A quantitative assessment of the scientific consensus on anthropogenic climate change

From the abstract to the paper:

… we use an extensive dataset of 1,372 climate
researchers and their publication and citation data to show that (i)
97-98% of the climate researchers most actively publishing in the
field support the tenets of ACC outlined by the Intergovernmental
Panel on Climate Change, and (ii) the relative climate expertise and
scientific prominence of the researchers unconvinced of ACC are
substantially below that of the convinced researchers.

Here are the key graphs from “Expert credibility in climate change,” Proceedings of the National Academy of Sciences (2010). Note that UE denotes unconvinced; CE denotes convinced (by the thesis of anthropogenic climate change).
qa_agw1.gif

qa_agw2.gif

In other words, the climate scientists that are better published tend to be convinced of anthropogenic climate change; moreover, the ones that are better cited also tend to be more convinced of ACC.

 

For those who are dis-inclined to read the article, but are worried about selection bias, here is the method by which the authors selected the sample of climate scientists.

To examine only researchers with demonstrated climate expertise, we
imposed a 20 climate-publications minimum to be considered a climate researcher,
bringing the list to 908 researchers (NCE = 817; NUE = 93). Our dataset
is not comprehensive of the climate community and therefore does not infer
absolute numbers or proportions of all CE versus all UE researchers. We acknowledge
that there are other possible and valid approaches to quantifying
the level of agreement and relative credibility in the climate science community,
including alternate climate researcher cutoffs, publication databases,
and search terms to determine climate-relevant publications. However, we
provide a useful, conservative, and reasonable approach whose qualitative
results are not likely to be affected by the above assumptions. We conducted
the above analyses with a climate researcher cutoff of a minimum of 10 and
40 publications, which yielded very little change in the qualitative or strong
statistically significant differences between CE and UE groups. Researcher
publication and citation counts in Earth Sciences have been found to be
largely similar between Google Scholar and other peer-review-only citation
indices such as ISI Web of Science (20). Indeed, using Google Scholar provides
a more conservative estimate of expertise (e.g., higher levels of publications
and more experts considered) because it archives a greater breadth of sources
than other citation indices. Our climate-relevant search term does not, understandably,
capture all relevant publications and exclude all nonrelevant
publications in the detection and attribution of ACC, but we suggest that its
generality provides a conservative estimate of expertise (i.e., higher numbers
of experts) that should not differentially favor either group.

Now, it seems despite the obvious relevance of global climate change to economic activity, some Econbrowser readers are skeptical of the link. For the skeptics, see these reports:

 

 

94 thoughts on “A quantitative assessment of the scientific consensus on anthropogenic climate change

  1. Thomas

    “No amount of experimentation can ever prove me right; a single experiment can prove me wrong.”
    Albert Einstein

  2. John lohman

    I’m sure research grants and funding have nothing to do with this outcome….. government funded assessment of government funded assessments. Makes sense to me.

  3. Nemo

    I did a similar survey of the opinions of cancer researchers, and I discovered that they overwhelmingly believe that cancer research requires more funding. Stunning!
    (For the record, I believe in AGW. But this may be the stupidest argument in favor I have ever seen.)

  4. Tore Olafsen

    Have you considered the possibility that; (1) the UE researchers started publishing much later as a reaction to the CE papers, (2) the CE researchers have had the IPCC as their billboard since 1990, (3) that the CE researchers are heavily citing each other and (4) it has been difficult for UE researchers to publish their papers? I would suggest that the data you are using is heavily biased.

  5. Ka

    Why is it that the remaining sceptics seem to be concentrated in the Anglo-Saxon world? Outside of that area, the unconvinced are basically seen as hopeless nuts, kinda like creationists

  6. CoRev

    Menzie, a response to the original paper is copied below. This paper had so little impact the furor died almost immediately. Why so late to the party?
    From here: http://wattsupwiththat.com/2010/08/05/expert-embarrassment-in-climate-change/
    Expert Embarrassment in Climate Change
    Posted on August 5, 2010 by Anthony Watts
    Guest post by Thomas Fuller
    The paper Expert Credibility in Climate Change, published in PNAS by Anderegg, the late Stephen Schneider, James Prall and Jacob Harold attempts to measure the credibility of climate scientists by counting how many papers they have published and how often their work has been cited by others.
    This led to the creation of a blacklist that will be used to injure the careers of those who have signed letters or petitions that do not agree with the Al Gore/James Hansen position on climate change, and to intimidate future scientists, effectively silencing dissent.
    The paper is poorly done, as Ive explained elsewhere. They used Google Scholar instead of an academic database. They searched only in English, despite the global nature of climate science. They got names wrong. They got job titles wrong. They got incorrect numbers of publications and citations.
    As Ive mentioned, the highly respected Spencer Weart dismissed the paper as rubbish, saying it should not have been published.
    But the worst part of this is the violation of the rights of those they studied. Because Prall keeps lists of skeptical scientists on his weblog, obsessively trawling through online petitions and published lists of letters, and because those lists were used as part of the research, anyone now or in the future can have at their fingertips the names of those who now or in the past dared to disagree.
    The Joe Romms of this world have already called for this list to be used to deny funding, tenure and grants to scientists. And it will be. It doesnt matter that the nature of the letters and petitions they signed varied widely, from outright skepticism to really innocuous questioning of the state of the science.
    The paper is tagged Climate Deniers. Now, so are they.
    This is an outright violation of every ethical code of conduct for research that has ever been published.
    They violate several sections of the American Sociological Association Ethical Guidelines:
    Sociologists conduct research, teach, practice, and provide service only within the boundaries of their competence, based on their education, training, supervised experience, or appropriate professional experience.
    The members of the research team were operating outside their areas of professional competence.
    Sociologists refrain from undertaking an activity when their personal circumstances may interfere with their professional work or lead to harm for a student, supervisee, human subject, client, colleague, or other person to whom they have a scientific, teaching, consulting, or other professional obligation. The subjects of their researchthe scientists on the listrisk grave harm as a result of this paper.
    11. Confidentiality
    Sociologists have an obligation to ensure that confidential information is protected. They do so to ensure the integrity of research and the open communication with research participants and to protect sensitive information obtained in research, teaching, practice, and service. When gathering confidential information, sociologists should take into account the long-term uses of the information, including its potential placement in public archives or the examination of the information by other researchers or
    practitioners.
    11.01 Maintaining Confidentiality
    (a) Sociologists take reasonable precautions to protect the confidentiality rights of research participants, students, employees, clients, or others.
    (b) Confidential information provided by research participants, students, employees, clients, or others is treated as such by sociologists even if there is no legal protection or privilege to do so. Sociologists have an obligation to protect confidential information and not allow information gained in confidence from
    being used in ways that would unfairly compromise research participants, students, employees, clients, or others.
    (c) Information provided under an understanding of confidentiality is treated as such even after the death of those providing that information.
    (d) Sociologists maintain the integrity of confidential deliberations, activities, or
    roles, including, where applicable, that of professional committees, review panels,
    or advisory groups (e.g., the ASA Committee on Professional Ethics).
    (e) Sociologists, to the extent possible, protect the confidentiality of student records,
    performance data, and personal information, whether verbal or written, given in the context of academic consultation, supervision, or advising.
    (f) The obligation to maintain confidentiality extends to members of research or training teams and collaborating organizations who have access to the information. To ensure that access to confidential information is restricted, it is the responsibility of researchers, administrators, and principal investigators to instruct staff to take the steps necessary to protect confidentiality.
    (g) When using private information about individuals collected by other persons or institutions, sociologists protect the confidentiality of individually identifiable information. Information is private when an individual can reasonably expect that the information will not be made public with personal identifiers (e.g., medical or employment records).
    I think it is clear that the paper, wrong on the facts, is unethical in its intent and outcome. I call for the pape to be withdrawn and for Pralls website to take down the Blacklist.
    Thomas Fuller http://www.redbubble.com/people/hfuller

  7. W.C. Varones

    This is analogous to the widespread failure of credit models to predict strategic default and macroeconomic models to predict the economic crash. You’re ignoring factors that are potentially the most relevant factors.
    One of the key arguments by climate skeptics is that there is groupthink, suppression of dissent, and funding dependent on producing results consistent with the orthodoxy. The East Anglia and UCLA scandals would tend to confirm that argument. If that argument is true, one would expect exactly the quantitative results you’re getting, whether or not AGW is true.

  8. Chris Erickson

    I find these sort of count-the-number-of-researchers-who-say arguments unconvincing. They are in essence hyper sophisticated appeals-to-authority.

  9. RicardoZ

    Menzie wrote:
    In other words, the climate scientists that are better published tend to be convinced of anthropogenic climate change; moreover, the ones that are better cited also tend to be more convinced of ACC.
    Menzie, this is a great sentence. Given the fraud that was perpetuated through the IPCC this says more about the political bias of journals and peer review than it does about the science itself.
    Things haven’t change much. Marie and Pierre Curie were stuck out in a leaking shed for years while their “peers” were in the comfort of the science building working on the same tired old failed concepts. Peer review in science is almost always behind the times, and the accepted opinions of the elite are even more distant from truth.

  10. GregL

    Anybody who takes the time to read the scientific literature and the summary of the literature by NOAA, IPCC, National Academy of Sciences, etc understands the situation well. It is those who refuse to read the authoritative literature that are the problem.
    Among the non-readers, we have two groups: the lazy and the malicious. The malicious mislead the lazy. Thus we need to confront the malicious at their Achilles heel: credibility. This study does just that, and does it well.

  11. C Thomson

    It is hard to understand why climate liberals like Prof. Chinn bother arguing with deniers. Bit like arguing with alien abduction theorists. Or Jesus freaks.
    Surely the argument worth having is whether a world of 9.5 billion people can do anything useful collectively about global warming? Al Gore-style plans for the US alone to make posturing anti-warming gestures are right up there with Prius owning or making your cat a vegan.
    My take is that the best thing is to start ordering inflatables for the Maldives.

  12. hcmi

    Seems to me that there is a positive correlation between climate change and economic activity promoted by governments all over the world. A climate change bubble in the making or maybe we’re there already.

  13. Bruce McCullough

    The “expertise” of the climate “scientists” is often laughable. For example, in the Climategate emails these “scientists” reveal their inability to estimate an ARMA model.
    As to their statistical abilities (which often are laughable, too), see the Wegman report.

  14. Chuck Stubbart

    Ordinary people just don’t trust scientists any more than they trust priests, witches, lawyers, or public officials. People are not moved by the statistics and experiments that sway scholars and scientists. There are just too many voices clamoring for attention in this World. Young people have seen too many movies starring Evil scientists. The authority of science is low, so who cares what 99% of climate scientists think?

  15. nilys

    The contributor and the last author on this paper is the same person, which means it is a Track I paper. From here (http://www.pnas.org/content/102/18/6241.full.pdf): “Members are allowed to “communicate” up to two papers each per annum for nonmembers in their own sphere of expertise via Track I, for which the member procures at least two reviews before submission to the editorial office.” Members are also allowed to “communicate” their own papers through this track.

    In other words, a member sends his own or his friend’s manuscript for review to two of his other best friends, and when he does not like critiques that come back, he could send the ms to other friends until he collects favorable reviews. Versus the regular route, when a journal editor sends a manuscript to whoever she/he pleases to send it (even through some journals encourage you to suggest potential reviewers) and when reviews are negative, that’s the end of it. This “communication” mechanism has caused some embarrassment for PNAS, like for example when PNAS published an article that argued that caterpillars and butterflies used to be two different species that fused together (http://www.pnas.org/content/106/47/19901.full).

    Just because a majority espouses it, it does not mean it is true. In my opinion, it is easier to publish an ms that is consistent with the prevalent ideas espoused by a majority at the time than a finding that questions the prevalent view. Usually, contrary findings first appear in “specialized” journals and then work their way “up” toward acceptance and publication in “high impact” journals.

  16. GregL

    CoRev posts an article that claims a breach of “confidential information”, yet fails to list any such information. The study was based on publicly available data. In deed, the very lists used were (1) the signed contributors to a government report and (2) a public petition signed by people who knew it was public and was public when they signed it. The publication information is from publications; what’s confidential about that?
    Just more misdirection by denialists.

  17. KevinM

    …percent of financial analysts have agreed that buy and hold is the best strategy… clesr concensus … never a better time to buy or sell a house

  18. Menzie Chinn

    CoRev: Don’t think I found the post that Weart said the paper was “rubbish”. Did find the post where he notes a possible bias…but of course, he his judgment is based upon a “quick reading”.

    The authors do not use the label “climate deniers”; they use “climate skeptics”, or in the statistical analysis, are tagged “Uncertain”. They note that this group encompasses what some people call “climate deniers”, once, in the paper.

    With respect to using Google Scholar biasing the results against adducing impact to the UE group completely wrong, given my experience using Web of Science (standard academic citation database) and Google Scholar, the latter captures a much broader set of publications, including books in digital form, and further is faster at catching references. If indeed it is harder for UE authors to get published in standard venues, or have come to publish later — as Fuller as argued, then use of Google Scholar actually helps shift upward the ratio assocated with UE views. This point also bears upon Tore Olafsen‘s critique.

    Chris Erickson: Just consider, each time you drive across a bridge, you are submitting to “appeal to authority”. We can’t be experts in everything. I’d love to be an expert in nonlinear econometrics, but when in doubt I’ll use the code of somebody who does research in the area…

  19. Rod

    Economics is foremost about incentives and how people react to them. What incentives do 1,300+ scientists working independently have in believing in something for which there is no actual evidence of? On the other hand, there is clearly an incentive for some heavily emitting industries to deny whatever evidence may be there. Here’s an example:
    http://www.newyorker.com/reporting/2010/08/30/100830fa_fact_mayer?currentPage=all
    People often do engage in mass delusion and suppress dissenting views, as the most recent financial crisis showed. But incentives matter: a lot of the people who engaged in mass delusion during the crisis where profiting from asset appreciation, and had an incentive to continue believing that certain asset prices could decline.

