The question—“Can you provide empirical measured proof of how much warming is caused by CO2?”—on its surface appears perfectly rational, even scientific. Yet, despite its appeal, it’s not just unanswerable with current methods—it also reflects a misunderstanding of how climate science works. And no matter one’s position in the climate debate, including those deeply skeptical of climate alarmism, it’s important to recognize why this question, as framed, is fundamentally flawed.
1. It Demands the Impossible: Controlled Experimentation on a Planetary Scale
The key issue is that it requests measured proof—in other words, direct empirical measurement of a variable in isolation. But Earth is not a laboratory. You can’t take one Earth, run it with 300 ppm CO₂, and another with 420 ppm, hold everything else constant (solar irradiance, ocean currents, volcanic activity, cloud cover, etc.), and then observe the difference in temperature.
Climate, by nature, is a complex, chaotic, coupled system. We can measure correlations, make inferences, and run models—but there is no laboratory setting where you can isolate CO₂ and “measure” its exact contribution to global mean surface temperature in the real world. Demanding that kind of empirical isolation is akin to asking for direct proof that one puff of a cigarette causes cancer—it’s an unreasonable standard for complex systems with multiple interacting variables.
2. Confuses Forcing with Attribution
CO₂ is a radiative forcing—an input to the climate system, not a direct output. What we do have, via satellite spectroscopy, are measurements showing CO₂ absorbing and re-emitting infrared radiation. We measure the “back radiation” impinging on ground stations. That’s measurable and uncontroversial. The effect size of this forcing, however, is not directly measurable in isolation. It is inferred through modeling and statistical attribution studies.
These studies attempt to assign fractions of observed warming to different causes—greenhouse gases, aerosols, solar variability, land use change, etc. They rely on climate models and statistical methods, not isolated laboratory measurements. So while you can ask how much warming is attributed to CO₂ based on models and assumptions, you cannot measure it directly.
For those chafing at the word “modeling“, it is through modeling that we convert satellite measurements of brightness into global temperatures. i.e. UAH 6.1.
3. It Plays Into the Hands of Alarmists by Oversimplifying the Debate
Ironically, asking for “measured proof” of CO₂-caused warming as a rhetorical trap often backfires. It allows climate activists to claim skeptics “don’t understand science” because, technically, the question is malformed. It allows them to redirect the conversation toward a debate about “settled science” at the molecular level (CO₂ absorbs infrared radiation), which is not where the real debate lies.
The serious skeptical position doesn’t hinge on denying radiative physics, but on questioning how much warming will result, how models perform, how feedbacks behave, how reliable the temperature record is, and most critically—whether climate policies based on uncertain projections make any sense. That’s where the fight should be, not on strawman arguments about measured proof.
4. It Obscures the Real Problem: Model Dependence and Feedback Assumptions
Even the IPCC doesn’t claim that the warming due to CO₂ can be directly measured. Instead, they use “attribution studies” based on model simulations. For instance, they simulate Earth’s climate with anthropogenic CO₂ and without it, and then compare the model runs to observed temperatures.
The result is a claim like “most of the observed warming since 1950 is very likely due to human activity”—but this is a model-based inference, not a measurement. The feedbacks assumed in these models (especially water vapor and clouds) are poorly understood, and small changes in those assumptions cause large swings in warming predictions.
A reasonable skeptic would focus here: not on denying that CO₂ is a greenhouse gas, but on highlighting the immense uncertainty in how much warming results from doubling CO₂ (climate sensitivity), which still ranges widely in the literature. That’s the intelligent battlefront—not a demand for something no one can provide.
5. It Encourages a Binary Thinking Trap
Skeptics often fall into a trap by arguing as if the entire climate narrative hinges on the CO₂ molecule being harmful. But even if CO₂ is warming the planet somewhat, the real debate is over magnitude, timing, impacts, and cost-benefit tradeoffs of climate policies.
Demanding measured proof of how much warming is caused by CO₂ invites a yes/no answer, when in reality the issue is one of probability distributions, confidence intervals, and uncertainty. This plays right into the absolutist thinking that dominates mainstream climate rhetoric.
Ask Smarter Questions—Because the Data Isn’t That Smart
Demanding measured proof of how much warming is caused by CO₂ is a rhetorical dead end—not because it’s unreasonable to seek evidence, but because it betrays a misunderstanding of what’s empirically measurable in a planetary climate system. The question collapses under its own demand for impossible precision in a noisy, chaotic, and multifactorial system.
A far more productive—and scientifically grounded—skepticism targets the soft underbelly of the climate consensus: the assumptions, uncertainties, and measurement issues underpinning the entire narrative.
Start with the temperature record itself. Long-term surface temperature series suffer from significant reliability issues. Stations have aged, moved, been surrounded by urban development, and upgraded with different instrumentation—all of which can introduce inhomogeneities and artificial trends. Adjustments to the raw data are often opaque and poorly justified, raising questions about how much warming is real versus “corrected” into existence.
Then there’s the far greater uncertainty in estimating global variables like ocean heat content—a metric central to claims of “unprecedented warming.” Before ARGO floats were deployed in the early 2000s, ocean temperatures were measured by a ragtag mix of ship intakes and bathythermographs, yielding sparse, uneven, and inconsistent data. Even now, ARGO floats only sample a small fraction of the ocean volume and don’t reach deep enough to detect long-term thermal trends with high confidence.
On top of this shaky empirical foundation, climate modelers layer their assumptions about radiative forcing, feedbacks, and cloud behavior to produce projections decades into the future—projections which have consistently overestimated warming in the short term.
So rather than asking for something that can’t be measured—like isolated proof of CO₂’s warming effect—skeptics should keep the focus on what can be measured, and on how poorly. Ask:
- How have the temperature data been adjusted, and what impact do those adjustments have?
- How sensitive are climate models to initial conditions and subjective parameter tuning?
- What are the error margins in ocean heat content estimates over time?
- Why do historical reconstructions rely so heavily on modeled reanalysis rather than direct observation?
- Are mitigation policies cost effective?
- What unintentional harm can be caused by mitigation policies.
- Why aren’t the benefits of increased CO₂ used in calculations of effects on society?
