some climate science deniers dispute the existence of the ‘greenhouse effect’. This is where their arguments lurch from silly - to beyond silly. The greenhouse effect keeps the surface temperature of Earth approximately 33oC warmer than it would be if there were no greenhouse gases in the atmosphere. In other words, without the greenhouse effect, Earth would be effectively uninhabitable.
Fig 1: The greenhouse effect is an analogy not meant as a scientific model of effect; hence, detractors have attacked the wrong model. (source: jg)
How do we know for sure this effect is real? The principle is demonstrated through basic physics, because a bare rock orbiting the Sun at the Earth-Sun distance (mean = 149.6 million kilometres) should be far colder than the Earth actually is. This was realised by Jean Joseph Baptiste Fourier in the 1820s, but the explanation why it was the case was not forthcoming for a few more decades. Fourier considered it to have something to do with the atmosphere having the properties of a kind of insulating blanket.
The existence of Fourier's hypothetical 'blanket' was confirmed by the experimental studies done by Eunice Foote and John Tyndall, working independently on either side of the Atlantic in the 1850s. Foote's results were announced at the 1856 meeting of the American Association for the Advancement of Science, and published in the American Journal of Science and Arts in the same year. The paper was entitled, ‘Circumstances Affecting the Heat of the Sun’s Rays’, with an excellent recent review by Ortiz and Jackon (2020). A key passage is as follows:
“The highest effect of the sun’s rays I have found to be in carbonic acid gas. An atmosphere of that gas would give to our earth a high temperature; and if as some suppose, at one period of its history, the air had mixed with it a larger proportion than at present, an increased temperature from its own action, as well as from increased weight, must have necessarily resulted.”
In his 1861 paper, “On the absorption and radiation of heat by gases and vapours, and on the physical connexion of radiation, absorption, and conduction” (PDF here), Tyndall stated:
“Now if, as the above experiments indicate, the chief influence be exercised by the aqueous vapour, every variation of this constituent must produce a change of climate. Similar remarks would apply to the carbonic acid diffused through the air; while an almost inappreciable admixture of any of the hydrocarbon vapours would produce great effects on the terrestrial rays and produce corresponding changes of climate.”
Tyndall had in his own words identified methane as an even more potent greenhouse gas than CO2. Later that century, Swedish scientist Svante Arrhenius put the numbers on the relationship between greenhouse gas concentrations and surface temperatures. He was able to calculate the effect of doubling the CO2 concentration in the air. The result was a globally-averaged figure of 5-6°C of warming, not that dissimilar to modern values.
Empirical Evidence for the Greenhouse Effect
We only have to look to our moon for evidence of what the Earth might be like, without an atmosphere and greenhouse effect. It's not as though we're short of data about our satellite. While the moon’s surface reaches 120oC (248oF) in direct sunlight at the equator during the long lunar day, when it gets dark the temperature drops down to a frigid -130oC (-202oF).
Since the moon is virtually the same distance from the sun as we are, it is reasonable to ask why at night the Earth doesn’t get as cold as the moon. The answer is that, unlike the Earth, the moon has no insulating blanket of greenhouse gases, because it has virtually no atmosphere at all. Without our protective atmosphere and its greenhouse effect, the Earth would be as barren as our lifeless moon. In the absence of the heat trapped overnight in the atmosphere (and in the ground and oceans) our nights would be so cold that few plants or animals could survive even a single one.
Conclusive evidence for the greenhouse effect – and the role CO2 plays – can also be seen in data from the surface and from satellites. By comparing the Sun’s heat reaching the Earth with the heat leaving it, both things we can measure with great accuracy, we can see that less long-wave radiation (heat) is leaving than arriving. Since the 1970s, less and less radiation is leaving the Earth, as the levels of CO2 and other greenhouse gases build up. Since all radiation is measured by its wavelength, we can see that the frequencies being trapped in the atmosphere are the same frequencies absorbed by greenhouse gases.
To conclude, disputing that the greenhouse effect is real is to attempt to discredit centuries of science, the laws of physics and indeed direct observation. Without the greenhouse effect, we would not even be here to argue about it.
