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Why Are We Sure We're Right? #2

Posted on 4 May 2012 by Rob Honeycutt

This is a second installment in this series exploring why we are sure we're right on climate change issues.  In part 1 we heard from Skeptical Science authors Dikran Marsupial, Glenn Tamblyn and Ari Jokimäki.  This time I'm going to take my own stab at the question, and post the thoughts of Dana Nuccitelli and Andy S.

Rob Honeycutt...

What always strikes me as I read both pro-AGW and "skeptic" articles and science on the subject of AGW is this: Absolutism vs relative uncertainties.

On the "skeptic" side I continually read how this is a big hoax, scientists are altering data, "hiding the decline," they are in it for the money, they are perpetrating a fraud, we can't possibly know what the cause of warming is, or nothing we humans could do could possibly alter the climate. These positions range from the extreme with Lubos Motl keeping a list of scientists "who will be jailed," to the mainstream skeptics like Lindzen and Spencer who also attempt to lay out a case for fraud. This entire range of opinions on the skeptic side is absolute in the position that CO2 could not possibly have the effect climate scientists say. Across the gambit of arguments I see very little in the way of consistency. Any argument against AGW is okay and doesn't need to be internally consistent with any other argument against AGW.

On the side of science I read relative uncertainties rather than absolutes. There is a consistent, yet complex, message presented by a large body of published research. Atmospheric CO2 has radiative properties. We are dramatically increasing CO2 levels. Warming is occuring. Ice is melting. Glaciers are melting. Paleo data suggests there are feedbacks. There are uncertainties in the climate response but those uncertainties are constrained via multiple lines of evidence. The puzzle explaining AGW is well filled in, though not all the pieces are in place. It is unlikely adding the final pieces of the puzzle will change our understanding of the final picture.

To flip my own question around, I find the side that is "sure" about their position tends to be the "skeptic's" side. The more compelling argument, for me, is the relative and constrained uncertainties. Given this, there are decisions to be made. How do we take what is an overwhelming amount of evidence suggesting AGW is going to be a problem and balance that against the cost of action within the relative uncertainties?

Is there a chance that climate scientists have gotten this all wrong? Certainly. But the evidence is so overwhelming that the science is correct that it would be morally reprehensible to not take action to curb our greenhouse gas emissions.

Dana Nuccitelli...

We're not sure we're right - science is not about certainty, but rather about probabilities. Many different lines of evidence support the human-caused global warming theory, and that the Earth's surface will warm on average approximately 3°C in response to doubled atmospheric CO2. There is a chance the climate sensitivity to CO2 may be lower, but the odds of low sensitivity are slim, and it would be poor risk management if we were to ignore the high probability that our current path poses substantial risk for future generations.

Ultimately, as described so well by Greg Craven, our response does boil down to risk management. The scientific evidence clearly supports the human-caused global warming theory, and very harmful consequences are a possible (and probable) result if we continue with business-as-usual. The consequences if we choose to address that risk (by reducing greenhouse gas emissions) and the theory is wrong amount to a very small economic impact.

In short, we think we're right because the scientific evidence overwhelmingly supports our position, and reducing greenhouse gas emissions is clearly the correct risk management approach even if we're somehow wrong.

Andy S...

For most of my career, I have worked as an industrial scientist, either as an employee or consultant. It has been my responsibility to offer advice to employers and clients on when to go ahead, when to wait to get more data or when to drop a project. In practice, the data are usually inconclusive, often there is a real risk that the underlying technical model is wrong, and even successful outcomes have a large range of uncertainty. How do I know I’m right? I don’t. All I can do is honestly lay out all the pros and cons and use my best judgement in my recommendation.

Philosophically speaking, we can never claim perfect knowledge or certainty, especially about how events will unfold in the natural world. The best that we can do is to avoid bias, use multiple lines of evidence and to refine our ideas through discussion, criticism, testing and logic. From all my reading and attending conferences over the past few years, I am sure that climate science meets the highest standards of enquiry. It is clear beyond any reasonable doubt that our greenhouse gas emissions, mainly from fossil fuel use, are changing the atmosphere and that this will change the climate. It is going to get hotter and weirder, even if nobody knows precisely how hot, how weird or how fast the change will be.

No successful businessman can wait to make an investment decision until he has proof that all uncertainties and risks have been reduced to zero. Any delay, in the real world, means that the opportunity will go away or that someone else will seize it. Some climate skeptics claim that important decisions cannot be made until all the risks and uncertainties have been eliminated. These people obviously have never worked in a successful business.