This is where honest, disciplined skepticism belongs—not in demanding a measurement that physics and Earth system complexity simply won’t allow, but in pointing out the wobbly scaffolding on which sweeping, costly policies are being erected, assumptions, uncertainties, and modeling limitations that underlie the entire edifice of climate policy. That’s where skepticism can be scientifically rigorous, effective, and intellectually honest.
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just not answerable?
Maybe a thousand years from now?
A thousand years from now it is most likely that the present interglacial will be ending and earth’s biggest worry will be that New York, Chicago, Scotland and much more will be trying to figure out ways to stop the encroaching glaciers.
That and the millions of Canadians moving south of North Dakota
Half of all Canadians already live south of North Dakota
At that point, the USA can have us in canada as 51st state because we’re all moving to Mexico
Even then probably not. But, if we get Disclosure about UAPs and aliens, maybe an alien from a civilization millions of years more advance- might have better models. 🙂
Hopefully, 1000 years worth of experimentation will give future scientists a better understanding of the feedbacks in the climate system. (I doubt we will ever have a “perfect” understanding, but it is possible to improve the current understanding.)
Also future computers should have more memory and more powerful processors which would allow calculations using smaller grid cells.
As a result, the uncertainty would be smaller.
Uncertainty can never be eliminated.
Do i see the ‘ if only we have better computers we can figure this out’ at work here?
The uncertainty will indeed be smaller and can never be eliminated…but…
I dont think computers will ever significantly eliminate the basic uncertainty inherent in the system. I consider it therefor best to concentrate on things like extreme weather predictions, volcanic eruptions etc. I feel the physics crowd have a tendency to get stuck in a mathematical hole. It comes with the territory…
“The uncertainty will indeed be smaller . . .”
Not if the atmosphere is chaotic.
Maybe we should try to prove that Navier-Stokes equations are dynamically stable. Without this result we cannot be sure that discrete model calculations will ever be useful. This is a fundamental uncertainty that transcends mere uncertainty of measurements.
We could be the most advanced civilization. Somebody has to be first and there is no reason to assume we are not them.
We can’t assume anything about which we can’t sample- but the universe is 13+ billion years old and the sun and Earth are only 4+ billion so it’s easy to consider that there likely developed life elsewhere billions of years ago. But this is certainly one of the greatest mysteries. We could be the only life in the entire universe. Either way it’s mind blowing. I think a famous scientist said it better but I can’t remember who.
Don’t get me wrong, I hope there are many other cultures out there. The Star Trek junkie in me would be terribly disappointed otherwise.
Maybe now. We have the NASA CERES mission data showing that the greenhouse effect has remained constant since 2000 (see the greenhouse efficiency calculations by Willis). We also have Miskolczi 2023 analysis showing that atmospheric opacity (another measure of the total greenhouse effect) was constant from 1948 – 2008 using NOAA radiosonde data.
We don’t need models. No change in the overall strength of the greenhouse effect for the last 77 years tells us climate science has the basic physics wrong.
I’ve previously explained the physics for why this has happened multiple times. The data is not lying.
One thing that Willis has offered that sticks with me is the observation that despite large perturbations, much larger than the tiny increase in CO2 we have observed, the planet has somehow managed to remain within the remarkably narrow range of conditions suitable to maintain life.
“Maybe a thousand years from now?”
More like today, but your favorite LLM AI writing assistant won’t tell you that Charles.
“Demanding measured proof of how much warming is caused by CO₂ is a rhetorical dead end—not because it’s unreasonable to seek evidence, but because it betrays a misunderstanding of what’s empirically measurable in a planetary climate system. The question collapses under its own demand for impossible precision in a noisy, chaotic, and multifactorial system.”
It turns out this was not a stupid question to ask, however, it also turns out it is quite stupid to believe CO2 has caused any measurable warming, and even more stupid for someone to be telling skeptics not to question it. The case for CO2 warming evaporates under scrutiny.
The 12ma∆ World 2 meter temperature (T2m) follows the 12ma∆ SST by one month, and T2m is ~6°C colder than the World SST, proving the ocean warms the atmosphere.
The T2m trend is slightly greater than that of SST, resulting in a 0.018°C difference by 2024 that is within the range of uncertainty, if this difference is even physically real.
This difference, if not a result from uncertainty, would likely be a result of radiative forcing in the atmosphere by H20 and CO2. Water vapor has increased along with CO2, and it is a stronger GHG. This 0.018°C difference spread out over four+ decades since 1980 yields a possible atmospheric forcing of ~0.004°C/decade, mostly from H20.
Since water vapor has 2-3x the GHG forcing effect than carbon dioxide, it is safe to say the CO2 forcing is on the order of 0.001°C/decade, and for all practical purposes, is zero.
Furthermore, using the 12ma∆ on climate timeseries allows for direct comparisons with cross-correlation analysis, as shown below. The carbon dioxide anomaly 12ma∆ lags all the major climate indices listed, including T2m, which it significantly lags by 5 months.
It turns out it was stupid not to question this.
The sun warmed the oceans which then warmed the atmosphere. Nothing at all complicated is happening.
We even have the NASA CERES data to show us precisely how much additional solar energy has reached the surface since 2000. This may not be “proof” but it sure is strong evidence.
I’m not sure what Charles is looking for?
Actually, I find the claim that World T2m is less than SST a little surprising because of the large difference in Specific Heat between water, and terrestrial materials and air.
“It turns out this was not a stupid question to ask, however, it also turns out it is quite stupid to believe CO2 has caused any measurable warming, and even more stupid for someone to be telling skeptics not to question it.”
Thank you, Bob !!
We are told time and time again that CO2 causes warming…
The obvious questions are.. a) how much? and b) where is the evidence?
Yes but..you can also ask questions about what exactly that ‘radiative forcing’ entails.and so on…
One at a time, then –
Adding CO2 to air does not make it hotter.
“Radiative forcing” is exactly meaningless jargon
If you have any others, I can answer them for you.
Still no GHE.
It’s a good article, but it misses an important point of view.
From the point of view of a human, with a strong survival instinct, who has lived on plant Earth through all of the recent global warming (i.e. me), the plant-wide experiment has been completed.
The result? It got mildly warmer, mostly on very cold nights, and the planet got greener because the CO2 we emit is used by plants to make more biomass.
The science and the models are all very interesting, but the fact is the 100-year, planet-wide experiment is complete, and plant Earth is fine. Actually Earth is better off if we consider the health of the biosphere, and we should because we are inextricably linked to it.
If man had not come along to dig up and release CO2 that was/is trapped underground, plants would have had to evolve some other mechanism for getting the job done. But humans should be proud that we figured out how to do. Not only that but we figured out how, during the process of liberating more CO2, to remove chemicals that are actually hazardous to the biosphere
If the climate change of the next hundred years is the same as that of the last hundred years, we (and nearly life forms on Earth) will be even better off.
Also, we are now pretty certain that a large portion of the recent warming was due to a decrease in cloud cover, not to the warming effect of CO2. Therefore, decreasing CO2 emissions is likely to have a negative impact on the biosphere—it won’t reduce warming by much, but it will slow greening.
+100
This is the type of holistic analysis Freeman Dyson always advocated for. And it is the type of holistic analysis that climate science has ignored for at least 40 years.
The question should be Can you provide empirical measured proof of how much CO2 is caused by warming?”. This can be largely answered today using frequency-domain analysis and coherent averaging to minimize uncorrelated signals (i.e. changes in CO2 concentrations not related to temperature).
As shown in the phase response [CO2] lags temperature by six months over almost all periods except at frequencies of 0.75 and 1 yr^-1 (periods of 1.3 and 1 year respectively), where the delay is less than 2 months. The spike at 1 yr^-1 is the seasonal variation that is normally removed in time-domain analysis by applying a one-year moving average. I don’t know what the 1.3-year process is.
From the magnitude response we can observe that the [CO2] sensitivity is 4.9ppm/°C over 10-year periods (freq=0.1) and 2.8ppm/°C over 3.3-year periods (freq=0.3).
The answer is quite clear – Climate Models have been consistently wrong. From the text: “climate modelers layer their assumptions about radiative forcing, feedbacks, and cloud behavior to produce projections decades into the future—projections which have consistently overestimated warming in the short term”
Following the Scientific Method extrapolated to modelling, the hypothesis is that CO2 from anthropogenic fossil fuel combustion causes catastrophic global warming. The null hypothesis is that there is no catastrophic global warming. The statement in bold above demonstrates that the hypothesis is false. There is no catastrophic global warming demonstrated from climate modelling.
I believe Mr. was referring to the wording.
Correct.
Grammatical Pedantry hasn’t yet been included in the communicable diseases register, but with adequate donations to the research projects of certain NIH officials, it’s a sure thing.
Trouble is, so far Go Fund Me doesn’t see my need as a worthwhile enough cause. 🙁
My mistake, I’ll take my double negatives and hide under the bed.
🙂
I don’t see it as pedantry. The entire meaning of the sentence is different. Words matter.
There is no know scientific measurement of the future.
Since there is no known process to measure the future, what empirical evidence is there the future exists?
Bravo! And Amen.
“… it also reflects a misunderstanding of how climate science works. “
That is quite true. The misunderstanding is that climate science is science, whereas it is a religion of beliefs, prophesies, ex cathedra pronouncements, infallibility, apocalyptic predictions, confession of sins, atonement and penance… including plenary indulgences for the right amount of cash… the excommunication of heretics.
Ayup, sounds like religious tenet to me too, now that you put it that way.
and virgins. They need more virgins.
(strictly for immaculate conceptions of course)
I don’t think you got the two memos:
1: immaculate conception; and
2: virgin birth
Virgin birth? I thought everybody was born a virgin.
And above all- politics- for the redistribution of wealth.
Let us not confuse “climate science” with “Climate Science (TM)”.
Plant growth is a sensible metric. I believe that has gone up.
trees are growing faster- that’s been researched
My take is very different. Asking that question reveals the unsoundness of the entire proposition. Many of the reasons stated above against asking the question reveal glaring weaknesses in the science behind global warming.
The question at best highlights the fact that the alarmists are making a judgment call about something that can only be inferred. But it’s not an effective response to the fear-mongering propaganda. Once a person agrees that it’s uncertain, we’re still left with the prospect that there ‘might’ be a catastrophe. Most people are prudent enough to try to avoid foreseeable disasters. So there, you’ve lost the argument.
What is needed is to persuade that there’s overwhelming evidence that the effect is harmless if not beneficial, and that adaptation is feasible and far more practical than eliminating fossil fuels. Most people are prudent enough to avoid cures that are worse than the disease.
“Once a person agrees that it’s uncertain, we’re still left with the prospect that there ‘might’ be a catastrophe.”
Good point.
Or…there might not be a catastrophe…
I think you and the guys below missed Rich’s point.
He was talking about trying to convince a True Believer that the effects of CO2 are unknown, and says that even if he is successful in convincing this person of that, this still does not alleviate the persons fear that CO2 could somehow be dangerous.
So arguing that we don’t know a lot about how CO2 interacts with the atmosphere, is not a good argument against Human-caused Climate Change.
I can neither prove or disprove a possible climate catastrophe from burning fossil fuels. I can state confidently I see no evidence of it.
Tomorrow, a meteorite might fall from the sky and hit you in the head. Therefore, it is reasonable to pass a law requiring everyone to wear hard hats whenever they are outside.
It should probably be a steel helmet with Kevlar liner and Kevlar vest with ceramic insert. Last I heard there was a cow and one human (and I’m not sure about the human) killed by a meteorite. But then as Handgun Control Inc. used to say, “No price is too high to pay if it saves one life.” No one wants to go down in the history books as being the parent of a child killed by a meteorite.
The only person killed by a meteorite was inside her house napping on the couch, Ann Hodges, 34, was napping under quilts on her couch in Sylacauga, Alabama, on November 30, 1954, you’re not safe anywhere!
No, Ann Hodges wasn’t killed –
she divorced in 1964 & died 10 September 1972, Sylacauga, Alabama, United States of America in a nursing home from kidney failure. She was fifty-two years old.
https://facts.net/earth-and-life-science/34-facts-about-ann-hodges-meteorite/
https://theexasperatedhistorian.com/the-womens-list/774-ann-hodges/
https://www.spacecentre.co.uk/news/space-now-blog/the-woman-who-was-hit-by-a-space-rock-and-lived/
The only person recorded as killed by a meteorite was in Turkey in 1888 –
https://www.popularmechanics.com/science/a31248702/first-confirmed-meteorite-death/
This is what risk assessment is for. But to do a proper risk assessment you must be able to quantify the risks. Simply saying something is possible is *not* a quantification of risk. Saying “I don’t know” is a valid assessment, especially since *not* doing something yesterday has proven to get you to today. Doing something else can’t be proven to get you to tomorrow if you don’t know the risk.
But … Precautionary Principle. If it might happen, we need to prevent it. The probability of occurrence may be very low, but the consequences of occurrence are catastrophic.
The point being made sarcastically by MarkW is that the probability of a person being killed by a meteorite is so low that only an irrational person would worry about it.
Are you saying that 6″ of armour-plate on the roof is going a bit far ? 😉
Yes, anything more than 5″ is over the top!
Seriously, there was a recent doorbell camera of a small meteorite hitting the concrete walkway in (IIRC) Nova Scotia. The meteorite was shattered into a large number of small pieces, and there was only a small dimple left in the concrete. By small, I mean it looked smaller than the damage I think a .22 LR would do.
I better go back to wearing my tinfoil hat because aliens MIGHT be affecting my perception of reality!
I don’t know about you, Jim, but there are some commenters here that should probably be putting their tinfoil hats on even before they take their morning med’s.
There is a door right next to ‘precautionary principle’ called ‘ unintended consequences’..
It would be good if the people behind the doors talk to each other..
“It would be good if the people behind the doors talk to each other” It might be better if they didn’t talk to each other at all. Why waste perfectly good enjoyment time arguing?
If we could depend on nothing stupid and harmful being done unless a proper risk assessment shows it to be necessary, Tim, then we wouldn’t have already wasted trillions of dollars destroying western civilization.
Take another look at the caliber of intellect that inhabits Congresses and Parliaments.
“Suppose you were an idiot, and suppose you were a member of Congress; but I repeat myself.” — Mark Twain
Obviously, this isn’t a new problem.
Excellent!
“Asking that question reveals the unsoundness of the entire proposition.”
Thank you. !!
I think it was Andy May who has said several times, something like….
“Warming by atmospheric CO2 has never been observed or measured anywhere on this planet, or any other planet.”
But that is just an irrelevant statement. An IR camera can easily show you how much IR is absorbed when IR passes through CO2 and H2O vapor. The calculations that color the screen pixels are well accepted physics. Saying “never observed or measured” is like saying “it’s NEVER been proven that there is conservation of momentum when a bat strikes a baseball.” Nothing to do with accepting the principle of conservation of momentum.
Or/ and: is general ‘climate science’ actually science? Can hypotheses actually reliably turn into theories? I ask that because it seems to me that, wherever you’re coming from any theory about the climate and particularly temperature is in essense based on assumptions underpinning it. It usually presents a hierarchy that can be questioned. So, anyone how says ‘it is very simple’ and presents a set of equations i find problematic. Because what ALWAYS follows is: maybe, but…
‘The serious skeptical position doesn’t hinge on denying radiative physics, but on questioning how much warming will result, how models perform, how feedbacks behave, how reliable the temperature record is, and most critically—whether climate policies based on uncertain projections make any sense.’
I consider myself a serious skeptic. It starts off with the fact that there is no evidence in the geological record, whether from Eocene carbonates or Pleistocene ice cores, that CO2 is the control knob of the Earth’s climate ‘system’. This leads me not to ‘deny’ the radiative physics underpinning this narrative, but to question its specific application to the lower troposphere, where thermal radiation emitted by the surface and absorbed by IR active gases is predominantly converted to sensible heat by collisions with other gases within meters of the surface.
Need to add re. ‘how models perform’ – the simple response is they don’t. This arises from the fact that the radiative impacts of CO2 ‘forcings’ input into the models are demonstrably exceeded by uncertainties in the radiative effects of clouds, which are misspecified by the models, as evident from known errors in the extent of output cloud coverage.
That was my basic approach which led to the discovery we’ve reached a maximum greenhouse effect for CO2. This is why Willis E found no increase in “greenhouse efficiency” in the NASA CERES data.
The warming effect by radiative gases is real, it has simply reached the point where more of the gases will not cause additional warming.
“The warming effect by radiative gases is real”
No it’s not. Adding CO2 to air won’t make it any warmer.
A potential way to answer it’s contribution…in isolation but in the real world.
4 Cube solution
4 – Cubic Meter square cubes
1 sealed with ambient air (control)2 sealed with 300ppm CO23 sealed with 600ppm CO2 (1st doubling)4 sealed with 1200ppm CO2 (2nd doubling)Each with an internal temp sensor similar to an auto reporting weather station
Left outside in the open. Since CO2 is the only changing factor the warming capacity of the doubling of CO2 could then be determined.
The 300ppm box should be slightly cooler than the ambient control.
The 600ppm box should be measurably warmer by the amount of warming from doubling CO2
The 1200ppm box should be warmer by twice that amount
Doubling CO2 is the only changing factor
If you added a 5th cube with CO2 down at 180ppm it should measure cooler than the ambient control
I would thing this experiment would provide measured empirical evidence of CO2s potential in a real world setting (without feedback contributions)
There is nothing “real world” about sealed boxes.
Agreed. Such an experiment would eliminate the effects of convection, advection, clouds, and the influence of oceans, just to name a few things that matter.
Your comment seems to indicate your stance is no experiment can give us useful information because it was not done in the “real world”.
If I read you post wrong please explain further.
The objection is the proposed experiment is simple while the climate is complex. The climate is a set of enormous, complex systems that interact in ways we are nowhere close to understanding.
However it would give an empirical number to the potential contribution from CO2 without any other factors altering the outcome.
Not CO2 + H2O
Not CO2 +/- Clouds
Not CO2 +/- Advection/Convection
Just CO2
A real experiment tries hard to hold all factors except for the one you are measuring constant.
Since a sealed box, especially a small one, bears no relationship to the actual atmosphere, it violates this constraint.
How so? Wouldn’t a sealed box prevent additional water vapor from influencing the results?
As you stated it, why wouldn’t “a sealed box hold all (other) factors…constant” with the only change being CO2?
Sealed implies that no other factors would change.
The intent isn’t to mimic the “Real World” the Intent is to determine the contribution, if any, from CO2 and to ascertain the potential contribution from it’s doubling
Unless you can insulate your boxes, the air temperature will always be the same as the ambient air temperature for all 3 of your boxes.
Insulation could be achieved by double walled construction with either a vacuum or a thermally inert gas between the layers
However the intent is to monitor the potential temperature change with CO2 being the Only Variable
If CO2 can affect temperature then the 1200ppm box should be warmer regardless
John Tyndall’s experiments showed that increasing the amount of CO2 in air resulted in a reduction of radiation reaching his thermopile, and a consequent indication that the temperature fell.
Purging air of CO2, and repeating the experiment, results in temperature rise.
Completely contrary to any GHE supporters who claims that adding CO2 to air makes surface temperatures hotter!
Nobody has managed to contradict Tyndall’s results. I doubt that anyone who accepts reality, and has observed their surroundings, would bother wasting their time trying.
No GHE.
The energy incident on his thermopile fell. Therefore the energy was absorbed by the C02. So its temperature had to increase but his apparatus could not measure the tube temperature accurately enough due to natural convection from the surface. Your assumption of what you think Tyndall showed is bogus.
His apparatus could detect changes of 0.00002 C. Surprised?
But anyway, the CO2 was heated, as you say, but that is irrelevant. The thermopile received less energy and cooled. Similar to the atmosphere blocking the Sun’s radiation, resulting in lower maxima,
Now I suppose you are going to claim that the CO2 in Tyndall’s experiment made the thermopile hotter by reducing the radiation falling on it!
Much like deluded GHE believers think that blocking sunlight with GHGs results in a hotter surface!
Tyndall showed what he showed. You even stated that CO2 absorbing energy results in lower temperatures! No wonder ChatGPT spews out so much misinformation – it gets it from people like you, who have no clue.
Come on, tell me how adding CO2 to air makes it hotter – laughter is good for the soul.
If this were the case then wouldn’t uninsulated greenhouses also get no warmer than ambient air temperatures?
The intent is not to measure the temperature difference between ambient and boxed measurements but to measure the difference between individual boxes.
Give It a try. Use a temperature controlled environment – a freezer room, or a pottery kiln, if you prefer a bit of extra heat.
After a little while, all your cubes, gas, and thermometers will be at precisely the same temperature as the environment which contains them.
That’s my guess, but feel free to perform your experiment and show that I’m wrong. Or you could just carefully pop a thermometer into a jam jar of CO2 (the CO2 will sit there quietly for long enough), and see if it gets hotter. I say not. Let me know what you find, if you like.
Q) If I did, and posted my results here, would you believe them?
You’d be better doing the experiment yourself then you’d be more likely to believe the results.
Yes. If you showed that replacing air with CO2 caused a rise in thermometer temperature with no change in the environment, I would indeed see if I could reproduce your results.
But you have no intention of trying to demonstrate an impossibility, have you? I don’t blame you for not wanting to look foolish.
That is one smart article, and regrettably more of an exception. Given all my knowledge, I can tell you “climate change” would be over, if people just properly learned about climate physics. Because then they could start discussing the issues there are with it, and there are many.
The problem I have is, despite having identified the key blunders in “climate science”, I can not even communicate them. I can not tell someone what is wrong with “consensus science” just because people have no clue what “consensus science” is about. It is a bit like Groundhog Day. Everytime I try to tell what is wrong, I am thrown back to having to explain climate physics first, which people reject, because they reject the whole narrative. Then telling them they do not know, or have not learned it properly, will inevitably be considered an insult, and so on..
CO2 forcing:
“Consensus science” claims CO2 forcing was the sum of “fluxes” at the tropopause, that is the decrease in upwelling- and the increase in downwelling radiation there. If you add up these “fluxes” up you ~3.7W/m2 for 2xCO2. This is opposed to a mere 2W/m2 reduction in OLR, including clouds btw. Without clouds it would be 3W/m2, the figure Wijngaarden, Happer name.
This “logic” is highly questionable. For one climate scientists themselves are not really aware of it. Schmidt et al 2010 for instance names the given CO2 forcing simply as the delta OLR. Of course given, or “natural” CO2 forcing can not work different than anthropogenic CO2 forcing. Also this provides many more issues downstream. And of course we get this absurd “hockey stick”:
https://greenhousedefect.com/unboxing-the-black-box
WV Feedback:
WV is vastly overstated as a GHG, and circumstantially is no GHG at all. One problem is surface emissions are equally overstated. The emissivity of water is ~0.91, at 288K it will emit 355W/m2, not 390. Overall the surface will emit ~360W/m2. This shoves off some 35W/m2 from the GHE, which is only about 120W/m2 in magnitude. The logic is that radiation emitted by the surface, not going out OLR, must have been attenuated by the WV continuum. In reality that radiation was not emitted in the first place.
On the other side, something people tend to ignore, WV strongly reduces the lapse rate, thereby shrinking the GHE all over. Thx to WV it is ~6.5K/km, without it would be ~10.8K/km. WV exerts this cooling on ALL GH-agents, not just itself. And if you add up the numbers, the net effect of WV is actually cooling.
Also in modtran, ignoring the (negative) lapse rate effect, there is no way to get a 1.8W/m2 in WV feedback. It is well below 1W/m2, regardless of what you try. That is roughly on par with the negative lapse rate effect.
Why “climate science” yet thinks WV was a strong positive feedback, is due to the observed dOLR/dTs relation. It undercuts the expected “Planck Feedback” by ~1.3W/m2. If you assume negative lapse rate effect of -0.5W/m2 and add these up, you get 1.8W/m2. The chart illustrates the logic..
The blunder here is this: they never checked if the lapse rate would actually behave, over the observed variations of Ts, like they assumed. These variations are by latitude, seasonal (Ts warms and cools in an annual cycle), or interannual (like El Ninos/La Ninas) btw. What actually happens is the opposite. The variation in Ts is predominantly a thing of the surface, not so much the atmosphere. The lapse rate does the opposite, which already explains why dOLR/dTs undercuts the “Planck Feedback”. The whole approach is pointless, WV feedback actually negative.