Last updated on 26 November 2023 by John Mason. View Archives
The often-quoted 255K black body temperature of the earth is wrong and the 33K GHE is overstated. This is due to the albedo being too high in the calculation which is meant to show what the temperature would be if the earth had no atmosphere at all.
However, the calculation falsely uses the albedo when an atmosphere exists, completely ignoring the fact that if there is no atmosphere, there are no clouds. Using a conservative estimate that 50% of albedo is attributed to clouds, this decreases the albedo from 0.3 to 0.15 resulting in a black body temperature of approximately 268K, reducing the GHE to 20K.
However, there would be further impacts on ice and water, and a more realistic albedo when there is no atmosphere at all is 10%, as others have postulated. This leads to a black body temperature of approximately 271K (-2.15C) and a theorized GHE effect of 17K, just over half of what was previously estimated.
[BL] Return of another sock puppet.
CTS @176 :
an iceball Earth (at 255K or 271K) has how many clouds?
Have you really thought this through . . . and published?
CTS @176... "The often-quoted 255K black body temperature of the earth is wrong..."
That which is asserted without evidence can be dismissed without evidence.
Is it healthy to pander to crazy sock-puppet nonsense by discussing 'what-if' ideas when the sock-puppet is wedded to a 'surely it is' idea?
The idea that the existing GHE can be attributed to 50% water vapour, 25% cloud and this forced by 25% CO2 which thus attributes cloud as a warming agent does overlook the full impact of cloud on planetray albedo and which could be used to calculate cloud as a cooling agent.
The sock-puppet @176 suggests a cloudless Earth would see albedo drop from 30% to 15%, the latter being roughly the Moon's effective albedo which would suggest the Moon woud have an average temperature of 267K. However the measured temperature of the Moon averages at 201K and this because the Moon rotation is so slow that it sheds massive amounts of energy during its day with Moon equatorial temperatures reaching 390K.
Of course, the Earth spins fast enough to prevent such a large duirnal range and if there had never been CO2 to form a GHE, there would never have been oceans to slow it down from its 4 hour day back when the Earth-Moon began.
But unlike the Moon, there is a lot of water on Earth and the albedo of ice is high. That is reduced by the dust which would cover the ice on a GHE-free Earth but albedo would remain high, and perhaps higher than today. De Vrese et al (2021) suggests the albedo of 'meteoric ice' is 65% which, if the Earth's albedo, would indicate a 250K Earth and a GHE of 38K.
An argument used to explain Earth-surface/Earth-lower-troposphere warming to the general public is that some gases (called greenhouse gases) in the Earth's atmosphere "trap heat" thereby increasing temperature. In the public's mind, "trapping heat" goes hand-in-hand with increasing temperature and so the phrase serves its intended purpose: make it believable to the public that atmospheric greenhouse gases will warm the Earth's surface.
This almost ubiquitously used claim (“the Earth's surface is warmed by-heat-trapping greenhouse gases”) is invalid because heat cannot be trapped—i.e., an adiabatic wall does not exist in nature. If heat can’t be trapped, any and all claims that rely on the existence of heat-trapping material or trapped heat constitute misinformation.
I believe the phrases "trapped heat" and "heat trapping" are used to incorrectly explain a physical process in a way that will resonate with the general public. Imagine the effect on the general public if in all articles that mention "heat trapping," after every appearance of the phrase ("heat trapping" or "trapped heat") a parenthetical qualifier followed that said "heat cannot be trapped, but we use 'trapped heat' because it 'kind of' describes what is going on." Do you think such a qualifying caveat would have any effect on the public's acceptance of the greenhouse gas theory of warming?
Reed Coray @180,
Just one question ...
What 'easily understood term' do you suggest should be used to name what happens when the increased concentration of certain types of molecules in the atmosphere results in an increased temperature at the surface of the planet?
One Planet Only Forever at 04:48 AM on 28 March 2025
"You wrote: Just one question ...
What 'easily understood term' do you suggest should be used to name what happens when the increased concentration of certain types of molecules in the atmosphere results in an increased temperature at the surface of the planet?"
