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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 71801 to 71850:

  1. Not so Permanent Permafrost
    Agnostic Typo in the para just below figure 2 ? "showing coastal erosion over the 30 years 1986-2005"... presumably either 20 yrs, or 1976? Nice post - but I wonder if there is enough clear emphasis on the frighteningly high GHG effect of CH4 before it oxidizes.. DaveW
  2. Clouds provide negative feedback
    Sphaerica (RE: 217), I don't think you understand what net negative feedback means. It does not mean that no long-term change can occur (or even short-term change). It means the response to changes in 'forcing' or energy imbalance will be to oppose or diminish those changes rather than re-enforce or amplify them.
    Response:

    [DB] Sphaerica quite well understands both positive and negative feedbacks, including those "net" ones.

  3. Bad, Badder, BEST
    'Well Duh!' indeed! More great work from Mr Sinclair. In a more sane and just world he'd be the one attracting the billionaires' funding...
  4. Not so Permanent Permafrost
    In the interglacial before this one, the Eemian, temperatures in Northern lattitudes reached temperatures higher than they have so far. I would expect considerable amounts of permafrost to have melted and released methane. Since the temperature change was slower than what we are experiencing I would expect methane might have been oxidized quickly enought to prevent any major spikes in its concentration. Still knowledge of what happened then should give us some idea of what is required before methane release reaches a tipping point. I would think that any tipping point depends not just on the temperature reached but on how quickly it is reached. I was not reached in the Eemian. What contraints does this put on the requirements for a tipping point now?
  5. Not so Permanent Permafrost
    dorlomin Data gathered 2003-08. See Shakhova et al 2010. Methane has a global warming potential of ~70 over 10-15 year period during which time it normally oxidises in the atmosphere.
  6. CO2 has been higher in the past
    55, cjshaker, At the top of the page you will find a link labeled "Comments". If you click it it will take you to a search page of all of the comments posted, in reverse chronological order. Most people will include your name or handle in a direct reply to you. Hence, it is easy enough to use a browser search on that page to find any comments directed at you. If you take a while between visits, you may also have to scan the 2nd or 3rd page of comments, but it really only takes a moment. I do it all the time. I also tend to keep track (in my head) of the threads where I have left comments and expect answers. I also have to second Albatross' analysis of your most recent comment. It's another drive by shooting, popping off unsubstantiated allegations and showing a gross misunderstanding of how things work ("supposed to shut up and let climate modellers..." -- where does that come from?).
    I am a computer scientist, not a climate scientist.
    This suggests to me that you have a lot to learn about climate, then, and would be far better served reading and learning than randomly posting. It seems that for you communication is a one way street.
    It is very easy to get the impression that climate scientists don't want anyone questioning their assumptions, beliefs, code, data, nor science.
    That's utterly absurd. If you read the comment threads here, instead of simply posting and running, you'll find a lot of healthy, engaged and high level debate. No one is remotely close to demonstrating the behavior you describe (although you'll find that people who do actively work to derail discussions and troll threads tend to complain a lot when they get properly moderated). You sound like someone who made up their mind before you got here.
    I've had one person call me a 'link bomber' before...
    Perhaps you should stop to think about this. Look through the comments both here and on other sites, and see how many people have posting behaviors that mirror your own, and how their comments are received. This site exists first and foremost to provide information to laymen about climate science. That John Cook provides comment sections for intelligent discussion is his choice, not a requirement imposed on him by society or "Internet law." It is also moderated to keep that discussion intelligent and focused, which is also his choice. This site is neither an open forum for anything anyone wants to say, nor run by climate scientists to promote an agenda. It is about science, but a certain decorum, engagement and behavior is expected from everyone to make any interactions both informative and worthwhile.
  7. CO2 has been higher in the past
    Hi Chris @55, "It is very easy to get the impression that climate scientists don't want anyone questioning their assumptions, beliefs, code, data, nor science." " it is very easy for the layman to get the idea that he or she is not to ask questions about climate science. We're just supposed to shut up and let climate modelers tell us how we should live our lives." I'm sorry that is your impression. It is, however, the incorrect impression. I'm also pretty sure that no matter how open and transparent we scientists are it will not be enough in your opinion. If you want access to the code and data, here is a good place to start, and while you are make queries, perhaps you could ask Spencer and Christy to release their latest version of their code for the satellite data. For the record, no climate modeller that I am aware of is telling us to "shut up" or telling us "how we should live our lives". That is an inaccurate and unfair characterization, it is also off topic. And climate science does not involve a "belief" system, but a synergy of chemistry, physics, mathematics etc., in addition to data. Such rhetoric that you are engaging in is not helpful, not constructive and not conducive to encouraging people to assist you. Regardless, you seem to be ignoring the fact that people have been politely answering your questions here, but that you seem to be ignoring their answers. Your question @51 seems to pertain to the carbon cycle and weathering of rocks, and Dikran @52 explained as much, s/he even provided a couple of helpful links. I do not understand how then you managed to arrive at your assertions quoted above. All the best, Albatross
  8. 9 Months After McLean
    So McLean's website states that he's a "computer consultant and occasional travel photographer", but no matter. He is a "climate realist" after all, and published with Bob Carter another "nail in the coffin of manmade global warming" or what not. His arguments deserve scrutiny. His website has lots of cute blurbs, some of them highly ironic. "The science simply does not add up, predictions do not match observations and the whole issue is loaded with a huge number of unproven assumptions, distortions of facts and outright lies." McLean on global warming Predictions...or...projection?
  9. CO2 has been higher in the past
    So a graph showing the trend of declining CO2 over the past 160 million years is not applicable to 'CO2 has been higher in the past'? And asking why the CO2 declines over time is not a question I should ask? It appears that Geologic processes bind the CO2 into rock, if I understand the previous answer correctly. Is there some way to subscribe to updates to only the questions that I have posted questions or links on? I do not have time to wade through emails of all updates to all questions on this website, but I am interested in updates to the questions in which I have posted. Given attitudes like this, it is very easy for the layman to get the idea that he or she is not to ask questions about climate science. We're just supposed to shut up and let climate modelers tell us how we should live our lives. I am a computer scientist, not a climate scientist. It is very easy to get the impression that climate scientists don't want anyone questioning their assumptions, beliefs, code, data, nor science. Thank you, Chris Shaker
    Moderator Response:

    [DB] Let us start off on the right foot, then?

    Welcome to Skeptical Science! There is an immense amount of reference material discussed here and it can be a bit difficult at first to find an answer to your questions. That's why we recommend that Newcomers, Start Here and then learn The Big Picture.

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

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

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

    "Is there some way to subscribe to updates to only the questions that I have posted questions or links on?"

    My suggestion, if you cannot come back here often, is to bookmark your comment by right-clicking on the time stamp (sorry, not a Mac user) and selecting the "bookmark this link" option. I would also put those bookmarked links into their own folder, such as "SkS Saved Bookmarked Questions" or somesuch.

    "We're just supposed to shut up and let climate modelers tell us how we should live our lives."

    At SkS we try to focus on the science and leave tone and suppositions (and projecting of suppositions) out of the dialogue.

    "It is very easy to get the impression that climate scientists don't want anyone questioning their assumptions, beliefs, code, data, nor science."

    If climate scientists didn't want anyone questioning their work, code (all freely available, mind you), etc, then why would they donate their time to write up blog posts for this website and then spend many hours interacting here and answering questions? Furthermore, every single climate scientist I have ever reached out to and contacted for help has literally bent over backwards in their efforts to be of service. Without exception.

    To get the most out of your Skeptical Science experience, follow the advice given above and by Sphaerica and Albatross below, and thank you for plying the SkS airwaves.

  10. steve from virginia at 09:01 AM on 26 October 2011
    9 Months After McLean
    Yikes! That's embarrassingly wrong. Arguing with your wife wrong. Beat your dog 'til it howls wrong. Mustache on the Mona Lisa wrong ... He must have been looking at last year's BP stock chart ...
  11. CO2 has been higher in the past
    53, cjshaker, If I may, this is not your blog. The sort of comments you are posting are the things someone might do on twitter or their own blog. To simply use SkS as a conduit for making your own drive by posts is not commenting, it's spamming. You also do ask questions. What is the point of questions if you never look for or pursue the answers? The appearance is that you want to give the illusion of engaging in discussion without actually doing so. That lends to the idea that you are using the popularity of SkS to push your own message without contributing in any way to the dialogue of the site. Which, again, is equivalent to spamming.
  12. Ice age predicted in the 70s
    In response to Dikran Marsupial: It seems that asking questions and then thinking about the replies is a problem? Chris Shaker
  13. Ice age predicted in the 70s
    In response to CBDunkerson, did I misread 'Extrapolation of the solar-output model shows a return to little-ice-age conditions by A.D. 2400–2900', ie - a couple of hundred years from now? Chris Shaker
  14. CO2 has been higher in the past
    I posted articles that I found while discussing climate issues with my friends on Facebook. I don't have time to read this website every day, and posted the sources and questions that seemed like they would be interesting to others. I've had one person call me a 'link bomber' before, and he also falsely accused me of not having time to read all of the articles I posted. I read them before, and argued about some of them before, on Facebook Chris Shaker
    Response:

    [DB] Chris, it's not the posting of links and questions that is at issue.  It's the not bothering to respond to the answers you get which is the real issue in play.

  15. SkS Weekly Digest #20
    Albatross#6: Not to mention a clear case of missing-the-point entirely. The cartoon contrasts a three year science-based study vs. sitting on the couch and speculating. That's clearly not about Dr. Pielke, but it does hit close to home for some of the usual suspects. But I like the irony in the fact that the source is a website about understanding science!
  16. SkS Weekly Digest #20
    Hi muoncounter @5, Actually, I think that we have just been given a very good demonstration of how some people will choose to perceive something in a particular way if they think that doing so will benefit them, or if they think they can get some mileage out of it or if they think it will detract from their failings. Here is the link to the page the cartoon was sourced from, it is titled "Beware of false balance: Are the views of the scientific community accurately portrayed?" The case being made in John's Weekly Digest is very clear, and the problem being highlighted is obvious to anyone following this sad "debate" about AGW in the media.
  17. Not so Permanent Permafrost
    In Figure 2, the reduction in "area with near-surface permafrost North of N45" is about 2 million sq km between 1915 to 1925 decade. That is about the same loss from the entire 1925 to 2000 period. What happened back in 1915-1925 to cause the rapid loss of 2 million sq km?
    Response:

    [DB] Figure 2 is derived from this study.

  18. Climate's changed before
    GCRs do not prompt emotive reactions. People who claim GCRs are the solution to all their climate change problems, without the benefit of legitimate analysis, prompt emotive reactions.
  19. SkS Weekly Digest #20
    albatross#3: Considering the cartoon containing the reference to 'Roger' comes from the UC Berkeley teaching resource website Understanding Science, dated 3 Jan 2011, we just got a pretty good lesson in how misconceptions form and propagate.
  20. Climate's changed before
    Sphaerica, Thanks again. My background is building and engineering, which tends to rely on fairly precise calculations, hence my expectations for precision. Your point is well taken that Climate is never going to oblige my personal wishes by making itself easy to quantify. As for 'must be Co2' I take all your points; the SkS intro on that might benefit from some re-phrasing, to avoid possible misunderstandings by others about the 'thought processes'. I do see that certain words such as G*R prompt emotive reactions. Not a reason to jump on the speaker please. I am not a climate scientist,I rely a lot on pre-digested reports. I see no reactions to the idea of micro-organisms having a role in cloud formation. Maybe grasping at straws with that, and surely way off-topic. But I am currently involved in supporting research into micro-organisms in the air and in precipitation, so I take a keen interest. Maybe we can breed some bugs to seed clouds and cool the planet? (Just half-serious on that one) Thanks for taking the time to respond in such detail.
  21. 9 Months After McLean
    Excuse 9: Did I say 2011? I meant 3011!
  22. SkS Weekly Digest #20
    Hear, hear, Albatross! Skeptical Science goes to great lengths to actually regulate the tone of posts & comments, so it is very disappointing to see Dr Pielke tone-trolling SkS on his own blog, all the more so in light of his own characterizations of his peers and the characterizations undertaken by Watts and company.
  23. The BEST Kind of Skepticism
    Inconsistency, that's the word. Watts Up With That Inconsistency? Straight to the point, Bert.
  24. SkS Weekly Digest #20
    Dr. Pielke , Please remove the following error from your recent blog post: "which, the disclaimer to the contrary in one of the comments, clearly is intended to relate to me " How on earth can you state that unequivocally? You claiming that "clearly is intended to relate to me" is simply false and you have been told so repeatedly, yet you insist on making this fallacious assertion and repeating it in public. I'm sorry, but we have many other issues to address besides you, and the cartoon was not about you. Four things Dr. Pielke, 1) There are many, many people who share your name on this planet, 2) Unlike the person in the cartoon, you are not a couch potato, you are a respected scientist 3) Unlike the person in the cartoon you are not opining about an issue which you are not qualified to speak to, in the case medical research 4) The message of the cartoon, to me and most reasonable readers for that matter, is very clear-- people speculating and speaking to things that they are not qualified to speak to (like climate science) is very annoying, and it also speaks to the media giving false balance to non-experts and contrarians. In my opinion, that someone has to spell this out to you (again) is ridiculous. Or are you calling us (and John Hartz) liars? Speaking of which, you should not be lecturing others (based on faulty interpretations) on etiquette when you post things like this on your blog when specifically referring to Dr. Tom Karl and the EPA. Do you consider that respectful and constructive treatment of your peers? This is how you recently described Dr. Jay Fein and Dr. Margaret Cavanaugh when you claimed that they ignored your requests (is the little girl meant to represent Dr. Margaret Cavanaugh?). Do you consider that respectful and constructive treatment of your peers? your friend Anthony Watts recently posted this delightfully defamatory cartoon of Dr. Muller and the BEST team (which then also refers to his co-authors, which includes a Nobel laureate). Do you consider that respectful and constructive treatment of your peers? Will condemn that action by Mr. Watts or will you tacitly endorse it? And this is how anthony Watts depicted the much respected Dr. Andy Dessler recently. Do you consider that respectful and constructive treatment of your peers? Should I continue?
  25. Not so Permanent Permafrost
    Just a note: All of the links in this article (Not so Permanent Permafrost) appear to be broken to me. The external links seem to have had skepticalscience.com prepended to them.
    Response:

    [DB] Fixed links (all of them, I think).  Made all graphics expandable (if larger scale available).

  26. Not so Permanent Permafrost
    Should have read "8 gt of carbon dioxide"
  27. Not so Permanent Permafrost
    If humans currently emit 29 gt of CO2 http://www.skepticalscience.com/human-co2-smaller-than-natural-emissions.htm CO2 has an atomic mass of 44 while CH4 is 16, that would decompose into 8 gt of carbon, so it would actually be a pretty significant addition to the CO2 in the atmosphere given its relatively short life as CH4? Sorry thnking out loud.
  28. Not so Permanent Permafrost
    Ah so that where this 3gt figure from Shakova came from, long term (late century) figures. Someone got their hands on it and was trying to tell all who would listen that this was the current measured figure and spinning all kinds of woe from that figure.
  29. 9 Months After McLean
    Excuse me, excuse 8, and imposter. Even more so.
  30. 9 Months After McLean
    I like excuse 9. Impersonation. Yeah, impersonation of a scientist.
  31. Linking Extreme Weather and Global Warming
    Re #240 (the new PNAS) study. I am so glad that someone did a proper attribution study, the results are quite sobering. Hard to fathom that July's in Moscow are warming at >5 C per century there, and that is summer when the anomalies tend to be smaller. Very interesting to read about how the GISS correction for the winter urban heat island is swamping the signal in the summer months. That paper deserves its own post IMHO.
  32. Linking Extreme Weather and Global Warming
    Very impressive shots Daniel, love those reds!
  33. The BEST Kind of Skepticism
    Thanks Bert, and I also agree with your assessment. The counterfeit dollar bill analogy is a good one.
  34. 9 Months After McLean
    Yeah, Figure 1 really shows that the norm now is much warmer than the norm 50 years ago.
  35. Climate's changed before
    234, lancelot, Forgive muoncounter for bristling. GCRs are a touchy subject. The fact is that the potential mechanism has always been taken seriously to some extent, but the mechanism is proposed, but still vague and unproven, some poor papers have used bad techniques to try to prove correlations that did not exist, there are no matching temperature changes to pair with identified major cosmic ray changes in the paleoclimate record, and most importantly there are no recent cosmic ray changes to parallel the temperature changes we've seen. This is not new knowledge. These things we've known for a decade or more. Still, the idea was never dismissed out of hand, and still isn't. It is being given its due, and researched as far as is worth the effort. But it has never been a serious "contender" to explain the warming trend because of the long known issues just described. But as muon said, there are other posts and threads to discuss that. We don't want to drag this thread any further off topic (which is another habit here at SkS... people like to keep threads focused, rather than wandering all over where ever the conversation decides to go).
  36. Climate Change Demands New Decision-Making Strategies by National Leaders.
    noble_serf: The US space program (Apollo) was hardly a small group effort: At its peak, the Apollo program employed 400,000 people and required the support of over 20,000 industrial firms and universities. For another, look at the Netherland's response to catastrophic flooding in the 1950s.
  37. Climate Change Demands New Decision-Making Strategies by National Leaders.
    3/4, noble_serf,Sphaerica isn't the best place to look things like CFC and the Montreal Protocol? Other places industry and government have got its act together; - The ITU - global spectrum management, telecoms protocols. - Comprehensive Test Ban Treaty (only a few rogues) - international shipping (most national waters respected) we're perfectly up to the job... when the interests of people, the markets and vested interests line up. It's a question of getting big-oil/coal to adjust their business plans... if they weren't so short-termist and wanted their businesses to last 100s rather than 10s of years... they might be happy with emissions reductions.
  38. Climate's changed before
    lancelot#234: "... assured before a lynching that all other suspects have been fully checked out first!" Odd statement. What makes you think that climate science doesn't work that way? If there were other reasonable candidates for causal agents, who wouldn't be checking them out? "GCR/ cloud forcing theory seems to have some credibility in the scientific community, and certainly looked like a good suspect to me for a while." Now there's an example of the thinking process you seem to feel is out there. There are many whose first principle is 'it can't be CO2' and therefore climb on to any bandwagon that happens to pass by. GCR threads are plentiful here (use Search), so I won't go off topic any further than to say that this idea had neither a reliable mechanism nor a reliable history and yet it still gained traction among the 'skeptics' - because it wasn't AGW. A fine example of not fully checking things out before making a lot of extravagant claims.
  39. Climate Change Demands New Decision-Making Strategies by National Leaders.
    3, noble_serf, The Great Depression. Rebuilding Europe after WW II. Rebuilding the South after the Civil War. The U.S. Interstate Highway system under Eisenhower. The taming of he American Frontier (not the kill-the-Indians part, but the rest of it, the economic and social aspects). The elimination of small pox and polio. You're not going to find much that matches our current dilemma, however. The fact is that true "global" interaction has really only been a reality for the past 75 years. The opportunity has not existed, nor the challenges presented themselves, to prepare us for what we need to be able to do today. It's all on us.
  40. The BEST Kind of Skepticism
    @Bert writes: "It seems to be trying to be the devil's advocate that pulls evidence out of thin air." An apt summary, Bert! I find I can't look at that site for more than a few minutes without my blood pressure rising to unsustainable levels. I have to visit SkS just to calm down and remind myself that there is logic to the world.
  41. Climate Change Demands New Decision-Making Strategies by National Leaders.
    More of a question than a comment: Other than war, when is the last time a national leader (or body of leaders) in major democracy has taken on a massive challenge and compelled people to take action and overcome a problem together? I'm looking for recent examples in history. The US Space program comes to mind, but it was a small group of people who were well funded. (Small group does great things rather than everyone in a large group doing small things.) Any other examples?
  42. Clouds provide negative feedback
    RW1 - "Then can you explain how the current energy balance is maintained despite such significant amount of shorter-term, local, regional, seasonal hemispheric and even sometimes globally averaged variability?" Conservation of energy, RW1. Internal variation produces lots of fluctuations, but such excursions up and down are limited by the incoming/outgoing energy levels, and will cycle around those energies. And of course, if the amount of energy in the climate changes due to (for example) increased GHG's, the climate will shift it's average behavior accordingly. As to feedbacks, as long as the gain < 1, the system is stable, as per the Does positive feedback necessarily mean runaway warming thread. Net positive feedback means a greater shift in climate state for input/output energy changes - not instability. And positive feedback is observed from the ratio of paleo changes in climate to reasonably well known energy changes, QED. --- RW1 - This has all been discussed with you before, in excruciating detail, on the Lindzen-Choi threads. Your continuing intransigence indicates (IMO) that your opinions and preconceptions are apparently more important to you than the facts.
  43. Clouds provide negative feedback
    214, RW1,
    Yes. It's interesting that you would mention this because it leads into my next point, and that is the physical processes and feedbacks that maintain the planet's energy balance cannot be separated from those that will act on additional 'forcings', such as GHGs.
    Good for you. You are beginning to demonstrate some grasp of how the system operates. Now your questions have been answered. You need to answer some of the questions that have been posed to you, specifically: With a net negative feedback, how do you account for the broad fluctuations in climate that have been identified throughout recorded history (through proxy studies)? And With a net negative feedback, how do you account for the dramatic and historically unique warming of the past 30 years? Why has your powerful net negative feedback not succeeded in constraining temperatures for the past thirty years? If it has not done so in that time frame, how can you imagine that it will do so in the future, as we continue to raise CO2 levels to dramatic extremes?
  44. Linking Extreme Weather and Global Warming
    Wow!, those are some awesome shots there Yooper.
  45. Clouds provide negative feedback
    213, RW1, Your original question was:
    Then can you explain how the current energy balance is maintained despite such significant amount of shorter-term, local, regional, seasonal hemispheric and even sometimes globally averaged variability?
    My leading question was:
    If you have a net negative feedback, why does the system succeed in fluctuating so greatly? Why does the negative feedback not keep the system stable and within very narrow confines?
    Your answer for my question was:
    Because the feedbacks take time and the system is largely chaotic.
    My answer to your original question is:
    Because the feedbacks take time and the system is largely chaotic.
  46. Clouds provide negative feedback
    Feedbacks need not be instantaneous. For instance, when wolves were shot in the early 20th century in order to increase the deer populations, herds increased immediately. However, the increase in the herds exceeded the carrying capacity of the environment, and the herds decreased over the next several years due to the lack of food supply. The herds varied widely initially, but were eventually constrained by the food feedback to a population which was not all that different from the original.
  47. Climate's changed before
    234, lancelot, Going bottom to top... Relative precision? He gave a range of 23% for known versus unknown forcings, leaving what I would consider to be pretty wide error bars in his estimates (even if the precision of the boundaries seems fine, the range between them is not -- scientists always use precise numbers to define embarrassingly imprecise estimates -- a science habit, I guess -- they like to be very precise in admitting to how much they don't know). What you term "unnaccounted for" by the models actually is accounted for, but it is not the result of ongoing forcings, but rather internal variability. No matter what we do, the system is still chaotic. Like weather, you are just never going to pin it down completely and make everything add up perfectly so that the model exactly matches reality on date X with temperature Y. It's just not feasible. What is more important to recognize, which is the core of your realization that today's CO2 truly represents a unique event in the planet's climate history, is that the temperature range being discussed for the 1,000 years prior to today's crisis covers a mere +/- 0.1˚C range on average and a +/- 0.2˚C range at extreme events. If close to half of that is attributable to known forcings, then in most periods only +/- 0.05˚C is "unaccounted for" and even in the extremes that number is only +/- 0.1˚C. And the greater swings are generally those that are accounted for by notable solar/volcanic events, which makes the real "natural variation" range very narrow indeed. I can't find a free version of the paper, but the figures and data area available here. Too, it is important to recognize the methodology and limitations that Crowley used. First, the inputs for solar and volcanic forcings for the past 1,000 years are themselves only estimates inferred from available proxies. Inputs for other variations, like ocean currents, land/albedo changes and such are non-existent, so what is left as "natural variability" could well have been accounted for with better inputs. Secondly, the temperatures against which he is comparing are also only proxy estimates, so the error range is by necessity broad. Who knows... it's possible that with precise solar and volcanic forcing inputs and temperature outputs, the accountability might be much greater. You have to consider the fog through which the scientists is attempting to squint to get to the inference. On to the last item, the "CO2 must cause" statement. The phrasing is unfortunate, but the take away message should not be "we can't think of anything else so the thought process stops here" but rather "everything we've tried does not account for the warming, and yet CO2 does." CO2 is not the culprit simply because someone saw it hanging around on the street corner the same night that today's Climate was murdered. His fingerprints are in fact all over the gun, and he was the only one with the key to the locked room in which Climate's body was found. What is unsaid on that page (and maybe it should be said to make things more clear) is that this conclusion was reached because models do incorporate every known forcing and none of them did the job. The use of every known forcing successfully models temperatures up to the current time. The dual implication of this is not only that CO2 appears to be the culprit, but also that if there were another, unknown forcing -- why did it never influence anything prior to the current dilemma? Where were similar dramatic changes in GCRs, solar activity and such for the last two thousand years? We know why there were no swings in CO2, but why no swings in any other magically hidden forcings? What's also left unsaid, as we have discussed, is that it is not like scientists then close their eyes to any other possible forcing. There are tens of thousands of scientists around the globe studying everything imaginable, from the Amazon to the Arctic to black carbon to land use changes to methane deposits to solar forces beyond our current understanding. No one is stopping their thought process and saying "let's focus on CO2 because it makes our job easier." Quite to the contrary, scientists would like to find, understand and pin down every forcing imaginable, because in so doing that 41% to 64% range that worries you drops to zero, all doubt vanishes, and the climate models become marvelously accurate. Such an accounting "benefits CO2 proponents" (as if anyone is a sports fan rooting for CO2 in a game) as much as anyone. By the way: Here at SkS it's considered bad form to use all caps (it's shouting). Instead use italics or bold for emphasis. You can click on the "Click for tips on posting images or hyperlinks" link just below the "Post a Comment" text box for instructions on how to do so (or just click this link here).
  48. Linking Extreme Weather and Global Warming
    Link to images of the aurora from last nite taken locally: http://www.facebook.com/media/set/?set=a.290369907653519.75544.165862740104237&type=1
  49. 9 Months After McLean
    Figure 1 is startling. I'm so used to seeing monthly variations overwhelming year-on-year variations, that a comparison to 50 years ago comes as a bit of a shock.
  50. Climate's changed before
    scaddenp: CH6 is indeed a great source. Thanks for reminding me.

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