If you understand this, we can all go home, because “climate change” then is over. Or we keep on doing many years of Groundhog Day.
https://greenhousedefect.com/the-holy-grail-of-ecs/the-incredibly-stupid-case-of-water-vapor-feedback
Well done…!
As shown here EBRE versus models.
In addition, the 15um single spectrum 0.08eV is weaker than any colour in a rainbow. Hardly a climate driver.
“Building consensus is a politico-religious concept, not a scientific one. Consensus involves creating broad agreement amongst a group of people, but science should never lean on agreement to provide a false sense of comfort. When forming their worldviews, scientists must emphasize the evidence, not the opinions of their fellow scientists.
Some of history’s most important scientists fought against the “scientific consensus” to make their mark.” The Stanford Review
But you can take the other approach and falsify the claim of the UNIPCC, that CO2 dominates global climate, which means temperature to most people.
Use the natural record of the whole system as we measure it to be, no models required, to test that claim .
That shows there is NO such dominant effect, from multiple records, from both the recent Holocene and prior interglacial periods. Much more warming, much Less CO2. No dominat control of Earth climate by CO2. QED. Your witness…..
Simples.
As described by the lovely Brian, here:
The other important thing about your graphic is that if you extend the CO2 to the current nearly 425ppm the Temperature side would adjust to an anomaly of +16°K at the same scale. Since were at 421ppm and the temperature anomaly isn’t >+15K the apparent correlated relationship falls apart at higher concentrations
The whole discussion of warming or cooling courtesy of CO2 is just so much noise. The only source of oxygen in the world is plant life whether it is on land are in the ocean. The only source of food for the plants is CO2 and sunlight. Take either one of these two away and the earth becomes a lifeless wet rock. We can’t live without oxygen and plants can not live without CO2.
Also, there is the assumption that a slight warming is a problem. So, much of the fight by skeptics should be showing that such a slight warming isn’t a problem and for much of the world it’s a benefit.
👆
💯
Absolutely.
Yes, we’ve now had what? – 2 full 30-year climate cycles since the questions of human activities and emissions on climate behaviors have been in play, and we’ve seen bugger-all negative impacts, let alone any “crisis”.
(a qualification – $trillions wasted on climate prognostications is certainly a “negative impact”)
2021 UN IPCC Sixth Assessment Report, The Scientific Basis, Working Group I (WGI), Chapter 12, Figure 12.12. There is no increasing extreme weather events on a slightly warmed Earth.
Just keep pointing that out when your governments and media lie to you. Your governments constantly lie to you about matters great and small.
No. Much of the fight by skeptics should be showing claims of human warming are nothing more than speculative navel gazing and not science.
I appreciate this article for understanding the author’s thinking. I too have opinions about the most effective and scientifically sound points to make in the “climate” debate. About “empirical proof” it suffices to say that the claimed static radiative effect of incremental CO2 cannot be isolated for reliable attribution of a measured warming trend or of any trend of any metric of climate interest, as a result.
The reasons are physical. For the longwave radiation fans, the NOAA visualizations of the observed Band 16 radiance values from the GOES East and West satellites are helpful to see the attribution problem. And for fans of the atmosphere as the compressible working fluid of its own circulation, the concept of energy conversion, as in the direct computation of the “vertical integral of energy conversion” within the ERA5 reanalysis model, help to show why expecting detectable “warming” to result from incremental CO2 was a misconception all along.
WUWT is to be commended for allowing differing viewpoints to be offered for consideration and critique. So thank you for that.
In a reply I am going to paste a link to my comment on the March 9th post by Andy May, “Beyond CO2…” for further explanation.
And here is a link to a Youtube channel where I have posted short time-lapse videos to get the essential points across. Each video as a “readme” description for a full explanation.
https://www.youtube.com/channel/UCI8vhRIT-3uaLhuaIZq2FuQ
One more thing. Once a climate skeptic accepts the “forcing” + “feedback” framing of the question of the climate system response to incremental CO2, there will be a confusing debate about models, measurements, tipping points, impacts, etc. It is unnecessary in my view. Look instead at how the emitter works, and how the dynamics overwhelms any tendency toward a sensible heat gain result – most certainly to rule out “warming” to any harmful extent.
For further discussion:
https://wattsupwiththat.com/2025/03/09/beyond-co%e2%82%82-unraveling-the-roles-of-energy-water-vapor-and-convection-in-earths-atmosphere/#comment-4046805
The CliSciFi modeled water vapor feedback in the troposphere is missing. There are no measured “Hot Spots” in the troposphere according to radiosonde and satellite measurements.
And no trend in Arctic sea ice extent since 2007, and no problem on the Greenland ice sheet accumulating mass consistent with the 1981-2010 base period, etc. etc. All of which help demonstrate that the properly framed null hypothesis – that incremental CO2 has no detectable effect on the climate system – has not been falsified.
Temperature proxies have limited value. Especially if mann-ipulated. 🙂
I got the impression that the author was talking about the long term thermometer based measurements here.
All of your bullet points are excellent and should be asked- and they have been asked but the alarmists won’t respond.
You forgot the fourth monkey…the one flipping the bird and basically telling skeptics to f**k off.
The post was great as far as it goes, but the big problem–the elephant in the room–is that you can’t have a rational conversation with irrational people or people with a Messiah complex who can justify anything because they’re trying to save the world. You can’t fight moral superiority with logic.
….. that’s what I was thinking, even the more cowering ones who daren’t say they know it’s a crock and start talking about glaciers (like they’re a fabulous proxy for global temperatures, not to mention dead polar bears whose corpses can’t be found). It’s important to note that these people have a vote, and look at what the UK now has and what the US almost had with these kinds of people voting phony-left.
True, here in Wokeachusetts hardly a score of people dare to resist the climate cult. They don’t even bother to tell you to shut up- they just pretend you don’t exist. The climate cult here seems to be unaware of President Trump and his desire to end that cult. I’m sure they’ll find out soon. 🙂
The question, as it is structured asks for too much. When someone claims CO2 is warming the planet, simply ask them ‘how much?’.