My answer is: "I'm not sure an 'easily understood term' exists, but if I had to pick one it would be 'Surface Warming Occurs To Establish Energy Rate Equilibrium (ERE) Within The Earth/Earth-atmosphere System.'
A System is in ERE if the rate energy enters the system (or any sub-element of the system) is equal to the rate energy leaves the system (or the designated sub-element) adding. The temperature distribution of a system in ERE does not have to be uniform. The only requirement for ERE is that energy (which in the case of the Earth's surface is heat) neither accumulates nor decreases within the system or any sub-volume of the system.
Adding material (e.g., gases) to a system in ERE will likely cause temperature changes within the system. Eventually these temperature changes will reach a new ERE steady state.
In the case of the Earth/Earth-atmosphere system, to achieve a new ERE state when gases are added to the atmosphere, the temperature distribution within the system must change. One component of that temperature distribution is the Earth's surface temperature, which may go up or down. The direction and amount of temperature change can be determined either experimentally or theoretically.
If your theoretical estimate of Earth surface warming requires the existence of 'trapped heat' (i.e., your theoretical argument is that Earth surface warming will occur because some gases 'trap heat' within the lower troposphere), then your theoretical argument is nonsense because heat can't be trapped.
As I said, I'm not sure an 'easily understood term' exists for Earth surface temperature change. Because of this, I don’t like simple explanations. They are too likely to be mislead.
Reed Coray
@ 180 / 182 :
Whoa ! Whoa there, Reed Corey.
Please remember the KISS principle.
You say: "to explain ... warming to the general public ..." . But explaining to the general public ~ is not going to happen if a reference to the topic of climate change goes on to a multi-paragraph declaration of complex atmospheric physics. That would be tiresome and insulting to the general public.
"We the people" deserve a simple one-liner description (wherever that is appropriate). A "greenhouse effect trapping heat" is a fair enough and accurate enough description for those of us who use colloquial English. It is a reasonable analogy, for practical purposes.
Sure, in a scientific discussion by experts and would-be experts, you can bring in topics like lapse rates; thermalizations; entropy; heat balance; infra-red radiation; etcetera. But in common sense parlance, "trapping" heat by means of a pane of glass or a wool blanket ~ is not a misleading or dishonest analogy.
Those who choose to go deeper into the semantics and the physics . . . are free to do so, at their leisure. However, for public discussion of the practical politics of countering the modern rapid global warming ~ simplicity is a courtesy and a duty.
Reed Coray @ 180, 182...
Well, I'm pretty sure that OPOF's request for an easily understood term is not answered by an "explanation" that take some 270 words...
...but you harp on the claim that "heat can't be trapped". You go into a long monologue about the dynamics of energy transfer, the concept of dynamic equilibrium (although you do not use the word dynamic), etc. And you complain that simple explanations can be misleading or represent misinformation.
I hate to break it to you, but every simple explanation ever offered on any subject will require leaving out details. Any analogy offered to help explain a complex system to someone unfamiliar with those details wlil only be able to represent part of that complex system - the analogy will be similar in some respects, and wlll differ in others. The "simple explanation" will always be a starting point for a more detailed explanation.
For example, the "can't trap heat" argument could also be applied to any other system where energy is being added and temperature is rising. Let's take a pot on a stove, or a house heated by a furnace. Putting a lid on the pot makes the temperature rise faster. Closing the windows in the house makes the house get warmer (for the same furnace output). In each case, there is more thermal energy (AKA "heat") in the pot or house. In each case, a simplified description is that adding the lid or closing the windows "traps heat". In each case, there is more to it, but in each case the "traps heat" explanation is a reasonable starting point.
You admit that "an easily understood term" may not be possible. Yet you criticize the use of simplified explanations because they are incomplete. Every simple explanation is incomplete. Every simple explanation leaves something out, and therefore may be subject to misunderstanding (especially if someone is determined to misunderstand or misrepresent it). The same applies to complex explanations - also subject to leaving things out, possible misunderstanding or misrepresentation (especially if someone is determined to misunderstand or misrepresent it).
By setting a standard of "simple is misleading because it is simple", you are requesting perfection in the simplified presentation. This is what is known as setting impossible expectations, which is an unreasonable position to take. It is also a common one in the climate change discussion space:
Methinks thou doth protest too much.
