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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 73501 to 73550:

  1. Climate Change Could be Expensive for Canada
    Jonathan (#7), There are fallacies in your reasoning. It's not so relevant what the current death rate is but how it changes in response to climate change. The study I linked (also cited by the report) indicates little change in mortality in winter months going forward in 3 Canadian cities. Similarly, what matters to energy costs is how they change over time, not what they currently are. Could be that heating costs are reduced more than AC costs are increased in a warming climate. It also could be that Canadian homes are built for heat efficiency, and so energy costs will be more sensitive to increased summer heating. I do think it would have been nice if they estimated changes in energy costs, but it's not clear to me which direction it would go. The report indicates that this is not meant to be the last word on the topic.
  2. Climate Change Could be Expensive for Canada
    Sorry to dribble… Obscure references deserve links, particularly on an international forum. Here’s a couple: http://www.vancouversun.com/business/Pipelines+coast+more+important+than+Keystone+HSBC/5453565/story.html http://www.marketwatch.com/story/canadian-crude-under-attack-on-two-fronts-2011-09-29
  3. Climate Change Could be Expensive for Canada
    Add to #8: And if we Yanks don't get our XL straw to suck it all up with, Canada seem all to willing to sell it to China.
  4. Pielke Sr. and SkS Disagreements and Open Questions
    Water vapor is a feedback while we're discussing forcings, so that's not the issue. I think it's mostly that Dr. Pielke thinks the black carbon forcing is underestimated, and possibly methane as well. I discussed this in 'CO2 contribution' section.
  5. Modern scientists, following in Galileo’s footsteps
    Question for all: What should be the #1 point to make in an SkS "basic" rebuttal (this rebuttal is "intermediate")? i.e. Given just one shot, what is single succinct " killer" argument you would use to puncture the Galileo Gambit? My original draft "brief rebuttal" was simply this: "The comparison is exactly backwards. Modern scientists follow the evidence-based scientific method that Galileo pioneered. Skeptics who oppose scientific findings that threaten their world view are far closer to Galileo’s belief-based critics in the Catholic Church." Can we do better, in light of the comments above? Along these lines, Rational Wiki has a concise rebuttal to the "Galileo Gambit" (their term). The generic form is: “They made fun of Galileo, and he was right. They make fun of me, therefore I am right." The essence of their rebuttal: "There is no necessary link between being perceived as wrong and actually being correct; usually if people perceive you to be wrong, you are wrong. . . [nothwithstanding] the selective reporting of cases where people who were persecuted or ostracized for beliefs and ideas that later turned out to be valid." It's worth checking out, at http://rationalwiki.org/wiki/Galileo_gambit. It concludes with that delicious, but perhaps unuseful, Carl Sagan quote about Columbus, Fulton, the Wright Brothers.....and Bozo the Clown!
  6. Climate Change Could be Expensive for Canada
    Canada is in an interesting position. Not only do they consume carbon based fuel at a per capita rate comparable to the US, but they also sit on one of the largest resource of very carbon intensive oil. Short of producing oil from coal it is tough to beat tar sands for carbon intensity when it comes to mile driven.
  7. Climate Change Could be Expensive for Canada
    Albatross, If the earlier NRT report concluded that the pros outweighed the cons, why should we focus on this new report where the pros are omitted, and only the cons are listed? Even though Canada is better adapted to cold weather than many other counties, the death rate is still highest in the winter months. http://www.cmaj.ca/content/181/8/484/F1.expansion.html By the way, air conditioning costs in Canada cannot compare to heating costs.
    Moderator Response: [John Hartz] For better or for worse, SkS did not post articles on the first three reports produced by NRT when they were released. We encourage you and all other readers to peruse the entire set of reports. I will provide direct links to each of the first three reports as an addendum to the above article.
  8. Pielke Sr. and SkS Disagreements and Open Questions
    Forgot to finish that line of thought: The what-about-the-paleoclimate response to low sensitivity estimates has almost become a meme on the AGW side, but then, I've been seeing it for years, and I have yet to see a comprehensive response. IIRCR, Lindzen made an attempt, but it fell short of being globally applicable.
  9. Pielke Sr. and SkS Disagreements and Open Questions
    Angliss #1, IDK, but it is possible, I can't speak for any contributors to the exchange. In any case, water does not spontaneously decide to become vapor, or delay precipitating once thresholds are reached, and there is already plenty of it exposed to air; therefore, it is not a primary driver. It can only respond to and enhance warming or cooling around it. So, if Pielke is comparing water vapor with CO2, he is comparing a feedback with a forcing, and the discussion has been around primary forcings. CO2 can also be a feedback because a temperature change can alter the carbon cycle, but in this case we know we have added lots of gigatons to the biosphere; so, we know we have created a causative agent, and we can only hope that our cause does not trigger a strong feedback of itself. Dana, thanks for completing the flip-side of what you came to an agreement on. It's kind of anti-climactic for me, but not completing it would have been a gaping hole in the series. It strikes me that many in the denier camp cling to the proposition that AGW is only based on models because the models are complicated and never 100% right; so, they are easy to argue against. Whereas, the paleoclimate record is simple to understand, and it is hard to argue against the idea that, this is what the earth has done in the past, we can expect it to do something similar now.
  10. Dikran Marsupial at 04:11 AM on 1 October 2011
    2011 Sea Ice Minimum
    Bernard J. Here are some sea ice volume projections, they look a bit pessimistic to me, usual caveats about this being a purely statistical projection apply, YMMV. This gives the general shape of the projection: Focussing in on the near future: The periodic covariance function looks like a neat way to model the seasonality. prediction for 2012 = 4.342434 (+/- 2.071584) 10^3km^3 prediction for 2013 = 3.306950 (+/- 2.227936) 10^3km^3 prediction for 2014 = 2.211567 (+/- 2.426253) 10^3km^3
  11. Understanding climate denial
    cRR: The ability to change your stance like that is the essence of skepticism. Above all, we must remain skeptical of ourselves :) Stephen: You're right. The anti-CAGW/right-wing blogosphere is not representative of typical 'denialism'. In reality most people on both sides aren't well informed and will tend to the default position of whichever political team they're on. This puts undue influence in the hands of political leaders. The politics should be about addressing the problem, not assessing whether there is one (I thought we'd set up an independent international body to do that). The point you made about being non-threatening is very important. Derision and accusations incline people to commit further to their opposing view, rather than relax and listen to yours.
  12. Pielke Sr. and SkS Disagreements and Open Questions
    One quick comment (still digesting this) - SkS and Pielke Sr may be talking past each other on the CO2 thing. I suspect he's thinking of CO2 vs. water vapor, while you're not.
  13. 2011 Sea Ice Minimum
    40, Tom, 43, Dikran, I believe, however, that the "lower angle of incidence" theory presumes that incoming sunlight is a major factor in local warming/melt. I thought that it's been determined that the water temperature and not the sunlight itself was the main factor. Admittedly, the increase in local warming due to more exposed water due to more ice melt will still be lower (due to the lower angle of incidence), but if the main temperature of the water comes from heat being transported in from outside of the Arctic, then I would think that would low angle of incidence would be a minor factor. The bigger factor, in the end (I believe) will be flat out warmer water temperatures. Ten years from now, with the water that much warmer, everything will melt faster and more thoroughly, from start to finish. Eventually it will be so warm that it just overwhelms whatever ice is there. For that reason, I think that the end will come surprisingly quickly. [On the flip side, I do think the complete disappearance of the sun, dropping air temperatures to the point where things start to refreeze, is a major factor, and the fact is that the melt season is much shorter at the actual pole, so it may be a long time before the seas are warm enough to melt everything there before the sun sets.]
  14. Understanding climate denial
    One thing we've not considered is the role of the sociopath in spreading denial. People with sociopathic tendencies apparently make up 4% of the population. I can't help think sometimes that some of the most vociferous of those in climate change denial would come out very clearly in this questionnaire as sociopaths. I'd mention one famous touring 'sceptic' by name but I guess he'd threaten to sue me. And if that doesn't give you a clue to whom I refer, I don't know what would!
  15. Modern scientists, following in Galileo’s footsteps
    John R#40: "Being persecuted does not make you right," Let's not give those in denial a pass on that. Persecution? Really? Giordano Bruno was persecuted. Having to publish a paper (of dubious value) in a minor journal rather than in Nature doesn't come close. "any more than agreeing with the majority somehow makes you wrong." And yet you often hear that on the denial blogs. To agree with the majority position is said to have 'drunk the Kool-aid' or to be somehow incapable of independent thought. As if it is impossible to independently review the evidence and conclude that the majority opinion is correct. Example: The FT is drinking climate KoolAid -- by none other than our friend RPJr.
  16. Modern scientists, following in Galileo’s footsteps
    To be the "next Galileo", it is not sufficient that you be a maverick, that your theories are contradictory to the consensus, that you are laughed at. You must also be correct. That's a rather higher standard.
  17. OA not OK part 20: SUMMARY 2/2
    My apologies, Bernard J. - in my previous post I was mistakenly responding to the "acidification" portion, not the (quite correct) variation of neutral point. More caffeine needed, I believe...
  18. 2011 Sea Ice Minimum
    "Whether or not melting ice follows a Gomperts path, I suspect that it will follow one of the asymmetric sigmoids..."
    ...for the sort of reason that Dikran Marsupial mentions in the first paragraph of #38.
  19. OA not OK part 20: SUMMARY 2/2
    The last time I ran into the semantic issues with "acidification", I simply noted that: If you stand at the South Pole, then walk 100 meters in any direction, you are still in the Southern hemisphere. But, you have indisputably moved 'northward'. And 'acidification' is the term used for a chemical mixture moving towards acidity.
  20. 2011 Sea Ice Minimum
    Logistic curves are nice and easy, but they're symmetrical about the point of inflection, which is often quite an artifical assumption about natural processes. Of course, this is not to say that the shape of a Gompertz is not itself an artifical fit to certain sets of data (usually it is), but in various ecological contexts at least I've found Gompertz nearly always seems to better describe the nature of trajectories than do logistics, von B's, or other of the stable of sigmoids. Whether or not melting ice follows a Gomperts path, I suspect that it will follow one of the asymmetric sigmoids...
  21. Modern scientists, following in Galileo’s footsteps
    Tom Smerling @38, while I cannot speak for Einstein or Hawking, it is absolutely true that Galileo invented modern science with his detailed observations of bodies in motion. That, far more than his astronomical observations and writings marked a break with past practice and dependence on authority rather than observation as arbiter of knowledge.
  22. Modern scientists, following in Galileo’s footsteps
    Tom, les, The 'Galileo was persecuted, but right' meme should be paired with the 'just because it's the consensus doesn't make it correct' meme. They both spring from the same cherry-picking of history and both are very popular with those in denial. Being persecuted does not make you right, any more than agreeing with the majority somehow makes you wrong. And, by definition, once you've been proved right and everyone suddenly agrees with you, you're in the consensus; and then it's those that don't agree with the new consensus that suddenly become the mavericks. What makes someone either a 'Galileo' or a part of the consensus, is just where you choose to draw a line for the start and end dates. The arbitrary nature of which shows up exactly why these memes are so utterly flawed! Galileo was Galileo and trying to make serious comparisons in support of any take on climate science is just plain bonkers.
  23. Philippe Chantreau at 02:41 AM on 1 October 2011
    Modern scientists, following in Galileo’s footsteps
    Tom makes an excellent point. Someone, maverick or not, may very well be right about a subject and at odd with accepted ideas on that subject. However, it takes more than the correct insight to convince others, it takes sufficient evidence. Science is not a game of "I told you so 20 years ago." If the evidence supports accepted ideas better than new ones, they will remain in place until more evidence is acquired. It is possible that some true skeptics are right about the role of CO2 in climate, but they have so far furnished no evidence near sufficient enough to overturn the current, painstakingly acquired model of Earth climate.
  24. Dikran Marsupial at 02:38 AM on 1 October 2011
    2011 Sea Ice Minimum
    Tom Curtis Thanks for that, being wrong is always an effective way of learning! The models in the Stroeve et al. paper (thanks muon) have a sigmoidal shape, which is strong support for that kind of model.
  25. 2011 Sea Ice Minimum
    No shame for an out of work philosopher to be scooped by Bob Grumbine on Arctic ice.
  26. Stephen Baines at 02:35 AM on 1 October 2011
    Understanding climate denial
    Tristan, I agree that it will be hard to turn any of the big names. Afterall, it is their uniquely active intransigence that has made them "big names" in the first place and which has put them in the position where reversal will lead to public humiliation. If they hadn't sold themselves down the river intellectually, they would have been convinced by the evidence years ago. But for the same reason I think we should be careful not to paint too broad a canvass from their unusual example. That way leads to nihilism. In my experience, many people who "deny" climate change do so on a much more passive/indirect basis. (Note, I do not consider people who post on internet blogs a random sample of these people!) They are either going along with others they relate too, against others they don't relate to, or they are challenged by the idea that the effect of humans could compare to the power of nature. With all the noise surrounding communication about climate science, those indirect associations take over. But I do not believe they are not as committed personally to that position as the public faces of denial. They will listen to evidence when presented by a non-threatening source. In every major environmental debate on which the science spoke clearly, the science has won in the end, despite enormous efforts to derail it. That is not a call to complacency - it took effort. But you have to think that most people can be convinced by the evidence, else we might as well just give up and colonize Mars.
  27. 2011 Sea Ice Minimum
    Tom C: Bob Grumbine scooped you with a logistic curve fit: By my estimation method, there's about a 50% chance (54%) that 2035 or some year before that will show zero ice extent for September. It's only 6% that we'd see zero ice in 2029 (or before). And rises to 96% that we'll see zero ice (for the month) in 2042 or before. The 'or before' is important. Similar shaped graphics from model runs in Stroeve et al 2007, although the earliest ice free point in that paper was 2050.
  28. 2011 Sea Ice Minimum
    Dikran @38, as the sea ice area decreases, its limit comes closer to the pole. Consequently the angle of the incoming sunlight to the horizon decreases, and less energy per square meter is recieved. Hence a lower ice albedo feedback. As the minimum sea ice extent is in September when the sun is already low, that may well be enough to justify a Gompertz model. Not that I would in anyway dispute Larry Hamilton's final sentence.
  29. 2011 Sea Ice Minimum
    TomCurtis. Dang. You just took the wind from my sails. Being an ecologist and all, Gompertz is one of my favourite sigmoids. I was about to plug the data in, and whaddaya know, I refresh and discover that you've pipped me! Pretty cool trajectory though...
  30. Dikran Marsupial at 02:05 AM on 1 October 2011
    2011 Sea Ice Minimum
    Tom Curtis, the Gompertz model, that takes me back a bit! Is there any reason to assume that the ice loss will slow as it reaches zero rather than speed up? I would have thought that it would continue accelerating due to the albedo feedback thing. It would be nice to use a method that handles the fact you can't have a negative extent properly (in the credible/confidence interval as well as in the projection). It might be a nice application for Beta regression (where the Gaussian noise assumption is replaced with a Beta distribution with the lower limit at zero and the upper limit learned from the data (or set to the surface area of the globe). Shame the GPML toolbox doesn't support it (yet).
  31. Understanding climate denial
    Very well, Tristan, I will confess. I was certain of GW by the year 1989. And until 2004 I thought it had to be the sun. In the end I got convinced by the facts I'm pushing forward nowadays like someone who quit smoking attacks everything and all in sight to with tobacco :) What have I gained? Actually some insight into denialism, particularly AGW-denialism. But a look over this thread will give same insight :)
  32. OA not OK part 20: SUMMARY 2/2
    Harking back to Part 4 of the series, it's instructive, if apparently semantic, to note that pH 7 is not actually often the point of "neutrality", in terms of hydronium and OH- equivalence. Further, the pH of "neutrality" is temperature-dependent, and in the 'real world' it can wander half a pH unit or more from 7. As I said, it's largely semantic, but when arguing with acidification deniers it can be quite pertinent...
  33. Dikran Marsupial at 02:00 AM on 1 October 2011
    2011 Sea Ice Minimum
    dana1981 ;o) Do feel free to include the 2010-2012 predictions, the model assumptions are not too unreasonable for short term predictions, but do also include the ones from #34 to show how sensitive projections can be to the assumptions on which they are based, which is a useful lesson.
  34. Modern scientists, following in Galileo’s footsteps
    #34 John Russell -- Your point about mavericks is well taken. I wish we could quantify it somehow. E.g. Even for a short time period estimate the percentage of maverick ideas that are proven right, vs. those that end up in the dust bin. No doubt, it's tiny. However, I'm not sure there's a way to fit that argument fits in this particular rebuttal. The main point is not that the majority is usually right. In fact, climate is an example where some early mavericks were, in fact, proven largely correct. I think it is worth pointing out that mavericks proven right is a rare exception, though it gets complicate to try to shoehorn that into this particular rebuttal. But the larger point is not "are mavericks usually wrong, or right?" but "what is the basis of, and merit to, their position?" What do they bring to the table? Are they bringing fresh data, a new discovery, observation, new or analysis that withstands scrutiny? Or are they just coming with cherry-picked data and rhetorical ploys to try to sway opinion? As Weart stresses, the scientific establishment was correct in rejecting Arrenhius and Callendar, not because they are mavericks, but because their evidence just wasn't strong enough...yet. #37 les There are indeed different views about Galileo's contribution. Certainly his defiant, a bit in-your-face style -- not just his view of Copernicanism -- provoked the Pope, and it the dramatic trial elevated him to mythic status. And you're right that modern science -- increasingly a collaborative, rather than individualistic enterprise -- is far closer to the quiet, methodical style of Kepler et al than the "Hero Scientist" myth. However, few science historians -- even those who adamantly reject the hero myth -- would go so far as to dismiss Galileo as nothing more than a "fine instrument maker with a great imagination for measurement." His proto-scientific methodology, while not wholly unique, was a clear break with the traditional reference to classical texts. Who knows. Perhaps I've succumbed to the "Biographer's Syndrome" of overly identifying with their subjects. But I suspect that Galileo's methodology -- more than his semi-martyrdom -- is what prompted A. Einstein to dub Galileo "the father of modern physics—indeed of modern science altogether," and Stephen Hawking to state, "Galileo, perhaps more than any other single person, was responsible for the birth of modern science."
  35. Climate Change Could be Expensive for Canada
    Jonathan, The report cites this peer-reviewed study, which shows negligible change in winter mortality in 3 Canadian cities assessed. On "reduced energy demand", note that the report also doesn't quantify increased energy demand due to increased use of air conditioning, so it's quite a stretch to classify that shortcoming as one-sided. I haven't read the whole report and can't comment on the other potential benefits you mention. It's always preferrable, in my view, for these sorts of studies to be published in peer-reviewed journals, as that process can tighten them up. Mainstream economic studies (example: U.S. EPA, DoE) tend to not include in assessment of benefits reduced climate change and pollution, and reduced military costs. I wouldn't conclude that economists look "foolish", although I'll note that such studies often get cited as evidence of a net negative economic impact.
  36. Climate Change Could be Expensive for Canada
    Jonathon @2, "Overall, the report focused almost exclusively on the cons, while omitting the pros." You are missing some key points. This report forms part of an ongoing "Climate Prosperity series" series, each report deals with specifc aspects of AGW and how it will likely affect Canada. So the report featured here has to be viewed in context. The report under discussion here was written because: "Little attention had been paid to the costs of inaction on global climate change and what this could mean to Canada economically as greenhouse gas emissions rise and climate change plays out. No nationally-focused economic study existed, until now. We found that climate change has a real and growing price tag to Canada and it could be expensive." Earlier this year NRT produced a report titled "Degrees of Change: Climate Warming and the Stakes for Canada". The purpose of that report was to document, "how Canada will be affected in a climate-changing world. The earth is warming and Canada is already experiencing this change at an even faster rate than other nations. Climate change promises to be both pervasive and pernicious. What will it mean to Canada? How will it impact us? What can we expect?" In that report more focus was placed on the pros and opportunities. The NRT has looked at this very closely and at the end of the day the pros are probably going to outweigh the cons, and adaptation and mitigation will be costly, and doing nothing will cost us even more. One of their primary conclusions is that: "The highest costs result from a refusal to acknowledge these costs and adjust through adaptation."
  37. Eric (skeptic) at 01:51 AM on 1 October 2011
    Are you a genuine skeptic or a climate denier?
    Tom, when you have a chance, please address my paleo argument in that thread My contention is that the quantified sensitivity estimates rest solely on models, there is no other way to convert the large paleo temperature change to the smaller one for the doubling of CO2. I agree with your economic assessment, that it is a huge task. Rather than carbon offset purchases I would favor a tax and rebate like that proposed by Hansen to include a CO2-based tariff on imports. It makes it rather easy to step on the brake lightly to see unpredictable economic impacts and make adjustments. One thing you have left out of your analogy is technological progress that makes it easier to brake. That is being funded and studied currently using biology, technology, genetic engineering, etc. Combined with a long timeline, this will be a viable solution, but obviously that requires essentially the same degree of non-denial that you are looking for.
  38. 2011 Sea Ice Minimum
    Dikran, I can include your 2010 and 2011 predictions from #25 in the soon-to-be published 'lessons' post on Arctic sea ice, if you'd like :-)
  39. 2011 Sea Ice Minimum
    Seeing we're showing pretty pictures, I'ld like to add this one to the photo album: The graph is by Larry Hamilton, who explains it thus:
    "It's just curve-fitting, but with a slight difference. Others tend to use linear, quadratic, exponential or logistic curves. Quadratics actually rise in the early years, then later crash below zero. Logistics have the more plausible property of approaching zero at a slowing rate, but the deceleration and acceleration phases must have the same rate. What this graph shows is a Gompertz curve, still relatively simple but yielding an assymetrical S. It looks similar to a quadratic but the differences are improvements: no rise in the early years, no crash below zero. The Gompertz predicts a slightly lower value than the quadratic for 2011: 4.4 instead of 4.6. It crosses the 1.0 line a few years sooner, but after that approaches 0 asymptotically. NOT that such curve fitting is more than a what-if exercise!"
    Graph and quote from Neven's blog. With the gompertz model, it should be noted that once the average sea ice extent falls below about 0.5 million km^2, the Arctic will be ice free on some summers (but not all) due to variations in weather, so on this estimate the first zero ice minimum should be around 2030 even though there will be minimums with above zero ice for several years, even a few decades later.
  40. Understanding climate denial
    Given this, It's going to be pretty hard to 'turn' any of the big names in the CAGW rejecting community. Just think how hard it'd be for them to 'turn' you! You might argue that logic/science is on your side (note: that's what they think too) so it's not a fair comparison but that's actually almost irrelevant. Cognitive dissonance alone isn't weighty enough to counteract all the other forces at play.
  41. Are you a genuine skeptic or a climate denier?
    Eric (skeptic) @486, the estimate of climate sensitivity is largely independent of the estimate of its individual components. This is partly because, in models, uncertainties tend to be coupled, so that if one factor is not as positive a feedback as expected, some other related factor will not be as strong a negative feedback so that the net effect on climate sensitivity is small. This is the case, for example, with the water vapour/lapse rate feed back. It is also partly because for factors where the uncertainties are independent, the final values will likely show not bias. So, for example, evidence is currently showing the ice/snow albedo feedback to be much more positive than is found in models. I do not conclude from that that climate sensitivity will be higher than expected because, odds are that some other factor (or group of factors) will show a lower sensitivity. Perhaps that factor will be climate sensitivity. We can hope that the coupled Global Circulation Models are all biased in favour of high climate sensitivities, but assuming that they are is neither scientific nor skeptical. Consequently resting your expectation of low climate sensitivity on just one factor is selective reasoning. More importantly, climate sensitivity is not just estimated from models. Estimates of climate sensitivity from paleo data, by definition, do not underestimate or overestimate any feedback. As paleo data consistently suggests climate sensitivities around 3 degrees per doubling of CO2, it is a very reasonable assumption that particular errors in estimating particular factors in coupled GCMs will cancel out. Given that, although you may think the evidence favours a low climate sensitivity, acting as though there is not a high probability that you are wrong is foolish. Turning to the other side of the equation, assuming 2.5 < the climate sensitivity < 3.5, the US and Australia need to eliminate all CO2 emissions by 2020, either by direct reduction or by purchase of overseas carbon credits, if we are to not face massive ecosystem failures. If the climate sensitivity is greater than 3.5 degrees C per doubling, those eco-system failures are probably already locked in. As a simple fact of economics, decarbonizing the economy in 20 years is a huge economic task. Doing so in 10 years or less will destroy the economy. So, suppose we act on your assumption that climate sensitivity is between 1.5 and 2.5 degrees per doubling of CO2, but that in 10 years we find out the IPCC central estimate was more accurate. By not acting now we have committed ourselves to destroying the economy by decarbonizing, of of having it destroyed by massive ecosystem collapse within a generation or so. In contrast, suppose we act on the supposition that the IPCC is correct, but in 10 years we find out that you were correct. Well, then we are ahead of the game, and can slacken of the effort. We have lost very little in the process. We are like drivers setting ourselves up for a turn. We know we have to turn sometime. By breaking later, if we make the turn, we will gain an advantage in terms of economic growth (which is not to be sneezed at). But by breaking later we significantly increase the risk of not making the corner. As it happens, our navigator is telling us "Brake, brake, brake" and has his fingers firmly grasping the dashboard with white knuckles. In the meantime we are pushing a little harder on the throttle and saying, "Not yet!" Of course, economies and ecosystems do not steer like rally cars. Rather, they steer like super tankers. You can see why I don't want your putative congressman at the wheel. Like most elected politicians, s/he's all about the short term electoral cycle, with no thought to the long term consequences.
  42. Understanding climate denial
    People become attached to their opinions. Opinions represent who we are, and accepting that an opinion of ours is wrong comes at a substantial personal cost. The cost rises when your opinion is also the basis for your job/hobby/friendship circle/fame. People can go to amazing lengths to retain their opinions. A bit of cognitive dissonance is easy enough to maintain. Consider Monckton's plight. If he changes his mind about AGW he has to face two nasty thoughts. A) He isn't as clever as he thought he was and needs to do some serious grovelling and B) He aided and abetted a system that imperils the life and prosperity of the planet. If anyone wants a shining historical example take a look at Millerism.
  43. Climate Change Could be Expensive for Canada
    Jonathon, Increased wintertime temperatures may lead to more deaths rather than less. You have to recognize two things, first that warmer temperatures will result in greater extreme precipitation events in Canada and greater variance; and secondly (most importantly) a lot of Canadians travel on ice in the North. I've already first hand seen (I'm from Northern Canada and of Inuit descent) the increase in people going through the ice on skidoo and getting into dangerous situations because of dangerous ice conditions due to increase wintertime warmth. We are far better suited up here to deal with cold than we are with heat.
  44. Climate Change Could be Expensive for Canada
    Jonathon: With regards to: Likewise, the increased deaths due to warmer summertime temperatures were included, but not the decreased deaths due to warmer wintertime temperatures. In a country where cold is a bigger issue than warmth, I would think this would be rather relevant. I would not be too sure of this. While one would have to go to Statistics Canada or a similar source to get a full picture, I have found these links to some major cold- and heat-related weather events on Environment Canada's website. The events at the bottom of the pages are, I am led to understand, the biggest in the database. There is a single heat wave event (to be fair, in the midst of the Depression) with 1,186 recorded fatalities; a number two orders of magnitude greater than that of any of the cold snap events with fatalities themselves. Perhaps I shall look into this more on the weekend. At any rate, even if Canada were to find that, at the national level, the benefits of global warming outweighed the costs, these benefits would not be evenly distributed regionally within Canada, and of course they would pale in comparison to the costs of low-lying, sub-tropical and tropical regions (e.g. Louisiana, Texas, Florida, the Netherlands, Bangladesh, &c, &c).
  45. Understanding climate denial
    #128, Well yes Albatros, I sometimes do prefer 'graphic' for clarity - then quite often have a good laugh at the response or total lack of it... I wonder how any taboo could be illustrated by non-graphic examples of it. Anyway, the argument made there is rather subtle, or let's say 'philosophical'; I think the message was clear at least for those interested. 'Facts are taboo' describes a typical denier's reaction to facts. Reactions like: flying into a rage, or running away, or censoring - the works.
  46. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman: "Two other meteorologists do not share Jeff Masters Expert Opinion. One is Anthony Watts and the other Joe Bastardi. Both of them are meteorologists that have been in the field for many years. They would see similar data that Jeff Masters is exposed to. Why don't they see this same extreme year?" You've asked the right question, Norman, but for the wrong reason.
  47. Dikran Marsupial at 00:55 AM on 1 October 2011
    2011 Sea Ice Minimum
    This is what you get if you use a quadratic covariance function, giving a Bayesian alternative to Tamino's model (well closeish anyway) This gives rather poor predictions for the last two years: prediction for 2010 = 5.414904 (+/- 1.124377) prediction for 2011 = 5.338500 (+/- 1.130803) prediction for 2012 = 5.262056 (+/- 1.137584) However Tamino's model had more data to work with, so it is possible that with more data the model will decide that there is more curvature and less noise in the data than at present. I still think Tamino's method is better; I suspect the problem here is that the model has a couple of hyper-parameters that have been optimised, whereas a proper Bayesian would integrate them out. It may be there are two ways of explain it the data, high curvature/low noise and low curvature/high noise and the optimisation approach only finds the latter, whereas the simpler frequentist approach finds the former. Self-skepticism is vital in statistical analysis, which is why I greatly prefer a physical model over a purely statistical one.
  48. Understanding climate denial
    cRR@126, Actually, I did understand, they were good examples, the content though was not really consistent with that we prefer to use here at SkS..that is all. You are welcome to try again using less graphic terms.
  49. Dikran Marsupial at 00:45 AM on 1 October 2011
    2011 Sea Ice Minimum
    Tom Curtis yes, the further away you extrapolate the less reliable the projection gets, just on statistical grounds, whether you use Tamino's method or mine. If you look at the credible interval for the ice free Arctic, the model is basically saying it doesn't really have any idea of how soon it will happen, other than it is unlikely to be before 2027 (the upper limit is effectively at infinity). I don't mind saying what the model says about when the Arctic will be ice free in Summer, but I wouldn't make a serious prediction about it.
  50. 2011 Sea Ice Minimum
    Dikran @29, you may prefer Tamino's quadratic model, but he specifically disavows trusting its indicated trend except in the short term and, last time I looked, refuses to make a prediction about how soon until a zero ice minimum in the Arctic.

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