We can’t ever know we are right. All we can do is rely on the best information we can get. Luckily, the knowledge provided by modern climate science is solid and consilient. But reliable information is only valuable if we act on it.

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Comments 1 to 50 out of 58:

  1. "the Earth's surface will warm on average approximately 3°C in response to doubled atmospheric CO2."

    Based on what we know, this seems a reasonable statement, CO2 should reduce emission to space and given observations, around a three degree rise in temperatures should be required to return emission to space to pre CO2 increase levels.

    But observations of surface temperature change indicate a rate that's about half of the 3 degree rate.

    We know we are right that CO2 should increase surface temperature, but we don't know how much.
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  2. Lucas @1 - surface temperature changes have been consistent with a 3°C equilibrium climate sensitivity. See here, for example. We'll have more on this issue next week as well.
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  3. Typo: Rob 3rd para 'dramaticly'.
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    Moderator Response: [RH] Thanks.
  4. Now, I'm angry:
    Heartland Billboard Campaign
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    Moderator Response: [Dikran Marsupial] Better just to raise ones eyebrows and shake ones head in sadness, at least for the blood-pressure! The weekly digest thread is probably more appropriate for further discussion.
  5. Lucas Verma @ 1

    Mind your words. 3°C is not a rate, it is equilibrium sensitivity. Transient sensitivity is closer to the idea of a rate.
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  6. Rob, Dana, Andy,

    sometimes ordinary language is better than philosophy 101. I hope you're sure that it is unwise to jump off tall buildings, unwise for kids to take up smoking, and unwise for earth's humans to greatly increase the amount of greenhouse gasses blanketing our one planet, and unwise to persist in acidifying the oceans.

    btw a prominent link to the OA not OK pdf would be nice. It might be added to the little rectangular image as the letters 'pdf'.
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  7. Not being a scientist, my discussions with friends and skeptics here in the US tend to be less clinical and much more philosophical, I think. But I do like to ask them one question:
    "What would it take to change your mind from being a skeptic to a believer?"
    Is there a scientific organization, a temperature, a climatic series of events, or anything that will make them consider the reality of AGW? I never get an answer, which leads me to believe that nothing short of a tag on CO2 molecules which says "from car exhaust" will ever change their minds.
    I tell them that if trusted scientific organizations such as NAS or AGU become skeptics, I will change my mind. Or if my candytufts bloom on Mother's Day like they used to rather than 2 weeks earlier like they have for the past number of years, I will change my mind.
    But I can't even get them to even consider the question. Which tells me they are VERY sure that they are right. Or even unwilling to consider the alternative.
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  8. I think the absolutism in the arguments of the "skeptics" needs to be pointed out. It is not consistent with scientific thinking/reasoning for a start as you said Rob. And the lay "skeptics" think in absolutes also. Cognitive behaviour therapy/rational emotive therapy is about learning to drop the absolutism (never,always,all,none) and people labelling (left wing conspirators, anti-progress greenies)and thinking more realistically about specific issues. The consequence of more realistic thinking is more constructive behaviour and feelings. The skills of realistic rational thinking are life skills which enhance self efficacy in challenging situations. I think "skeptics" need to become more aware of their irrational,absolutist and unrealistic thinking ie
    " ALL the lines of peer reviewed evidence supporting AGW theory are completely wrong as are all the leaders in the relevant sciences and all their expert organisations and I will never accept any evidence supporting AGW theory and become very angry when lefty greeny alarmists talk about reducing emissions". A more realistic rational way to think is "There is now a very large body of peer reviewed evidence across multiple lines of investigation supporting AGW theory. The leaders in science and their expert organisations are confident that AGW is unlikely to be wrong. It is therefore unrealistic for me to expect that all the peer reviewed evidence and leading scientists are wrong and that all people who accept this evidence are lefty greeny alarmists. Since most of the warming has been bought about by using fossil fuel energy to create wealth and prosperity in the developed world over the last 150 years and the significant threat AGW poses to human health,food security, geopolitical stability and the biosphere, it is prudent and responsible to bring together our best brains and expertise to plan and implement risk management strategies, to reduce emissions as quickly as possible and to disengage with politicisation of the issue. I understand that this will cost money but am not prepared to leave a legacy of irreversible climate disruption to the next generation". It would be nice if a reasoned statement was made for people to publicly declare whether or not they agree so their children who will face the consequences will know whether their aging parents were part of the problem or part of the solution and signalled for government to act on their behalf on this issue.
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    Moderator Response: TC: All capitals converted to bold for compliance with the comments policy. Compliance is not optional, and we do appreciate your cooperation in this.
  9. I don't usually comment because of being "just a nurse", however, reading Part 1 and part 2 shows something rather glaring to me. It is the difference between the way a scientist in the field presents a considered approach and the way the media reports anything.

    I was in the audience (somewhere at the back where no-one could recognise me on TV it seems) for the Q & A and documentary titled "Can I Change Your Mind About Climate Change". One thing I took away from that was the comment ( can't rememember who exactly said it - most likely Rebecca Huntley) that we cannot sustain a fear response.

    Media reporting is designed to evoke emotional, even visceral, responses. This, I think, more than anything has driven the polarization of responses to the information.

    I have also recently consumed, with great glee, the book "Wilful Blindness" by Margaret Heffernan. In the early chapters she shows how people who are presented clear evidence refuting sometimes rather bizarre beliefs, don't change their beliefs, but instead become more extreme and polarized. There needs to be substantial internal discord before change is possible.

    Somewhere between media-fuelled reporting and the drivers of wilful blindness lies the reason so many people find it difficult to keep an open mind.

    What saddens me is knowing that for some people the fear element is a real, very-close-to-home factor as they lose their fresh water to salty seas. More than anything, there need to be new ways to communicate that don't rely on strategies that polarize and feed wilful blindness.
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  10. JimF, I have tried asking fake skeptics "What observation, real or hypothetical, would convince you that global warming is happening?", or "If global warming were really happening then what do you think would be different from what we see today?"

    They are good questions because if they say nothing would persuade them, or ignore the question, then it shows that their viewpoint is not evidence based i.e. no evidence would ever convince them, no matter what.

    A common response is for them to start handwaving like miniature windmills, or ask for impossible data e.g. sunspot counts going back to the age of the dinosaurs. The closest I got to a real response was someone who said that if global warming was really happening then the temperature rise would be much faster than it is.

    For that person at least I think the observations they want will arrive in the coming decades...
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  11. No serious skeptic really doubts that there has been surface temperature increase, nor that CO2 has radiative properties which may slow down heat loss.

    Where there is serious doubt is whether the planet's energy imbalance is currently growing or shrinking and the magnitude of the component forcings.

    Shrinking presents problems for the magnitude of CO2 and feedback effects especially clouds.

    There has been alarmism on both sides of the AGW debate. The looney skeptics should be discounted in the same breath as the AGW catastrophists.
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  12. Sapient Fridge@10
    I like your second question, so I will add it to mine.
    And you are right that it seems as if nothing will change their minds.
    I think that we all should realize the difficulty it puts on the believer side when they debate this issue vs. the skeptic side on the national stage. For those who watch and have not made up their minds they see one side say "We are not absolutely sure, but we THINK..." and the other side say "We are 100% sure and the other side is LYING..."
    Its much easier to then side with those who say they are sure and appeals to emotion, rather than the side that is not sure and appeals to scientific study.
    Just my take on it.
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  13. Victull,
    You have quite a list of hand-waving assertions. Care to provide any links or references for them? Provide links to AGW catastrophists you think need to be dismissed and why their claims are aurtageous.

    If you leave out the skeptics who concede surface temperature increase and CO2 radiative properties not many are left. Can you provide a list of who these remaining deniers are? What are their remaining doubts? Provide links to arguments that support their positions.

    Hand waving claims can be dismissed with a hand wave.
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  14. Actually, michael, victull has set up a straw man argument. The straw part is the undefined term "serious skeptic". As most understand the term, true Skepticism means using the scientific method to assess the known data and physics to derive the explanation that best-fits the totality of the data.

    Of course, this means real scientists are the real skeptics. And the vast majority of them accept AGW as a robust scientific theory (as shown by the vast hosts of scientific organizations and bodies, whose members number legion, who have issued position statements accepting AGW).

    Thus, the "serious skeptics" do not include the like of the fake-skeptics. Like Heartland groups, their minions and their paid puppets. Those who now fight a rear-guard, hand-waving battle of delay. Like claiming:
    "No serious skeptic really doubts that there has been surface temperature increase, nor that CO2 has radiative properties which may slow down heat loss."
    As all who have not been asleep for the past several decades know full well, victull postulates an empty, vainglorious pile of straw.

    Bereft of citation or substance.
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  15. Unfortunately, victull's claim is too ambiguous to seriously debunk. 'Doubts there's been surface temp increase' ... siince ...when? The end of the last glacial maximium? Last December?

    It is exactly this type of 'throw-down' denial that shows the weakness of the denialist position. And shows how easy the deniers think it is to fool the average person with vague claims.

    That's how we know we're right!
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  16. Sapient Fridge. Me too. It's good to know the answer to that question. I also make it clear what reasonable evidence would convince me that climate theory has serious flaws.If no evidence is good enough or question avoided, then no point producing evidence or even a serious discussion. As far as I can see must pseudo-skeptics are politically-driven, convinced any solution might limit their "freedom", raise taxes, expand government, or heaven forbid, involve international cooperation. No point in a private argument, and for public arguments (blogs), only worth rebutting errors for the benefit of other listeners.
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  17. victull, here's a paper with an estimate of the change in the imbalance: http://arxiv.org/pdf/1105.1140.pdf with the pertinent imbalance trend from fig 7d (assumes deep ocean mixing hence a slow climate response)
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  18. @ 11 victul- maybe he was reading a quote from MSNBC which reported the 'recantation' of global warming 'guru' J.E. Lovelock -http://m.edmontonsun.com/2012/04/30/global-warming-guru-says-not-so-fast
    who was quoted as saying ""The climate is doing its usual tricks. There's nothing much really happening yet. We were supposed to be halfway toward a frying world now," He doesn't specify where he got the information about the 'frying world"
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  19. JimF @7

    I am very sure that I am right in saying that all who believe in the warming of our planet is caused by CO2 are totally wrong, no matter which way bearing.
    I have two movies posted on youtube that clearly show that global warming is completely natural.
    This ....
    The_greenhouse_efect_completely-natural

    And the other is "our atmospher is opaque".
    Watch and then comment. ok
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  20. Tarcisio José D your linked video is partly addressed here to which I would only add that the shape of skew-T plots shown in the linked video is very dependent on concentrations of GHGs such as CO2.
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  21. Tarcisio Jose D @19,

    Your first video gives an account of the dry and moist adiabatic rate, and the consequences of surface heating, which is all very well, up until 6:40 seconds when you say, "That is the green house effect". That is not the greenhouse effect. You might as well say that Newton's second law of motion (F=ma) is the Universal Law of Gravitation (F=G(m(1)*m(2))/r^2).

    I'll certainly second Eric (skeptic)'s recommendation that you read my introduction to the greenhouse effect; and take up any issues there.

    However, I disagree with his comment about T-skew plots. Below the tropopause, the concentrations of greenhouse gases, at least within normal ranges, is irrelevant to the adiabatic lapse rates, except in that CO2 has a different specific heat to nitrogen or oxygen. Given relative concentrations, the contribution of GHG to the specific heat of air, and hence to the dry and moist adiabatic lapse rates is minimal.
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  22. eric @17

    Your graph shows a pretty flat imbalance at about 0.9W/M2 since 1998.

    James Hansen is claiming about 0.6W/M2 over the last 5-6 years. This confirms my suggestion that there is doubt about whether or not the imbalance is growing or shrinking.
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  23. victull, the "since 1998" idea is thoroughly addressed in threads here such as this one and many others. The paper I linked to is Hansen's latest so I will assume that it represents his most current conclusion: a long term increase in imbalance.
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  24. Tom, thanks for that feedback. I'll have to read up some more because my impression was a little different.
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  25. Yah, victull, what do you make of that? Everyone's wrong about the global warming, yah? I think a few of the warmistas tried to figure out why such a thing might happen. I mean, there's no other forcing change in the period . . . well, except solar dropping toward its 11-year low . . . and increased aerosols . . . and 1998 was a massive El Nino. Must be them darn supernovas gettin' all quiet. Still, it wasn't exactly chilly during the 2000s, it being the hottest recorded decade. And I hear ocean heat content was rolling right along, so nothing to get too worked up about. I mean, look at all those cooling trends. You'd think someone would notice the temperature dropping like that so many times.
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  26. We'll have some more posts on the global energy balance in the near future, and hopefully a published paper, if all goes as planned. Suffice it to say that the imbalance is still growing. Our recent Levitus post discusses a good demonstration of this continued growth.
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  27. Ok the more serious attempt to answer this:

    Why we're sure we're right

    To Claim:'we are right', we must define the words. 'We' has been traditionally been interpreted as being a specific communion of entities which can understand the english language, that means the humans who understand that this is written in english. 'We' has a broader definition too but I think this suffices for now. The specific communion of entities WRT to the context here would be the people who understand how the world works, i.e. the physics, AND accept there is a world which might be defined here as an assortment of environmental variables outside the entitys (if we wish to call a solipsist an entity) head, in the sense of the proverb: 'One can make a fence but not eternally block the world outside'. The dinosaurs of old times got this too late according to the prevailing theory of 'why there are no dinosaur fossils found on the layers of rock dated, by radiological measures that have and still can be reproduced in the laboratory containing an isotope counter, after the occurrence of a large crater on the Yucatan?' We humans (here encompassing all of our species) have at least had LONEOS and Catalina surveys among others, looking outside our comfort zone (broadly, the human biotope on earth (it's pretty large compared to nearly all other species on earth, only some marine species have had it wider; of mammals on land the next most widespread would be the rat and the dog I guess)), so some development has happened. Most people notice the outside world as a kid when they get hurt, so it's quite natural to be afraid of it. One might even make a bold assumption that the so-called 'theory of gravity' is accepted more readily than the GHG-theory because people have continuing first hand experience of it
    (f.e. saggy eyes).

    'right' is the tricky bit here, taken out of context this could mean almost anything. However, here we, as separate entities sharing some common chraracteristics (f.e. we're
    humans who can read and understand english), which is why the use of 'we' or 'these (inclusive)' (in case there are artificial intelligencies present) maybe allowed, have some context. In the opening chapter Rob Honeycutt tells us this is about climate issues and about being sure of these. So we might take the headline 'right' to mean 'certain', like an entity capable of self-recognition is. Talking to oneself isn't very fruitful, though, and one might even define the word 'talk' so it necessarily includes a receptive other entity, so if one uses language, it necessarily follows one assumes there is an environment that has beings capable of understanding your words, and thus there would be no 'Matrix' or at least if there was there would be no way of talking of it. Oops, might have made an error there.

    'are' is just a statement of being.

    So, after a brief exploration on the meaning of words, on to the subject. We're certain of the GHG effect and AGW because we talk (exchange information with others) of the
    measurements (one sort of entities), if necessary we check them repeatedly (in order to rule out the possibility of changing physical constants), try to find the simplest way to make sense of them (no need to complicate things in science, it's hard enough as it is (ref. above text on the meaning of words)), and have come to a conclusion there is a greenhouse effect (satellites give us the normal temperature in space this far from the sun), and that humans can increase the DWR (down-welling radiation) by adding insulation to the roof... oops meant to say CO2 in the atmosphere. I'm tempted to end this note to a thinly veiled
    insult to some people willing to lie and obfuscate this issue, instead I link to this: http://xkcd.com/54/
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  28. dana 1981 @26

    How do conclude that the imbalance is growing when it was about 0.9W/M2 and over the last 5-6 years is about 0.6W/sq.m?

    Are you talking about Ocean Heat Content instead?

    Eric @23

    A long term increase in imbalance - that is not what I concluded from Hansen's paper "Earth's Energy Imbalance and Implications" published in 2011. Please give me a link to any update on this if Hansen has changed his results recently.
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  29. Re post 28

    The latest version of the Hansen paper I can find is here:

    Earth’s energy imbalance and implications
    J. Hansen1,2, M. Sato1,2, P. Kharecha1,2, and K. von Schuckmann3 Published: 22 December 2011

    http://www.atmos-chem-phys.net/11/13421/2011/acp-11-13421-2011.pdf

    I would draw your attention to:

    Fig. 11. Observed and calculated planetary energy imbalance, smoothed with moving 6-yr trend.

    which clearly shows a declining overall global imbalance in recent years.
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  30. Tarcisio Jose D @ 19
    Thanks, Jose, for responding. I watched your clip. But for me this only highlights the problem. You see, I am not a scientist...you, Tom and Eric are engaging in a conversation that loses me. I could never begin to respond.
    But most importantly, you failed to answer the question I asked, so I will ask you:
    I understand you are a skeptic and you have data that backs your belief. What would change your mind? Is there anything in the data you show that might increase or decrease that would make you say, "You know, maybe I was wrong...maybe there is something to this AGW?"
    Or conversely, is your mind immovable?
    I am thinking you reflect the latter, but let me know if I am wrong. I did see on your youtube site the most recent clip titled "The Alarmist Inquisition."
    Are you really in an inquisition? I don't think so unless it is the Monty Python type with a fluffy pillow.
    I'm just asking a question, not putting you on the rack.
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  31. JimF @ 30

    Thank you for participating in this conference
    Your question should be answered thus: Nobody has the ability to change the thinking of someone else, only the person himself. What we do is meet the person of ideas that will change your thinking.
    As in the case of AGW.
    In 1861, John Tyndal released his study measured the "absorption" of infrared rays by atmospheric gases and hydrogen showed that even the "absorbed" or "dark heat" at a rate of 0.33% at a distance of 48 "(1.22 meters).
    Now think, if we calculate the attenuation caused by hydrogen own, the earth's surface to the center of mass of the atmosphere, 5Km high'll realize that a millionth part of the heat energy will reach this point. So our atmosphere is totally opaque to the "dark heat". No matter the quantity or the quality of gas that composes the atmosphere.
    Based on this reasoning had to show how our planet balances the energy flow and our film tries to show exactly this mechanism.

    http://tyndallconference2011.org/wp-content/uploads/2011/03/Tyndalls-1861-Lecture.pdf
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  32. Tarcisio Jose D @31, you continue to operate on an incorrect understanding of the green house effect. Specifically, the mechanism of the greenhouse effect is that the lower atmosphere absorbs infrared radiation from the warm surface, but the cold upper atmosphere emits IR radiation, half of which is radiated outwards, and hence leaves the Earth. The difference in energy intensity of the IR radiation from the surface and the IR radiation from the top of the atmosphere to space is the greenhouse effect.

    Applying this understanding, we examine your example of a grey atmosphere (one that absorbs equally at all IR wavelengths). In that case, increased GHG concentration will result in IR radiation from the surface being absorbed closer to the surface, but the absorbed energy will still be carried to the upper atmosphere by convection. However, the IR radiation to space will be emitted from higher in the atmosphere.

    This follows straightforwardly from the fact that the average altitude of emission to space will equal the average altitude of absorption of IR radiation in the same wavelengths from space. If increasing GHG concentration results in a shorter path to absorption for radiation from the surface, it will also result in a shorter path to absorption for IR radiation from space. Hence IR radiation from space will be absorbed higher in the atmosphere if we increase GHG concentrations. But then it follows that IR emission to space must also be from higher in the atmosphere.

    To a first approximation, however, higher is colder. Therefore with increased GHG, IR radiation to space will be from a colder layer of the atmosphere, and therefore emit less energy. The reduced energy emitted means that the greenhouse effect will be stronger with increased GHG.

    Of course, in the actual atmosphere, the stratosphere is warmer than the tropopause, so higher can be warmer. But in the actual atmosphere, not all IR frequencies are absorbed. Increased GHG strengthens the absorption on the edge of the absorption band, thereby increasing the effective altitude of radiation within the troposphere, and increasing the greenhouse effect. For a more detailed explanation, see here.

    I do not like this series of posts, for I am not sure that I am right. On the contrary, I continuously revise my beliefs in the light of new knowledge. But my core beliefs about AGW have simply not been challenged by so-called "skeptics" because they continuously present simplified models of the greenhouse effect, wrongly interpreted as being refutations of AGW. That they must resort to such specious arguments strongly suggests that while it is certain that some of my beliefs about AGW are false (if only I knew which), it is highly improbable that those false beliefs will be in fundamental aspects of the theory.

    As it stands, the evidence is overwhelming that those who understand the theory of the GHE accept it, while those who reject it (as Tarcisio does), clearly do not understand even the most basic features of the theory.
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  33. I'd like to add a few historical bits to what Tom wrote.

    First, I'm sure Tarciso didn't mean hydrogen as an absorbing gas. Indeed, Tyndall tried oxigen, nitrogen and hydrogen but reports a negative result, i.e. no absorption. Now we also know why.

    Tyndall would also have something to say on the saturation effect. In a Memoir published in 1872 he writes:

    "The acqueous vapour constitutes a local dam, by which the temperature at the earth's surface is deepened: the dam, however, finally overflows, and we give to space all that we receive from the sun"

    and Tyndall knew that water vapour is a stronger absorber than CO2. Following the same analogy, increasing absorption deepens the dam, i.e. increases temperature at the surface. This is in 1872 and it's not the full and correct explanation, but he was almost there.
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  34. Tom Curtis @ 32

    Very interesting theory.
    But .....
    I said, what the quality of its atmosphere makes it only absorbs IR radiation that rises in the atmosphere and free passes IR radiation that the atmosphere emits more toward the ground. I believe that there is this "rectifier diode" in our atmosphere and the greenhouse effect works both in one direction as another.
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  35. Tarcisio Jose D @31
    Sorry it took a bit to get back to you, but I was cutting back my candytufts a week before Mother's Day...I used to love those old pictures of Mom in front of the white blooms on Mother's Day.
    Jose, you've got to help me out here, because this how I start to get worried when I have these conversations.
    OK.
    For a non-scientific view, if in the year 2017 (five years from now), global land and sea temperatures continue to rise, 3 of those years land in the top 10 of warmest years on record, New Orleans gets hit with a category 5 AND Mexico gets hit with a category 5, Richard Lindzen has changed his mind, and JimF now cuts back his candytufts 3 weeks before Mother's Day rather than the current one or two, do you begin to question your stance on this?
    Is there any point that you say, "I still don't think that man is the primary cause to GW, but we add to it, and we need to start to do something about it?"
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  36. 34, Tarcisio José D,
    I believe that...
    Why do "skeptics" so often start sentences like this (usually followed by some perspective on the problem which is based on their own world experience, but completely unsupported by any true science)?

    Do you any evidence whatsoever to support your "rectifier diode" theory?

    Do you think there's some reason why perhaps no one else in the world has developed and supported your theory?
    0 0
  37. Sphaerica @36 and Tom Curtis @ 32

    Replay my post corrected.....
    Tom Curtis @ 32

    Very interesting theory.
    But .....
    My question is, which quality of your atmosphere makes it only absorbs IR radiation that rises in the atmosphere and free passes IR radiation that the atmosphere emits more toward the ground. I believe that there is'nt this "rectifier diode" in our atmosphere and the greenhouse effect works both in one direction as another.
    0 0
    Moderator Response: [Dikran Marsupial] Please can you supply a reference to a peer-reviewed scientific paper that suggests that GHGs only absorb IR radiation that rises in the atmosphere, a page number in the IPCC WG1 report will do fine. Unless you supply evidence that mainstream science makes such an assumption, I will assume that it is merely an attempt to disrupt the discussion. If you are unable to provide a reference, then this suggests that the problem lies with your understanding of the greenhouse effect. If you don't understand the greenhouse effect, then simply ask someone to explain it to you.
  38. Victull - "How do conclude that the imbalance is growing when it was about 0.9W/M2 and over the last 5-6 years is about 0.6W/sq.m?"

    Dana is likely referring to the long-term trend. Greenhouse gases, such as carbon dioxide, have a very long lifetime in the atmosphere, so the warming effect will be persistent and will grow over time as more fossil fuels are burnt. By contrast, the recent cooling effect imposed by natural (volcanic) and human-made aerosols, are short-lived and may not grow to match them. Additionally, despite the short-term fluctuations (as shown in figure 11 of Hansen [2011]), the global energy imbalance has undergone a long-term increase.

    SkS will be covering this in the near-future, as it's a source of confusion for many.
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  39. Tarcisio José D:

    How can I say this politely? Models of radiation transfer in the atmosphere do consider both upward- and downward-directed radiation, and the absorption/transmission/scattering/emission in both directions.

    Where on earth did you get the idea that they don't? Your ignorance is shining through like the headlight on an oncoming train. You really need to find some better sources of information.
    0 0
    Moderator Response: [Dikran Marsupial] Can I suggest that we ignore Tarcisio José D until he either posts a reference to a scientific paper that suggests the atmosphere does behave like a rectifier.
  40. Tarcisio Jose D. What I find so interesting is the statement:
    "I am very sure that I am right in saying that all who believe in the warming of our planet is caused by CO2 are totally wrong,"

    which then implies that you have chosen to believe a couple of video from dubious sources with laughable science over the bulk of known heavyweight physics.

    Now why would do such a strange thing? As you are finding out, things are more complicated than thought and the science is better, but why did you choose to trust such strange sources over known science. You claimed to be "very sure" which is also extraordinary. It would be really interesting if you could explain why you trust one source over another.