It's also worth noting that the word "trap" is barely used at all in the OP that we are commenting on. In the Basic tab, it appears twice. Once in relation to comparing the earth (with an atmosphere) to the moon (no atmosphere), and once in relation to the atmosphere trapping radiation. In the Intermediate tab, the word "trap" does not appear in the OP at all.
Reed Coray's complaint about overly-simplified explanations of "trapping heat" seem rather oddly placed under a blog post that gives a lengthy discussion of the greenhouse effect (which is of itself a poor term, as is explained in the OP!). Complaining that something should not be done when it does not occur in the OP starts to look like someone is complaining just for the sake of complaining.
The comments section here is intended to discuss the science presented in the original posts. This is explained at the top of the Comments Policy. As a new user, it behooves Reed Coray to actually read the posts he wants to comment on.
Reed Coray @182,
As Bob Loblaw suspects, you have not answered my question.
In addition to the responses by Bob Loblaw and Eclectic, I observe that even the detailed explanation you provided is incomplete. It should address the source of energy input to the earth-atmosphere system and what happens to that energy within the system.
A significant percentage of incoming (entering – and there is a reason I bold this term) solar energy passes through the ‘greenhouse gases’ in the atmosphere and is absorbed or reflected by the features of the ‘surface of the planet’. The reflected solar radiation exits out to space through the atmosphere as easily as it entered. However, absorbed energy gets re-emitted in a form that is different from the solar radiation that enters the system. And the greenhouse gases make it harder for the energy emitted by the surface features to exit the system (leave out to space). Simply, and fairly accurately, greenhouse gases allow entry of the solar energy down to the surface but block the exit of heat emitted by the warmed surface back out to space.
The current on-line Oxford definition of the verb ‘trap’ is: catch (an animal) in a trap.
The related noun ‘trap’ is defined as: a device or enclosure designed to catch and retain animals, typically by allowing entry but not exit ...
Try to be more helpful and careful. “The Earth's surface is warmed by heat-trapping greenhouse gases” seems to be an accurate ‘easily understood’ description of the result of greenhouse gases in the atmosphere. Trying to claim that the statement is a form of misinformation does not help improve efforts to increase public awareness and understanding of the problem. And that type of ‘poorly justified claim-making’ could be understood to be a form of misinformation (something that Bob Loblaw also noted in a different way).
Bob Loblaw at 00:12 AM on 29 March 2025
You wrote: " Every simple explanation leaves something out, and therefore may be subject to misunderstanding (especially if someone is determined to misunderstand or misrepresent it)"
It is true that simple explanations "leave things out," and are therefore susceptible to misintrepretation. But why include in a simple explanation something that isn't true? Doing that makes it more likely that the simple explanation will be misintrepreted.
For example, why not shorten your Earth surface warming simple explanation to: "atmospheric greenhouse gases act to warm the Earth's surface?" That's an even simpler explanation and doesn't contain a statement that isn't true. What does the caveat "trapping heat" add to the simple explanation other than make it more likely to be misintrepreted?
If your answer is that it makes it more likely that a reader will accept the greenhouse effect theory because he is familiar with connotations of the word "trap," then not only is your simple explanation misinformation, it is disinformation--i.e., information that is designed to mislead others and is spread with the intent to manipulate truth and facts.
Reed Coray @ 187:
Your assertion that you "can't trap heat" and that using the phrase "trap heat" is "not true" only makes sense if you create such a strict literal meaning to the words "trap heat" that is unjustified. In that context, nothing at all anyone ever says anywhere is "true".
...and I repeat what I said in #185: you are arguing a point that is barely mentioned in the OP. It seems as though you want to ignore the rest of the OP. You're just playing word games.
You also have ignored the part where I say that such simple explanations represent a starting point for further discussion/explanation. Such as the discussion and explanation that is contained in the rest of the OP.
Your accusations of an "intent to manipulate truth and facts" are unfounded, unsupported, and against the Comments Policy of this site. You are now cherry picking one phrase you want to use to attack the science, and using that to claim some grand conspiracy to deceive. You have now hit two more techniques of climate denial: