Is the CO2 greenhouse effect saturated?

I’ve been on the look-out for the best arguments why CO2 is NOT causing climate change. Here’s the best one I’ve found to date along with some counter-arguments and evidence. It looks at whether CO2 is saturated in the atmosphere and more CO2 will now make minimal additional impact on warming. We get into the science at a molecular level on this one!

The Mallen Baker Show is aimed at all people who see themselves as change makers, with commentary on issues and change movements with a particular focus on climate change and environment, social issues, free speech and corporate social responsibility.

UPDATE: Added reference to paper by Zhong & Haigh 2013' which covers the saturation topic directly

References

1:56 Graph showing CO2 ‘saturation’ effect

2:12 Graph showing logarithmic nature of CO2 impact

2:36 Diagram of greenhouse effect

3:14 Composition of the atmosphere

6:36 Article by Professor Ray Pierrehumbert

11:27 Paper on CO2 frequencies in energy radiated back to earth

12:02 Spectral signatures of climate change in the Earth’s infrared spectrum between 1970 and 2006 in the upper atmosphere

12:02 And similar from 2016

Additional reading

Early paper (Kaplan 1952) showing CO2 effects in the upper atmosphere

Useful history of the development of climate science, which gives good detail on the piecing together of the evidence

The greenhouse effect and carbon dioxide, Zhong & Haigh, 2013

[MallenBaker]

My rules for comments in this forum.
 
You can post your opinion freely in the comments to any of my videos. I like to engage with people on arguments and issues. I will, time permitting, happily engage with comments that are polite and broadly on topic for the video in question. You can still post what you want but if you want a response from me, those are the criteria. If you want to preface your biting critique with an observation of what a total idiot I am, knock yourself out, but I won't respond to those comments any more than I would if someone said that stuff in real life.
 
Out and out obscenities and personal abuse will be removed. People who engage in bullying  other commenters will be asked to stop if I think they are making commenting here unpleasant for others. If they refuse to stop then they'll be removed from the channel.

[longbowarcher]

Here are some scientific facts that clearly show that an increase in CO2 does not lead to any significant increase in temperature



The co2 concentration today is 400ppm. The temperature is circa 18c.

in the Jurassic period the co2 concentration was 2000ppm, [5 times greater than today] the temperature was 22c.

in the Triassic period the co2 concentration was 2500ppm [ 6 times greater than today] the temperature was 22c.

in the Ordovician period the co2 concentration was 3000ppm [7.5 times greater than today] the temperature was 17c

in the Cambrian period the co2 concentration was 6000ppm [15 times greater than today] the temperature was 22c



For most of the time the planet was thriving not frying, the data shows that temperature is independent of co2 concentration

Look at the data for the Cambrian. The co2 concentration is 15 times what it is today but the temperatures is about the same as it is today. Look at the Ordovician, the CO2 concentration was 7.5 greater than it is today and yet the temperature was 2 degrees lower than it is today.

[ManScoutsofAmerica]

Someone a lot smarter than me, once told me, “if you can’t argue for the other side, you have no business arguing for your side”. He was right.

[Deliquescentinsight]

The adjustment of the graphs to swap the presentation of C02 'after' a temperature spike is interesting - they have tried to show C02 as a causation of temperature, when in fact it is a consequence of the oceans releasing more C02 when the temperature rises. Water Vapor has much more significance for climate than C02 . The so-called global warming trend halted, and so 'climate change' became the label. Sea ice in the arctic is fine. Antarctic also fine. Variations of climate patterns have always been with us, . Why do they keep cherry picking the start dates for the graphs, present the entire centuries, from 1900 - 2020! The 1930's were the hottest period in the past 2 centuries, vastly warmer than today. We can exchange opinions as much as we like, but the political dimension of this matter is very interesting to observe. Who are those who present science as being 'settled' and therefore beyond question? True science is never 'settled', the scientific method has nothing to do with 'consensus', it is about testing ideas, and reviewing results, not 'beliefs'.

[Ferreolus]

Dear Mr. Baker:

Absolutely fantastic explanation and your approach in all your work I have seen to scientific knowledge and inquiry is refreshing to the point of being painful.

I quite understand your explanation (physical chemistry having been my course of study at the University.) I confess I had not given much thought to the "CO2 saturation theory" but I do remember from my days of running IR on samples containing the CO group (slightly different absorption band but like CO2 quite intense) that the precise frequencies were very high absorption at low concentrations but that the intensity of rotational bands was quite low a low concentrations, whereas with increases in concentration there would be an apparent effect of the band broadening. Looking at the graph you presented I am not sure that these effects are not always apparent in samples of CO2 in rarefied atmosphere so that an increase of 300 to 400 ppm might not exhibit the same sorts of effects even assuming there were no other differences resulting from the CO2 being in a gaseous state (and having two conjugated C double bonds instead of the one) but it suggests to me that the matter is unlikely to be simple.

In any case, your explanation that increasing concentrations in the lower atmosphere slowly causes corresponding increases in concentration further and further up from the surface making the statistical probability of "escape" of IR radiation lower at a given level in the atmosphere where concentration is "not" yet saturated and the elevation at which such escape is efficient (for our purposes) further and further from the surface regardless of any saturation on the surface, very persuasive.

I will do whatever I can to share and encourage viewing of your excellent, commendably rational and helpful explanations to as wide an audience as possible. If only more people were able to discus matters with such articulate impartiality and dedication to the principles of science, we would be much closer to effective solutions. You neither sugar coat nor encourage people to panic. And that is important in a world where the speeches of the preceding President of the United States and, as I am a bit nonplussed and increasingly disappointed to discover, his successor each in their own way express themselves far too much with angry partisan hyperbole, fiction, prevarication and exaggeration.

Your videos are making the rounds not a moment too soon.

Best Regards

Grady Loy
Tokyo, Japan

[cvb]

I appreciate you going after the good arguments (and you chose one)and also your arguments against it. I am probably not scientifically capable of evaluating your argument but philosophically I recognize that it is at least logical. But there was something about your initial dismissal of the "nonsense" arguments, that CO2 is plant food and "do the math" that did not quite sit right with me. The latter is an argument and not a very good one, a little bit of fentanyl obviously does a lot of damage. Still, there is a valid point in it. The global warming people do have to show how such a small trace gas in the atmosphere can create global warming, but this they have already addressed, even if it is not super clear how much of the 1 degree C warming since the latter half of the 1800s is due to CO2 and how much is due to other bigger factors. But the plant food comment was not an argument but a statement, and obviously 100% true. If "deniers" use it to prove there is no CO2 caused global warming, then it is a bad argument. But it is usually used to deal with the emotive side of the issue. People hear about CO2 and picture coal factories and the smog in China, and emotively it feels like a poison to them. So the point of saying CO2 is plant food is not to argue that it therefore cannot be causing global warming, the point is to change the emotion around the issue so that you can get to the real science, as you have done in addressing the logarithmic issue in your video. It is only nonsense if it is billed as being an argument that CO2 cannot cause global warming because it is plant food, but I know of no one who makes that point. They are simply saying let us not think of CO2 as a deadly gas but as the food of life. Yes, too much of any good thing can be bad, but if it is a good thing then the question of what is the optimum level of CO2 in the atmosphere is still a relevant question, and as far as I know this questioned has never been answered.

[stoppernz]

1:27 No plant has drown in co2, they grow faster and tolerate drier conditions. This is no analogous to drowning things in water, that's a logical fallacy, appeal to the extreme.

[saunders]

I have really enjoyed all the stuff you post, and you are to be commended for all the time and effort you put in.

I don't share your faith in climate scientists not being part of groupthink/ conspiracies. My reading of the Climategate files was that the people at the top of climate science were ganging up on editors and peer reviewers to obstruct the promulgation of views they disliked. This is hardly the action of proper scientists, confident in the integrity of their own work.
When you throw in the actions of the media, who love to scare the bejasus out of everyone whenever something vaguely science based happens (Millennium bug, SARS, Coronavirus, CJD), you can see why people get excited easily.

As far as grants and kudos are concerned, climate science will always follow the money, and there is not a penny to be made if it is shown that warming is natural and we can do nothing about it.

It seems to me that many scientists have forgotten the corollary of Occam's Razor- warming has happened before and it could be happening again, and for the same reason.

Keep up the good work!

[miyu]

Missed the point on CO2 being plant food. The more CO2 is available the more a given plant will actually absorb. That is why greenhouses pump CO2 in to facilitate a better growth ratio. So. You completely missed it. Try again.

[tonystern]

No mention of other factors that can cause warming - sun spots, angle of rotation of the earth (precession). Why did the Roman and Medieval Warm Periods happen with low CO2 levels? There was no increased volcanic CO2 emissions at the time.

[element]

Some strong counter-arguments against C02 being the driving culprit for climate change in last 150 years:

1. A significant portion of the modern recorded global warming was PRIOR to the global large-scale industrial output of C02. There is a major discordance between anthropogenic C02 emissions and the global temperature record during this period (1880-1940).

2. The Atlantic and Pacific Multi-decade oscillations map quite well onto the global temperature record since the 19th century, this phenomena provides a strong candidate explanation for driving global temperature trends.

3. The global temperature rate of increase has slowed since 2000, despite C02 emissions massively accelerating by China and India. In other words, there's another significant discordance between the rapidly accelerating C02 emissions and the measured global temperature rate - they are not in proportion.

4. Atmospheric C02 increases are historically known to LAG behind the increases in climate warming. The explanation is that C02 is the resulting by-product gas of increased biome matter in a warm period, globally, which then decays more fully in warming periods, and importantly, in ecologies which were previously both less vegetated and too cool for thorough decay processes to take place.

[BlueShadow]

Commendably excellent and objective presentation.
Thank you for this.

Now, I appreciate your scientific consideration of both sides of the argument and, although I often find myself slipping into the tribal mindset (skeptical on mmcc), I like to think I do - at times, just as now having been settled down by your video - adopt a critical thinking mindset.

I have listened to both sides of the science through reading, watching debates and videos etc., and I do feel the skeptics' viewpoints to be more rational, acceptable and convincing... it makes more sense to me than what seems to be a scaremongering attitude generally presented by the proponents of mmcc. If this makes me - after what I believe to be objective critical appraisal - tribal, then I can't help that. If one believes/leans more towards a 'side' in anything, one can be accused of 'tribalism'.

However, putting the science aside, I believe there's another very important factor in this whole issue, and that is... history. Just look at the history of the global warming/climate change argument and the constant doomsday threats that the world will end due to mmcc/gw in 'x' number of years... and no such event has ever come to pass. Historical-pattern observation can often prove more soundly predicting than warring scientific opinions.

The problem is - applying the indisputable historical timeline - the issue has become not so much one of science, but one of a political infiltration.
This is the big problem, and why science seems to have been pushed aside in favour of the corollary tribalism.

AN HISTORICAL SYNOPSIS (and this is only touching the surface):

• In 1922 the NYT carried an article saying that within 10 years, there will be no more ice caps, seals are dying off and great shoals of fish were depleting at an exponential rate. It went on to state also that within a few years the Earth’s coastal cities will be fully submerged.

• In the 1970s, the great acid rain scare.

• in the 1970s/‘80s, as a youngster I remember news reports (you can still find them on YouTube) stating that with global cooling, we’re now about to move into a *new ice age*. They even proposed covering the polar ice caps with black soot in order to *stimulate* melting so as to prevent *global cooling* .

• in the 1990s/2000s, the issue of global warming was put forward and the scare-mongering recommenced with, additionally, the idea of a hole in the ozone layer ready to destroy us all!

• Then, according to Al Gore, the world’s coastal cities should be submerged by now (actually projected for 5 years ago), and the polar caps completely gone. [Very interesting how real-estate agents are still selling multi-million dollar coastal residences in Florida and elsewhere. Obama, for example, hasn’t sold his coastal estate and scurried off in blind panic].

• With global warming having become static for 25 years, they decided to change the description from ‘global warming’ to ‘climate change’. I wonder why...

[Incidentally, I'm led to believe also that currently there are more trees in the northern hemisphere than there have ever been in Earth's history].

• Recently, they’ve again been postulating the idea that the Earth is actually now cooling.

...and through all this, we’re STILL being taxed and penalised on the basis of so-called ‘man-made climate change’.

THE POLITICAL INFILTRATION (HIJACKING?):
After initial being taken in with the whole issue of - at the time 'global warming' - Thatcher (after researching and comparing both sides of the argument) eventually changed her mind and came to the conclusion: “Global warming ‘provides a marvellous excuse for worldwide, supra-national socialism’”.

Also, check out:

After all the debates I've seen (the most rational seemingly from the skeptical viewpoint) AND the history (in my opinion VERY IMPORTANT) starting long before the presented 1922 point, I find myself firmly on the skeptical side. I fear that the whole issue is very dangerous - politically - and in itself may lead to (particularly third-world) human/animal destruction not from so-called mmcc/gw but from unnecessary efforts to change what is a natural process having occurred cyclically for millennia.

[bradrowland]

Best explanation without being condescending or Snarky. Actually making me rethink a few things. CO2 is still absorbing X amount of energy regardless, but where the energy is being absorbed (non-troposphere) makes a difference.

[juliesteimle]

What gets me about this entire argument is how people ignore the word 'green' in the phrase 'greenhouse effect'. Hot does not equate dry.

[grahamlyons]

Thank you very much for this informative video.


You and I know that water vapour is a more effective GHG and more prevalent than CO2. So it is logical to assume that WV's warming effect is much stronger than CO2's. But your point about warming from CO2 in the upper atmosphere (from which water vapour has been "frozen" out), can be challenged on two counts:
1. CO2 is the heaviest atmospheric gas, the bulk residing close to the surface; only a tiny fraction of CO2 rises to higher levels where it gets its own back on water vapour.
2. The same frequency band of the sun's radiation, that 'low' CO2 captures and re-radiates, will also, of course, be captured by high-level CO2 molecules. And they will radiate some heat downwards. ... Yes, but to no avail, since the latter's radiation will encounter, either water vapour, whose radiation-capturing frequencies largely overlap CO2's, or low-level CO2 molecules, already at their limit of flexing or rotating – in other words, already full up.

[johnnursall]

Modeling as I understand it is not "difficult" -- it is impossible.

[bradgrauer]

you never hear any of these climate alarmists that mentions the saturation rate of CO2 and the fact that the CO2 has gone up since last 19 years but the temperatures have remained about the same

[Echidna]

"Co2 is plant food" is a bad argument because I say it is a bad argument.

[gufpott]

It's a good explanation of the theory Mallen, with some evidence alongside. But the missing tropospheric hotspot is what convinces me.

The absorption of energy aloft should be accompanied by a temperature rise. The temperature rise has to be sufficient to radiate enough IR back to the surface to cause warming. As the mid atmosphere radiates in all directions (consider up versus down as sideways is only redistribution), the surface only receives about half of the ADDITIONAL radiated energy due to the rise in temperature aloft (OK it's a bit more complicated than this because a layer of the atmosphere is like a spherical shell, but my statement is approximately correct). It follows that regions of the atmosphere must increase at a significantly greater the rate of warming at the surface below those regions. That's the theory (see my first citation to confirm) and it is testable. It is a Popper-falsifiable representation of the question of CO2-induced warming. You can see a quite nice graphic in the first citation below, but the IPCC did a good presentation in AR4 Figure 9.1 and it's worth a look.

So we now have the theory, and we can turn to the question: what do we observe? My second citation below confirms the predicted pattern of warming in the key regions (parameterised as a "Scaling Factor" which could be tested) is not confirmed by observations. This position has now persisted for 10 years. As Feynman said (my paraphrasing), it doesn't matter how beautiful and elegant your theory is, if the data says it's wrong …. it's wrong.

Theory: Santer et al, 1995, "A search for human influences on the thermal structure of the atmosphere" (Quote from this paper: "The pattern of stratospheric cooling and tropospheric warming … is in accord with previous modelling work and represents the direct radiative signature of the change in CO2".)

Observation: Christy et al, 2010, "What Do Observational Datasets Say about Modeled Tropospheric Temperature Trends since 1979? " (Quote from this paper: "A key indicator of the response of the tropical temperatures in enhanced-greenhouse gas-forced models is that the ratio of trends of the TLT layer relative to the trend of the surface, Tsfc, should be about 1.4, i.e., a ―scaling ratio‖ (SR) of 1.4. Using observed trend values, the observed SRs for TLT are significantly less than 1.4, being ~0.8 ± 0.3. This suggests that on average, the model amplification of surface temperature trends is overdone, and that the observed atmosphere manages to adjust to heating processes without allowing (over decades) a temperature change in the troposphere at a higher rate than it changes near the surface. An alternate explanation is that the reported trends in Tsfc are spatially

inaccurate and are actually less positive. A more positive surface temperature trend than reported here, of course, would make the disagreement with the models even more significant [7, 8]".)

Just in case you didn't quite catch Christy et al's polite phrasing for journal presentation … they are saying the models are falsified by data.

And before anybody gets excited about peer review of Christy et al's analysis and conclusion, the above paper led to a prolonged debate and challenge, mostly by Santer. The result was never overturned by Santer. Santer managed to argue that Christy's result could be changed somewhat, but not overturned and it still stands by a clear margin. Despite a decade of more evidence.

[lawsonhannah]

Mallen, The world would be a much better place if more people took your advice and actively sought out the best arguments against their positions. So many people are “ideologically possessed” where they just repeat what someone told them without every understanding why. You see this when people are unable to coherently defend their positions and resort to Ad Hom’s.