Science Literacy???

Someone by the name “Danny” tried to post a couple of responses to the Desperate Denial post. Having posted Neil deGrasse Tyson’s eloquence about the value of science literacy, I thought I might share the comments and let readers form their own opinions about where they fall on the “science literacy” scale.

It begins thus:

CO2 started out as .0003 percent of the atmosphere and now is about .00045 percent. Statistically speaking it takes a special kind of dishonesty to continue to claim that CO2 is warming the atmosphere. Do the math 450 parts per million is .00045.

Pardon me for saying so, but perhaps you’re not clear on the meaning of “percent.” Because .0003 percent is .000003, i.e. 3 parts per million. A simple mistake, but rather embarrassing for one who implores us to “do the math.” And by the way, CO2 concentration is now about .000405, not .00045.

The first comment is followed by this, a response to a comment about Christopher Booker’s denial of evolution:

Evolution is an unproven theory. Relatively, the most proven scientific theory ever thoroughly debunks Evolution yet the lemmings will still buy evolution, the same way they claim global warming is true. CO2 started out as .0003 percent of the atmosphere and now is about .00045 percent. Statistically speaking it takes a special kind of dishonesty to continue to claim that CO2 is warming the atmosphere. Do the math 450 parts per million is .00045.

Before you have a conniption fit in your reply study Relatively for a few weeks and think about .00045 percent and how insignificant that number really is.


I promise we won’t have a conniption fit. Just a good laugh.

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64 responses to “Science Literacy???

  1. There’s no kind of ignorance like ignorance that claims to be knowledge.

  2. Yeah …. I don’t know what to do with these kinds of comments and posts. If they are in a really public place, e.g., New York Times or Financial Times or equivalent, I usually take the trouble to point out the mistakes, not because I’m trying to convince the poster, but because the remaining readership might learn something from the exchange.

    But in this case, while I can’t get myself to laugh, since this kind of thing is all too prevalent, I can at least do a deep sigh.

  3. Relatively, the most proven scientific theory ever thoroughly debunks Evolution….

    We need more info! I can’t find this in a Google search — even correcting for ‘relativity.’

    New B.S. is always more interesting than old B.S., but I suspect this is just some creationist meme that has been mangled beyond recognition.

  4. Not that he’s high on my list of people to care about, but I hadn’t realized that Christopher Booker doesn’t believe in evolution.

    Slightly more interestingly, Roy Spencer is a creationist. His colleague John Christy is more circumspect, but is an evangelical Christian who spent four years as a Baptist missionary in Kenya. One wonders how much the Christian religious ideology known as Dominionism* may influence their contrarian stance on AGW and their skepticism that human activities may cause serious or catastrophic harm to terrestrial ecosystems.

    * from Genesis 1:26 and 1:28
    And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth…
    And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth.

    • tbf his article on evolution, was more about the arrogance of scientists and modern day science (I suspect it comes from an inferiority complex couple with a natural contrarian mind-set that simply does not like to be told what to think) , but he did pepper his article with ill informed claptrap about the evolution as a theory

      the article is linked to in my comment on the “desperate denial” post

    • Amplifying Magma, Roy Spencer signed the Evangelical Declaration on Global Warming, promulgated by the “Cornwall Alliance for the Stewardship of Creation” in 2009. It’s a frank statement of religiously-motivated AGW denial (emphasis mine):

      We believe Earth and its ecosystems—created by God’s intelligent design and infinite power and sustained by His faithful providence —are robust, resilient, self-regulating, and self-correcting, admirably suited for human flourishing, and displaying His glory. Earth’s climate system is no exception. Recent global warming is one of many natural cycles of warming and cooling in geologic history.
      We deny that Earth and its ecosystems are the fragile and unstable products of chance, and particularly that Earth’s climate system is vulnerable to dangerous alteration because of minuscule changes in atmospheric chemistry. Recent warming was neither abnormally large nor abnormally rapid. There is no convincing scientific evidence that human contribution to greenhouse gases is causing dangerous global warming.

      IOW: to Hell with the evidence, AGW can’t be real because God wouldn’t allow it. The rest of the declaration boils down to argumentum ad consequentiam — poor people need cheap energy, yada, yada.

      IMHO any scientist, no matter how lofty his credentials, who signs such a statement forfeits all claim to scientific credibility on the subject.

