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Comments 71051 to 71100:

  1. Watts, Surface Stations and BEST
    Much as I think Watts and co have always been clutching at straws in their attempts to discredit temperature recordings, I do worry about this argument offered in rebuttal:
    "Rather than draw readers' attention to the hot spots, I would invite readers to compare the color (temperature) of the instrument housing with the color (temperature) of the general surroundings. In each case, the temperature station casing is - despite being near a source of heat - at the same temperature as the nearby land."
    My gut reaction to that statement is; well, that's what one would expect, wouldn't one -- given that the weather station and its general surroundings are arguably both equally influenced by the nearby heat source in question? I'm not sure this is such a good argument and in the absence of any scientific study in support of its validity, I would suggest it's removed. As far as I'm concerned the 'BEST' and 'Fall et al' studies have demolished the 'station siting' myth and we should move on.
  2. Watts, Surface Stations and BEST
    Stevo @9: If you changed the coating, then you would expect a 'jump' in temperatures. If all stations were coated at exactly the same time, then you might not pick it up. If one were coated and the nearby ones weren't, then the homogenisation procedure would work it out: 'what's this big jump? No-one near it has it, must be something else, let's go check and account for it'.
  3. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    I did something similar using Congressman Rohrabacher's 100 List of scientists: http://profmandia.wordpress.com/2011/04/12/congressman-rohrbachers-paper-tiger/ On three occasions (Feb 4, 2010, March 10, 2010, and Feb 17, 2011), Rep. Rohrabacher has entered into the Congressional record an open letter signed by over 100 scientists and published as a full page ad in the New York Times, Washington Post, Chicago Tribune, Washington Times, and Los Angeles Times. The letter was addressed to the President of the United States and flies in the face of the scientific understanding of climate change. The letter can be viewed here. The letter contained 115 signatures and made the following assertions: 1.The case for alarm regarding climate change is grossly overstated 2.Characterization of the scientific facts regarding climate change and the degree of certainty informing the scientific debate is simply incorrect 3.Surface temperature changes over the past century have been episodic and modest 4.There has been no net global warming for over a decade 5.The computer models forecasting rapid temperature change abjectly fail to explain recent climate behavior The result: Only nine of these 115 (8%) have published recent research which give evidence that they have some expertise in at least one of areas 3, 4, or 5. NONE have expertise in all three of these areas. Worse, more than 2/3 of the signers have NO RECENT PAPERS related to climate yet they felt qualified to sign a letter addressed to the President of the United States to tell him he is wrong and the science is wrong - the arrogance!
  4. CO2 measurements are suspect
    Hi Philippe, thanks for those articles! I was interested to read that the air bubbles trapped in the ice represent the composition at the time of snow deposition. I would have thought there would be some movement of air upwards as the snow was compacting. Do you know of any articles that show the comparison of these readings of direct free air and shallow ice core?
  5. Watts, Surface Stations and BEST
    The bottom photo, that paving ought to be much cooler than the grass surounding it at night. Its only really about human sources of heat like heating or air conditioning that will change the local temperature over 24 hours.
  6. Berkeley Earth Surface Temperature Study: “The effect of urban heating on the global trends is nearly negligible”
    Tom Curtis 36. I have checked the solar irradiance trace from the IPCC graph. it looks correct. There are two green lines, one solid, one dashed. I have used the solid line. It has an upturn to 2000 which is much higher than the 1300 level. I am not sure what the dashed line means. The only inaccuracy I can see is the placing of the end of the line, 1950 on the IPCC graph, which could be squeezed in a fraction on my chart. PowerPoint is not the best tool to use for all this. In due course I plan to redraw it using a proper CAD programme. Meanwhile, if you can point me to any better solar irradiance records than the IPCC chart, I would be grateful. I will also use the Solanki data for solar activity. No agenda here, just would be good to correct any misleading graphics.
    Response:

    [DB] "No agenda here, just would be good to correct any misleading graphics."

    When you say "misleading graphics" do you refer to that of the IPCC...or yours?  FYI, "misleading" is a favorite toy of the fake-skeptic contingent, being used liberally like milk with cereal.  As such, it is a term that can contravene the Comments Policy here, depending upon the context used.

  7. Climate's changed before
    Sphaericq, thanks for the gentle advice. I note that KR told me I was raising a Skeptical Argument , my caps. I suspect that is the touchy point. I have read nothing up on the PETM except Brian Lovells book. My question honestly came out of my own head, as an immediate reaction to the events as described, not off some website. But if the question, as I now suspect from KR's phrase, is a regularly used SA, I can see how KR would react to someone apparently churning out an old mantra. I do appreciate being given the benefit of the doubt. My purpose in using this forum (for which many thanks for allowing me) is to clarify my personal understanding. I entered here rating significant AGW as around 50% certain, now I would rate it as 80 to 95% certain. Lastly, I have seen criticism of some of my posts on the lines of , why dont you read up in depth on the subject before coming here with questions. Simple answer, I would love to, but life isn't long enough. That is why one asks the experts.
  8. Watts, Surface Stations and BEST
    Regarding figure 4. It deserves a quote from the TV series Father Ted. "Now concentrate this time, Dougal. These are very small; those are far away..." Not quite the same context but the image is used to create a notion of conspiracy by using the lack of depth information to suggest the sensor appears to be closer to the electronics.
  9. Watts, Surface Stations and BEST
    chriskoz @12 Thanks for that. You pretty much summed up my thoughts on that one.
  10. Watts, Surface Stations and BEST
    ptbrown31 @6 "We are the 97%" [...] Put that on a mug. What do you mean by this remark? And also can you please explain how it relates to the topic we are discussing here? Stevo @9 I'm in another filed just like you but I guess the average temp anomaly is not biased if the conditions and coatings of given stations stay the same: i.e. if the stations are "re-coated" at some point, then the same coat is used. Still, if they are re-coated randomly according to the taste of the owner. However if they were all gradually re-coated according to the "national fashion trend" or other universal criteria (say from bare wood through latex to whitewash), then those changes could introduce some bias. If I was Watts & trying to disprove the data I would look at this possibility. I wander if Watts (or any other 'sceptic') considered it he is content with just weak allegations...
  11. Watts, Surface Stations and BEST
    "A study using Watts' own data - Menne 2010 - found that station exposure does not play an obvious role in temperature trends, the same conclusion reached by a team including Watts in a later paper, Fall et al 2011."
    I don't think that accurately characterizes Fall et al, which does find bias in min/max temperatures but not average temperatures. IIRC, the authors state that while average temps appear to be robust, this may be a chance circumstance of min/max biases cancelling each other out. I'd quote chapter and verse, but the link to the pdf is broken for me - you should check it. And I'd like to re-read.
  12. Watts, Surface Stations and BEST
    Before mention of Watts' qualifications descend into ad-hom, I would add that the best Watts can be described as is an amateur meteorologist. An amateur has the potential to make significant contributions to a field - in astronomy this happens all the time, but it requires exquisite care and dedication to fully understand the field you are dabbling in, and to understand where and how you can make a contribution. Some easy examples: Faint fuzzy not on the sky chart? Comet! But is it moving, and has it already been recorded? Variable star! What observations exist, and what are the existing explanations for its behaviour? Can you and your equipment accurately record the variations? Supernova! Or is it an asteroid or existing star in front of that galaxy? Those with no astronomical/astrophysical qualifications can make valuable discoveries and observations, but they will not make those discoveries by casually looking through their telescope while ignoring the literature and existing understanding on what it is you are observing. Many UFO sightings stand testament to people making a fuss about something in the sky before they understand all the processes/events that may provide a mundane explanation. Watts fails even the dedicated amateur status on several fronts, some of which are in the article above, another is include approaching the problem with a clearly desired conclusion in mind, hence why I would not easily see him as a meteorologist.
  13. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Alan E "let's see a similar database for leading climate scientists who support the AGW hypothesis." If you have a look at the Interactive History tab on the top left you'll see that this is a major project just for the latest year. Let alone all years.
  14. Watts, Surface Stations and BEST
    To make sure I'm understanding all of this article properly, with regard to the differring properties of coating on Stevenson Screens. Aren't the different coatings irrelevant since we should be using the temperature anomoly rather than the absolute temperature? Like Watts I am not a climate scientist so I'd appreciate some guidance as to whether I'm grasping this properly. Unlike Watts I do hold tertiary qualifications, albeit in another field. (Sorry, but I couldn't resist)
  15. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Jim - you've done a great job - and I understand what you are saying about E&E (though i still think they are highly specious as a source of good science) - but, if you have the time, it might be worth looking at the citation index for each journal in which the "skeptic" papers are publsihed and compare that to the relevant citation index for mainstream climate science. I suspect I know what the answer would be. As I am sure you know one "measure" of the worth of a paper is how many citations it has scored. Just a suggestion.
  16. Watts, Surface Stations and BEST
    skywatcher: "I note that Watts is described as a 'meteorologist'. According to Sourcewatch, he holds no higher degrees or qualifications in the field of meteorology" Nor lower degrees, he dropped out of university after two or three years and never graduated. So, technically, he's a high-school graduate ...
  17. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Another thought ... let's see a similar database for leading climate scientists who support the AGW hypothesis. Notwithstanding the obvious arguments around bias against skeptic scientists by journals and research funders, it would be interesting to see the comparative level of contribution to the body of knowledge. Ta, Alan
  18. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Jim ... this window into the body of knowledge produced by dissenters of the AGW hypothesis is sorely needed ... thanks for working on it. A couple of thoughts: * I think the citations are important ... both the absolute number but also who cited it; down the track it may be possible to show what % of the citations were by later skeptic papers (in your focus population) i.e. to gauge whether the paper influenced other than other skeptics; although to gauge that reliably it would be necessary to assess whether the citation by a non-skeptic paper was a debunk or otherwise. * many of the authors haven't published in years and years; I'd like to see a simple indicator of "last published"; some of these authors haven't dissented in years ... are they still doing research? * I'd also like to see an indication of the papers that resulted from actual field research and analysis ... not meta studies or desk reviews of data sets produced by another research project; too many skeptic contributions are from people who do not have the deep understanding of the natural processes which 'real' climate scientists gain from many years effort Thanks, Alan
  19. Philippe Chantreau at 15:03 PM on 4 November 2011
    Watts, Surface Stations and BEST
    THese IR pics are very interesting indeed. Watts' site premise for existence has been invalidated by every data study ever intended to verify it: from the early work of John V, to Menne, to Fall. Now it turns out that his premise even lacks a physical basis.
  20. Watts, Surface Stations and BEST
    "We are the 97%" - AGW accepting scientists. Put that on a mug.
  21. Michael Hauber at 13:46 PM on 4 November 2011
    Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Should MM 2005 be included? It doesn't actually say anything about Co2 or global warming, but rather states that a particular reconstruction of the past temperature is not statistically significant.
  22. Watts, Surface Stations and BEST
    I note that Watts is described as a 'meteorologist'. According to Sourcewatch, he holds no higher degrees or qualifications in the field of meteorology, though he has been a TV and radio weatherman for many years. Of course anyone can do science provided they do it competently and read / comprehend the work of those before, but I wouldn't want people to confuse Anthony Watts with other professional meteorologists. His inability to understand the collection and processing of meteorological data, as shown by Patrick's excellent article and in many places elsewhere, is clear for all to see.
  23. citizenschallenge at 12:30 PM on 4 November 2011
    Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Jim Powell, WOW, what a great project ! ! Excellent, thank you, it will make a great resource. I'm looking forward to watching it develop and grow.
  24. Watts, Surface Stations and BEST
    oneiota: Here's a link for the Fall et al paper that should work
  25. Watts, Surface Stations and BEST
    Thanks for this. (I noticed that the link to the "Fall et al 2011" draws a blank at Word Press)
  26. Watts, Surface Stations and BEST
    This is lovely. As far as I'm concerned, this is the key quote: "Rather than draw readers' attention to the hot spots, I would invite readers to compare the color (temperature) of the instrument housing with the color (temperature) of the general surroundings. In each case, the temperature station casing is - despite being near a source of heat - at the same temperature as the nearby land." So Watts' biases can be demonstrated using his own photos.
  27. Climate's changed before
    280, lancelot, This isn't a normal venue. In a classroom, or a party, or at lunch, when you do as you describe you are right. But in climate change there are a large number of very, very arrogant, angry and ignorant people. They waltz in here with personal theories based on a gross misunderstanding of the science, stating everything from proof that the globe hasn't warmed to the idea that GHG theory violates the laws of thermodynamics and more. One (-self-snip-) even claims that he's proven that current warming is coming from the interior of the earth. Most people who comment here but do not already understand the science are not here to learn, or asking reasonable questions and looking for answers (as I presume you are). Most people who comment here but do not already understand the science instead have an axe to grind, and believe that they have all of the real answers, and that they'll show those dang, silly scientists a thing or two about logix and clear-headed thanking. Hence... a perfectly ordinary sounding question is likely to touch some nerves with people who have already been rubbed raw with what could, at best, be called a parade utter and complete nonsense. Hence, a sensitivity to such a response is advised. You might not want to go to the trouble to carefully word your questions, but you might give someone like KR a break when they presume that you are possibly asking these questions with a hidden agenda, hoping to trip people up or to sow doubt. At the same time... people here at SkS probably should back off and give newcomers a little more slack before flipping out on them.
    Response:

    [DB] "At the same time... people here at SkS probably should back off and give newcomers a little more slack before flipping out on them."

    Agreed.  Give the benefit of the doubt, with the action mentioned after the word "before" in your back pocket.

  28. Climate's changed before
    276 , by the way, amazing engineering, really fascinating to hear what goes on in deep ocean exploration. Was honestly interested in how one would could possibly know what happened 55mya and 7 miles down under the ocean. Impressive.
  29. Watts, Surface Stations and BEST
    Perhaps the final sentence would be clearer as: One must conclude from the lack of significant bias proven by multiple studies that the surface stations project highlights things which the casual observer thinks ought to cause bias, rather than highlighting factors found to actually cause bias.
  30. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    To make it easy for simple folk like me it would be good if the Takeaways could be classified somehow. Perhaps... a) Conclusions which genuinely seem to question threads of pro-AGW science b) Conclusions which have since been brought into question (with links) c) Conclusions that have been convincingly rebutted, preferably by peer-reviewed work (with links) I'm sure you can improve on my suggestion, but you get the idea.
  31. Climate's changed before
    Sphaeriica, if I make a statement, and someone says "how can you be certain?", I dont take offence. I explain why I feel confident in making the statement. So I don't quite see your point. KR please note the preface in my post 269. I clearly stated my ignorance at the outset, I quoted in full the basis for my question. Anyway, question raised, answer given, thanks for the scientific evidence which you have given to negate ocean floor heat release as a possible partial contribution to the PETM warming. Have you considered that every time some non expert says , maybe it isn't CO2, and you give a reasoned answer to explain why it is, it actually strengthens the public perception of the Co2 theories? Scaddenp will take a look, thanks,
  32. Climate's changed before
    Lancelot - have a look at this article here for more on PETM. The evidence for CO2 being culprit is in the ocean acidification which also constrains the size of change. I would also suggest looking at "Carbon dioxide forcing alone insufficient to explain Palaeocene–Eocene Thermal Maximum warming" Richard E. Zeebe, James C. Zachos and Gerald R. Dickens 2009 for an idea of the constraints (though I disagree with some of their conclusions).
  33. GHG emission mitigation solutions - a challenge for the Right?
    I rather sadly suspect that many (but by no means all) self-described libertarians are mostly concerned with their perceived rights and liberty, than the conflicting rights of their other citizens. If you have found your business or personal housing activities constrained by regulations, then it is easy to hear the drumbeat of libertarianism.
  34. Climate's changed before
    lancelot - Forminifera species ratios, sedimentation types/rates, isotopic balances, other signs. Forminifera species ratios are quite sensitive to environmental conditions, for example, and have been used to construct multiple paleotemperature records, including sea rise on the order of millimeters/year. And if the ocean floor heated up non-uniformly, the signs of such heating would be even more clear where it did happen. But seriously - there is no evidence to suggest a 5 °C heating of the ocean floor lasting 200 ka. That's the evidentiary equivalent of fairies, of claiming climate change is due to wars among the Mole Men, of magic wands. Actually reading Katz, Dickens, et al 1999, they state: "Long-term global warming during the late Paleocene pushed the ocean atmosphere system past a critical threshold, causing warm surface waters to sink and intermediate to deep ocean temperatures to rise by 4 to 8C. This warming propagated into the sediments, converting once solid CH4 hydrates into free gas bubbles. This dissociation resulted in an increase in pore pressure at depth, leading to sediment failure and the release of massive quantities of CH4 into the ocean." (emphasis added) From this they feel a circulation change pushed surface water quite quickly into the depths, warming the benthic waters and triggering the clathrate release. . "Methane release would have occurred on continental slopes ... adding carbon to all reservoirs of the global exogenic carbon cycle and substantially shoaling the depth of carbonate dissolution in the ocean. ... Over several hundred thousand years, global carbon and oxygen cycles gradually retumed to equilibrium conditions after the LPTM, although marine and terrestrial ecosystems were forever changed. " Again, note the carbon cycle disturbance. There are also in this paper descriptions of ocean cores that show sedimentation supporting this scenario. I would strongly suggest, lancelot, that you read the papers you have pointed to - it looks more like you're grabbing the first interesting quote without looking at the context, and hence presenting a misinterpretation of the work. There's a big difference between asking "Hey, somebody said XXX, I don't know if it's right or wrong?", and presenting skeptic arguments and (in this case) misinterpretations of papers as your opinion.
  35. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Troy, I have added Douglass and Knox GRL (2005). The abstract of MMH (2010) concludes: "In data spanning 1979-2009, the observed trends are significant in some cases but tend to differ significantly from modeled trends." This did not seem to me to step over the line into directly calling human-caused global warming into question. A judgment call. Spencer and Braswell (2010) say, "These results underscore the need for more accurate methods of diagnosing feedback from satellite data and for quantitatively relating those feedbacks to long-term climate sensitivity." Ditto. Forster and Gregory (2006) write, "There is preliminary evidence of a neutral or even negative longwave feedback in the observations, suggesting that current climate models may not be representing some processes correctly if they give a net positive longwave feedback." Again, "preliminary" and "suggesting" and "may not be" do not quite cross my threshold. As I said, my list is admittedly subjective and someone else might wish to count this paper and others that I do not. I believe that the import of this group of papers is the overall set of "takeaways." In the next post, I will present what I believe are those takeaways. I welcome suggestions for papers I missed, as Troy has done.
  36. Climate's changed before
    275, lancelot, Oh, and... a lot of real deniers come here trying to "trip up" the science by offering half-baked ideas that they assume scientists haven't considered. A lot of your questions come across in that vein, because of the way they are phrased. You'll probably raise less hackles if you take a little more care in how you phrase your questions, by making it clear that it's an honest question as opposed to a rhetorical question intended to convey doubt to lurkers (i.e. aimed at other readers rather than the people of whom you are asking the question). For example, your "how can you be certain..." question might be better phrased as "how have scientists ascertained that..." I know it may seem annoying, but it's important to come across as truly interested in the answers, and giving scientists their due respect, rather than making it appear that you have, in your spare time, out-thought the professionals and come up with something they can't possibly have considered.
  37. Climate's changed before
    275, lancelot,
    Just another question though, how can you be certain of "no geological signs" in the ocean floor from 55ma ago? Lot of sediment since then, and it's a big ocean.
    Research ocean cores. See how they are used to establish various aspects of climate, life, etc. See how they are dated (by looking at the different, distinct layers of sediment). For example, consider this excerpt about how cores can be taken:
    The Chikyu (Japanese for planet "Earth") seen above, cost $540 million and is a colossal 57,500-ton, 210-meter-long white ship developed to drill deep below the ocean floor. Besides being the most sophisticated laboratory on the seas, the science vessel boasts the tallest drilling derrick at 112 meters above the waterline and a drill pipe that is 9.5 kilometers long--22 times the height of the Empire State Building. The borer drills through 7,000 metres of crust while floating in seas up to 2,500 meters deep. Its drilling system uses a 380-ton protective casing over the wellhead that is about the size of a six-story office building. It shields the vessel against eruptions of methane gas and pressurized fluids and allows for the secure retrieval of nine-meter-long core samples.
  38. Climate's changed before
    KR, fine, I simply put what seemed to be a very obvious question, from a position which I had clearly stated, based on reading the statements quoted by Brian Lovell, and without the benefit of a detailed study of the PETM. The statements quotes were not backed up by detailed supporting evidence such as you have quoted. My question invited any rebuttal with contrary evidence, such as yours. That does not, I think, make me a narrow minded denialist. I may however be a bit persistent in seeking answers. Just another question though, how can you be certain of "no geological signs" in the ocean floor from 55ma ago? Lot of sediment since then, and it's a big ocean.
  39. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Thanks Troy. I will look into adding these papers.
  40. Climate's changed before
    Might I suggest to anyone reading this thread to to take the time and re-read Tom Curtis' post at #263. A great, and impotant post! And Tom, it might be worthy of a new blog post if the balance of both cold (LGM) and warm (PETM) climate sensitivity has not been explicitly covered before?
  41. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    When you say you are looking to include papers that "undercut human-caused global warming", I'm assuming you mean also those that argue for a lower sensitivity per doubling of CO2? I ask because many of the "skeptics" listed (e.g. Lindzen, Spencer, etc.) don't argue that humans don't cause global warming, but rather that the ECS is likely low. If that's the case, there are likely several more papers to be included. For example, the Douglass and Knox GRL paper (2005) suggests a low climate sensitivity (~ 0.6 C per CO2 doubling), but neither author has a paper included (not that I think this paper is particularly good). In fact, Douglass has quite a few papers that would be considered "skeptical" of global warming in this broader sense of the term, including those comparing modelled and actual temperature trends in the troposphere (GRL2004, Remote Sensing 2011, IJOC2007). I don't believe this is the same category as Klotzbach et al. (2009), as it directly calls into question the amount of warming projected by models. The DK2009 (Physics Letters A) paper that was referenced in Dessler 2011 argues that there is unlikely to be warming "in the pipeline". Anyhow, I found many of these on his UoR website if you want to peruse it to see which should be included. McKitrick, McIntyre, and Herman (2010) also have a paper comparing measured and modelled tropospheric trends, which seems more relevant to the topic of man-made global warming than the hockey stick work currently listed. The Spencer and Braswell papers (2008 JoC, 2010 JGR, and 2011 Remote Sensing) should also probably be included in the list, as they implicity argue for a lower sensitivity than that obtained in the original Forster and Gregory (2006) method (which was about 1.65 C per CO2 doubling) and pave the way for the Lindzen and Choi (2011) paper that is included. Anyhow, hope that helps as a starting point. I confess I haven't heard of many of the other skeptics.
  42. Berkeley Earth Surface Temperature Study: “The effect of urban heating on the global trends is nearly negligible”
    Sphaerica. Thanks. Not having the time to process data sets into Excel, I find visual tools useful to get a broad view, and as an architect, I tend to look for visual patterns first. Just to say, I made no adjustments to the actual form of the graphs. What is interesting is how compressing them horizontally accentuates rises and falls. I was surprised to see the steep lines up to 2000 in both solar activity and irradiance, roughly corresponding to the steep rise in global temperature. But I suspect that is no more than a visual impression. Tom Curtis I will more carefully check the solar trace of the IPCC graph, your point is noted.
  43. Climate's changed before
    lancelot - As an addendum to my previous post: The Earth fully equilibrates to changed energy conditions in a fairly short time, geologically speaking (~500-1000 years, including deep oceans). The only way for a temperature change to last 200 ka is for either the input energy or the temperature dependent rate of outgoing energy (as per the Stefan-Boltzmann relationship) to be different - a forcing change. Hence your PETM "sub-ocean heating theory" would require a 200 ka 5C warming of the ocean bottom. There's no evidence for that, and in fact significant evidence against it (there would be considerable changes in ocean core data, for example). Whereas we have plenty of evidence supporting increased GHG effects, including the timing of CO2 recovery matching the end of the PETM. Follow the evidence, lancelot - not your preconceptions.
  44. Climate's changed before
    lancelot - It takes something like 0.5-1 ka (thousands of years) for the deep oceans to equilibrate to a temperature change. The PETM event, quite possibly driven by a massive clathrate release, lasted 20 ka, with the effects persisting for 200 ka - plenty of time for the enhanced greenhouse effect to equilibrate. Not extra heat at the bottom of the ocean - we would see the geologic signs of that (volcanism, lava, etc?) quite easily. But a carbon release that increased the greenhouse effect. The extra CH4 (then oxidizing to CO2), massive GHG increase, leads to atmospheric and ocean surface heating, with ocean circulation bringing that to the depths. The math works out - no extraneous sub-benthic heat sources needed. --- I have to say that you appear to still be hunting for anything but CO2, rather than following the evidence. That's an inherent confirmation bias, searching for a particular explanation rather than paying attention to what the data supports. That attitude will lead you astray...
  45. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    One of the 'heros' of Merchant of Doubt, Fred Singer's comments appear to be given more attention than I think are justified. Zero peer reviewed papers! Actually his comments deserve no attention whatsoever. Hm, he's one of the 'scientists' who supported the tobacco industry (nicotine isn't adictive, really!) and didn't believe ozone depletion was caused by CFC's.
  46. GHG emission mitigation solutions - a challenge for the Right?
    The right to individual liberty of action providing it does not infringe on the rights of other rights-respecting citizens. This is a fairly accurate description of the central ethos. Unfortunately, it rarely seems examined by those who self-identify as libertarian. For instance: If a person has a right to run a business, isn't this right compromised by another business engaging in predatory pricing? Preventing that requires acknowledging that free markets aren't the pinnacle of human endeavour. As another example, polluting clearly violates the ethos, yet I sure don't hear about many libertarian environmentalists.
  47. Berkeley Earth Surface Temperature Study: “The effect of urban heating on the global trends is nearly negligible”
    38, lancelot, Let that be a lesson to you! Do things with the numbers, and let applications generate entirely correct graphs. You'll find that the data for most things is readily available on the Internet (scientists share a wealth of data openly, if you know how to find it), and Excel is fine for pasting in the data and generating a graph [although I must shamefacedly admit that this is exactly what I did to do the overlay on your graph -- I quickly took the Solanki graph from the paper to lay it over yours]. It's way to easy to eyeball things incorrectly even when reading a graph, let alone creating one, let alone creating one by merging other graphs with uncertain sources. I'm not sure what to say about the Wikipedia graph. The source appears to be the data from IntCal04 Terrestrial Radiocarbon Age Calibration (Reimer et al, 2004) with the supplemental data available here. I'm unsure why this data does not match Solanki et al 2004, except for the obvious, which is that Solanki used the INTCAL98 dataset, while Reimer created the INTCAL04 dataset, although the two do not look that drastically different (except the 04 dataset obviously must go beyond 1895). But without digging into it, I'm unsure of why the INTCAL04 data (or, at least, the Wikipedia graph supposedly based on the data) puts the medieval maximum so close to the modern maximum when the Solanki graph clearly does not, or where the data past 1895 came from, or why it lacks the drops evident in the 10Be data. I do note that the Wikipedia graph rather incorrectly labels 1950 as the "Modern Maximum" (*laughs*). My gut tells me that the person who created the Wikipedia graph did not understand how the calibration data was represented (it represents a % deviation from the standard 1950 level) and so scaled it improperly, leading to the seeming match between the MWP and 1950 levels.
  48. Climate's changed before
    lancelot - if you want to get into ideaological matters, how about taking the challenge here?
  49. Climate's changed before
    Moderator: Is there any way to find one's past posts? I am getting a bit lost with the many different threads.
    Moderator Response: [Dikran Marsupial] The easiest thing to do is to look back through the recent comments. However, it is generally a good idea to limit the number of discussions you participate in simultaneously. Science is best discussed in depth rather than breadth (at least to begin with), the best way to do that is to conduct a single narrow thread of discussion at a time and avoid digreessions.
  50. Climate's changed before
    Tom Curtis: Thanks for your post 263. PETM is a big subject area in its own right and I have yet to venture into it in depth. With my usual Sherlock Holmes hat on I would just ask, have all other possibilities first been eliminated? What little I know of PETM comes mainly from Bryan Lovell in 'Challenged by Carbon' (a book kindly recommended to me by Prof David MacKay) in which Lovell selects the PETM event of 55 Ma as the prime evidence for CO2 warming. To quote him: _________________________________ Prof G Dickens [presumably Dickens G R 1999, Nature, 401, 752-755] ... reaches several conclusions: 1 The first of their conclusions is that a large quantity of carbon was released into the ocean-atmosphere system 2 The second is that the temperature of the water at the bottom of the ocean increased rapidly by more than 4 deg C from 11 to 15 deg C , over the same short period. Norris & Rohl [1999] conclude: 3 For just a brief period, .. temperatures at high latitudes and in the deep oceans soared by 5 - 7 deg C. [some contradiction of numbers here] _____________________________________ I have not read the papers cited, but just considering those two factors as described, the primary event seems possibly to be heating of the bottom of the deep ocean. CO2 could not cause such a rapid effect directly. It seems very possible from those statements that a major geological event in the mantle or crust under the oceans released a large amount of heat directly into the deep oceans. A huge release of carbon from the mantle or crust in form of methane at the same time is indicated. Heating of the deep oceans would lead to a rise in air and surface temperatures, as well as a further release of stored CO2 in the oceans. No doubt the airborne CO2 would create a serious GHG effect, but how much of the surface warming could have in fact been caused by deep ocean water warming? Would that affect the sensitivity estimate? I hope I am not just saying 'yeah if', but putting forward a valid question here.

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