Recent Comments

Prev  1825  1826  1827  1828  1829  1830  1831  1832  1833  1834  1835  1836  1837  1838  1839  1840  Next

Comments 91601 to 91650:

91601. 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.
91602. Gilles at 18:56 PM on 23 March 2011
       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 ?
91603. Gilles at 18:30 PM on 23 March 2011
       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.
91604. damorbel at 18:21 PM on 23 March 2011
       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'.
91605. LazyTeenager at 18:15 PM on 23 March 2011
       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.
91606. damorbel at 18:00 PM on 23 March 2011
       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.

91607. Gilles at 17:50 PM on 23 March 2011
       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.
91608. Gilles at 17:44 PM on 23 March 2011
       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 ?
91609. 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.
91610. nigelj at 17:22 PM on 23 March 2011
       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.
91611. SME at 16:42 PM on 23 March 2011
       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
91612. L.J. Ryan at 16:23 PM on 23 March 2011
       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.

91613. johnd at 16:08 PM on 23 March 2011
       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?
91614. Vague at 16:03 PM on 23 March 2011
       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?
91615. MattJ at 15:50 PM on 23 March 2011
       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.
91616. IanC at 15:43 PM on 23 March 2011
       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.
91617. 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.
91618. 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.
91619. h pierce at 15:37 PM on 23 March 2011
       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.
91620. KR at 15:33 PM on 23 March 2011
       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?
91621. 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.
91622. DSL at 15:23 PM on 23 March 2011
       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.

91623. Bern at 15:22 PM on 23 March 2011
       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.
91624. Bern at 15:19 PM on 23 March 2011
       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.
91625. rhjames at 15:18 PM on 23 March 2011
       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?
91626. Daniel Bailey at 15:12 PM on 23 March 2011
       Arctic sea ice has recovered
       The melt? Or the Plunge?
91627. DSL at 15:10 PM on 23 March 2011
       Arctic sea ice has recovered
       I did - I didn't want to mention it. Too depressing.
91628. FatherTheo at 15:09 PM on 23 March 2011
       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.
91629. Bob Lacatena at 15:03 PM on 23 March 2011
       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?
91630. scaddenp at 14:58 PM on 23 March 2011
       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.
91631. Bob Lacatena at 14:56 PM on 23 March 2011
       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.
91632. rhjames at 14:51 PM on 23 March 2011
       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.
91633. Norman at 14:41 PM on 23 March 2011
       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.

91634. KR at 14:40 PM on 23 March 2011
       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.
91635. dana1981 at 14:37 PM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       HR - I agree climate sensitivity is what matters. But that's not the issue here.
91636. KR at 14:31 PM on 23 March 2011
       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.
91637. KR at 14:22 PM on 23 March 2011
       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.
91638. muoncounter at 14:22 PM on 23 March 2011
       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 ...
91639. 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.
91640. Chris Colose at 14:16 PM on 23 March 2011
       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.
91641. L.J. Ryan at 14:14 PM on 23 March 2011
       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.
91642. garythompson at 13:58 PM on 23 March 2011
       Understanding Solar Evolution Pt. 1
       I just read that Sagan paper that was referenced in your first paragraph. There was an interesting portion that I'll quote here: "Major variation in the CO2 abundance will have only minor greenhouse effects because the strongest bands are nearly saturated. A change in the present CO2 abundance by a factor of 2 will produce directly a 2C variation in surface temperature." Granted that Dr. Sagan wrote that in 1972 and there have been many improvements in our understanding of how CO2 affects the Enhanced GHE. In 1972 the CO2 atmospheric concentration as measured by Mauna Loa was 326 ppm and the CRU temp data shows we have gained 0.5C since 1972 while increasing our CO2 concentration by roughly 70ppm or 21% over the 326 ppm level. So we are about 1/5th of our way to doubling CO2 from 1972 levels and we are on track to match the prediction made in this paper that was written almost 40 years ago.
91643. KR at 13:43 PM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       L.J. Ryan - "Earths blackbody temperature is 255K. This represents the theoretical maximum attainable temperature via the suns radiation." To be succinct - Bull - a completely unsupported statement. The surface of the Earth radiates at a temperature of 14C, or 287.15K, with an overall emissivity of 0.98. Upper layers of the troposphere (due to lapse rate) radiate at much higher altitudes, colder temperatures, rendering the planetary emissivity at ~0.612, regulating the amount of energy radiated at any temperature, and driving the surface temperature to the aforementioned 14C. Please - read some physics, get a clue. --- Folks, L.J.Ryan has shown either a complete lack of physics understanding, or a deliberate set of obfuscations. None of his objections has made sense. Damorbel is (in my opinion) a complete troll - he hasn't defended a single assertion, but keeps raising red herrings whenever pinned down, as he has done for over 4 months on this thread. He is now (as others have noted) circling back to previous disproved notions from several months ago, presented as fresh to people who have joined the thread. We are being trolled - do not feed the trolls. Moderators, John Cook - I'll join with previous posters; this cycle of denial and red herrings has gone on long enough. Are there any options in this regard? Perhaps deleting postings repeating junk from months ago? For some reason this particular thread attracts people who think that they either understand thermodynamics better than the previous 150 years of physicists, or perhaps feel that deliberate obfuscation and "common sense" arguments will draw out the discussion. 16 pages, >770 posts, with every skeptic argument repeated multiple times. Gah...
       Moderator Response:

       [DB] "We are being trolled - do not feed the trolls."

       I will join you out on that limb.  Short of a comment directly violating the Comments Policy, what we can do is this: Merely repeating a previously expressed position without adding anything new is indeed grounds for moderation.  So if anyone notices a comment being lifted from a previous one without anything new being added, bring it to the Moderator's attention. 

       700+ posts is a lot; the Mods are human & can't be expected to remember each and every post.  So help each other out:

       1. DNFTT (no matter how much you want to, Do Not Engage)
       2. Be on the watch for recycled comments by those obviously clogging up the threads
       3. Let the Mods know when you see those recycled comments

       Trolls live for attention & generating controversy; deny them the pleasure.  Those that abuse the priviledge of participating in this community may lose that priviledge.

       Thanks for your time.

91644. garythompson at 13:33 PM on 23 March 2011
       Understanding Solar Evolution Pt. 1
       Great post - As an amateur astronomer (and I stress amateur), I really enjoyed this post and look forward to reading the sagan paper referenced in the first paragraph. I've read only the high level articles explaining the HR diagram, main sequence and stellar evolution but I enjoyed a more detail look at the science. For those of you, like myself, who couldn't access that link due to the pay fire wall, here is another location.
91645. scaddenp at 13:31 PM on 23 March 2011
       It's the sun
       John. Nope. Spectral signature in IR range is insignificant. We measure spectra at TOA and earth-bound and what we see is consistent with GHE, not your idea. "Our contribution to CO2 etc is nothing compared to that produced by vulcanism." This is false. See Volcanoes and global warming Global warming occurs for complex reasons ( and not that well understood by the so-called experts)and attributing it to man made pollution (alone) is nonsense. Care to support that assertion with some science? You might also like to look at Climate has changed before
91646. IanC at 13:15 PM on 23 March 2011
       CO2 has been higher in the past
       Jay Cadbury (in response to your comment from Preventing Misinformation thread) Seeing that the current fauna is very different from what you would find all those years ago, I am not sure how comparing the projected temperature and CO2 to their respective values in a such a distant past relevant. What strikes me the most is the fact that even during the wild prolonged swings seen in the Volstok ice-core data, the warming was 10 degrees per 10,000 years, or maybe about 0.05 degrees per century (assuming arctic is warming twice the rate of the global average as it currently is); this pales in comparison to the projected warming (2 degrees per century even on the low end), which is a factor of 40 difference! Whereas in the past longer living mammals have 100s of generation to adapt, now it becomes two generations or so. How can this not be significant to the entire biosphere? While humans as a whole are adaptive, I think there are two caveats 1) Adaptability comes at a price. Most studies on the economic impacts of GW concludes that it is cheaper to cut back on GHG now rather than to adapt. 2) Adaptability depends on the wealth of the country. While people in developed countries are better at adapting (we can buy food from chile if crops from mexico fails), but what will an African family do when crops fail? What will a village in indonesia do when fish stock crashes?
91647. RW1 at 13:13 PM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel (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? "No amount of refocussing etc., etc., of photons from a cold (255K) source, like the upper troposphere, can produce a temperature higher than 255K... anywhere. It's the photons you see, they don't have enough energy. They may have all the power (W/m^2) you can imagine* but no amount of refocussing, adding together, accummulating in reflecting cavities etc., etc. will raise their energy. Or, in other words, increase the temperature of.... anything. That is what the 2nd law is all about." Not really. The second law primarily states that heat can only flow from warm to cold - not the other way around. The atmosphere is largely transparent to the energy coming in from the Sun. The bottom line is the rate the incoming energy can leave the system from the surface is slower than the rate it is coming into the surface. 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. 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.
91648. johng8seq at 13:07 PM on 23 March 2011
       It's the sun
       

       Going back to the original premisen that because solar radiation has reduced since 1960, the sun has nothing to do with global temperature rise - this agument is flawed. The reason being that according to Wein's Distribution Law for black body radiation, if the sun has cooled such that its total radiation has reduced, then the radiation peak will have also shifted towards the infra red. These means that the Earth is likely to receive more insolation because we know the Earth absorbs radiation in the infra red region than at higher frequencies ( shorter wavelengths )due to the greenhouse ( and other effects ). Hence the rise in global temperatures. Global warming occurs for complex reasons ( and not that well understood by the so-called experts)and attributing it to man made pollution (alone) is nonsense. It has occurred in the past and will occur again in the future. Our contribution to CO2 etc is nothing compared to that produced by vulcanism.

       Response:

       [DB] Welcome to Skeptical Science!  There is an immense amount of reference material discussed here and it can be a bit difficult at first to find an answer to your questions. 

       That's why we recommend that Newcomers, Start Here and then learn The Big Picture.

       I also recommend watching this video on why CO₂ is the biggest climate control knob in Earth's history.

       Further general questions can usually be be answered by first using the Search function in the upper left of every Skeptical Science page to see if there is already a post on it (odds are, there is).  If you still have questions, use the Search function located in the upper left of every page here at Skeptical Science and post your question on the most pertinent thread.

       Remember to frame your questions in compliance with the Comments Policy and lastly, to use the Preview function below the comment box to ensure that any html tags you're using work properly.

       With that out of the way, there is much indeed wrong with your comment, more than can be summed up by just one thread post.  Please break up your many objections into their individual parts and post them on the appropriate thread (that's where the Search function will help you).  Thanks!

91649. scaddenp at 13:01 PM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Tedious indeed. If you got past the idea that the atmosphere is warming the planet and bothered to learn how the GHE effects, then you would get some progress. Remember nature is the atmosphere. Your version of physics doesnt account for the observed world. The textbook version does. Is that a hint?
91650. HumanityRules at 12:55 PM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       55 dana1981 OK I was just thinking about what really matters, I guess we have different priorities. 1) Too much wiggle room to for this to be accurate. 2) I agree with you 3) The basic physics only tells us so much and I think is largely uncontested. It's how this is mediated by the the complex, chaotic system that differentiates trivial AGW from catastrophic AGW. The basic physics doesn't give us climate sensitivity and that seems to be what ultimately matters.

Prev  1825  1826  1827  1828  1829  1830  1831  1832  1833  1834  1835  1836  1837  1838  1839  1840  Next