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YouTube video on the empirical evidence for man-made global warming

Posted on 28 February 2010 by John Cook

A common skeptic argument is that there is no empirical evidence for man-made global warming. People who make this claim can't have looked very hard. As most don't have the time to scour through the peer-reviewed scientific literature, the multiple lines of independent evidence for global warming are given here. To make the science even more accessible in this time of multimedia and short attention spans, there is now a YouTube video outlining the empirical evidence for man-made global warming.

The video is by greenman3610, producer of the Climate Crock of the Week series. Also be sure to check out the (more info) link in the right margin where links to all the peer-reviewed papers are provided. This is a powerfully visual way of communicating the science of climate change - I strongly recommend you all view the video, pass it onto your friends (and if you're feeling really energetic, follow the paper links to learn more about the science).

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Comments 101 to 150 out of 156:

  1. By the way, Karl, let me suggest that instead of starting from the bottom with trivialities in attacking anthropogenic climate change, you should instead try a change of tactics and begin at the top. If it's a scientific case you want to make, you really do need to change your approach because eventually folks are going to notice there's little significance in arguments of the sort we're entertaining just now. For instance, if you've got a problem with CRU, instead of looking at their social comportment in writing email, use the ample data available (95% apparently) and do an analysis showing where they've gone off the rails. Dr. Jones himself says there's no rocket science in their work, more drudgery. So if you've going to argue, make a powerful argument if you're able.
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  2. doug_bostrom "So if you've going to argue, make a powerful argument if you're able." The AGW model consists of pitting all known radiative forcings against one another, such that global temperatures will ultimate stabilize around the equilibrium that these vectors produce in their sum. I assume the model also contemplate that this equilibrium point has to do with a rise in ocean temperatures where energy is actually stored. As far as the effects of man-made GHGs, the only significant issue is how the extra energy produced by the presence these GHGs is rising the temperature of the oceans, or their theoretical ability to do so. So it would seem logical, for starters, to only be concerned with this relationship. The problem (or the "power" as you say) with this is approach is that it is too simple, and would very quickly put an end to the discussion.
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  3. thingdonta wrote: "I also dont think that Gary Thompson is 'eyeballing graphs' as claimed in the above article, ....I feel sorry for Gary, ...." I feel sorry for Gary too, but maybe for a different reason. Ignoring graphs which show a statistically signifcant difference where he did not want to see one, is not good science... in fact it is the type of "theory-laden observation" you are talking about. Scientists only "see the models"? Very little of modern science would get done without models. Every climate denier is using a model. How much astrophysics, oceanography, geophysics, materials science, civil engineering (the list goes on...) would get done without modelling? The trope "you're using models, I'm using data" falls apart upon examination. I must concede on the Eugenics, but where there was Julius Rosenberg and Houston Stewart Chamberlain, I see people like Watts and Sarah Palin.
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  4. RSVP at 19:09 PM on 2 March, 2010 I'm sure you meant "retained" where you said "produced". I'm not sure what you mean when you say that focusing attention on the oceans would quickly end discussion. Can you elaborate on that?
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  5. doug_bostrom You are right. I should have said retained. There are different analogs that can be used. An electronic circuit could be used, oceans being a giant capacitor, etc. In some earlier posts, a leaking barrel was used where the water level was the analog for temperature, and inflow was energy in, and outflow was energy out. The comparison was OK, but not correctly proportioned. It would have been better to compare a huge damn (this being the thermal capacity of oceans) and tiny creek at one end, that being the effects of CO2 on the damns water level. My sense is that the amount of IR energy coming from the extra CO2, which in turn is warming the surrounding "passive" gases, which in turn are convectively passing this heat on to the oceans, is miniscule compared to the total thermal capacity of all the water in all the oceans of the Earth. Whereas the AGW model is concerned with comparisons of relative radiative forcings, what matter for the discussion is only the relationship between the additional energy flux due to the effects of man-made GHGs, and what percent of this energy is actually getting stored in the oceans, that is if global warming is understood or defined as "drift" (using a circuit analog).
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  6. RSVP, concentrating ONLY on the oceans simplifies the situation somewhat... they are the MAJOR, but not sole repository for the extra energy accumulating within Earth's climate system as a result of rising GHGs and feedback effects. A graph showing both the ocean and other energy accumulation has been posted here several times before; You seemed to be suggesting that scientists have shied away from examining this as it could definitively prove or disprove AGW. As seen above, nobody has been avoiding it. However, on its own this actually does not prove the SOURCE of the extra energy accumulating in the Earth's climate system. The strongest measured (rather than modeled or theorized) indicator of that is the observed increase at the Earth's surface of wavelengths absorbed and re-emitted by GHGs.
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  7. I should have included a reference to the underlying study, (Murphy 2009), for the graph in the prior message.
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  8. . #100 doug_bostrom Surely you jest. Please do a google search on "IPCC" and "funding", you'll see their efforts to secure "massive amounts" of funding for their cause. With regard to scientific bias, it appears that you are in agreement with my statements that it has and does effect scientific studies. We only disagree as to the level of bias is acceptable when developing analysis used to secure others money.
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  9. @108 Karl_from_Wylie If the IPCC has such large amounts of cash, why is it the bulk of its work undertaken by unpaid volunteers - that is by the thousands of scientists who contribute as authors or reviewers to the IPCC reports at no remuneration and whilst still doing their day jobs? Why does it have just 10 full-time staff in its secretariat at the World Meteorological Organization in Geneva, plus a few more staff in its technical support units?
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  10. . # 109 lord_sidcup IPCC requests that others spend large amounts of money to combat Global Warming. When asking others to spend their money based upon your data and analysis, be prepared to have your proposals reviewed closely and with a critical eye.
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  11. RSVP: "The AGW model consists of pitting all known radiative forcings against one another, such that global temperatures will ultimate stabilize around the equilibrium that these vectors produce in their sum." That's a great example of cargo cult science - it has the appearance, but no substance. You're ignoring all the physics, the chemistry, the biology - that's not science. For example: the interior of the Earth is very warm. Is this a major factor in the surface temperature? No - it's a very minor factor. There's some heat transfer from hot springs and ocean vents, but it's tiny in comparison to the solar inputs. The ground gets cold at night, after all. Here's another: If you increase the percentage of infrared-absorbing gas in the atmosphere, does that result in a warmer atmosphere and surface? Yes! Clear nights are colder than overcast nights, everyone knows that. It's because the Earth's heat is lost more rapidly to space when there are fewer greenhouse gases in the air. To get estimates, you need models with complicated mathematical structures - and yes, vectors come into play. But what you are doing, RSVP, is just the cargo cult version.
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  12. P.S. on this comment: As for dead canaries in coal mines, the statament itself carries all one needs to know-canaries dont usually live in coal mines, they arent adapted to them, they have no biological exposure or history to them(unlike eg natural warmings) so how can one use this cruel analogy with anything to do with climate change? Well, we are taking what's down in the coal mine and exporting it all into the atmosphere, the rivers and streams, and the soil. Coal combustion releases tonnage quantities of mercury and arsenic and other potent toxins into the air and water - which makes sense, since coal plants burn as much as 10 million tons of coal a year, and resulting in a few tons of mercury and arsenic and several thousand tons of sulfur and nitrogen oxides being pumped into the atmosphere - plus your 27 million tons of CO2 (10 million tons of coal = 27 million tons of CO2 on combustion) From there, the mercury and arsenic rains out into rivers and streams, accumulates in insects and fish, and so enters the food web - everything from eagles to humans gets loaded up with mercury, leading to various levels of neurological damage, etc. A few people doing burning coal won't affect the climate, even if they poison their local surroundings - but what about 7 billion people burning coal? The canary in the coal mine analogy seems perfectly appropriate - since the idea, cruel as it may seem, was that by watching the canary, human lives could be saved (now, they have sophisticated gas monitors - no animals need be sacrificed). Of course, if you knew the mine was full of gas, you probably wouldn't send the canary down into it, would you? So, if we see a whole host of wild species uprooting themselves and changing their behavior, and it seems to correlate with the changing climate - well, maybe we should pay attention, huh? Maybe we shouldn't send hundreds of species down into the coal mine after the canary, just maybe?
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  13. Karl_from_Wylie at 01:19 AM on 3 March, 2010 Karl, I need to tell you that I cannot sympathize with your worries about money as they relate to science. The vector of cash flow is dependent on physics and the outcome of physical processes but money cannot be used to describe physics. You're wrong; IPCC is not seeking massive amounts of funding. You need to refine your argument. I do not agree with you that bias significantly affects validated results of scientific inquiry, though I do believe personal predilections will help to steer any individual scientist's preferred course of inquiry.
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  14. CBDunkerson The area under the curve (Calculus 101) represents the total energy accumulated over all these years. I guess I would ask just one question. Could GHG have trapped all this AND at the same time leave Earth´s temperatures more or less the same? Sort of like a household budget where for years every month you basically spent every penny with zero saving, and then find out you have million dollars in the bank. Unless you have a rich uncle (under sea volcanic action, etc.) this is quite impossible.
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  15. . 113 doug_bostrom Please be more careful in reading what I've acturally written rather than how it can be interpreted. "massive amounts" of funding for THEIR CAUSE." IPCC seeks funding of the cause of Global Warming. See link below for list of edicts they have made sorted by industy. http://www.ipcc.ch/...mitigation_of_climate_change.htm
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  16. Karl_from_Wylie at 07:24 AM on 3 March 2010 Karl, how I interpret what you write depends on the ambiguity your writing leaves unresolved. To what "cause" are you referring? Is there a manifesto, and if so where can I read it? And who are "they?"
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  17. . #117 doug_bostrom It does no good writing if you will not read. I clearly answer your question, "To what "cause" are you referring?" in the previous post.
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  18. Karl_from_Wylie at 07:46 AM on 3 March 2010 Well, if you must leave it at that what I interpret from your writing is that you believe scientists have formed a political unit espousing an unstated cause. I don't see evidence for that in the IPCC reports.
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  19. . #118 doug_bostrom You are once again reading into my posts what is not written. Read only what is written. You're a smart man, it is not hard to understand.
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  20. Karl_from_Wylie at 08:06 AM on 3 March, 2010 I am indeed forced to read from your posts what you have not written. Your descriptions are incomplete and you leave me the reader to fill in the gaps you have left. What is it you would like me to understand about the IPCC "cause?" Who are the proponents of that cause? What is their ambition?
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  21. doug_bostrom The cause to which I referred above is actions (read money) that they prescribe others must take(read money) to reduce Global Warming. Link provided above. With regard their "ambition", I would not know.
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  22. Karl_from_Wylie at 08:22 AM on 3 March, 2010 Karl, that does not sound like a very robust argument against what we seem to know of physics-- principles that work in many areas other than climate research-- but let's pursue the idea for just a moment. At what point in time and concepts did real science stop and fake science begin? More specifically, when and how did the conspirators you propose are promoting a hidden agenda bridge the gap between accepted scientific principles and fiction? It seems to me that's the tricky part of conducting such a campaign. So, if you can pin down the transition from science that works everywhere else to how the same principles are made to appear to work for climate research without actually doing so you'll have the beginnings of a case.
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  23. RSVP, no the top line of the curve represents the total accumulated anomaly from the 1950 value. Also no, energy could not accumulate in the Earth's climate system as shown without the planet warming... as it has. Your analogy makes no sense to me (how is 'more energy being retained' equivalent to 'NO money being retained'?), but I gather that you are trying to claim that fluctuations in the ~0.1 watts/m^2 average energy emitted from within the Earth to the surface is a more likely candidate for ocean heat accumulations than better retention of the ~1370 watts/m^2 coming in from the Sun. Sorry, but its like claiming that you can boil a lake with a Bic lighter. On a global scale volcanoes are TINY.
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  24. # 122 doug_bostrom My argument is very strong. You've already agreed with me. GOAL - Climate Scientists have biases just like others. My goal is neither prove or disprove Climate Change. Your assumption that it is my purpose, reveals a stereotyping of folks with differing views. When you make statement such as.... "...how did the conspirators you propose" "...fake science" You show you've not read any of my postings. No conspirators or alternate science has been discussed. Perhaps all skeptics look the same to you.
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  25. At 8:45 of the video one can hear the following: "with more moisture in the atmosphere due to warming, precipitation events are getting more extreme" ("both in Northern and Tropical areas") Could anybody please provide references for "more moisture in the atmosphere" and "precipitation events are getting more extreme"? I have asked at Romm's but only received references for the USA.
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  26. Karl_from_Wylie at 10:40 AM on 3 March, 2010 Would you remind me of exactly what you're arguing? You seem to be hypothesizing that a group of hazy identification is seeking to shift money from one place to another: "Please do a google search on "IPCC" and "funding", you'll see their efforts to secure "massive amounts" of funding for their cause." See, what I'm not clear on is who "they" are, and what is their "cause." If I misread what you posted and you're making a different argument, my apologies. I also apologize for assuming that by appearing on a site dedicated to debunking "skeptic" arguments regarding climate science and proceeding to describe a shadowy group seeking to use climate science to obtain funds for a "cause" you cannot identify, you might be a self-described "skeptic" regarding climate science. Perhaps it would be helpful if you restated your position?
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  27. Getting back to the video at the head of this thread. I am still asking myself whether there is a single respected scientist who could keep a straight face while publicly declaring: "Atmospheric carbon dioxide is a pollutant"
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  28. . #126 doug_bostrom Please define your "shadowy group" for which you have enmity. Please defend the words you use and don't attribute them to any one else.
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  29. Karl_from_Wylie at 15:15 PM on 3 March 2010 I guess I confused you, sorry. It's -your- argument. You have to support it, I don't.
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  30. gallopingcamel at 14:48 PM on 3 March, 2010 CO is a naturally occurring constituent of the atmosphere. Can it be labeled a pollutant?
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  31. #129 doug_bostrom Please do a word search and you'll see that "shadowy group" is your choice of words not mine. Either defend your words or choose them better.
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  32. The term "pollutant" refers to toxicology, and the first thing you learn in toxicology is that effects are dose-dependent, or concentration-dependent. Paracelsus: "The only difference between poison and medicine is the dose." Fertilizer is a key ingredient for plant growth - but we don't call it a pollutant unless it is dumped into our fresh water supplies - and yes, ingesting ammonium nitrate is unhealthy. The herbicides and pesticides are of course far more toxic than fertilizer. So, this word, "pollutant" isn't really well-defined. Another example is ozone - in the stratosphere, it is a vital shield against ultraviolet radiation, but in cities, it is a dangerous component of automobile smog. So, the classic skeptic argument here is that CO2 is a life-giving fertilizer, a key raw material for plant growth - and that is true, if incomplete. Why? Plants take up atmospheric CO2, and use sunlight to split water into O2 and hydrogen atoms. Those atoms are then essentially attached to the CO2 atoms, while the oxygen atoms are sequentially removed, leaving the energy of sunlight stored in the chemical bonds inside sugar molecules. Refined sugar? Think of it as sunlight trapped within the molecular structure of the sugar molecule in the form of energetic electronic bonds... kind of like stretched rubber bands. Cut them, you release that stored sunlight as heat, light, pressure, muscular contractions, etc. No atmospheric CO2, no plant growth. Doubling CO2 across the planet could make photosynthesis easier, the argument goes - but in the real world, usually it's not the CO2 that is lacking - it's the nitrogen, the phosphate, the trace minerals that get depleted from the farmer's fields, and have to be replaced. You can now see why you can grow crops year after year - for millenia - with no effect on atmospheric CO2 - every year, the plants take the CO2 out of the air, and (with the assistance of animals, fungi & bacteria) it ends up being recycled back into the atmosphere. Hence, biofuels are sustainable at some scale. However, if you're dumping fossil carbon into the atmosphere, then you are adding to the pool (you can measure this in the radiocarbon signature of old fossil fuel carbon). CO2 (at these low levels) has no direct toxic effect (unlike on Pandora, where CO2 must be a few % - not bad on the science, there) - it is an indirect effect of slowing warming & destabilizing the climate. Now, the effects of acid rain are largely secondary as well - it strips nutrients out of the soil and that kills trees - and we call acid rain precursors (high-sulfur coal and diesel fuel) pollutants, don't we? If you can regulate secondary acid rain effects due to their impacts on people, pets, livestock, wildlife, and plants - well, yes, you should also be able to do the same with fossil fuel-sourced CO2.
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  33. CBDunkerson at 09:09 AM on 3 March, 2010 Thanks for answering, and I did like your Bic lighter analogy at least in terms of the humor. What I was saying is that the extra heat from CO2 shows up as a warmer atmosphere. Some part of that extra heat (I assume AGW theorists acknowledge this) IS escaping to infinity and some part could be going in "savings" (i.e., the ocean). My question is whether it is possible for that "small portion" of that "difference" could be sufficient to account for all that anomalous energy in your curve?
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  34. skepticalscience.com is one of the few blogs out there that's doing it right when it comes to the global warming "debate," i.e., going to the actual research papers. However, while this video is excellent, as well as the other posts knocking the legs out from under people who deny that the climate is getting warmer, I'm wondering -- who, really, are these deniers? Billy Bob living in a trailer park eating mayonnaise sandwiches? There are people who don't believe human ever went to the moon, but nobody really pays that much attention to them let alone puts in a lot of time and effort trying to debunk their arguments (which will never convince the Billy Bob's of the world anyway). So what's the point here -- or rather, what's the big news? The climate is warming? "Everybody" knows that. True, there are influential senators (Inhofe) and media personalities (Glen Beck) who are highly visible deniers, but -- again, really -- how much of a influence are they? Hard to believe that their uninformed opinions are somehow going to turn the tide of thinking on this issue. So, why is skepticalscience.com spending so much time on this? It's not where the real debate is. Recently, Fermilab invited MIT's Richard Lindzen to give a talk at one of their Colloquiums: http://vmsstreamer1.fnal.gov/VMS_Site_03/Lectures/Colloquium/100210Lindzen/f.htm Fermilab is interested because climate change is definitely topical but perhaps more importantly they're interested because almost all the research is based on computational-statistical models, and Fermilab has some of the world best experts in computational and statistical modeling in the world. They're clearly in a position to both understand and critique the computational and statistical methodology that lies at the heart of predictive-based climate research. The Colloquium is long -- it clocks in over an hour, which is a long time for an afternoon colloquium, and then there was a 30 Q&A. What might surprise readers of this blog is that Dr. Lindzen agrees with 98% of this video. I'm not an expert, but listening to his talk, he would disagree with almost nothing here: the climate is warming and C02 plays a role. You'd be hard pressed to find a climate scientist or a physicist that would disagree with that. Where might Dr. Lindzen part company with some readers of this blog? Dr. Lindzen is convinced that climate change global alarm is dead wrong because of the lack of evidence for positive feedback in the climate. Anyway, this was an influential talk and it's making it's way around the net and in professional academic circles. I'd like to see skepticalscience.com review this talk. - Cheers, libertarianromanticideal.com
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  35. Karl_from_Wylie at 15:28 PM on 3 March 2010 Karl, I'm afraid I've lost your plot. I gather you've some issue with IPCC being involved in pushing some sort of cause, but you're not able to supply any details so I've had to tease some meaning out of your words. "Conspiracy" was too strong, so I tried "shadowy" and apparently that won't do either. Perhaps "mysterious" or "unidentified" (come to think of it, I believe I tried that one) will do. You have the last word on this, be my guest. I don't see the relationship of your hypothesis to science but if reading tea leaves is your bag I'm not going to stand in your way.
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  36. ike solem at 15:57 PM on 3 March, 2010 This business of whether C02 is or is not a pollutant is a big deal in some quarters. Tagging C02 with a "pollutant" label is going to cause a shift in public perceptions and that's an unaffordable loss for fossil fuel interests. Hence the sudden emergence of "grass roots" web sites and the like, extolling the virtues of gusting in great lungfuls of clean, healthy, natural and purely harmless C02. The proper quantity of fish oil in a fish is naturally occurring and undoubtedly absolutely necessary to the proper functioning of a fish. One thousand gallons of fish oil dumped in a river will impair the function of that river, is thus a pollutant and comes under the purview of the EPA. That's not complicated, and neither is the notion of C02 being a pollutant if its concentration is raised by humans to levels determined to interfere with the proper functioning of the planet. Expect your immediate future to include repeating variations of this argument an astronomical number of times using a multitude of analogies as a man made fog of obfuscation enshrouds this very simple concept.
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  37. RSVP at 16:12 PM on 3 March, 2010 The heat content energy in inferred from increasing temperature of the oceans and the troposphere (plus heat capacity of air and water and fusion heat of ice). So, escaping radiations aren't part of it. Neither are escaping radiations part of CO2 forcing. Increase in any GHG forcing results from summing the instantaneous (not accounting for feedbacks) decrease in outgoing radiation from the tropopause with the increase in surface irradiation from the atmosphere. This causes the transient energy imbalance of the Earth+troposphere system while GHG concentrations are increasing and before a new radiative equilibrium can be attained.
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  38. libertarianromanticideal, maybe one 'skeptic' in a hundred will cite Lindzen's views... and most of those will have the details wrong or out of date. Polls show that 'GW skepticism' is growing... but discussion shows that this growth is fueled primarily by the arguments which are provably false. Thus, the focus of this site on identifying those arguments and linking to the contradictory facts. As to Lindzen... he has been fighting a rear guard action on global warming denial for more than twenty years and is now reaching his last stand. The one claim he can still make with some small degree of veracity is that we don't know all the details of all possible feedbacks and thus the models could be wrong. This is close enough to 'true' to keep him within the fold of scientific endeavor... but just barely. Extensive data from AIRS and other readings have established the extent of water vapor feedback to a high degree of certainty... and found it to be consistent with what the models have been using for decades. Readings from IceSat, GRACE, and other sources have shown conclusively that the ice albedo feedback effect is progressing more rapidly than all but the most pessimistic models projected. Between them, those two factors constitute most of the positive feedback used in the models. Thus, we have reached the point that strong positive feedbacks are a demonstrated result... Lindzen has maybe a few more years of claiming that there could be errors in the data before the growing list of confirmations push that completely out of the realm of reasonable objection. He has thrown out several hypotheses of implausible counter feedbacks to blunt the warming, but each has been examined, shown to be faulty, and eventually withdrawn. So yes, from a true scientific standpoint Lindzen is the skeptic to consider... but every argument he has made has been strongly refuted (most of them on this site amongst other places) and is just waiting for the evidence against it to become overwhelming.
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  39. #80 Riccardo at 09:00 AM on 2 March, 2010 "i can only suggest to read" OK, I have read the paper + supplement. It does not elaborate on observations inconsistent with warming at all. It just mentions some out of those three thousand with no further comment. However, here is a huge one. Data from Rutgers snow site I have just considered Norhern Hemisphere average snow cover for winter months (December-February) and assigned value to year containing mid month (January). There are data for 44 consecutive years from 1967 to 2010. Long enough to contain some climate signal, right? Well, no linear trend at all. Nope. Flat like truth itself. However, I could make it scary if I wanted to. Just have to use quadratic fit instead of linear. Projected NH snow cover for year 2100 is 76,440,839 square kilometer, an incredible 70% increase relative to 1967-2010 average. Mexico, Northern Africa and parts of India to be frozen. It is a joke, of course. Shows how shaky extrapolation can get. Null measurements are the most reliable ones in physics. Electric field in a conductive envelope is measured to be zero. With some math it is a hard proof of inverese square law for Coulomb force. The NH winter snow cover trend is a null measurement. It does contradict to mainstream climate theory. From IPCC AR4: 1. WG1 4.2.2.2 Variability and Trends in Northern Hemisphere Snow Cover "Temperature variations and trends play a significant role in variability and trends of NH SCA, by determining whether precipitation falls as rain or snow" 2. WG1 8.6.3.3 Cryosphere Feedbacks "A robust feature of the response of climate models to increases in atmospheric concentrations of greenhouse gases is the poleward retreat of terrestrial snow [...]" 3. WG1 10.3.3.2 Changes in Snow Cover and Frozen Ground "Snow cover [...] exhibits strong negative correlation with air temperature" etc.
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  40. libertarianromanticideal (@134), IMHO this is way the best blog of its type. A class act like this one attracts some very thoughtful people. Even though I disagree with most of the comments I still get the feeling that it would be fun to meet the debaters over a glass of beer. There is no real debate at "Climate Progress" because Joe Romm blocks posts he does not like. Tim Lambert's "Deltoid" is much better but it seems to appeal to the loony fringe who descend into name calling when challenged. Thank you John Cook!
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  41. First, go watch the video again. All of those claims are based on decades of research and thousands of published papers. Most of that effort went into understanding the steady-state system of the atmosphere, oceans, ice bodies, biosphere and land surfaces - and this basic science work was critical. None of it ever mentioned global warming, but it allowed people to understand the global circulation of water and energy in response to solar inputs. Now, we understand this well enough that we could do a decent job of predicting the climate on any Earth-like planet, as long as we knew the atmospheric gas composition, and some other factors (ocean volumes, land mass distributions, biomass, ice sheet volume, etc.). The core disciplines involved were physics, biology and chemistry - which is science. This quote, on the other hand, by "libertarian romantic", is cargo cult science: They're clearly in a position to both understand and critique the computational and statistical methodology that lies at the heart of predictive-based climate research. Actually, you have physics, chemistry and biology at the heart of climate research. Each "Earth Science" discipline involves some mix of the above three, cobbled together mathematically. The lines of evidence for global warming are all based on methods originally developed in those three disciplines, and then applied to data collection, computer modeling, "canary in a coal mine" studies, and paleoclimate studies. Now, as far as getting Fermilab to "doublecheck everything" - would you hire the world's best dentist to do heart surgery? You might ask the dentist to point out any issues with your heart surgeon, but why not ask other heart surgeons? Climate models are radiative transfer & fluid dynamics models at heart. It's the coupling of those two main physical areas that allows one to create a radiative-convective model. This is how you make a weather model, which, if initialized with real-world data, can produce fairly accurate weather forecasts up to about a week or so. However, if you run the model for a very long time, it still produces weather patterns and seasons, but they don't match up, time-wise, with reality. Climate, however, is the average of weather over time - and if you average the model, you get a good fit with climate. However, over long periods of time the ocean and ice sheets and biosphere start playing major roles. Hence, you now need ocean models coupled to biomass models coupled to ice sheet models and so on. Obviously, there are thousands of papers on the development of all these model components - go and look. So, why do you want FermiLab - which works with high-energy particle physics models - to look at climate models? Why not have people who specialize in galactic cosmology modeling go and double-check the FermiLab people, while you're at it? And then climate modelers could go and make sure that aircraft designers aren't messing up their fluid dynamic equations... Or, you could just go read the methods sections in the published literature, where all that has been done, over and over again.
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  42. BerenyiPeter, how is the snow cover over the entire year? Your trick is interesting, how does it play out with other months? I look at your first link and I found this: "Interannual variability of SCA is largest not in winter, when mean SCA is greatest, but in autumn (in absolute terms) or summer (in relative terms)." A little farther down there is this: " Since the early 1920s, and especially since the late 1970s, SCA has declined in spring (Figure 4.2) and summer, but not substantially in winter (Table 4.2) despite winter warming (see Section 3.2.2)." And this: "From 1915 to 2004, North American SCA increased in November, December and January owing to increases in precipitation (Section 3.3.2; Groisman et al., 2004). Decreases in snow cover are mainly confined to the latter half of the 20th century, and are most apparent in the spring period over western North America (Groisman et al., 2004). Shifts towards earlier melt by about eight days since the mid-1960s were also observed in northern Alaska (Stone et al., 2002)." You selectively quote WGI about models. All readers can see your quote above, it is important to note that it is followed immediately by this: "At the same time, the high-latitude response to increased greenhouse gas concentrations is highly variable among climate models (e.g., Holland and Bitz, 2003) and does not show substantial convergence in the latest generation of AOGCMs (Chapman and Walsh, 2007; see also Section 11.8). The possibility of threshold behaviour also contributes to the uncertainty of how the cryosphere may evolve in future climate scenarios." Your 3rd quote is also selective and thus misleading. As for the other 2 links, I recommend to read the full text, where this can be found: "The individual model projections range from reductions of 9 to 17%. The actual reductions are greatest in spring and late autumn/early winter, indicating a shortened snow cover season (ACIA, 2004). The beginning of the snow accumulation season (the end of the snowmelt season) is projected to be later (earlier), and the fractional snow coverage is projected to decrease during the snow season (Hosaka et al., 2005)." Your argument is very reminiscent of a recent WUWT post by the same guy who once defended the possibility of carbonic snow in Antarctica. Tamino took a look at the whole picture: http://tamino.wordpress.com/2010/02/18/cherry-snow/ The same Rutgers data you use shows a yearly decline of 37000sq.km/yr between the late 60s and present time. The decline is strongest in the summer months, which is exactly what the models suggest should happen. Your characterizations of the state of snow cover and model projections were both in error. Models suggest that winter snow cover will not change significantly at first with sme regions experiencing more snow due to more humidity, rendered possible by higher temps. Other seasons, however, will experience decreased cover. That happens to be what the Rutgers data show. Models also suggest a later start of the snow season and earlier melt, with poleward movement of the permafrost. That has also been observed already, and the very links you provided contain the references. You say: "The NH winter snow cover trend is a null measurement. It does contradict to mainstream climate theory." That is false, and the links you gave indicate as much.
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  43. #142 Philippe Chantreau at 04:29 AM on 4 March, 2010 Philippe, area of snow cover can only increase along the edges, not in the middle of already snow covered regions. At edge of snow temperature should be somewhere around freezing point. If winter snow coverage does not decrease, the line separating regions above and below freezing point can not move North. So NH winter snow coverage is a good (semi)global thermometer. Increased precipitation can not account for stability of winter snow cover, because if temperature is too high, one gets rain, not snow. Spring snow cover is not a very good indicator. In Northern Hemisphere insolation in spring is increasing rapidly, temperature goes up, snow melts. Spring weather is solar driven. One does not have to be an expert to know that much. In winter solar forcing is at its minimum, relative to it CO2 forcing should be more prominent. It is not. For an already cold snow covered landmass there is no other way to get even colder than either by pushing heat poleward or radiating some heat out to space for it is the coldest heat reservoir around (2.7 K). From polar regions, heat can only get out of the system, it has nowhere else to go. CO2 somehow can not trap it.
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  44. In regions where the temperature is already low in the winter, higher temps will bring more precipitation, which will still be in the form of snow as long as the temp is below freezing. Having the average winter temps go from -6C in any location to -2C would constitue a huge increase in temp but would not yield any less snow. In fact there would likely more of it. Spring insolation has not changed with time, it certainly does not explain a trend of higher spring temperatures. The same applies to summer and autumn. In any case, your rendition of model projections and of what is said in the IPCC links you provided is not faithful to the reality of either. The model projections, once again, are in agreement with the data. As for you forcing reflexion, CO2 forcing depends on IR radiation coming from the surface, heated by solar irradiance. I would expect high albedo surfaces to convert much less solar irradiance into IR. I would also expect a surface in darkness most of the day to act somewhat the same, to a lesser extent.
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  45. Re: #144 OK. Do you have data on history of regional distribution of NH winter snow? Lack of snow cover can be due to either low moisture or high temperature. If you are right, NH winter snow cover during the last four decades increased in dry areas while decreased elsewhere by roughly the same amount. This hypothesis can be tested, it is falsifiable in principle. However, this winter has not shown this pattern. There was heavy snow in Western Europe, US, Korea & China. None of them is a desert, get plenty of rain during winter if not snow.
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  46. Departure from Normal 2009 December 2010 January 2010 February
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  47. Berényi Péter at 10:26 AM on 4 March, 2010 You'll probably be interested in looking at Tamino's take on this: Cherry Snow He concludes there's no statistical power to conclude models have been upended by aberrant snow cover.
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    Response: You know, what would be great here is if one of you added the argument about snow cover to the list of skeptic arguments. Then as you argue back and forth with URLs, you also add the links to the directory.

    Hmm, maybe I should write some code where if someone posts a URL in a comment, it follows up with a reminder: "hey, don't forget to add this to the directory" with a link to the Add Link Form. :-)
  48. Berényi Péter, the linear fit is meaningless, look at the residuals (yearly averages, i'd suggest). I would not trust a second order polynomial extrapolation either unless you have good reasons to believe it will follow this law. In other words, your analysis says nothing valuable on what will happen in 2100, let alone "a huge one" or "contradict to mainstream climate theory". It's could be just a statistical trick to make things look "scientific" and i'm sure it could also work in some quarters. But you know, people here tend to believe that real science is much more serious than just this.
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  49. Hi CBDunkerson, I think you've probably characterized Dr. Lindzen here. He's certainly fodder for the global alarm contingent, but w/in the academic sphere, the man is highly respected and regarded, as much as any scientist can be w/in his field. There's simply no question about that. Fermilab is not only the institution that's invited him to give talks. These institutions do so because he's an acknowledged expert in the field, and he has something to offer. They wouldn't invite him if they didn't think that. Within the field, his hypotheses and work are not regarded as "reaching [their] last stand." He publishes, he has research grants (try to get one of those!), he trains post-docs, who need 1) an adviser who publishes at a regular rate, with their names on the paper, and who 2) gives them an opportunity to extend the work done in his lab, to present that work at conferences, and -- hopefully -- to publish. The competition for beginning (i.e., associate professor) tenure track academic positions is fierce. If the guy was on some sort of "last stand," post-docs simply would go elsewhere. That's not the case (see: http://www-eaps.mit.edu/faculty/lindzen/students.html, and http://www-eaps.mit.edu/faculty/lindzen/students2.pdf). The man is working scientist, he has a working lab which is a publishing factory -- he's doing his job and he's good at it. Period. Additionally, other experts in the field put his ideas to the test. And other researchers put their ideas, theories and hypotheses to the test, and so on. While no one completely agrees with anyone else (they may not even like them), everyone takes everyone's else work and ideas very Very VERY seriously, even if they disagree. They're paid thinkers, all of them. That's their job. If somebody stops "thinking," or they start beating a head horse, their academic research career is over, nobody invites them to talks (because they have nothing new to offer, which is the point of these professional talks), potential post-docs go elsewhere, research grant money dries up, and they stop publishing. This is definitely not Lindzen's situation. In fact, he's done something quite unusual, extremely difficult, and highly valuable. He's one of those rare researchers that is thriving in a minority camp. That's rare and it takes talent. Everyone in his field respects that. You can take that to the bank. Finally, what's the field's current stance on the issue of positive feedback mechanisms in the climate? It's not a closed issue. Copy and paste this in your browser's URL window: "forcing feedback" site:.edu This tells google to search for this keyword phase across all academic domains. You can also do a search across all government domains, e.g., "forcing feedback" site:.gov There's 100's of papers, talks, discussions. And these google searches almost certainty under-estimate the interest in the topic. If it was close to being a closed and decided issue, you would see a very different set of hits. For example, if you instead google this: either "speed of light" site:.edu you'll get 10's of thousands of hits, but ZERO are about anything seriously asking the question, "hummm . ... what effect does the 'either' have on the velocity of light?" The either theory was dis-credited by the the theory of relatively over 100 years ago. All these hits are about how the theory was dis-credited. None of this means Lindzen is "right." It does mean he's highly relevant to the discussions currently ongoing w/in the climate research community. - Cheers, Christopher Skyi, http://libertarianromanticideal.com/
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  50. libertarianromanticideal, I never thought of myself as a sycophant but I find myself in awe of your analysis (#143). Richard Lindzen commands respect that most scientists can only dream of. Lindzen lacks the hubris and over-reaching that characterises the IPCC and its acolytes. He admits that he cannot predict whether the global temperatures will rise or fall by 2100. The IPCC on the other hand predicts with 95% confidence that global temperatures will rise by 2 degrees Celsius by 2100 and possibly as much as 7 degrees Celsius. Given that global temperatures have risen by only 0.7 degrees since 1860, the huge temperature rises predicted by the IPCC should have become noticeable by now. BTW, the Fermilab folks are a blast. I got five 500 kW precision power supplies from them as a gift! Spares too!
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