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Comments 91401 to 91450:

  1. Why we have a scientific consensus on climate change
    moderator : I know that this will be soon censored, but this is kind of a private conversation : how can you honestly defend the opinion that the science is proved, if even their best defenders implicitly say the opposite ? and how can you claim that you defend honestly science , if you're not even able to let this question appear and answer it easily ?
    Moderator Response: [Dikran Marsupial] Nowhere have I sais the science is proved, in fact I explicitly said that such proof is fundamentally impossible "You can't prove a theory regarding the real world, only disprove (Popper)". Perhaps you need to read what is written in replies to your posts more carefully (on that topic, your recent comment implies that the 97% consensus is unusual, when if you read the article, it explicitly states that it is not unusual - read the last paragraph). BTW if you want to have a private discussion, email would be a better option, my email address is dikranmarsupial@gmail.com .
  2. Why we have a scientific consensus on climate change
    @22 LazyTeen (is there another kind?): Yes. Consensus is a consequence of solid evidence and hypothesis/theory, not a proof of it. To the standard "skeptic" strawman "Consensus is not proof," part of my resposne is often something along the lines of "No, consensus isn't proof, and no one says otherwise, but it is evidence of evidence."
  3. Why we have a scientific consensus on climate change
    so what do you understand from : "From my own experience, such a high proportion is quite unusual." which "experience" is he talking about ? a tautology is not "unusual" , usually ...
    Moderator Response: [Dikran Marsupial] As I said, it would only be unusual if the claims against the consensus view were credible. If such claims were credible it would be unusual as the divisive nature of scientists would prevent such a large consensus if there actually were grounds for division. However, the substantive point is that there is a general (if not complete) consensus, so please move on to a discussion on the substantive issue, rather than quibbling irrelevant details.
  4. 2nd law of thermodynamics contradicts greenhouse theory
    Re #782 scaddenp you wrote:- "still waiting to hear whether you accept that experiment is way to settle the debate." Not at all sure what experiment you have in mind. Care to describe it?
    Moderator Response: [DB] The question here, which you have conspicuously avoided answering for some time now, makes it clear that the experiment design to prove your alternative world of physics is up to you. We're still waiting.
  5. The True Cost of Coal Power
    BTW, Gilles, your data regarding Germany's per capita CO2 emissions is almost 4 years old. Back in 1991-before they embarked on their renewable energy & energy efficiency program, their emissions were 12t per capita-so a 3.4t per capita reduction in the space of 15 years-with no apparent harm to GDP growth (per capita GDP of around $41,000). The US, btw, that has double the CO2 emissions (per capita) of Germany has a per capita GDP of only $47,000. Denmark, Sweden & Norway also have significantly lower per capita emissions than the US, yet their per capita GDP is *higher* than the US ($55,000, $49,000 & $88,000 respectively). The UK & France have *also* reduced their CO2 emissions-by around 1t per capita from 1991 levels-& they also have very good per capita GDP ($36,000 & $39,000 respectively) really kind of puts paid to the whole Fossil Fuel use=greater wealth argument. Anyway, like I said, I'll now leave you to dwell in your fantasy land. Just please stop spamming your fantasy around this site *unless* you have some kind of solid proof to back it up.
  6. Why we have a scientific consensus on climate change
    It's a standard climate skeptic debating point to express contempt for a "consensus of climate scientists". My standard answer to this is that it is not just a consensus of points of view. It is much stronger than that. It is really a "consensus of evidence".
  7. Why we have a scientific consensus on climate change
    19 Philippe : maybe you can give a constructive opinion of why a 97 % agreement is considered as "unusual" , for a proven theory ?
    Moderator Response: [Dikran Marsupial] You can't prove a theory regarding the real world, only disprove (Popper), so your question is based on a fundamental misunderstanding. Taking that into account, the question becomes "why is a 97% agreement considered as "unusual" for a generally accepted theory?" then the question is merely a tautology posed as a question. As the article suggests, scientists pick holes in theories for a living, so 97% consensus would be unusual if the generally accepted view didn't have good support from the theory, experiment and observation. Thus the 97% consensus would be unusual only if the skeptic objections were as solid as presented on e.g. skeptic blogs. In my view, it isn't unsual.
  8. 2nd law of thermodynamics contradicts greenhouse theory
    Damorbel - still waiting to hear whether you accept that experiment is way to settle the debate. Sounds like you only want to talk, not find anything out.
  9. Why we have a scientific consensus on climate change
    rhjames: check the link you were first given! The 97% was originally from a small sub-section of those polled by Doran & Zimmerman for a 2009 paper. Anderegg, 2011 found about the same figure using different methodology, as explained in the post.
  10. Philippe Chantreau at 19:27 PM on 23 March 2011
    Why we have a scientific consensus on climate change
    Gilles complains of a question too vague and ends his post with an accusation that is even more so, although what he hints at is the usual stuff. Yes, Gilles, you may offer an explanation. None of the word salad above qualifies as such.
  11. Those who contribute the least greenhouse gases will be most impacted by climate change
    "One of those options is to choose, really choose, to 'develop' at a rate that can be supported by renewables only. It might be slower than you or I might prefer, but it is still development. " why do you think it would be slower, after all, if the capacities are the same ? the only thing to do is to built power plants, after all. What limits the rate of annual growth of electricity production, following you ? and how do you explain that "far better " solutions aren't adopted by anybody , and that they absolutely refuse to sign anything constraining their absolute CO2 production (which is usually considered as "understandable" in international discussions)? BTW, chinese politicians do not seem to have a strong aversion against renewable hydroelectricity. So why don't they produce everything with renewable energies, if they accept water? do you think there is a strange mental disease leading to like electrons from water and to dislike electrons from wind and sun ?
  12. Why we have a scientific consensus on climate change
    so : " 97 out of 100 agree that the climate is changing and that we are causing it." May I offer an explanation of this "quite unusual " proportion? that the question is so vague that it is difficult to say "no". What is "changing" ? climate ? well I do not know anybody who lived 30 years ago in tropical, temperate, or Arctic zones and who has changed the name of its climatic zone ! The north of France is always rather cool and rainy and Mediterranée is always a marvelous see. So "climate" in the original meaning hasn't changed for anybody - scientists may have thought that "average surface temperature " has changed - but that cannot be contested. It has changed, that is only intrumental measurements. And that we "are causing" it ? well may be - there must be some anthropic changes. Even big dams change climatic conditions (although not enough to change the overall qualification , as I said). Deforestation, change of land use, urbanization all change the local precipitations and temperature. And of course CO2 is contributing. So it is almost impossible to answer "no, we aren't changing anything". But the given explanations are somewhat strange : "From my own experience, such a high proportion is quite unusual. ... So how come that 97 % of the experts agree that the current warming is not natural but a consequence of burning fossil fuels? First, it is because all our data show that the global mean temperature is increasing, that the glaciers and the arctic ice are melting and therefore sea levels are rising." So the question is about the cause of the change, and the justification is "because it is observed"? I don't really understand the relevance of the explanation. "Second, we know that burning fossil fuel releases CO2 into the atmosphere. Nowadays we know how much CO2 we put into the atmosphere by using it as our global garbage bin for fossil fuel. All our climate observations show a global increase in temperature. This increase is consistent with the well established properties of CO2." another strange formulation : we explain that 97 % (an "unusual proportion" ) of scientists do agree by the fact that the increase is "consistent" with ? (notwithstanding the fact that the main issue is that of retroaction, not the primary IR absorption?) Well it is not "unusual" that a very large majority of scientists accept theories : special or even general relativity, quantum mechanics, and biological evolution is probably accepted by a still larger proportion of scientists. So why does the post qualify this proportion as "unusual"? probably because the given reason ("consistent with") is usually considered as "weak evidence" and not "definitive proof". The "unusual" thing is that so many scientist agree on so weak evidence (not simply that "so many scientists agree").if they were definitive proof of the purely anthropogenic evidence, this would not be unusual : this would be normal. But the post does not really offer an explanation of why. May I offer an explanation : that other things than scientific considerations interfere with the answer.
  13. 2nd law of thermodynamics contradicts greenhouse theory
    Re #780 it has :- "an average temperature of about 279K, an average taken over the entire planet - summer and winter; pole to pole." And of course, 'day and night'.
  14. Why we have a scientific consensus on climate change
    rhjames at 5:18 reckons -------- You mentioned retired engineers and physicists. Perhaps they are the ones who have time to go into detail, and make informed judgments, rather than follow the popular trend. -------- The overall position of this demographic is not known. However the noisy ones commenting in climate skeptic blogs follow a pattern: 1. Claims that "I am smart and climate scientists are stupid" 2. Followed by some comment proving they are incompetent in their own technical field.
  15. 2nd law of thermodynamics contradicts greenhouse theory
    Re 769 RW1damorbel (RE: 755), ""And why the 'GH' effect is not a radiation effect... from... GH gases." OK, then what is the primary mechanism for the greenhouse effect?" Since the GHE is an explained as a radiation effect t "No amount of refocussing ...... Or, in other words, increase the temperature of.... anything. That is what the 2nd law is all about." #Responding you say:- "The second law primarily states that heat can only flow from warm to cold - not the other way around." Yes However, you say also:- ".. the rate the incoming energy can leave the system from the surface is slower than the rate it is coming into the surface." Most GHE explanations say that this 'slowing' is because of a warming effect on the surface by radiation from GH gases in the atmosphere. Since the atmosphere is colder than the surface any radiation from it will not warm the surface because its photons do not have the energy to do this. What does happen is, photons from the surface, having more energy than photons in the upper atmosphere warm it, the heat thus transferred upwards is re-radiated (by GHGs) into deep space, keeping them cool. Do you agree? Then you write:- "The effect in principle is not much different than the interior of a car heating up inside on cold day from sitting out in the Sun. The Sun's energy is mostly transparent through the windows. It's then absorbed and re-radiated by the interior car components. The rate at which the energy is entering the interior is faster than the rate the re-radiated energy can leave the interior; therefore, the interior has to heat up." What you say doesn't just apply to a car, it is the same for a greenhouse or any surface exposed directly to the Sun's output. It's well known that, in a desert, the Sun can heat a surface well above 100C, enough to fry an egg. But even the arguments for the GH effect agree that it is the average temperature that is inportant, so they account for this by saying the Sun's output (the solar constant ) is not the measured 1370W/m^2 (@5780K if they include the temperature of the photons) but 342.5W/m^2 this latter would give an average temperature of about 279K, an average taken over the entire planet - summer and winter; pole to pole. Further you have:- "Ultimately, when the rate of energy entering something is faster than rate it can leave, the something has to heat up. That's the GHE." Couldn't agree more. Are you able to say at what temperature this would stop, if at all? The only beef I have with the arguments for the existance of the GHE is that it is not supported by well established thermal physics, like focussing photons increases their energy, simply not true. If it were true mirrors would change the colour of light when they reflect it; now that would be strange!
    Moderator Response:

    [DB] "The only beef I have with the arguments for the existance of the GHE is that it is not supported by well established thermal physics"

    Then you haven't been paying attention, clearly. Read the whole post, starting at the beginning. The comments too, if necessary.

  16. Pre-1940 Warming Causes and Logic
    "This post is a rebuttal to the "skeptic" myth that the pre-1940 warming was purely natural, and as large as the current warming, thus the current warming could also be natural. The article refuted all three of these points." I think that what people like Humanityrules and myself try to tell you is that presenting a possible, unproved, combination of explanation is not a rebuttal and doesn't refute other possible combinations. Before excluding possibilities, you must have solid evidence to exclude them - which is not the case here.
  17. Pre-1940 Warming Causes and Logic
    dana it seems that you distort somewhat the numbers. If the warming rate is 1.3°C /century during the 1910-1940 period, this makes a total 0.4 °C. Fig 1 shows that anthropogenic influence is estimated to be around 0.1 °C, and Fig 5 shows around 0.2 °C for natural forcings (BTW in Fig 4, I think the text should be corrected, it says " Simlar to the anthropogenic contribution, the best estimate of the anthropogenic contribution to the 1910-1940 warming in Meehl (2004) is approximately 0.1 to 0.15°C " - you meant probably solar forcings) for natural forcing. You don't plot the sum of the two, but I guess you have some difficulties to explain the whole variation. And there is absolutely nothing that explains naturally the break around 1940 - nothing changes up to the Agung explosion in 1963. So the whole picture looks much more like a approximate estimate of largely unknown contributions : "expected to be 0.22 °C but due to ocean lag and other anthropogenic effects it should be between 0.1 and 0.15 ° C" : well may be but that's very far from a precise theory ! why wouldn't ocean lags and other anthropogenic effects wouldn't limit rather the warming to 0.05 ° C , leaving 0.15 °C unexplained ? can you prove that it is impossible ? this is by no way an exclusion of the other possibilities , which is the real criterion of validity of a scientific theory. What you're offering here is a possible combination of influences, neither of them being precisely determined - and this combination doesn't fit very precisely the shape of the curve. You may find me too critical, that it is impossible that scientists would try to disguise the uncertainties and be dishonest. Then tell me, who said : "The Figure you sent is very deceptive. As an example, historical runs with PCM look as though they match observations -- but the match is a fluke. PCM has no indirect aerosol forcing and a low climate sensitivity -- compensating errors. In my (perhaps too harsh) view, there have been a number of dishonest presentations of model results by individual authors and by IPCC. " doesn't it prove that you can indeed reproduce data with wrong models ?
  18. Philippe Chantreau at 17:41 PM on 23 March 2011
    2nd law of thermodynamics contradicts greenhouse theory
    Nonsense and more obfuscation. Your accusation would be somewhat insulting if I cared the least about your opinion. If you want to debate atmospheric physics that are obvious to all researchers in the field, you should take it to the peer-reviewed litterature. I'll be very curious to see how your first paper looks like. What you are trying to argue about is no more a matter of debate than protein encoding by DNA. I have seen nothing of value for any kind of debate in the tediousness with which you have drowned this thread.
  19. Why we have a scientific consensus on climate change
    Normal # 1 The main claim your link makes is that theres been no warming over the last 15 years. The data you provide is for 9 years, is selective and deceptive, and shows a slight warming trend anyway. Some of it also looks fraudulent to me but Ill give you the benefit of the doubt there, but appreciate Im very, very sharp. Since you seem determined to quote nonsense, I wont bother furthur.
  20. Why we have a scientific consensus on climate change
    This is a call for more rigour in "case making": 1. The term "consensus science" is an oxymoron - at least if you do your science a la Popper. If you DON'T do your science a la Popper then by all means feel free to add whatever terms you wish to what you call "Science". "Real" Science ONLY deals with trying to know more by attempting to disprove what we think we already know. Holy huddles don't count. New advances in any discipline almost invariably come from outside the self congratulatory back slapping in-crowd. 2. It may well be that Dr Stemler does a good job in his broadcast of addressing the issues raised. I hope to listen but time does not yet allow. BUT the short piece above does a very poor job of making a good case, which is a shame - all material on such an important matter that is intended to sway the less or un convinced should be carefully thought out. Otherwise you are just preaching to the choir, or taunting the lions (as I am probably doing here :-).) 1. The paragraph above starting "First ..." is neutral with respect to the point being argued, and so essentially pointless. 2. The paragraph starting "nowadays" is questioned by vanishingly few of any persuasion and is not germane to making the desired point. 3. The paragraph starting "Second ..." is close to information free as the issue for a very large majority of all persuasions is not the well understood basic thermal behaviour of gases but the magnitude of the multiplying factors caused by feedbacks - "forcing" in the jargon of the day. There are other secondary factors which merit discussion, but if the pertinence of an argument to the above points is not made clear in a summary, then others than the choir may wonder if it's going to be worth listening to he podcast. Russell McMahon apptechnz@gmail.com
  21. 2nd law of thermodynamics contradicts greenhouse theory
    Philippe Chantreau "Most readers who are unfamiliar with the physics would only take away the impression that this is a matter of debate and their perception of the whole process might be totally confused. Obfuscation is not useful to anyone" Said otherwise: Quick kill the debate! Uncomfortable points of contention must not be seen! Back tomorrow, if this thread is still open.
    Moderator Response:

    [DB] Despite handwaving implications to the contrary, the existence and length of this thread is mute testimony to the tolerance of non-physical points of contention. On-topic comments constructed to comply with the Comments Policy go unmoderated, as the vast majority of readership here at Skeptical Science can attest.

    You have yet to demonstrate the physical-ness of your position, as other participants have pointed out to you several times.

  22. Why we have a scientific consensus on climate change
    KR at 15:33 PM,re "I will note that some circulatory patterns, such as the Indian Ocean Dipole (IOD), do appear to be settling into one state as a result of climate change." What causes you to arrive at that conclusion, particularly with regards to the IOD, but also generally for those other systems that apparently appear to be settling into one state?
  23. Zero Carbon Australia: We can do it
    I think that this as a fantastic idea and I am right behind it. I do however need one last bit of convincing that it is possible. A final tick of approval for the plan if you will. Where are you going to get the raw materials, more specifically the rare earths. For every MW of wind electricity generated you require 1 ton of Neodymium. 90% of this mineral is mined in China and due to its advanced renewable energy projects they are not sharing anymore. Australia mine no neodymium until the mines at Mt Weld and Nolans bore are up to speed. Even then they will not produce enough. The whole world produces about 28,000 tons of this element a year (hence the term rare earth I guess). We would need a significant portion of the worlds supply to achieve these targets and even then there is the not sharing anymore issue. That is just one element. Add to the list Lanthanum and Yttrium and a host of others used in solar and reflective glass and electricity storage. Should we be fighting against the Greens and fast tracking rare earth mining project? Will we have enough?
  24. Why we have a scientific consensus on climate change
    To say Tyndale's "pioneering work eventually inspired physicists to develop the theory of quantum mechanics" sounds like quite the overstatement. His name is not even mentioned in any of the short works I have read on the history of QM. Other than that, this podcast looks quite good.
  25. Pre-1940 Warming Causes and Logic
    57+58HR, Thank you for the link, but the first link is to the Schrijver et al paper, not the review you mentioned. I have no problem with the downward revision of short term TSI variability because it is small to begin with. The variation in TSI through a 11 year cycle is about 1W/m^2 (at least we can say this with some certainty), which translates to about 0.1 degrees of change, so I think whether the difference from MM to current is 1w/m^2 or 0.1 w/m^2 is essentially immaterial in the grand scheme of things, simply because 1w/m^2 is small compared to the error bars, not only for the temperature record but compared to the uncertainties in the other forcing factors. Putting it in perspective, the projected increase in temperature is anywhere from 2 to 4 degrees over the next century. How significant will 0.1 degrees change due to the revision be? The sun plays an important role in our climate when the orbital changes causes 1% to 10% change in the TSI, if the 10 fold correction happens here then yes there is a need to rethink the whole picture. regarding the AMO. I don't see it mentioned anywhere in the paper. Then again the gap between the observed and forcing account for is about 0.1 or 0.2 ignoring solar.
  26. Steven Sullivan at 15:39 PM on 23 March 2011
    Why we have a scientific consensus on climate change
    If rhjhames was following climate science literature closely at all, he'd already know about Anderegg et al., it made quite a splash last year. I'm a scientist (biologist) who follows climate matters and I read about it, and even downloaded and read it. If he wanted to get close to the original data he'd have done that too. So I question how closely he's actually following the literature, and I wonder what kind of scientist he is.
  27. Philippe Chantreau at 15:37 PM on 23 March 2011
    2nd law of thermodynamics contradicts greenhouse theory
    John and moderators, I agree. Despite DSL's point (valid to an extent), I can not see how allowing the same obfuscation again and again adds anything. Most readers who are unfamiliar with the physics would only take away the impression that this is a matter of debate and their perception of the whole process might be totally confused. Obfuscation is not useful to anyone.
  28. Zero Carbon Australia: We can do it
    ( - numerous rantings violating the Comments Policy en masse snipped- )
    Moderator Response: [DB] Posting on this site is a privilege, not a right. Future postings such as this one may have that privilege rescinded. Be advised.
  29. Why we have a scientific consensus on climate change
    Norman - That's quite a Gish Gallup; a collection of half-truths, falsehoods, and misrepresentations. Here's a repeat of what I posted on a 'skeptic' site in this regard: 1) Warming is said to be unprecedented and accelerating. It is neither. See It's not happening, Pre-1940 Warming Causes and Logic - We're warming pretty fast, driven by CO2, the changing levels of which are unprecedented. We're heading for a very high interglacial temperature the likes of which we haven't seen since the peak of the Holocene, if not higher. And warming is definitely accelerating. 2) Global warming is not GLOBAL. Uh, what!? Every record shows global warming. See It's not happening. This is utter bull - warming is faster in the Northern hemisphere, but it's global and it's happening. 3) Winters would grow increasingly warm. 4) The entire Northern Hemisphere would experience less snow and snowcover Globally, yes. Locally, in some regions, the relatively warmer Arctic is pushing the jet stream south, and some regions are seeing more peak snowfall. But winters are shorter, spring arrives earlier, fall stays later, and crops and flowers bloom earlier. Definitely happening. 5) Increasingly positive AO I'll let others speak to this - I hadn't heard that this was a consensus opinion. 6) Global warming may lead to a permanent or semi-permanent El Nino Again, I don't believe this was a consensus opinion. If not, both this and #5 are strawman arguments. I will note that some circulatory patterns, such as the Indian Ocean Dipole (IOD), do appear to be settling into one state as a result of climate change. 7) Atmosphere will warm faster than surface (because that is where the heat trapping gases are). This appears to be a variant of the "Hot spot" argument. See There's no tropospheric hot spot. Observations match models and physical predictions, although old data (poorly calibrated) may have indicated otherwise before corrections. 8) Record highs and heat waves are increasing Record high temperatures versus record lows 9) Sea levels are rising at an increasing rate See: Sea level rise is exaggerated, Sea level rise predictions are exaggerated. The ARGO floats versus older XBT data are still rather contentious, as calibration of the XBT's is, well, poor. There is ongoing work here, but so far, the data doesn't contradict predictions or theory. 10) Droughts and floods will worsen in places like Australia So far, the data appears to support this. More is needed, and in the next 10-15 years I expect that the data will reach statistical significance. It may have already; I'll leave it to others in that regard. --- So, Norman, this link of yours is not supportable as criticism of AGW. You have obviously not used the 'Search' link on this site, or you would have seen multiple replies in that regard. Why did you post this link?
  30. Philippe Chantreau at 15:28 PM on 23 March 2011
    Why we have a scientific consensus on climate change
    I note in the link provided by Norman that D'Aleo or whomever else concocts a graph of winter temps in some region over 9 years and makes it a "trend." In another one they look at temp at the 100 to 300 mb level and label that as "mid troposphere." That's really kinda funny considering that the 100 mb level is around 53 000 ft. Some mid level that is. I spent about 30 seconds on the site to pick up these 2 screamers. Sorry Norman, I'm not a scientist but I know when someone is trying to fool me. The red flags at D'Aleo's are all over the place, so many of them that one can hardly see any data.
  31. 2nd law of thermodynamics contradicts greenhouse theory
    But Daniel, the thread has been instructive. Pretty much every kind of wiggle imaginable has been attempted. If anyone who has any doubt about GHGs and the 2nd law after reading the entirety of this thread, they should get some sleep and try it again in the morning. Or perhaps try a more thorough explanation of a pretty simple physical interaction.
    Moderator Response:

    [DB] Anyone with the willpower to read the entirety of this thread has a cast-iron stomach and a thing for pain. Maybe that's why I'm a mod. :)

    It should be painfully obvious by now that all that is being offered up are permutations of permutations (ad nauseum) of debunked and rebunked arguments.

  32. Why we have a scientific consensus on climate change
    rhjames @ 7: have a read of the article linked by the moderator in post #1. It answers your questions as to what was asked & by whom.
  33. Why we have a scientific consensus on climate change
    Further to Sphaerica's post, I'm an engineer (not yet retired, and hopefully not grumpy!). A mechanical engineer at that, so I have a fair bit of eduction in and understanding of heat transfer. I've been reading a *lot* of scientific papers & articles on climate change over the past five years or so. One thing I've noticed (which most of us on this site have noticed) is that the "it's not happening" arguments are remarkable, in the sense that there is no substantial, scientifically verifiable evidence for them. None at all. Contrast that with the view that it is happening, where you have literally gigabytes (probably terabytes, actually) of supporting data, and thousands of pages of scientific analysis that either directly confirms the human-caused global warming hypothesis, or does not contradict it in any way. That's not to say that we know everything about global warming - it's a rich field of research, with scientists learning something new every day. There are many areas of dispute as to exactly how the extra heat trapped by greenhouse gases affects the planetary climate, and the nature & extent of the various feedback mechanisms. But the fundamental question as to whether CO2-driven global warming exists has long since been answered in the affirmative. Unfortunately for us, the more scientists learn, the worse it looks. :-( One last point: I have to say, I'm continually puzzled how anyone with university-level education in heat transfer can deny the existence of the greenhouse effect. But then I remind myself that some of my fellow students really struggled through, barely passing subjects on the back of rote learning with little real comprehension. That might explain some of it, perhaps.
  34. Why we have a scientific consensus on climate change
    Sphaerica - I've been looking at climate change literature for the past 10 years. Where possible I get as close to original data as possible. I follow sea level, CO2 etc trends around the world. I don't take anything at face value, and I'm prepared to ask the hard questions. I've read much of the literature on this site. So, I don't just take the claims of this article at face value. I want to know the questions asked, the answers given, and who these scientists are. I've investigated this sort of detail before in surveys, with very disturbing findings. You mentioned retired engineers and physicists. Perhaps they are the ones who have time to go into detail, and make informed judgments, rather than follow the popular trend. My question remains - what were the exact questions asked of these scientists, and who were they?
  35. Daniel Bailey at 15:12 PM on 23 March 2011
    Arctic sea ice has recovered
    The melt? Or the Plunge?
  36. Arctic sea ice has recovered
    I did - I didn't want to mention it. Too depressing.
  37. Why we have a scientific consensus on climate change
    I believe the study Dr. Stemler is citing is Expert Credibility in Climate Change by William R. L. Anderegg et al. published in the Proceedings of the National Academy of Science found here: http://www.pnas.org/content/early/2010/06/22/1003187107.abstract The scientists discussed in the study all self-identified in one way or other as accepting or rejecting the scientific consensus, for instance by signing petitions and so on.
    Moderator Response: [DB] Hot-linked URL.
  38. Why we have a scientific consensus on climate change
    rhymes,
    I've seen no real evidence to support this hypothesis...
    Then you haven't looked. Shame on you. This site is crawling with evidence (unless you simply refuse to see it).
    Computer models, yet to be substantiated by real data, are nothing more than interesting.
    False. 100% false. First, the computer models are more than "interesting" and have real value. But beyond this, evidence from a very wide variety of observations supports both warming and an anthropogenic cause. Claiming that you are right because you yourself are ignorant of the facts is hardly an argument.
    I know of many scientists that are yet to be convinced that anthropogenic warming is any more than unsubstantiated theory.
    Yes, but climate scientists? Or just people who are arrogant enough to think they're smart enough to be experts in any field of expertise, when they clearly are not? The world is crawling with retired physicists and engineers who will dispute global warming. I don't know why, but it's endemic. Every grumpy old man with a college degree and a career in the sciences (but not climate science) seems to want to angrily deny global warming. The fact that they do is hardly a weighty argument. Let me see, who should I trust? Thousands of climate scientists, actively working in the field, or a bunch of retired physicists and engineers who think they know better than everyone else, have little care for the future, and yet have repeatedly, over the course of the past decade, failed to substantively counter the data and logic which demonstrate the truth behind global warming?
  39. Why we have a scientific consensus on climate change
    D'aleo AND icecap. Really. Now, any point on that "challenge" not already debunked here? Why do you go such sources when you can easily see the content is rubbish? A real challenge to consensus science would be in the form of peer-reviewed publication.
  40. Why we have a scientific consensus on climate change
    Norman, What is your challenge? The documents you provide are primarily just a litany of the same old, tired and false skeptic arguments, all of which are easily debunked in various parts of this site. There's little point to even looking at them. But more importantly, I couldn't find a single reference to refute the 97% consensus argument. What exactly is your point? That you are right, and your documents prove it, therefore 97% of climate scientists couldn't possibly agree with you? Personally, I think your post amounts to nothing more than off-topic trolling and should be deleted.
  41. Why we have a scientific consensus on climate change
    I'd like to know the question that was asked of these scientists. I'm a scientist (not involved in climate), and if I'm asked if I believe humans influence the climate, my answer is yes. If I'm asked if the net result is warming or cooling, my answer is "I don't know". If I'm asked if I believe that human activity will cause catastrophic (or even significant)warming in the next 100 years, my answer is that I've seen no real evidence to support this hypothesis. Computer models, yet to be substantiated by real data, are nothing more than interesting. My point is that scientists are trained to be very exacting. The question has to be very specific. So show me the actual questions that were asked. I know of many scientists that are yet to be convinced that anthropogenic warming is any more than unsubstantiated theory.
  42. Why we have a scientific consensus on climate change
    Here is a challenge to the consensus argument. Plenty of graphs and data that show things may not be as certain as the 97% claim. Part One. Part Two.
    Moderator Response:

    [DB] To get a proper perspective, you should read this.

  43. 2nd law of thermodynamics contradicts greenhouse theory
    Sorry to break this into multiple posts - it's late and I'm tired. L.J. Ryan - Incoming energy is set by spectral absorptivity, albedo, and the spectra of the sun in visible light. Greenhouse gases have little effect on that - the most important elements there are ozone absorption and Rayleigh scattering. Given a fixed input energy, the black body temperature represents a minimum temperature for the radiating gray body, the Earth. Any lowering of emissivity (such as increasing greenhouse gases) must be balanced by an increase in temperature above that of the black body case to match input power.
  44. Pre-1940 Warming Causes and Logic
    HR - I agree climate sensitivity is what matters. But that's not the issue here.
  45. 2nd law of thermodynamics contradicts greenhouse theory
    L.J. Ryan - From your reference: "That a perfectly absorptive ("black") body rises to a temperature a bit higher than an actual black body that’s free to radiate to its surroundings. A theoretical blackbody thereby defines the upper limit of temperature vs radiant absorption." And there is the error. The Earth is not a black body, but is a "gray body" with ~60% the emissive efficiency of a black body. And hence a higher temperature than a perfectly efficient black body radiator. Your reference is in quite serious error to argue against the greenhouse effect in these terms - it's a rather horrid miscasting of the situation. It's only an upper limit for a black body - anything with a lower emissivity will by necessity have a higher temperature for the same power output. I would not trust that source, given the example you presented.
  46. 2nd law of thermodynamics contradicts greenhouse theory
    L.J. Ryan - Blackbody temperature is important as a theoretic limit. However, the Earth in the real universe is not a blackbody. The Stefan-Boltzmann relationship holds for the Earth, and the power radiated to space (which must match power coming in for dynamic equilibrium) is determined by both the temperature and the emissivity of the planet. Any body that is not a blackbody (with an emissivity < 1.0) must have a higher temperature to radiate the same power as that blackbody. The blackbody is the theoretic best case; everything else is less efficient. With an effective (surface to space) emissivity of 0.612, including clouds, GHG's, tropospheric effects, lapse rates, etc., a surface temp of ~287 radiates ~239 W/m^2 to space, almost equal to the sunlight coming in. The difference of 0.9 W/m^2 is the forcing, heating the climate and moving back towards dynamic equilibrium. So - you are incorrect because the Earth is not a blackbody. It has a limited emissivity to space, and the resulting temperature needed to radiate 240 W/m^2 is around 14-15C.
  47. Arctic sea ice has recovered
    Anybody notice Arctic sea ice extent topping out for the winter season? -- JAXA Per their text file, the maximum extent was March 8. The Melt begins ...
  48. Philippe Chantreau at 14:16 PM on 23 March 2011
    2nd law of thermodynamics contradicts greenhouse theory
    "how does a body at 255K which is loosing heat increase it's temperature simply by slowing it's cooling....remember blackbody temperature is the theoretical maximum temp." Considering that the body in question is continuously receiving energy at a more or less constant rate, it does not seem so difficult to imagine that its temperature will increase if the rate at which it can radiate that energy is decreased. In fact, I would have a hard time to understand if it did not warm up under these conditions.
  49. Understanding Solar Evolution Pt. 1
    garythompson, A good point, but I'd stress that CO2 is a big player in past climate, and there's no reason it cannot generate a large greenhouse effect. The key suggestion that the Sagan paper made was that Ammonia was a plausible greenhouse gas that could help rectify the faint sun problem, but it was later shown that this would be photochemically unstable in the atmosphere (e.g., Kuhn and Atreya, 1979). Although they were wrong, it is a great paper that paved way for an enormous amount of research...just how science should be.
  50. 2nd law of thermodynamics contradicts greenhouse theory
    KR, John Cook, Tom Curtis Please explain why, seriously, why Kirchhoff's cavity experiment does not represent the theoretical BB maximum temp. I realize it doesn't explain the 33K delta but why is wrong? Maybe your superior physics can explain how BB maximums should be determined. Don't insult me or say I'm wrong without explanation of what is wrong.

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