    As the "rectifier". DK, Bob, I dont think Jose is claiming the atmosphere works like a rectifer. He is trying to understand Tom and thinks that climate theory requires the atmosphere to behave like a rectifier because he hasnt understood the theory. This isnt that straightforward to follow. Eli Rabett did a good explanation I think but I cant find it. Any got a pointer?

    Jose, people are trying to make the greenhouse model explicable but ultimately the test is in doing the calculation. The real model with the equations can be found in Ramanathan and Coakley 1978. You need a computer to calculate the equations, but how do we know that is it right? Well because it predicts what we can observe of spectrum etc, with a very high degree of precision.
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  41. victull @28 - you're comparing different energy imbalance estimates. As I said, take a look at the Levitus post. Model-based estimates of a 0.9 W/m2 imbalance were probably over-estimates. We'll have more on this in the future.
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  42. Tarcisio José D @37, I have responded in detail on another, more appropriate thread, and suggest that you do likewise. I understand that you are using "Google translate" in order to overcome a language barrier. You are to be commended for your efforts to do so, but "Google translate" is not up to the task, and I recommend that you enlist the aid of a technically proficient, and bilingually fluent friend to aid you.

    In essence, my response points out that the atmosphere does in fact have the diode like property of emitting more radiation downward to the surface than it does upward to space (which my not be quite what Tarcisio meant by his use of the phrase), and that it has this property despite the fact that no individual component of the atmosphere has the property. I go on to point out that detailed modelling shows the property to exist, and that those models have been shown to be remarkably accurate by empirical observation, and that indeed that diode like quality of a higher downward IR radiation from the atmosphere than the upward IR radiation at the Top of the Atmosphere has been observed empirically.
    0 0
  43. (-Snip-)
    0 0
    Moderator Response:

    [DB] Please note that posting comments here at SkS is a privilege, not a right. This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators willfully submit offensive posts with direct accusations of dishonesty. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.

    Finally, please understand that moderation policies are not open for discussion. If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues may be in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.

  44. @Dragonwyst.
    excellent post. Your skill at observation and analysis of a situation gained from your nursing profession shines through. Only issue I would dispute is that there is no such thing as ‘only’ a nurse. All nurses are stars in their own right and have a lot to contribute to the methodology of climate science.
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  45. Hello friends.

    I went to thank @ 40 Scaddenp the link to "Ramanathan" I am studying It, with the application MODTRAN suggested by Tom and also to thank Tom Curtis the kindness of intervening in the discussion to progress of science. I must also say that the study of these two programs it appears that they are designed on the principle of transparency of the atmosphere to infrared radiation error this (Tyndall, 1861) obscured by the principle of irradiation of an isotropic radiator does not apply to this case.
    For these errors in the program it can not explain the behavior "diode like" presented bay the atmosphere and neither simulate the sensitivity to carbon dioxide.
    I'll find a Godfather to guide me in preparing the statements and try to overcome the barrier of the peer-reviewed. "
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  46. Tarciso
    "it appears that they are designed on the principle of transparency of the atmosphere to infrared radiation error"
    Absolutely wrong, they even quote the source of the absorption data.

    "the principle of irradiation of an isotropic radiator does not apply to this case."
    Wrong again, spontaneous emission is isotropic.
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  47. 45, Tarcisio José D,

    I think you should probably study the programs a lot more carefully before declaring them to be flawed.

    I promise you, if you think they are flawed, then there are things that you do not understand about them or the process.
    0 0
  48. Jose, when a program is able to correctly predict observed spectra to very high precision for earth and other planets, I would be very hesitant to declare it is wrong, you would have to ask yourself whether the program (and thus the underlying model) is wrong - or your understanding of it. I'd say study Ramanathan more closely. You do understand why GHG effect depends on lapse rate? Ie no GHG effect in an isothermal slab.
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  49. Jose, I am still curious as to why you chose to trust a couple of dubious videos instead of textbook atmospheric physics. Both speak to something that is new to you, so why did you trust one rather than the other?
    0 0
  50. Ricardo @ 46

    An emission, spontaneously or not, must be analyzed by the principle of isotropic radiation when the distance between the points of transmission and reception (measured) is greater than 10 times the largest dimension of the radiator. Our radiator has 20,000 km long (equatorial) therefore can not be analyzed in a distance of 10 Km as an isotropic point.
    0 0

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