It’s not seeking a definitive answer, it merely demonstrates that a definite attribution is not possible and making a firm claim without the ability to quantify ‘how much’ is specious. According to Lindzen and Happer, the answer is: “Not much.”
That has already been answered by the IPCC….. ”All of the warming since the start of the industrial revolution”.
The answer to that should by…prove it or piss off and stop wasting everyone’s time and money – your choice.
That implies that there has been no natural warming. Does anyone believe that?
No it doesn’t.
From the article: “Even the IPCC doesn’t claim that the warming due to CO₂ can be directly measured. Instead, they use “attribution studies” based on model simulations. For instance, they simulate Earth’s climate with anthropogenic CO₂ and without it, and then compare the model runs to observed temperatures.
The result is a claim like “most of the observed warming since 1950 is very likely due to human activity””
Well, the IPCC can’t be correct, that doesn’t even take into account the previous, similar warming that took place during the Early Twentieth Century, and even the IPCC doesn’t attribute that warming “mostly” to CO2. They claim CO2 had little effect back then.
So we have two similar warming periods, and the IPCC says the earlier one is not mainly caused by CO2, and the latter one *is* mainly caused by CO2.
This is not logical.
The only people who think this makes sense have visions of Hockey Stick charts in their heads.
“This is not logical.”
Excellent point. The use of climate models to support attribution of ANY amount of warming to rising CO2 has been utterly circular all along. Not everyone appreciates this point about the reasoning, but it has to be said.
It’s nothing but unsupported opinion dressed up with a little sciency-sounding language. Some might call it scientism.
I challenged a warmist on this point. His response was that even though we have no idea what caused the pre-1950 warming, whatever it was stopped and was replaced by CO2.
Q: How do we know that?
A: The models have proven it.
It’s religion all the way down.
From the article: “The serious skeptical position doesn’t hinge on denying radiative physics, but on questioning how much warming will result”
I agree.
So how much warming will result from 420ppm in the Earth’s atmosphere?
The answer is: Nobody knows. The IPCC doesn’t know. There are a lot of estimates out there from benign to scary. But nobody knows for sure. I like Dr. Happer’s work.
Even Dr. Happer’s work assumes a constant vertical relative humidity. This is not supported by NOAA data.
“So how much warming will result from 420ppm in the Earth’s atmosphere?”
Not quite the right question..
try
“So how much warming will result from going from, says, 300ppm to 420ppm in the Earth’s atmosphere?
The answer to both questions –
None.
To any Newbies out there….Michael is stubborn but wrong on this point…look at Happer for better analyses….
“Michael is stubborn but wrong on this point…look at Happer for better analyses….”
I agree with Feynman who said “It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.”
Happer has not done such an experiment. His analysis is worthless, unless experimental results support it – and there is no such support.
“For those chafing at the word “modeling“, it is through modeling that we convert satellite measurements of brightness into global temperatures. i.e. UAH 6.1.”
Respectfully, the satellite measurements of brightness do not fully account for the path loss that so-called “brightness” incurs at every sampling point due to various factors such as water vapor, dust, etc. When you average all these uncertain “brightness” measurements you wind up the an uncertainty interval larger than the difference trying to be determined. In other words, the correct answer is WE DON’T ACTUALLY KNOW WHAT IS HAPPENING.
It’s all based on foggy crystal balls being read by climate “psychics”.
Indeed.
Also, the modeled UAH using satellites is an estimation of the temperature of the lower troposphere. There are people who think they are accurate. But, as it is modeled it should be offset by actual reliable temperature measurements at surface level without the noise ie UHI effect using only high quality stations.
And THAT is not happening.
There is an interesting new video released on Tom Nelson’s podcast about this very thing.
https://m.youtube.com/watch?v=_i6Y0rrOqXw
Its what you get when subtracting one large number from another large number and getting an answer smaller than the uncertainties inherent in the development of the large numbers: Quackery.
+100
Processing empirical data is not the same thing as modeling future results. The point of climate modeling is projecting a trend into the future based on assumed factors, mainly climate sensitivity to CO2, and hypothesized feedback factors.
So, we may have an idea of what is happening recently, but we certainly don’t know what will happen in a decade.
“Skepticism can be scientifically rigorous, effective, and intellectually honest”
Yes, It can be used to prove that CO2 actually has NO climatic effect, apart from decreasing Earth’s albedo because of its greening of our planet..
See “Scientific proof that CO2 does NOT cause global warming”
https://wjarr.com/sites/default/files/WJARR-2024-0884.pdf
Because of Acid Rain and health concerns, legislation was passed in the US and Europe in the 1970’s to reduce the amount of industrial SO2 aerosol pollution in our troposphere.
Its amount in our atmosphere, as tracked by the Community Emissions Data System (CEDS) of the Pacific Northwest National Laboratories, peaked at 141 million tons in 1979, and 1n 1980, temperatures began rising, as the amount of pollution in our atmosphere began to decrease.. Decreasing levels of atmospheric aerosol pollution increases the intensity of the solar radiation striking the Earth’s surface, naturally causing warming..
By 2022, SO2 aerosol .levels had fallen to 73 million tons, a decrease of 68 million tons, and temperatures had risen to 0.8 Deg. C. However, this inevitable warming due to decreased levels of atmospheric aerosol pollution has instead been WRONGLY attributed to rising levels of CO2 in the atmosphere.
Because of this wrong attribution, the Western nations and Australia/NZ are destroying their economies!.
The obvious solution to our rising temperatures, unfortunately, is to increase the amount of SO2 aerosols in our atmosphere.
The 11 year solar luminosity variation changes downwelling radiation by about as much as 15 years of CO2 emissions (~0.3 W/m2). By looking at the earth’s energy imbalance, we can see the effect on warming; running a fourier transform on the data allows us to see cyclic signals fairly easily, even when they are quite small. The IPCC says the warming is amplified by a factor of ~3, but the analysis shows the warming effect of 15 years of CO2 is much less than one; there is no 11 year cycle in the EEI. The effect of CO2 is strongly suppressed, according to the data.