      John Christy, while not a signer of the declaration, is often claimed as an ally by the Cornwall Alliance. For example, their website reprints a 2006 OpEd by Christy, with an Editor’s Note attached:

      Quite likely the one Southern Baptist who best combines Biblical and theological training with scientific expertise in climatology and global warming studies, Dr. John Christy, an ordained minister former Baptist missionary as well as senior research scientist at the University of Alabama, Huntsville, is an expert reviewer for the UN International Panel on Climate Change and a leading critic of global warming alarmism. As an expert reviewer for the IPCC, he ironically shares the Nobel Peace Prize awarded chief alarmist Al Gore. This article, which we ran in the newsletter shortly after it first appeared in the Wall Street Journal, bears repeating now in light of developments in the Southern Baptist Convention.

      BTW, following the influential 1967 Science article by Lynn White, I’ve sometimes used dominionism myself to describe the attitude toward nature informed by Genesis 1:26 and 1:28. As BPL points out, though, today the term is more commonly applied to political ideologies calling for Christian theocracy, essentially the Christian version of Islamism.

  5. Why don’t we ever hear “I just can’t believe clouds have any effect on climate”?

  6. Much like the “Theory of Gravity” — we have jumped out of the airplane, falling without a parachute… and blissfully unaware, we think since we have not yet hit the ground, we got away with ignoring that harsh rule.

  7. Philippe Chantreau

    It is truly unfortunate that the internet echo chambers now provide validation to all sorts of nincompoops. We have gone from “everyone can have their opinion” to “all opinions are equally valid”, as if opinions acquire validity just by virtue of their existence. We never had better means of being informed and it seems we are more poorly informed than ever…

  8. I sincerely hope that poor Danny’s time spent relatively studying things hasn’t convinced him that it’s okay to spend more than 1 hour breathing air which contains a pitiful 400ppm of carbon monoxide.

    • Or the tiny amount of 20ppm of Cl2.

    • The concentration of atmospheric ozone averages out to 0.6 ppm. Obviously at this concentration it can have no effect, and reducing its concentration further and creating an “ozone hole” will similarly have no effect…

  9. This is a bit of an apples to oranges comparison, but I think anyone who thinks that “Gee, 400 ppm sounds small” is an actual argument should be invited into a room with 400 PPM hydrogen sulfide.

    Hydrogen sulfide is the familiar rotten egg gas that you can smell at less than 1 part per BILLION. By 100 PPM, eye damage occurs and the gas no longer smells because the olfactory nerve is paralyzed. By 300 PPM, pulmonary edema can occur. The LD50 (lethal dose for 50% of people) falls between 500-1000 PPM depending on exposure time.

  10. climateweathermathmiscellaneous

    One can think of greenhouse gases as “active ingredients” with respect to global warming, and the bulk of the atmosphere as “inactive ingredients” with respect to global warming. Significantly increasing the amount of one of the significant active ingredients has a warming effect.

    Taking a small pill with a large glass of water wouldn’t imply that the pill would have little or no effect because it was taken with a much larger amount of a medicinally inactive substance. It would be silly to suggest that doubling the dosage would have no effect only because the pills are so small compared to the water that they were taken with.

  11. Point out to Danny that it only takes about 150 *nanograms* of botulinum toxin, or about 0.00000000015% of your body weight, to kill an adult human being *dead*. Small amounts of things *can* have large effects.

  12. Alll the O2 and N2 in the atmosphere is irrelevant since they’re diatomic molecules that do not have wide absorption bands in the infrared. The 1% of monatomic Argon is also completely irrelevant. Its the CO2 and H2O that matters.

  13. Let’s see: The atmosphere is one-fifth oxygen, all animal life including humans depends on oxygen, photosynthesis is what supplies that oxygen and maintains its level in the atmosphere, and that photosynthesis depends on…wait for it…CO2?

    Nah, not possible–there’s only 405 parts per million CO2 in the atmosphere! Just a hoax, this AGW stuff. Anyone who’s scientifically literate can see that.

  14. a common comment I see from AGW deniers, creationists and twoofers et al is one of “proof”

    they demand it – after all if they were persuaded/influenced simply by an overwhelming weight of evidence, they would not be where they are – down a deep dark rabbit hole!!

    if you debate creationists for any length – or observe their arguments, they talk of “observational science” (what they mean is stuff you can “prove” in a lab)

    and “historical science” – so with this brand of nonsense science, all bets are off.

    because you cannot put the Grand Canyon in a lab, observe and hence “prove” its formation over 100’s of millions of years

    the alternative “6000 year old flood” hypothesis is equally valid/true

    similarly AGW deniers want you to prove AGW, presumably by releasing a drop of CO2 and then running outside and observe a temperature increase

    it is a mental construct that allows them to function as human beings – to a point

    • I don’t even think that’s it, Tadaaa. Such arguments to them are purely a matter of style. For the radiative forcing that comes from CO2 interaction with infrared and the Blackbody Effect is a special case of the same for many different materials and N-atomic gases (N>2). Such science is the basis of a lot of practical engineering, with the resulting working constructs being proofs-by-example. Thermal balance of on-orbit satellites is one striking example. Less striking but far more substantial are the processes involved in semiconductor manufacturing, including measuring material temperatures without coming in contact with them, as well as calculations of thermal conduction across layers of different materials. So, to me, either they are being highly selective, or that machine (science) deniers are using was deposited there by angels and is due for its Regeneration Spell from Hogwarts.

      • I disagree hypergeometric

        I can only speak from my own personal experience though

        I came to the AGW debate (a few years ago) with zero knowledge of climate science (and ashamedly, science in general)

        in fact I think I probably erred on the “it’s a bit of a con” side of the debate – and bought into some of the myths

        you know, they spouted global cooling in the 70’s, they keep changing the name – AGW to climate change, it rains – climate change, drought – climate change yada yada

        so initially (and unashamedly – I am not a scientist after all ) I had to judge the subject on rhetoric alone

        and pretty soon I found the rhetoric / logic / modus operandi of the deniers to be eerily similar to the twoofers and creationist I had been engaging online with

        the classic sign was continually linking to dubious sources (blogs / YouTube videos) when I asked for a source, another was the seemingly simple statement that with 2 seconds thought is actually gibberish “the towers fell straight down” err that’s gravity, ”C02 is a trace gas” – err so what, that tells us nothing about the physical properties of CO2.

        which lead me to ask myself questions – and actually the most interesting one was “what exactly is a climate scientist”
        the answer lead me to realise that AGW is built on simple reproducible physics, then I read up on the science – most is beyond me tbh, but I am intelligent enough to get the gist

        so along the way I learnt the basics (basics that I should have learnt 30 years ago at school – I did a degree in History btw)

        I learnt what a scientific theory is, what the building blocks that make up a scientific theory are – and none involve proof

        So I would not be so quick to prejudge the basic level of what science is, I suspect quite a few would actually think it involves “proof”

      • Thanks for your insight, Tadaaa. Of course that is a personal accounting, so it’s fine.

        Yeah, maybe the “proof” part comes from a jurisprudence approach to Science rather than a statistical one. No one “debates science” any longer. That was done around the time of Louis Pasteur. It’s evidence, prediction, experiment, and consensus on evidence.

        It is curious, however, that in Mathematics, while proof is a big deal, and, in fact, modern Mathematics has been called the science of proof, proofs are not accepted until there is consensus. That is, you cannot do cutting edge Mathematics on your own. You need community. In that respect, I don’t think it’s different than the sciences.

  15. Heres a more fun counterexperiment for ppm deniers: Put 1ppm of LSD in a glass of nonchlorinated water. Drink and report back.

  16. what I find amusing is that .00045 percent is undoubtedly a low concentration of “something”

    yet the deniers trump it with their “trace gas meme” which has .000000 percent science in it – amazingly they manage to get an even lower concentration!!!!

    and interesting correlation to the percentage of “active” ingredient in a homeopathic remedy

  17. One might suspect that ‘Danny’ is merely a Poe or troll with an aim to tweek our noses. But it really doesn’t matter, since there are people who really do buy into this sort of argument.
    It makes me want to see a chart of the ‘No True Scotsman’ ranking of denialist arguments (similar to the 5 stages of denial) with a finer resolution of detail.
    Can you imagine a ‘luke warmer’ looking at such a chart and scoffing at the ‘silly arguments’ at the simplistic level, while patting themselves on the back for being so much more informed?
    Science literacy is a major key to having an informed voting public, but I think the bigger and arguably more important aspect is epistemology.
    It has recently become a major talking point in multiple forums that apparently more than 40% of the US public has no idea about how to discern
    plausible and fact based information from ideological BS and outright propaganda.
    The skeptical ‘the science based variety’ community has been working on this issue for decades, while the rest of the reality based community has tended to think that all they needed to do was present valid fact based information to educate citizens, and that would (should) be sufficient.
    In a purely rational world it would be. Sadly, that is not the world that we find ourselves in.

  18. I’ve got a very effective way to visualize PPM for the layman (me). 1 cubic meter = 1 million Centimeter3. So going from about 250 PPM to 500 PPM is going from a quarter liter of drink to 1/2 liter for a given lunch “”. Now multiply by the number of m3 in the room, and suddenly, the “nothing” of PPM become a bunch of glass, floating in the space around…. very impressive, I guess. ,

    • Philippe Chantreau

      Actually Philippe (and to clarify, we a re two different persons), I fond this demonstration on YouTube to be much more explanatory than anything else than can be said. It is especially relevant, since it shows how light transmission is affected by “small” amounts or “small” changes. If we could see CO2, it would be very similar to what is shown in the clip. Don’t know if Tamino will let that go by but it’s worth watching:

      [Response: Ordinarily I don’t permit embedded video. But this is good enough to earn an exception.

      In the future, please link to the video on YouTube rather than embedding.]

      • Is this informative or misleading? The idea was that the ink blocks visible light in the same way as CO2 blocks IR. But they seem pretty different to me. I’m reaching pretty far back in time for the chemistry, but I don’t think I’m wrong.
        When you mix CO2 into air at 400ppmv, you have a gas in a gas where approximately 400 out of every million molecules of air is CO2. The molecules are more or less of similar size and the properties of gases are such that each molecule takes up the same volume. On the other hand, with ink you are mixing a solid – carbon black – with very large molecule size, into a liquid, water. Liquids and solids don’t have the same mixing properties as gases – Avogadro’s Law and all that.
        Also, CO2 absorbs IR and re-emits it, whereas ink absorbs visible light, but does not re-emit it.
        I’m not a skeptic, denier, or any other such thing, but I’m just not sure this gets the point across properly.

        [Response: What a lame excuse for not believing your own eyes. The ink does re-emit visible light, just not enough to satisfy you. And liquids don’t mix volumentrically like gases — you think that invalidates the clear demonstration that such tiny amounts can profoundly effect the transmission of radiation? Seriously?

        The demo is very informative. You are scraping the bottom of the barrel to find it misleading.]

      • “Is this informative or misleading? The idea was that the ink blocks visible light in the same way as CO2 blocks IR. But they seem pretty different to me.”

        It’s disprobative, to invent a word, because the original (foolish) claim is that ‘400 ppm is really, really, small, and so can’t matter.’ Quite obviously, it can and frequently does, as this video and the numerous examples already given show. Of course none of them are perfect parallels to the CO2-in-atmosphere question. But it had already been settled by actual study. At present, the project is to illustrate for folks who have a reasonably ‘open mind’ why the ‘too small to matter’ claim is, indeed, too foolish to matter.

      • JT,
        First, I think you are missing the point of the video–which is that a small addition of material can change the optical properties of the medium dramatically.

        Second, although if left to itself, a CO2 molecule would re-emit the IR photon…after about a microsecond. However, a microsecond is an eternity of the molecular scale. What happens more often than not is that the excited CO2 molecule collides with another molecule (most likely N2). Now, remember that the vibrational mode of CO2 involves translation of the C and O atoms. These can transfer the excitation energy into the kinetic energy of the N2. The result is that the IR heats the entire atmosphere, not just the CO2.

      • Tamino, I’m sorry if you think I’m scraping the bottom of the barrel. I agree with you that the video does demonstrate that small amounts of material can have a large effect on the transmission of radiation. It also demonstrates that the action of pigments is similar to the greenhouse effect because both involve the absorption of radiation. Perhaps that will be helpful to people who are trying to get their minds around how the greenhouse effect works.
        On the other hand, (i) one of the key points to understanding the greenhouse effect is understanding how the radiation is re-emitted, and (ii) the materials used likely exaggerate the absorption effect – maybe a lot (this is not a lame point.)
        Finally, about ink. Yes, it does emit some visible light – but carbon black is a good black. It doesn’t emit much visible light. Most of what it emits is IR. In fact, the paint industry devotes a lot of effort to finding alternatives that do not heat up so much.

      • I liked Snarkrates’ addition to the thread, i.e., the explanation of the transfer of kinetic energy to non-greenhouse gases like N2.

      • I’m the one who made the ink video. Since making it, I have heard many other explanations about why CO2 in “small amounts” can have such a big impact.

        One I like is about duck hunting. Imagine a park where people with permits are allowed to shoot ducks. Imagine there are 10 hunters with permits and 10 observers without permits. Let’s say this “50% concentration” of hunters kills on average 20 ducks an hour. Now let’s say the public gets fascinated by this carnage and 10,000 observers show up to watch 10 hunters kill ducks. Now the “hunter concentration” is just 0.1% (a trace amount!) but they are still killing 20 ducks an hour! The bottom line is that O2 and N2 are not greenhouse gases so it doesn’t matter how much of the atmosphere they make up. All that matters is the total amount of CO2 (and other greenhouse gases) — not the percentage.

        Another way to look at it is if you go to the top of Mt. Everest without supplemental oxygen, you are probably going to die even though the oxygen concentration is still about 20%. What matters is the number of O2 molecules, not their concentration.

      • Dan, that is a beautiful additional way to explain it.

        I would like to add, that the experiment does not show that there has to be a greenhouse effect, just that the claim that 400 ppm cannot be enough to have an effect is bogus. They are welcome to try a more intelligent claim.

        (Or to be honest, I would prefer not to be bothered with this nonsense in 2016. Everyone can notice that a clear night is colder than a humid or cloudy night. If you feel an enormous need to disprove the greenhouse effect itself, please first submit your article to a scientific journal.)

      • “Everyone can notice that a clear night is colder than a humid or cloudy night.”


        William Charles Wells did, back in the early years of the 19th century, and spent quite a bit of time making careful measurements of that and related phenomena. He ended up winning the Rumfoord Medal (not to mention influencing none other than John Tyndall). If you enjoy a spot of science history–and climate change ‘pre-history’–you may like this essay:

        (Not new, but also not linked here for quite a while).

    • Philippe, another way to frame the numbers with respect to the gasses CO₂ and ozone, and their presences in the atmosphere, is here:

      It’s worth a look…

  19. Henk Schuring

    Completely off topic, I’m sorry. But I stumbled across this applet (about fitting a model to almost all temperature data sets taking all kinds of influences into consideration) and I would like to know if it is useful:

  20. Quotes from two ‘famous’ Professors’, from two separate scince disciplines whenever this topic comes up

    “We’ve arranged a global civilization in which most crucial elements profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces.”
    ― Carl Sagan

    The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that ‘my ignorance is just as good as your knowledge.” ― Isaac Asimov

    Sagan’s in particular seems inceredibly prescient.

    • Great quotes,

      On of my fondest memories as a child was the Carl Sagan Cosmos series

      I vividly member watching the episodes through one long hot London summer in the 80’s

      I especially remember his description, billions of years into the future, of the last perfect sunrise (before the sun begins its death spiral)

  21. Not directly relevant, but here’s my (evangelical Christian) stance on Dominionism:

  22. Only very vaguely related, but I don’t get good ideas that often, and it seems a shame not to share them. Its about the future of science:

  23. If you “do the math”, you can calculate that 280 ppm (or 400, or 600…) is enough to block a lot of infrared in a few meters of gas, let alone the whole atmosphere which is kilometers high.

    It’s completely irrelevant if it’s a figure that sounds small to the layman.

    Maybe the calculations with the Beer-Lambert Law could be worth a post, Tamino?

    • Indeed, denialists often bring up the idea of saturation; that is, the claim that 400ppm of CO2 is so effective at absorbing infrared that further increasing atmospheric concentration can’t possibly matter. I’d suggest they argue the point with the “trace gas” crowd, but it’s often the same people making both arguments.

      • That was a state of the art question–in 1901.

        “So, if a skeptical friend hits you with the “saturation argument” against global warming, here’s all you need to say: (a) You’d still get an increase in greenhouse warming even if the atmosphere were saturated, because it’s the absorption in the thin upper atmosphere (which is unsaturated) that counts (b) It’s not even true that the atmosphere is actually saturated with respect to absorption by CO2, (c) Water vapor doesn’t overwhelm the effects of CO2 because there’s little water vapor in the high, cold regions from which infrared escapes, and at the low pressures there water vapor absorption is like a leaky sieve, which would let a lot more radiation through were it not for CO2, and (d) These issues were satisfactorily addressed by physicists 50 years ago, and the necessary physics is included in all climate models.

        “Then you can heave a sigh, and wonder how much different the world would be today if these arguments were understood in the 1920’s, as they could well have been if anybody had thought it important enough to think through.”

