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Comments 68351 to 68400:

68351. angliss at 09:16 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Sphaerica (#14) - Odd, I thought I had specifically suggested to Jim that he add Douglass et al 2008 and got no response. I'm not trying to imply that Jim did anything on purpose, but rather point out that he may have accidentally filtered out papers like Douglass et al 2008 because of the way he designed his search parameters. FWIW, I'm not using "bias" in the colloquial sense here - I'm using it as I would in my day job as an EE: bias is a detectable and correctable error independent from random processes like noise. I apologize for not making that clearer in my initial post. Chris (#15) - I have read the paper, although admittedly not recently. On a quick skim of it, however, I found this in the summary: (The use of tropical tropospheric temperature trends as a metric for this test is important, as this region represents the CEL and provides a clear signature of the trajectory of the climate system under enhanced greenhouse forcing.) On the whole, the evidence indicates that model trends in the troposphere are very likely inconsistent with observations that indicate that, since 1979, there is no significant long-term amplification factor relative to the surface. If these results continue to be supported, then future projections of temperature change, as depicted in the present suite of climate models, are likely too high. Also: The last 25 years constitute a period of more complete and accurate observations and more realistic modelling efforts. Yet the models are seen to disagree with the observations. We suggest, therefore, that projections of future climate based on these models be viewed with much caution. IMO, this meets Jim's criteria as described in his first post. Regardless, I am sorry for not suggesting this paper's inclusion it back on Post 1, as doing so might have avoided any unpleasantness.
68352. Dave123 at 09:14 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Richard...what **global** warming spike at 1100 AD? I'm only aware of regional high temperatures smeared out over a couple of hundred years. For that matter, all the hockey sticks I'm seeing for **global** temperatures don't show anything at 3000 BC either. ps... I'm sure not going to be around in 2100. Nor are my children likely to be. If I had grandchildren right now, it wouldn't be a good bet either. How do you plan to be around in 2100?
68353. ahaynes at 09:13 AM on 15 December 2011
       Infrared Iris Never Bloomed
       FYI Dana, Lindzen begs to differ with your assessment, and has a powerpoint presentation with counterarguments for at least the early-2000s papers. The argument-counterargument volleys are over my head, at least as much of same as I want to devote to this. So, 2 Qs - First, what heuristic does the non-expert use in a situation like this? I think the answer is to ask: do unrelated scientists looking into your hypothesis think that the evidence from their research supports it? (If I'm the scientific bystander, and the hypothesis-holding scientist stands his ground, is there any other way I can go about forming an informed view?) And second, not using a heuristic, could someone please (of the expert ilk) address some of Lindzen's counterarguments, e.g. that Lin et al 2002 were "ignoring the fact that we were taking Ac(260) as a surrogate for all tropical upper cirrus, and instead asserting that the clouds defined by Ac(260) were essentially the only clouds we were considering.")
68354. Dave123 at 09:09 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       @16. So what you're saying Richard is that you can't take initial boundary conditions in say 1970, run a suite of models through 2010 that show good correspondence to the real temperature trends and use the climate sensitivity coming out of that? That you can't use paleoclimate data to calculate prior climate sensitivity and apply those estimates to present conditions? What is "knowing" to you anyhow? You've got an unstated premise/bias in there that needs to be laid out. Do words like 95% confidence mean anything to you? Are there other areas of knowledge where calculations are done that you also require waiting for? I keep thinking of the mention of a mole on your skin in another post. The individual variability of cancer progression is large...so why should you trust the past clinical data and progression models?
68355. chris at 09:07 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       We've got lots of actual observations Richard (#16). For example, the earth has warmed by around 0.8-0.9 oC since the middle of the 19th century, while [CO2] has risen from around 286 ppm then to 389 ppm now. A climate sensitivity of 2 oC should then give an equilibrium warming of: ln(389/286)*2/ln(2) = 0.87 oC We know that we haven’t had the full warming from this enhancement of greenhouse gases, since it takes the earth many decades to come to equilibrium with the current forcing resulting from raised greenhouse gases. Likewise we know that a significant part of the warming from this enhancement of greenhouse gas levels has been offset by manmade atmospheric aerosols. On the other hand some of the warming is due to non-CO2 sources (man-made methane, nitrous oxides, tropospheric ozone, black carbon). Non greenhouse gas contributions to this warming (solar, volcanic) are known to be small. Overall, it’s rather unlikely, given the warming since the mid-19th century, that climate sensitivity is less than 2 oC. This is expanded on in more detail in Knutti and Hegerl, in Murphy et al. (2009), in Rind and Lean, 2008, in Hansen et al (2005), etc. etc. So the evidence simply doesn't support a climate sensitivity that is below 2 oC. The evidence in fact supports a climate sensitivity of around 3 oC at maximum (evidence-based) likelihood. It's silly to make arguments based on the premise of ignorance! In science we assess hypotheses on the basis of the evidence.
68356. Richard Arrett at 09:06 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Dave123 @17: I guess we will have to agree to disagree on who has the burden of proof. Personally, I plan on measuring the average global temperature at 2100, and the sea level rise at 2100. Then we will have actual observations which we can use to determine the climate sensitivity. If CS turns out to be 1.3C - that will imply there is no indirect amplification feedback. If CS turns out to be 3C or higher - you are right. If CS turns out to be 2C or lower - skeptics are right.
68357. Richard Arrett at 09:01 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       scaddenp #10: You have the burden of proof wrong. I don't have to provide an alternative to natural variability because that is the null hypothesis. What caused the warming spike around 1100 AD? What caused the warming spike around 3000 BC? The CO2 data (ice cores) tells us it couldn't have been caused by CO2 - because CO2 was constant at around 280 ppm for during both of those temperature spikes. That is why the null hypothesis is natural variability. That is why you have the burden of showing that the warming spike we are currently in is due to CO2 and not the other causes (whatever caused the warming in 1100 AD or 3000 BC).
68358. skept.fr at 09:00 AM on 15 December 2011
       (Fahrenheit) 451 ppm
       #81 KR : OK, my apologies for the misinterpretation of your sentence : "And yet - you seem to repeatedly call for "go slow" approaches, to minimize economic shifts or disruption, to 'tone down' the urgency. This despite the (acknowledged) lead time required to shift energy production from fossil fuels." It sounds to me as if I was supposed to leave or silence all my doubts because of a urgency to act. But it was not your thought, so sorry. "given the observed intransigence of the fossil fuel industry and conservative politicians" No. Like the Sphaerica's "magnats", this is a typical misinterpretation of reality. Look at Peters et al 2011 article I already quoted, nearly all the increase of CO2 emissions since 1990 come from non-OECD countries who're escaping poverty. And so for the projected decades, as IEA WEO 2011 put it : "The dynamics of energy markets are increasingly determined by countries outside the OECD. Non-OECD countries account for 90% of population growth, 70% of the increase in economic output and 90% of energy demand growth over the period from 2010 to 2035." So even if the last 15 years US blockage to climate decision is a pity, partly due to lobbies, you should IMO leave this Western-centric view of the energy-climate problem for the future, because even US is henceforth a small part of this problem. (At least, carbon intensity of US economy made small progress, this is not at all the case when a poor country begins its development.) In real choices for developing countries, the problem is not the fossil fuel industry (not speaking of Western conservatives), it is the incapacity of wind and solar industries in their current technologies to provide the regular, large and if possible cheap basis for an energy infrastructure needed at a national scale. And also to provide fuel for transportation, of course. BRICs and other developing countries are not foolish, if non-fossil solutions were the most interesting for their energy mix, their would have chosen this way for a long time: no pollution, no dependency of foreign providers, no climate warming... # 82 Sphaerica : the French expression for your repeated claim is "procès d'intention", I don't know the English counterpart. I'm tired too. But I think I have now a clearer idea of how skeptic is "Skeptical" Science. Readers will appreciate how clearly my different points and concerns have been answered here.
68359. Dave123 at 08:58 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       @12- "It has been" warmer/cooler "in the past when CO2 was 280 ppm". A. There is no such thing as "natural variability" in the sense that things move around with no recourse to a physical explanation....which is what I hear whenever someone on the "skeptic" side uses that phrase...unless they mean "it's too complicated for me to figure out, so you can't understand it either". B. Your statement is pointless unless you also hold all other variables constant... insolation, albedo etc. And you need to be clear on whether this is a stable or transient condition. Do you have that information? C. And for SkS you really ought to cite the dates, and the papers providing the temperature and CO2 information and other control information. Anything else just isn't up to standard. D. I submit that this data has been developed, presented in peer reviewed papers, and summarized and presented here on SkS. That in sum your statement that it has been warmer and or colder at 280 ppm, and implying that all other things are equal is in fact false because it has been shown all other things aren't equal. E. And if you have been immersed in this discussion through sites providing direct access to peer-reviewed literature...such as SkS and RealClimate you'd have to say that given the data on the table, for a skeptic to make a case they must refute it. The ball is in their court, the burden of proof is on them.
68360. Richard Arrett at 08:55 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Sphaerica, #8: We don't actually know that. We know from physics that we should experience around 1.2C by 2100 from the direct effects of CO2 warming. However, what is in question is the amount of indirect feedback. There are lots of theories and projections - but no actual observations. So until we can actually measure temperature and/or sea level when 2100 rolls around, we don't actually know what the climate sensitivity number will be. It may be 3C or it may be 1C - we just don't know.
68361. Bob Lacatena at 08:53 AM on 15 December 2011
       Galactic cosmic rays: Backing the wrong horse
       106, Eric, Except GCR can't be added to the model physics because no one has demonstrated a working mechanism and defined the underlying physics needed to incorporate it into a model. By contrast we know the exact bands at which CO₂ absorbs radiation, the emission times, the density throughout the atmosphere, the overlap with other gases, the resulting TOA emissions spectrum, the energy associated with each photon, and 80 bazillion other details that allow us to directly model the physics. For GCRs we have "hey, look, there was maybe sort of a correlation over a several million year time scale, given a window of tens of millions of years, give or take, and a questionable proxy for the strength of GCRs, and no correlation whatsoever in recent, hard, direct instrumental measurements." GCRs are a non-starter until someone does a lot more work and gets some positive results from it, and I don't expect that to happen for a decade at least, if ever. Including GCRs now might as well be accompanied by the well-considered effects of Eurasian Leprechaun Farts (ELFs, a well-known Christmas time seasonal impact).
68362. chris at 08:50 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       angliss (#9), that's simply incorrect. Nowhere in Douglass et al (2008) is it suggested "that the climate isn't warming because the analysis erroneously concludes that there's no evidence for tropical tropospheric warming". It's very easy to establish that fact - one simply has to read the paper! You seem to be arguing on the basis of an easily-established false premise. Douglass et al are very clear that they are addressing something rather specific. Santer et al (2005) determined that apparent differences in modeled and measured temperatures in the altitude-dependence of temperature trends in the tropical zone during the satellite era is not an indication that there is fundamental discrepency between models and measurements since the uncertainty in the latter overlaps with the variance in the models. Douglass et al's reanalysis purported to show that the uncertainties are actually sufficiently small that a strong statement about fundamental discrepencies in models and measurements in this subset of tropsopheric data can be made. Of course Douglass et al's analysis was pathetically flawed. But that's not the point. In the context of this thread, Douglass et al's analysis has nothing to say about whether the climate is warming or not, nor the origins of warming. In fact Douglass et al state completely explicitly that the climate is warming (see their Table 1) since they accept the very marked surface warming trends that are well established.
68363. Bob Lacatena at 08:43 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       angliss, Roger Gram, Do you think it might have been possible to simply post a comment saying "Hey, you missed one, what about the Douglass 2007 paper?" rather than: (a) Implying that Jim didn't try hard enough

       "If you want to list all the skeptic's papers, you need to look more carefully. "

       or (b) Implying that his entire method of locating papers was perhaps biased towards getting some sort of desired result

       "questions that need to be asked about why, and whether the methodology might be inadvertently biasing the results of the study"

       Hint: I'm sure Jim would gladly add this paper, and any others you find, to the list. I'd further point out that in part 1, Jim explicitly gave reasons for not including Klotzbach et al. (2009), which appears in many ways to be similar to the Douglas paper. Once again, maybe a simple question along the lines of "did you consider this?" would have served better than veiled (whether purposeful or not) implications of impropriety and deceit? Consider Jim's comment here, on part 1, which ends with the statement:

       I welcome suggestions for papers I missed, as Troy has done.

68364. Eric (skeptic) at 08:43 AM on 15 December 2011
       Galactic cosmic rays: Backing the wrong horse
       Either the GCR needs to be added to model physics or it will have to be ignored. Very short term empirical analysis, although still requiring a model, should not need GCR included as we see from the Laken and other papers. For solar cycle sensitivity-based estimates, I don't see how GCR can be ignored if it has any role at all. For longer term empirical it probably needs to be in the model.
68365. Richard Arrett at 08:39 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       #6 Utahn: The part which requires that skeptics have the burden of disproving AGW.
68366. Richard Arrett at 08:38 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       #4 John Russell Again - this all depends on who has the burden of proof. It has been warmer in the past than it is currently, and CO2 was at around 280 ppm. It has been colder in the past than it is currently, and CO2 was at around 280 ppm. So, given that natural variability is the null hypothesis, don't you have the burden of showing why the current warming is due to CO2 and not to whatever caused prior warming spikes (while CO2 was at 280 ppm)? But to take a stab at answering your question, perhaps aerosols are an opposing forcing which are counteracting CO2.
68367. Bob Lacatena at 08:31 AM on 15 December 2011
       (Fahrenheit) 451 ppm
       80, skept.fr, I am now officially beginning to tire of the latest denial tactic, which is to purport to have this huge interest in the welfare of the poor in third world countries, and that the only humanitarian way out for them is through more and more and more use of fossil fuels. You complain that my "fire age" metaphor is a scare tactic, and then calmly resort to the same by over and over implying that anything less than wanton, remorseless use of fossil fuels to lift the third world countries from the sludge would be a crime against humanity. Then you say there are lots of uncertainties in the science. Then you imply that fear-mongering is the business of certain climate scientists. Your words (and anyone here is free to go back and review them) call for delay, delay, delay for any reason you can think of — we're not sure, they're fear-mongering, it will hurt the poor. You seemingly want to mollify your conscience by saying you are in favor of pricing carbon externalities, and yet 99% of your words instead say "do nothing." I think you need to stop pontificating, state clear priorities and goals, and then start generating comments that are actually in line with those goals, rather than generating whatever stream of comments will help you arrive at the same, tired conclusion that "we really should wait on this whole get-off-of-fossil-fuels thing."
68368. KR at 08:17 AM on 15 December 2011
       (Fahrenheit) 451 ppm
       skept.fr - "From an ethical stance, I can no more accept a 'end justify the means' approach, which is implicit in many critics of my position including yours." I would have to disagree most strongly with your interpretation, skept.fr. I do not believe I have ever stated anything of the sort, and consider that an unjustified Strawman distortion. My position is that climate change has significant, negative impacts, that addressing emissions will not cost too much, and will in fact actually save money over the mid to long term. And from that, that any delay in addressing CO2 emissions and climate change increases the cost of dealing with it. That doesn't by any means justify making stuff up, or running around like Chicken Little. But it certainly means being very clear what the range of likely climate impacts and costs are when discussing the matter. I would agree that drawing lines in the sand, lines that (given the observed intransigence of the fossil fuel industry and conservative politicians) are likely to be crossed - that is perhaps not terribly productive. But neither is soft-pedaling the cost of not acting, which appears to be what you would prefer (here, here, here, for example).
68369. Roger Gram at 08:12 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       7 Sphaerica, You seem to think that I'm defending the Douglass-Christy-Singer paper. But I'm not. Rather, I'm puzzled that a paper that claims to show that the models are wrong (and was trumpeted and celebrated in right wing and denialosphere sites) would not be included in a database of skeptical peer-reviewed papers. Your characterizing this paper as highlighting "one narrow area of inconsistency in the models" was clearly not shared by mainstream climate scientists. The reaction at the time by Ben Santer and RealClimate was one of surprise and alarm that such a paper could pass peer review and be published. There followed an intense effort to quickly rebut this paper, both on-line, and in the scientific literature. I applaud the work of Skeptical Science, and the effort to develop this database. However, I think the database is quite incomplete.
68370. skept.fr at 07:58 AM on 15 December 2011
       (Fahrenheit) 451 ppm
       #78 KR : I write here on a web site called Skeptical Science. As Stephen Schneider once nicely put it in his famous reflexion about the 'double ethical bind', "as scientists we are ethically bound to the scientific method, in effect promising to tell the truth, the whole truth, and nothing but — which means that we must include all the doubts, the caveats, the ifs, ands, and buts." (my underscore) So either SkS is bound to this scientific ethic, and for the long list of climate effect you mention (or Sphaerica in his text), it must also be precised the doubts, caveats, ifs, ands, buts. Or SkS is bound to a layman / militant ethic, and then it is ruled by the second part of Schneider quote : "On the other hand, we are not just scientists but human beings as well. And like most people we'd like to see the world a better place, which in this context translates into our working to reduce the risk of potentially disastrous climatic change. To do that we need to get some broadbased support, to capture the public's imagination. That, of course, entails getting loads of media coverage. So we have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of any doubts we might have." (my underscore). I already gave some precise examples for the Sphaerica 451 ppm world, notably the Fire Age metaphor that is not supported by vegetation-AOCM coupled model on a global scale and is misleading as such, without precision that the "fire" in question concerns some regions (and usually not at 451 ppm concentration in literature, rather a doubling CO2 a minima for model projections ; if I recall correctly 451 ppm is even under the SRES B1 concentration in 2100, and best estimate of the transient sensitivity for such forcing is quite low). And there are others. If you read carefully climate literature, you perfectly know that there is still divergence among AOGCMs on the amplitude and frequency of changes related to precipitation and temperature, and it is even more true for regional projections. Climate science is not just made of Hansen or Rahmstorf papers (whatever their quality), that's why IPCC exists. So, if you speak of droughts, you must recall that IPCC SREX 2011 just give of "medium confidence" for their increase ; if you speak of crops productivity, you must recall that IPCC AR4 WG2 suggest it will continue to increase with a 1-2K warming on low latitude and a 1-3K warming in high latitude, and that, with medium confidence, 'the marginal increase in the number of people at risk of hunger due to climate change must be viewed within the overall large reductions due to socio-economic development' (chapter 5). And so on. These are the 'buts', 'ifs', 'ands' of Schneider's scientific ethic. From an ethical stance, I can no more accept a 'end justify the means' approach, which is implicit in many critics of my position including yours. From a pragmatic stance, I observe the 'doom and gloom communication' strategy is a failure, either for changing personal / societal behaviors or to engage a world policy at successive COPs. These are two sufficient reasons to explain my point. Maybe some here are very happy to reiterate each year the game of COP hope-followed-by-delusion, I'm not. Maybe some here are happy with eternal complaining about 'human-selfishness-that-ignore-the-bad-consequence-of-his-action', without any perceptible effect on the selfishness in question, I'm not. I added a third point : human welfare is my ultimate concern, I don't think a climate-centered assessment of risk on this welfare is fair as we all know that climate mitigation is causally bound to fossil energy limitation. 'Euphemisms' (muoncounter) are everywhere in this debate: in current technology (no CCS available), the only method for not exceeding 450 ppm is to fix now a maximal quantity of fossil for each country and to forbid its use beyond this limit, including many non-OECD countries. Do you want that, yes or not? If yes, I tend to think that you defend a dangerous target for humanity, at least I wait a strong justification that adverse effects of a constrained energy shortage will not be more harmful that adverse effects of the avoided level of climate change. If not, you're probably somewhere in my zone of interrogation: what are the better solutions to promote now (and not in 2020, 2030, etc.)? As I already suggested, my fear is that the 2K/450 ppm target is a Pyrrhic victory for those who are interested in climate mitigation. I foresee a stagnation of climate diplomacy which ultimately profits to the "business as usual" scenario. Sphaerica insistance on the 451 ppm world seems to me a caution to this very likely failure. Maybe I'm totally wrong, maybe 194 countries will adopt without problem the post-Kyoto treaty in 2015, maybe energy transition will be easy and no country will abandon the treaty as some did for Kyoto.... In one sense, I hope so, but I've no rational argument to justify such a hope.
68371. Bob Lacatena at 07:56 AM on 15 December 2011
       (Fahrenheit) 451 ppm
       75, Arkadiusz Semczyszak,

       Many lines of evidence show that the variations in the CO2 growth rate are mainly caused by terrestrial effects...

       Citation please. Otherwise this is mere assertion. Even with a citation... where do you propose all of the CO₂ can be coming from, year after year, from "Nature." Your premise here is laughable. The CO₂ "budget" is closed, and we know we are the cause and what the rate of incline is. To suggest that we don't know when we'll reach 451 ppm is downright laughable. Your supplied citation, on the otherhand, contradicts your own statements. The paper studies uncertainties in the continued uptake of CO₂ by ecosystems, and the probability (as I stated in my post) that this uptake may reverse and instead release CO₂. The opening line:

       Recent evidence suggests that, on a global scale, terrestrial ecosystems will provide a positive feedback in a warming world, albeit of uncertain magnitude.

       From the conclusion:

       Overall, it is likely that, at least on a global scale, terrestrial ecosystems will provide a positive, amplifying feedback in a warming world, albeit of uncertain magnitude.

       Your comments on methane are a non sequitur. As I already stated clearly in my post, there are obviously known differences between a glacial termination and our current situation. No one, anywhere, ever said that the methane feedbacks that we expect are in any way comparable to what was experienced in the last glacial termination, so the fact that the mechanisms are different makes no difference whatsoever. Really, Arkadiusz, you can do a better job of expressing complete and total denial than this.
68372. scaddenp at 07:52 AM on 15 December 2011
       Galactic cosmic rays: Backing the wrong horse
       And as an observation, you seem to still engaged in trying to find evidence for low sensitivity which you appeared to decided is likely a priori rather than from evidence in front you.
68373. scaddenp at 07:51 AM on 15 December 2011
       Galactic cosmic rays: Backing the wrong horse
       You can get sensitivity directly from model, or you can get sensitivity from empirical methods from past climate events. In the former, its pretty hard to see how you could change sensitivity because you have to have physics to add GCR into climate. Lacking evidence or proven mechanism, then that is pretty hard. For empirical methods, then effectively GCR is already included because there is no way to sort out different factors in such studies without a model.
68374. scaddenp at 07:45 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Richard - AGW is not so much an "hypothesis" but a result from our current theory of climate. It could be wrong but you have to explain what is wrong with known physics first. (For instance, why does measured increased radiation from the atmosphere not cause warming). Climate sensitivity is know with considerable certainty to lie between 2 and 5, with a most likely value around 3. Even low end is cause for concern. No scientific theory is even "known to be correct". That doesnt stop us using incomplete theories like gravity for sending rockets to mars. Before you can claim natural variability is responsible you need a credible theory for some natural variability. None has been found. By contrast, normal climate physics has no trouble explaining current observation. So, as far as policy is concerned, would you bet on what is well established in science? or the hope that some magic source of variability will be found to let us off the hook? Which do you think is prudent practise? Would let a strange mole continue to grow because your Dr is uncertain whether it is cancerous or not?
68375. angliss at 07:43 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Sphaerica, #7: Part of Roger's point is that Jim's database doesn't include a bunch of papers by "skeptics," including that one. That Douglass paper clearly suggests that the climate isn't warming because the analysis erroneously concludes that there's no evidence for tropical tropospheric warming, so why wasn't it included in the analysis? It's a fair question, and one I have as well, even though I tend to agree with the analysis' conclusions. If Jim's methodology failed to catch this paper, then there's some fair questions that need to be asked about why, and whether the methodology might be inadvertently biasing the results of the study.
68376. Bob Lacatena at 07:39 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       3, Richard Arrett, We know definitively that climate is not changing due to natural variability. We have narrowed climate sensitivity down to a small enough range, with enough redundant confirmation, that we are fairly confident in what it is going to mean going forward. At this point, the strength of the science is so overwhelmingly strong that the burden does fall on the "skeptics" (a laughable moniker) to provide some evidence that somehow, somewhere, there is something solidly wrong with current theory. This entire series of posts shows that despite how desperately some people would like to do that, how many of them there are, how well funded they are, and how much time they have put into the effort, none of them have come remotely close to even denting the mainstream science, let alone damaging it. Doesn't that tell you something?
68377. Bob Lacatena at 07:34 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       1, Roger Gram, How does the paper you supplied in any way affect the content of this post? Which bullet point in part 2 does it contradict? In particular, however, this particular paper attempt to make a case (one not broadly accepted) for one narrow area of inconsistency in the models, but then leaps to the grand conclusion that because of this supposed inconsistency, the models are entirely suspect and therefore the entire theory of AGW is suspect. You can't see the fallacy in this?
68378. scaddenp at 07:28 AM on 15 December 2011
       Newcomers, Start Here
       imthedragn. If you really want to go into all the gory detail, then can I suggest you work through CO2 series at Science of Doom. You will find all that detail in that extended series.
68379. scaddenp at 07:24 AM on 15 December 2011
       We're heading into an ice age
       'good chance that the arctic melting will stop the Atlantic conveyer by dumpling lots of fresh (therefore lighter) water into the North Atlantic.' I dont believe there is any science supporting this, but please feel free to cite some. There is a postulate (and evidence) that the massive dump of fresh water from ice sheet melting caused a slow down and thus the YD event. However, this was an extremely rapid dump of a lot of water. Summer melt of seaice over many years is in a different order. Even if the Milankovich cycles were strong enough to cause another glacial with CO2 levels this high, the onset is extremely slow - 2 orders of magnitude less than current rate of change. It not a question of whether we would prefer warm or cold - its the rate of change that is dangerous.
68380. Eric (skeptic) at 07:18 AM on 15 December 2011
       Galactic cosmic rays: Backing the wrong horse
       scaddenp, GCR was always a dead issue to me for explaining current warming. Now it is less clear to me over the long run also. I am however still interested in GCR due to its potential modulation of water vapor feedback. What I would like to see is a study examining uncertainties in climate sensitivity due to uncertainties in GCR.
68381. Utahn at 07:09 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Richard Arrett: "Therefore, your conclusion is premature (in my opinion)." Which part of the stated conclusion do you find premature?
68382. DrYew at 07:06 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Hi - It would be useful to get the following simple numbers: 59 skeptic papers are listed... since when? And 59 of how many climate change papers (ie, what was the pool of candidates?) How many authors are uniquely identified in the 59 papers? How many authors are uniquely identified in the pool of candidates? This data would give some sense of consensus DrYew
68383. Eric (skeptic) at 07:05 AM on 15 December 2011
       Galactic cosmic rays: Backing the wrong horse
       Lucky for me, Dr. Laken took part of his evening to explain the TSI-GCR link. Over the long run an active sun means more TSI and an active sun means less GCR (due to more solar wind). The measurements of solar activity are smoothed and somewhat qualitative sunspot counts and TSI and GCR are running averages or proxies. Everything works the way I thought. But on a timescale of days the TSI relationship to GCR is complex due to positioning of the sunspots and other features and the movement of those features. So TSI and GCR (and solar UV) have more complex relationships including time delays. The wording in the abstract refers to those short term relationships (because that is what the paper is about).
68384. John Russell at 07:03 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       @Richard Arrett #3 "This warming which has occurred from 1850 to the present, could still just be a coincidence..." Could it? I think then you need to explain how the a massive increase in CO2 hasn't caused the planet to warm. You're denying the accepted physics of the greenhouse effect -- so you need to provide a convincing alternative explanation.
68385. John Hartz at 06:50 AM on 15 December 2011
       2nd law of thermodynamics contradicts greenhouse theory
       KR: Having followed the multiple, lengthy exchanges between TOP and you and other SkS authors, I am firmly convinced that TOP's sole purpose is to litter this comment thread with excerpts from the G&T paper. In my opinion, this behavior ought to be against SkS Comment Policy. If it were my call, I would ban TOP from posting on SkS and delete all of his comments.
68386. Richard Arrett at 06:48 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Doesn't your conclusion depend on which side has the burden of proof? I thought that AGW was a hypothesis. I thought that the data was consistent with the hypothesis. However, I also thought that the data was also consistent with other hypotheses, and that we did not have enough data to rule out one or the other yet. We don't even know with any certainty yet was the climate sensitivity number is. Therefore, I thought that we did not yet have enough data to definitely say that AGW was correct. So your conclusion is only correct if skeptics have the burden of disproving the AGW hypothesis. My understanding is that skeptics do not bear the burden of proof. I thought the null hypothesis was natural variability, not AGW. The scientists who advocate human-caused global warming bear the burden of proof (I think). This warming which has occurred from 1850 to the present, could still just be a coincidence and correlated with the increased CO2 emissions, but not necessarily caused by them. Therefore, your conclusion is premature (in my opinion).
       Response:

       [dana1981] Incorrect.  AGW is a robust scientific theory which has withstood decades of scientific scrutiny, not a hypothesis.

68387. adesbarats at 06:41 AM on 15 December 2011
       CO2 was higher in the past
       CBDunkerson - thanks for your input. Makes good sense. Rob Honeycutt - thanks for the article link!
68388. actually thoughtful at 06:35 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       Your third bullet is much to weak. Skeptics MUST both explain the observed warming AND explain why CO2 from human caused emissions is NOT causing the warming - as science says it must, overwhelmingly. Not only has no skeptic satisfied your weak bullet point, but none have touched either half of the complete rebuttal to climate science. And, of course, they never will.
68389. Rob Honeycutt at 06:24 AM on 15 December 2011
       CO2 was higher in the past
       adesbarats... Atmospheric CO2 levels are also part of a long term process called the "CO2 Rock Weathering Thermostat." Here is a good article about it. I'm not clear on how much volcanic activity has changed over the past 500 million years but what's really fascinating is you can see in the geologic record almost exactly where the Indian continent started bumping up against the Asian continent to start forming the Himalayas and started a long process where CO2 was pulled out of the atmosphere through rock weathering. And along with that you see the global temperature start a long slow decline from the days where you had crocodiles in the Arctic to modern glacial cycles in the Arctic. All of it a function of the amount of CO2 in the atmosphere. This all fits well with deep glaciation events (Snowball Earth) where the almost complete ice cover of the planet would prevent any rock weathering and thus cause CO2 to build up to very high levels before raising the temperature enough to melt the ice.
68390. KR at 05:53 AM on 15 December 2011
       2nd law of thermodynamics contradicts greenhouse theory
       TOP - I would like to point out that every 'objection' you have raised has been discussed ad nauseum, and shown incorrect, in the previous thousand comments. G&T is a horrible paper, incredibly flawed, and the various "2nd Law of Thermodyamics" objections to the radiative greenhouse effect are simply not valid. At this point I consider the very fact that someone raises such objections to be a clear indicator that the proponent (a) lacks a sufficient education in physics, and (b) will grab onto anything that might even plausibly provide an objection to the science, regardless of validity. It's not (IMO) a promising sign. Please - read the Opening Post (OP), read through the thread a bit, go look at examinations of this topic such as the excellent work at Science of Doom (who has multiple threads on this topic). I think you might find a deeper understanding of this topic worthwhile.
68391. scaddenp at 05:44 AM on 15 December 2011
       Galactic cosmic rays: Backing the wrong horse
       So Eric, in light of this discussion can we assume that you now agree that GCR remain a dead duck? And short of new evidence (as opposed to speculation) that provides a better model than current thinking, policy should be informed by conventional understanding of climate?
68392. KR at 05:40 AM on 15 December 2011
       (Fahrenheit) 451 ppm
       skept.fr - Odd, I don't see a /sarcasm marking in your last post... Climate change is a slow-motion train in progress. Over the next 100-150 years with business as usual (BAU) we're looking at any number of consequences: * No summer ice in the Arctic - loss of albedo increasing heating rates, killing off polar bears, etc. * Loss of most of the Western US pine forests due to migrating pests (in my personal view a terrible shame). * Considerable reduction in crop productivity over much of the worlds currently developed agricultural lands (est. >50% loss in California Central Valley, source of 8% of US produce). * Ongoing conversion of the Amazon into savannah. * Ongoing rises in extreme heat events, droughts, floods. * Sea level rise - perhaps 1-2 meters, perhaps much more. * Loss (by submergence and erosion) of the majority of Pacific atoll islands. * Catastrophic loss of coral reefs (acidification, temperature rise) leading to major extinctions. * Probable collapse of ocean food productivity - see the various ocean acidification threads - as the base of the ocean food pyramid collapses. And these consequences hold whether warming rates are at the high or low end of current climate sensitivity estimates - only slight changes in how fast they hit. And yet - you seem to repeatedly call for "go slow" approaches, to minimize economic shifts or disruption, to 'tone down' the urgency. This despite the (acknowledged) lead time required to shift energy production from fossil fuels. When a train is approaching, it's perhaps wise to get off the tracks!
68393. Philippe Chantreau at 05:28 AM on 15 December 2011
       2nd law of thermodynamics contradicts greenhouse theory
       I'll add to what TC and Muon just said and make one bold statement: the measurements you obtain, considering how your instrument works, are entirely consistent with everything known of atmospheric radiative physics. They do not contradict the GH effect at all. In fact, knowing all the applicable local conditions at the time of measurement, they could be predicted from the physics. I'll leave it to you figure out why and how. You write here with the pretention to demonstrate that current understanding of atmospheric radiative physics is deeply flawed, there is then no doubt that you have the abilities to do that work. Then, you can explain exactly where the flaws are in the process used for the prediction.
68394. CBDunkerson at 05:18 AM on 15 December 2011
       CO2 was higher in the past
       adesbarats, dust and other particulates from volcanic eruptions definitely have a cooling effect, but since these are solid matter (however small) they tend to settle out of the atmosphere within a few years. Indeed, this effect can be seen in climate records where one or two year temperature drops follow major volcanic eruptions. Thus, I don't think they make a good candidate for the cause of longer term 'low' temperatures alongside 'high' CO2 levels. The usual explanation for such past incidents is that the radiation output of the Sun is increasing as time goes by... 400 MYA the Sun was much 'cooler' than it is now. There are many other factors, but solar output, atmospheric CO2 levels, and surface ice albedo seem to be some of the most significant variables.
68395. muoncounter at 05:01 AM on 15 December 2011
       2nd law of thermodynamics contradicts greenhouse theory
       So we're supposed to be willing to overthrow a well-known scientific principle on the basis of one hotly-disputed paper and a backyard experiment. If valid, from such discoveries come Nobel Prizes. The details of that experiment: - A measuring device costing less than $82 (current amazon.com price for a Fluke 62). - "Is it accurate at that temperature? I don't know, never sent it out." - "it is very likely that a simple instrument like this sees a fairly narrow radiation band avoiding the CO2 and H2O absorption bands" -- my IR thermometer has a quoted spectral response of 6.5 to 18 microns, which the figure below shows is not 'narrow band.' - the quoted range of such sensors is 6 feet or less -- works fine for checking AC/heating duct air temp. But if this is a credible experiment, tickets to Stockholm are in order. However, I wonder why NASA goes to all this trouble and expense designing and calibrating real narrow band (centered around 10.8 and 12 microns) IR sensors for satellites. Why not just put up a few hundred dollars worth of retail models? Oh, I forgot, they just do all this to boost their funding. Right.
68396. skept.fr at 05:00 AM on 15 December 2011
       (Fahrenheit) 451 ppm
       For sure, let’s oblige China, India, Pakistan, Russia and neighbors to leave / not exploit rapidly their coal, oil and gas so as to save climate by lowering emissions at 50% of their current level in one generation, because we (responsible citizens without nonsensical and dangerous ideas) are pretty sure this decision will necessarily reinforce peace, security and welfare for these nearly 3,5 billion citizens in 2050. It is well known climate is the only source of war, suffering and death in all human history, as it is well known energy and its correlates in society are just trivial details.
68397. adesbarats at 04:59 AM on 15 December 2011
       CO2 was higher in the past
       This is really great discussion. A question I'd like to pose. As we know, our planet's core is cooling. So presumably, 400 MYA there would have been a lot more volcanic activity then there is today. This volcanic activity, of course, is what likely led to the high atmospheric CO2 levels in the past but my question is this - volcanoes spew alot more then just greenhouse gases. They will also spew dust and other such particles that would have a cooling effect on the earth. As such, could that also explain the reason for high CO2 levels during a period of glaciation?
68398. Roger Gram at 04:46 AM on 15 December 2011
       Is there a case against human-caused global warming in the peer-reviewed literature? Part 3
       There are many skeptical, peer-reviewed papers that you have left out. An example is: A comparison of tropical temperature trends with model predictions David H. Douglass, John R. Christy, Benjamin D. Pearson, S. Fred Singer Int. J. Climatol. (2007) DOI: 10.1002/joc.1651. DOI: 10.1260/095830509787689277. This paper led to a dramatic (and entertaining) clash with RealClimate: http://www.realclimate.org/index.php/archives/2007/12/tropical-troposphere-trends/ and a published reply by Santer, et al: http://onlinelibrary.wiley.com/doi/10.1002/joc.1756/abstract If you look at all of Douglass's 20 or so publications on climate, you will see the theme of skepticism toward human-caused global warming. If you want to list all the skeptic's papers, you need to look more carefully.
       Response:

       [dana1981] You misunderstand the purpose of the search, which is to identify papers which reject man-made global warming.  Papers which dispute some relatively minor aspect, like the rate of warming of the tropical troposphere in your first example, do not make a case for rejecting man-made warming.

68399. Steve L at 04:43 AM on 15 December 2011
       Ocean Acidification: Corrosive waters arrive in the Bering Sea
       Rob, thanks for #6. I'm guessing that #7 has something to do with replaceability -- when aragonite won't do, then they switch to calcite. I read somewhere that different parts of sea urchins use different CaCO3 minerals (tips versus bases of spines?), so it shouldn't surprise us that some animals can switch. Looking forward to more, as usual.
68400. John Hartz at 04:17 AM on 15 December 2011
       Ocean Acidification: Corrosive waters arrive in the Bering Sea
       Also, kudos on your bullet point summary of the article under the heading, "Acid Test." Summaries like yours should be standard fare for all SkS articles. Also, thanks for including the "Related Reading" tab. This simple device makes it much easier for readers to navigate their way through the thick forest of SkS posts.

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