Any effect that raises the surface temperature causes more IR to leave for outerspace, more evaporation, more convection, more clouds to reflect incoming sunlight….
one only needs to look at and think about an energy balance Trenberth type diagram to see that CO2 forcing of 3 watts per doubling is nearly irrelevant in the whole scheme of things. So it is being used as a power aphrodisiac similar to religious fervor of half a millennia ago….a wee bit of feel good butter on a wealth grabber pancake…
“Any effect that raises the surface temperature causes more IR to leave for outerspace . , .” – resulting in cooling.
It doesn’t matter – the Earth loses energy at a rate of about 44TW. It’s cooling.
Here’s ChatGPT –
“Where Are We Now?
In Conclusion:
Thank you for your patience, and I hope this clears up the misunderstanding! The Earth is indeed cooling, and there is no equilibrium temperature at the moment because of the ongoing energy loss.”
Took me several questions to plow through the massive amounts of misinformation spewed out by ChatGPT, but I got there in the end.
I think your question would be of interest here.
Very odd, it tells you how much the Earth is warming if you ask about Global warming. Seems to be a “consensus finding” search engine that uses your phrases as a search key.
Should be useful if you have no idea what the consensus is. But if you believe convenience store robberies are the work of Satanic cults, you might get corroboration of that too with the right questions.
“Very odd, it tells you how much the Earth is warming if you ask about Global warming.”
Not really. The fact that a near surface thermometer shows an increase in temperature tells you that the thermometer is hotter. It bears no relationship to the fact that the Earth is cooling.
“Climate scientists” use all sorts of misinformation – “surface”, “global climate”, “energy balance”, and all sorts of other mutilations of the English language.
All this in an effort to apparently draw people into the GHE cult – the GHE which is so mysterious that it has no consistent unambiguous description.
People who are disinclined to believe in something that cannot be described have been ostracised, lost employment, been threatened with imprisonment or even death – shades of Torquemada and the Spanish Inquisition!
No GHE. Adding CO2 to the atmosphere doesn’t make it hotter.
“It is inferred through modeling and statistical attribution studies.”
Video games. We are letting a bunch of guys playing minecraft run the world.
Nice post. Answer is clearly no. Not only is it not possible to provide empirical measurable proof of how much warming is caused by CO2, we also cannot predict how much earth (and local) temperatures will be twenty years from now… So the only answer is to wing it and make unsupportable claims. Climate and local temperature estimation is a complex system .. and to claim that we can is a legitimate question to ask.
“So the only answer is to wing it and make unsupportable claims.”
If anyone makes the claim “CO2 causes warming”, then they should be able to show “how much”, and provide measured scientific evidence to back it up.
If they can’t, they should withdraw the claim.
Hear, hear!
Buy an IR camera and read up on how it works and how that explains what you can see on the LCD screen. The absorption of photons by CO2 and H2O on the way to the CCD are matters of extensive scientific work.
“If they can’t they should withdraw the claim”…They CAN so they aren’t going to withdraw the claim, nor will they bother to waste their time arguing the point with people who insist on proof of basic concepts.
You can make a good argument that the CO2 molecules that absorbed the IR on the way to your camera CCD just weren’t sufficient to show any warming, “similar to what one could expect of the climate system”. Suddenly you have something people can ponder, discuss, and come to reasonable conclusions about….and might even conclude your argument has intelligent merit….
“Buy an IR camera and read up on how it works and how that explains what you can see on the LCD screen.” Usual pointless demand by some delusional GHE cultist.
All matter above absolute zero emits photons, at frequencies dependent on temperature. All matter absorbs photons from hotter matter.
If you are trying to imply that adding CO2 to air makes it hotter, why not just say so? I can have a good laugh at your expense, and you can continue being delusional.
Here is what I usually ask. If CO2 causes warming, and CO2 is well mixed, then how can there be places that show no warming?
Perhaps because temperature is not climate?
“Perhaps because temperature is not climate?”
Nice meaningless word salad.
Good article, Charles.
The trouble with “Climate Science” is that the current crop of Climate Scientists is not studying climate at all. They are fascinated with thermometer readings. And not even thermometer readings themselves, but with averages of thermometer readings, which really have nothing to do with “climate”. If you wanted to describe the climate of an area to someone who was unfamiliar with it, you would certainly start out with the temperature variations, both daily and seasonally. Then you’d add information about seasonal variations in humidity, precipitation, cloudiness, wind direction and strength and maybe a few other local factors, none of which are represented by average thermometer readings, and all of which are descriptive of energy transport and its effects. This makes sense, because the local climate is determined by how the sun’s energy, which is most intense for about six hours a day (meaning on a circle centered between the Tropics and about 45 degrees latitude in radius) is distributed to the rest of the Earth over time. As the Earth turns, this energy is transported by several processes, one of the least of which is temperature-gradient conduction.
If Climate Scientists were really interested in studying changes to local climate, they would be focused on the water cycle, the major processes of which (evaporation and condensation) are isothermal. One day’s precipitation weighs nearly as much as the entire CO2 content of the atmosphere, (10^12 metric tons) and transports two or three orders of magnitude more energy than a several degree change in CO2 temperature would accumulate in a century.
And not even that, but averages of averages of thermometer readings.
Exactly.
Assessments of climates should be focused on basic real-world questions and answers such as –
“can I grow tomatoes around here, when should I plant them, how long before they’re ready to pick?”
And of course –
show your work.
They should be more concerned about the heat index than raw temperatures. And, they should be focusing on how the various climate zones are changing, rather than trying to understand what is happening from a single number — GMST.
Surely the carbon dioxide theory of global warming has failed, and failed in the way that Professor Stephen Hawking said:
“Any physical theory is always provisional, in the sense that it is only a hypothesis: you can never prove it. No matter how many times the results of experiments agree with some theory, you can never be sure that the next time the result will not contradict the theory. On the other hand you can disprove a theory by finding even a single observation that disagrees with the predictions of the theory.”
There have been many failed predictions of climate doom – and WUWT lists a whole load of them – any one of which should be enough to cast doubt on the whole theory – and yet millions still fear the carbon dioxide molecule.
There is no climate emergency.
And i would include the modeled UAH estimates in that.
Altipueri;
I agree, There is no climate emergency due to rising levels of CO2.
However, we ARE on the verge of a climate emergency due to the actual cause of our modern warming, which is the decease in the amount of SO2 aerosol pollution in our atmosphere due to Net Zero and Clean Air efforts.
,