        And, I would add, be thankful for Guy Callendar, who took time away from his work as a steam technologist (and his beloved family, not to mention his tennis game!) to think through the problem a bit more, and to write persuasively enough about it to revive the whole topic in the scientific literature.

      • The fundamental thing that the Beer-Lambert law argument misses are the radiative transfer calculations. The CO2 isn’t all at the same temperature – temperature drops with altitude in the atmosphere – and the IR radiation isn’t just emitted from the ground, and partially absorbed on its way to the cold space background. IR photons are emitted and absorbed and reemitted all the way up through the atmosphere, with the effective temperature of the radiation dropping all the way up.

        What increasing the CO2 concentration does is increase the optical depth of the atmosphere and reduce the absorption scale length. That means that the each part of the atmosphere see warmer effective temperatures above them (because the part of the atmosphere they can see is effectively lower and warmer), and the net heat transfer upwards is reduced.

        Something like this is standard practice in cryostat design – we use multiple layers of space blanket like “super-insulation” between the vacuum shell and the cold stages to massively reduce the radiative heat load on the cold stages (although each layer is reflective, it’s not perfectly so, and there is blackbody absorption and emission of radiation). Each layer of the insulation is passively cooled by radiation to the next layer in, while absorbing heat from the next layer out, and each layer reaches progressively lower equilibrium temperatures. Even though each layer of insulation perfectly blocks radiation from inside it to outside it, you still need multiple layers to reduce the radiative heat transfer, and adding more increases the insulation.

        The critical thing that makes this work is that the radiative heat transfer between adjacent layers (in a fixed waveband) goes as the difference in the cubes of the temperatures of the layers, and so as you reduce the equilibrium temperature from layer to layer, the total radiative heat transfer across the stack drops. This doesn’t work for conductive heat transfer which goes as just the temperature difference between layers.

      • Actually, I think I’m somewhat wrong in that last paragraph, because we are talking about radiation around the peak of the blackbody spectrum when we talk about CO2 IR emission/absorption. It’s not strictly the cube of the temperature difference which applies well above the blackbody peak, but some lower power (still greater than one though because we are above the Rayleigh-Jeans law regime).

      • @ Doc snow

        thank you for the article on Guy Callendar, a fascinating read ,

        the stuff around FIDO was really informative and actually quite close to home – literally

        My Grandfather (in-law) flew with the Pathfinder Squadron in WW2 he was involved in one of the biggest RAF tragedies of the war – when fog enveloped the whole of southern England – known in the RAF as Black Thursday, planes (Lancaster’s and Mosquitos) returning from a bombing raid to Berlin had to land in atrocious conditions, many planes crashed on landing, 100’s died

        Bourn Airfield, where he landed – did not have FIDO, it was only available at a few airfields in Southern England, but it did save lives that foggy night

        and weirdly, although born in London, I now live very close to Bourn Airfield – and my elder brother went to the same school as Guy !!

    • I’m not physicist enough to know how the following would work: If we constructed an Earth at the same distance from the Sun which was airless, and of course waterless, except for a pure CO2 atmosphere amounting to .3mm Hg (e.g., the amount we have now), what would we get?

      • We have a good experimental lower bound on that – the Moon. Since water vapor is a major component of the baseline greenhouse effect (and also does a significant job in retaining heat over night), most of the Earth’s greenhouse effect would be gone (as well as that from methane, etc.), but there’d still be a bit from the CO2.

        So you’d get something a lot colder than the Earth, but not quite as cold as the Moon’s mean temperature (220K to 180K at equator and 85° latitude). Variations between night and day time surface temperatures would also be much greater than on Earth, but much less than on the Moon (due to the shorter days).

  24. I made a YouTube video a long time ago about the “CO2 is a trace gas” myth. I did an experiment where I put 280 ppm of ink solution (actually 28 ppm of ink) in water an observed the effect:


    [Response: It has already been embedded in a comment above.

    Please, no more embedded video in comments.]

  25. It really is the absolute amount that matters, and not the volume fraction. There is no volume fraction term in the Beer-Lambert-Bouguer law or the equation of radiative transfer.

    And 0.1 ppm of fluorine in the air will kill you.

  26. Philippe Chantreau

    Sorry about the embedding Tamino. I had run into this before. WordPress does it automatically and I’m not sure how to disable that function.

  27. A little over twenty grams of HCN for a non-obese person. Yeah, insignificant.

  28. I tried to submit this one to “Physics Today,” but they weren’t having any: