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Comments 70951 to 71000:

  1. 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.
  2. 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.
  3. 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.
  4. 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,
  5. 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).
  6. 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.
  7. 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.
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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?
  14. 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.
  15. 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.
  16. 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.
  17. 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...
  18. 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.
  19. 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.
  20. 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.
  21. Climate's changed before
    lancelot - if you want to get into ideaological matters, how about taking the challenge here?
  22. 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.
  23. 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.
  24. Climate's changed before
    267 No, my apologies, I meant Total Surface Irradiation. Moderator: Point noted. My first use of graphics, possibly the last.
    Response:

    [DB] It is not the usage of graphics to make a point that is the issue (indeed, graphics are extremely powerful in conveying of complex information and ideas).  The issue in play is that the source of the graphic needs to be made transparently clear.  And if the graphic is "home-baked-bread" then the methods used to create it (the "recipe", if you will) must be made available to the reader as well.

    But thank you for providing the requisite information.

  25. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Monkey--Let me take a look at that. Good idea.
  26. Berkeley Earth Surface Temperature Study: “The effect of urban heating on the global trends is nearly negligible”
    Correction, the the two sunspot images are my screen snapshots, taken from the J Kirkby talk on CERN CLOUD, about midway. http://www.youtube.com/watch?v=63AbaX1dE7I
  27. Berkeley Earth Surface Temperature Study: “The effect of urban heating on the global trends is nearly negligible”
    Sphaerica: It is my chart, originally done for my personal interest when I first became interested in the subject some time back. The base graph is from Wikipedia here The Solar Activity graph is traced off this Wikipedia graph here . It was reversed, to run the timescale L-R, compressed horizontally but uniformly in Powerpoint then overlaid, with as good a timing match to the start and end timeline points as possible by eye. The vertical scale is distorted simply to show the correlation of shape, and hence an implied causal correlation. No more than that. The Solar irradiance line is traced off the IPPC AR4, Ch 9, fig 9.4 Matching to the timeline as above. Again the vertical scale is stretched simply to check for correlation of shape. Apologies for any inaccuracies, reasonable effort was made to make an accurate trace and time fit within the limitations of Powerpoint. The purpose was simply to check for any broad historic correlation between global temperature, solar activity, and solar irradiance. The broad correlation does seem apparent. Nothing more than that is intended by the chart. No values are associated with the vertical scales of the traces. If it is considered misleading, please feel free to have it deleted. As for the other 3 images, they are all from NASA.
  28. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    It would be useful if you could show the journal for each paper listed - it would give a clearer picture (i.e. are these papers in appropriate journals, or have they been slipped into low-impact journals on topics barely related to climate science? Excellent work though.
  29. Pielke Sr. and SkS Dialogue Final Summary
    Victull @ 62 - my bad. As far as ENSO is concerned we need to differentiate what we are talking about here. You (and Tristan) are quite right that ENSO is an internal redistribution of heat, and therefore cannot cause long-term warming (we happen to obey the laws of thermodynamics on this blog! - to paraphrase Homer Simpson). On shorter timescales, ENSO profoundly affects the global weather. La Nina causes cooling of surface temperatures, and El Nino warming. The bulk of this is due to the exchange of heat in the top 500 metres of ocean, and this is essentially the tilting of the thermocline in the equatorial Pacific. The effect is so large it is global in scale. But the key point is this: over 90% of global warming is going into the oceans, and La Nina is a time of strong ocean warming, even though the surface layer is cool. It's this surface layer that globally affects surface temperature, misleading the average punter into thinking that this "slowdown" in surface temps mean a slowdown in global warming. It isn't - global warming is still "Full steam ahead, both engines!" This will be covered in upcoming posts, because it's an area that's not really well understood by the public at large. But no. you can't treat ENSO as an external forcing because it isn't. The "cool" phases are eventually balanced by the "warm" phases, as heat within the system sloshes back and forth.
  30. Mythic Reasoning about Climate Uncertainty
    This myth lives on without end. Here is JCurry giving the Uncertainty Monster talk in Santa Fe, complete with graphics poking fun at various scientists and the very idea of consensus: Don't listen to what one scientist says. Listen to the consensus reached by over a thousand scientists. As if it is inherently bad when more than one researcher finds the same thing. Isn't that the way it's supposed to work? These folks continue to drag science down the drain. Then she makes her pitch for 'scientific integrity.' This was a dinner talk - hope nobody had to make a run for the exit!
  31. Climate's changed before
    265, lancelot, Sorry, I just realized that you used TSI incorrectly, and I responded to my instant interpretation of the acronym, not what you meant by it. TSI stands for Total Solar Irradiance, and has to do with the amount of solar radiation (all frequencies) hitting the earth at TOA (top of atmosphere). It does not refer to the amount of radiation actually reaching the ground.
  32. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    E&E might best be handled by another sort of 'footnote' like I had suggested for withdrawn arguments. That is, list the papers, but then note that there are reasons to consider the 'peer review' of E&E suspect. Err on the side of inclusion, but note factors which could reasonably have been used to exclude some things.
  33. Climate's changed before
    FYI, there is evidence on TSI... evidence that there has been no corresponding increase coincident with the warming of the last 30 years. That's why they started reaching for GCRs and other special effects. Except that there are proxies for that, too, and they don't appear to have had that sort of climate effect in the past, so why would we think they suddenly have a large effect now? And, lastly, if such an effect is large, then it implies a high climate sensitivity -- and a big part of the skeptic argument today has turned to a begrudging admission that it is warming (unless some new evidence says it's not or it's stopped), a begrudging admission that CO2 is the cause (unless some new idea says maybe it's not), but an adamant belief that any such warming will not be too great because climate sensitivity is low and the planet has a natural negative feedback to constrain temperatures to a narrow range (this despite the evidence of great swings between glacial and interglacial periods, and other proxy evidence of past extreme if much slower changes in climate, observational evidence of positive feedbacks in today's warming world, and well conceived and modeled mechanisms that would point to the currently estimated sensitivity of 2˚C to 4.5˚C).
  34. Berkeley Earth Surface Temperature Study: “The effect of urban heating on the global trends is nearly negligible”
    33, lancelot, Please answer my question here, but continue any discussion of the sun itself on another thread. I'm curious. What is the source of your solar activity and irradiance graph in comment 33? I mean, any number of sources will show you a very, very different record of solar irradiance and solar activity. The author of that graph is clearly guilty of extreme misrepresentation of the data. FYI, here is the actual solar activity reconstruction that was almost certainly the source of the data (based not only on 14C, as stated, but also two sources of 10Be and Group Sunspot Number), from Solanki et al Nature 2004. Note the down-tick in solar activity at the very end, too, from actual sunspot counts. Pay attention to the years... 14C dating ended 1895. 10Be ended around 1950. The graph ends 11 years ago at 2000. The rise in solar activity is from roughly 1900 to 1950, and does not correspond to the recent, accelerated warming. Here is that graph overlaid and scaled to fit with the graph you supplied. Clearly, the creator of the graph took great liberties in choosing the 14C proxy when it suited him, or the 10Be proxies or GSN proxy when they looked better, and even then he shifted things left, right, up and down to better match the temperature record. And then he left off the down-ticks at the end. Doesn't this annoy you just a little? Solanki et al 2004 is available here. An intelligent discussion at Real Climate can be found here.
  35. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    The trouble is, if you say E&E does not belong, then you are saying you are not going to rely solely on the WoS but are somehow going to decide journal by journal which belong and which do not. I presume there is a range of peer-reviewed practices among journals that make some better at it than others, but how to go back to say 1995 and decide that?
  36. Climate's changed before
    Sphaerica, no problems. You are right to curtail, but I am not running out of ideas. I had a specific list of questions, I have now gone through it. The topic question was: What does past climate change tell us about warming? Part of the answer would be: Identify all natural causes which may have caused warming, and which may still be causing warming. Once they have been carefully and rigorously eliminated, it leaves only AGW. The list of the 'possible others' was: 1 Solar irradiance - yes of course, but variations are not powerful enough to account for recent variations. 2 Does Solar activity/GCR influence cloud formation? Answer - perhaps, but no firm evidence for that theory yet. 3 Is cloud formation influenced by the biosphere? Answer - perhaps,some interesting studies in hand, but no firm evidence of a significant effect yet. 4 Earth heat, release of mantle heat underwater? Answer - no evidence. 5 Increase in surface irradiation (TSI) due to any other unknown cause, as yet undetected. Answer - the subject has been discussed in another thread. TSI data is incomplete and there seem to be no historic proxies. So, no evidence either way on that. 6 Fairies (joking) That was my entire list of 'suspects'. I have had clarification on all, for which many thanks to all. In summary, on the basis of current evidence: Past climate change and assessment of all conceivable natural causes tells me that AGW looks a 95% certainty. My point about bankers? Well, all professionals carry responsibility for their advice and decisions. I am one. I have to make decisions too, some of them determined by an assessment of the AGW case. If AGW predictions are correct, the world will be grateful for your advice. It not, the world will be quite unhappy about wasted resources. No judgment there, just the way life is. Good luck.
    Response:

    [DB] Here we are, a flurry of responsive comments later (all subsequent to your comment with unsourced graphics).  I remind you again of the need to provide sources for these asserted graphics as others having to point out the issues with these is dragging this whole thread off-topic.

    Or else I will have to clean up this thread a bit.

  37. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Jim... If you haven't seen this list you should check it out. I think the great information you're compiling here makes the most impact when placed in context to how much science is actually out there on climate change.
  38. Philippe Chantreau at 02:53 AM on 4 November 2011
    CO2 measurements are suspect
    Fitz, you can take a look at this. Concentrations in multiple bubbles are averaged, known events used for indexing, there is a variety of ways to ensure the reliability of measurements and extract the best data. It's another one of the things that real scientists have already worked on quite a bit. This paper from the Vostok team has a methodology discussion and a bunch of references, many on methodology: http://cdiac.ornl.gov/trends/co2/vostok.html
  39. Mercury Scientist at 02:34 AM on 4 November 2011
    Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    15, Mark: I agree. VERY generous. I would not call E&E a scientific journal. But we could get sued for saying that. :)
  40. Baked Curry: The BEST Way to Hide the Incline
    green: BEST's data ends in the spring of 2010. As the full year was tied with 2005 for the 2nd warmest on record and 2011 to date hasn't exactly been cool, when those data are appended, you may well be right. Let's see them spin that into 'no evidence that warming hasn't stopped.'
  41. Visual depictions of CO2 levels and CO2 emissions
    Excellent, cheers mate
  42. Pielke Sr. and SkS Dialogue Final Summary
    I was under the impression that ENSO can't be a 'forcing' because it's effectively zero sum. All it can do is create noise.
  43. Baked Curry: The BEST Way to Hide the Incline
    Being a bit pedantic. Due to very warm years 2000 to 2010 global warming is accelerating.
  44. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    This is a useful post and a great reference. But I think Jim is being VERY generous to include anything from E&E. In my opinion ANy paper in E&E is totally discredited. This link Why E&E is flawed articulates quite well the problems with E&E. It's a politically driven journal (self-admitted by it's editor), published more "skeptic" papers than any other journal by a very long margin, has peer review processes which have been seriously questioned, and has a citation impact factor around 0.42 - less than one citation every four years. Nature, one of the most central scientific journals in this field, has an impact factor of around 30. The Journal of Climate, a mainstream but smaller climate journal, has an impact factor of 3.57.
  45. Berkeley Earth Surface Temperature Study: “The effect of urban heating on the global trends is nearly negligible”
    Lancelot @33 and 34, the source of your first graph is trying to sell you falsehoods. Below is the IPCC graph from which the "irradiance" graph is derived (click on image for larger version): The caption reads:
    "Figure 9.4. Contribution of external forcing to several high-variance reconstructions of NH temperature anomalies, (Esper et al., 2002; Briffa et al., 2001; Hegerl et al., 2007, termed CH-blend and CH-blend long; and Moberg et al., 2005). The top panel compares reconstructions to an EBM simulation (equilibrium climate sensitivity of 2.5°C) of NH 30°N to 90°N average temperature, forced with volcanic, solar and anthropogenic forcing. All timeseries are centered on the 1500-1925 average. Instrumental temperature data are shown by a green line (centered to agree with CH-blend average over the period 1880-1960). The displayed data are low-pass filtered (20-year cutoff) for clarity. The bottom panel shows the estimated contribution of the response to volcanic (blue lines with blue uncertainty shade), solar (green) and greenhouse gas (GHG) and aerosol forcing (red line with yellow shades, aerosol only in 20th century) to each reconstruction (all timeseries are centered over the analysis period). The estimates are based on multiple regression of the reconstructions on fingerprints for individual forcings. The contributions to different reconstructions are indicated by different line styles (Briffa et al.: solid, fat; Esper et al.: dotted; Moberg: dashed; CH-blend: solid, thin; with shaded 90% confidence limits around best estimates for each detectable signal). All reconstructions show a highly significant volcanic signal, and all but Moberg et al. (which ends in 1925) show a detectable greenhouse gas signal at the 5% significance level. The latter shows a detectable greenhouse gas signal with less significance. Only Moberg et al. contains a detectable solar signal (only shown for these data and CH-blend, where it is not detectable). All data are decadally averaged. The reconstructions represent slightly different regions and seasons: Esper et al. (2002) is calibrated to 30°N to 90°N land temperature, CH-blend and CH-blend long (Hegerl et al., 2007) to 30°N to 90°N mean temperature and Moberg et al. (2005) to 0° to 90°N temperature. From Hegerl et al. (2007)."
    Assuming the creator of the graph has scaled one of the two reconstructed solar forcings (the green line and the dashed green line), then the uptick at the end of the graph as presented by you is incorrectly scaled. Indeed, for the dashed green line (the best fit on general shape), in the IPCC reconstruction the final values are lower than the initial value. Alternatively, the graph is based on the reconstructed temperature using all forcings (silver line, upper graph) which does indeed have the appropriate uptick, but is not a reconstructed solar irradiance. I will note that it is inappropriate to rescale one forcing as in the graph you presented without rescaling all forcings by an equal amount. Failing to show the other forcings cherry picks the data.
  46. Fred Singer Denies Global Warming
    I believe Roger Helmer is also the European reprepresentative of the Competitive Enterprise Institute and has spoken against AGW in a number of UK/EU right wing situations. Say no more
  47. Pielke Sr. and SkS Dialogue Final Summary
    Bob & Rob @59 &60 Sorry if my 'I guess' seemed cute. It is a result of Amero-Irish language exposure. I figure that you two are more expert than I am on these climate change topics, however I do have some background in heat transfer and thermodynamics. " Perhaps you took victull's statement as one indicating long-term averages" - right on Bob - that is the point I was making. Is not global warming all about long term averages rather than short term variations? If you would indulge maybe a slightly off topic area; I do have one more question for you which has been troubling me. Dr Pielke and others have made much of the slowing in warming over recent years and Dr Trenberth also refers to a stasis in warming. Aerosols, reduced Solar and ENSO - La Nina cycles are suggested as reasons. ENSO - La Nina cycles are usually considered as internal redistributions of heat which is already in the system. In that case they should not contribute to global heating or cooling. If that is not the case then why should ENSO - La Nina not be treated as external forcings just like Solar and Aerosols?
  48. Climate's changed before
    261, lancelot, 2 things. First, I'm getting the impressions from your posts that you're currently in a "yeah, but what if" mode. You are looking as hard as you can for alternative explanations, but you're starting to run out of ideas (as have the deniers/skeptics). This is fine, and the path you have to take to some degree. But you should be leery of resting a position on ignorance (i.e. it might be those impossible to define natural forcings, or just plain something we haven't thought of yet). That's not science, it's magical thinking. There is also a whole lot to learn. Molecular physics, atmospheric physics, how the myriad proxies work, past climate change events, ocean mechanics, how ENSO works, how models are constructed etc., etc. Your time would be much better spent studying what we do know rather than trying to pin down what we don't know in order to give a wave of the hand attribution of climate change to something other than CO2. The science is fascinating, in and of itself, and you will understand the gaps in our knowledge (where they are, and how deep) much better by learning what we do know than what we don't know. Second... apologies for having parts of your post snipped, but unlike WUWT and many other denial sites, we like to stick exclusively to the science. Occasional this rule must be bent because of current events or the topic of a post (such as public policy), but as a rule, physics doesn't belong to a political party or have a socio-economic reason for warming the planet, so those factors aren't worth discussing.
  49. Visual depictions of CO2 levels and CO2 emissions
    Tristan, further information on the GOSAT Observations (and the disinformation from Mr O'Sullivan) at The Blackboard.
  50. CO2 measurements are suspect
    I see a lot of comments that suggest that CO2 in the ice cores are not accurate because of the fixing of CO2 in the bubbles in the first place happens over decades so that flucuations of less than ~80 aren't recorded and then the interaction of the trapped air with the ice surrounding the bubble. I couldn't find an article that refutes this argument so I thought I'd ask it here. Would anyone care to comment on the accuracy of the ice core data?

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