  20. CoRev

    Menzie, I find the quality of recent AGW research intriguing. Intriguing because it is hard to actually call it research, but more importantly, the responses from the pro-AGW community when it encounters an alternative explanation. Calling it wagon circling would be misstating the reaction. When they have little counter argument, the response becomes one of personal denigration.
    So we see a series of papers such as the one you cite. Circling the wagons is not science.

  21. Menzie Chinn

    CoRev: I didn’t see a rejoinder to my comment regarding Fuller’s errors/mistatements, and GregL points. Since you reproduced approvingly, I had assumed you agreed with his points, and would therefore defend.

    I don’t think of the PNAS paper as a paper on AGW, per se; rather it is a tabulation of views of climate scientists regarding ACC — much like economists have been surveyed, sometimes by their respective professional organizations.

  22. aaron

    What are the tenets of acc?
    The ipcc statements are rather being. If surveyed, I likely would be shown to be in agreement. The tone and policy directive on the otherhand are ridiculous.

  23. CoRev

    Another intriguing result is the administration’s preemptive court filing http://wattsupwiththat.com/2010/08/26/obama-sg-urges-tossing-co2-ruling-greens-howl/ to remove Fed courts as GW policy makers. Why?
    Could it be this? http://wattsupwiththat.com/2010/08/16/new-zealands-niwa-sued-over-climate-data-adjustments/
    or VA Atty Gen. Cucinelli’s filings against Mann and the many other states filing similar cases against the EPA findings?
    It was OK to file when it meant getting a positive ruling for AGE, but now, there is a growing use of those tactics against AGW. Whoa!!! We can’t have that! Lose one and lose all pro-AGW rulings?
    After having over reached, it’s now time for that ole pendulum to swing back. As it always does.

  24. colonelmoore

    Why is it that everyone proposes that we tear our energy economy out by the roots because there is a scientific consensus that the upward temperature trend from the 1970s to the 1990s was caused by manmade carbon emissions?
    Can economists and scientists reach a consensus as to whether it would be better over the short and medium term to deal with it at the sink rather than the source while carefully developing cost-effective and safe formes of alternative energy?
    When I see something that on its face doesn’t make sense, I fall back on the maxim, “Follow the money.” Money can buy a lot of things including suppression of good ideas.
    “Nuclear power in Australia would not be able to compete with coal fired power stations without
    carbon emission controls,” according to a report to the Australian Radiation Protection and Nuclear Safety Agency. http://www.arpansa.gov.au/pubs/nsc/nsc_feb07.pdf

    Part of the reason for distrust of the scientists is that people see so much money being bet on technologies that cannot compete without some form of subsidy. GE owns NBC, which regularly does weeklong green pitches. GE is one of the biggest players in nuclear power. Similarly, the utilities that are calling for cap and trade all have major investments in nuclear power.
    How much money would GE or Exelon make off of a worldwide effort to reverse deforestation?
    Economists can provide useful input by comparing the economic costs and benefits (especially comparing the effects on the poorest nations) of efforts to regulate carbon at the sink versus the source. The fact that such comparisons are not done or if done are being ignored makes me think that funding is much better for studies on how to remake our energy infrastructure.

  25. Bryce

    An interesting post. The use of the word ‘skeptic’ is so much to be preferred to ‘denier,’ if you hope to persuade the skeptic.
    & we must never forget that there was a time when the scientific community was convinced that combustion had something to do with phlogiston rather than oxygen.

  26. CoRev

    Menzie, we’re in shoot the messenger mode now?! If you have a complaint about the article I COPIED.
    I reread GregL’s comments. The first was just another rant which I ignored accordingly. The latter was another attack of what is now an attack of the article I COPIED. What’s the point in responding for an author that I do not converse.
    BTW, the answer is yes. I do agree with Fuller’s review of the PNAS paper.
    As an aside, I visited J Prall’s site for the first time as a result of your article, and found it to be typical for pro-AGW bloggers. He too requires lock-step agreement with his views or he erases your comment. Thank-you and James for not falling into that trap.

  27. uber_snotling

    Menzie and others,
    Credibility: I have a PhD in atmospheric science/physical chemistry from UC Berkeley and have published over 15 peer-reviewed articles in the field. I beg you all to back off, because I am a SCIENTIST!
    Unless you have personally read the relevant scientific literature, including the IPCC reports and the various scientific articles they are synthesized from, you are incapable of making an informed judgment on global climate change. Some of you such as CoRev are amateur atmospheric scientists, following blogs and reading reports; I am an amateur economist in much the same way.
    Given my years of experience in reading economics blogs, I consider myself capable of developing ideas and thoughts about economics, despite my lack of formal training. And I can see that the economics profession has a lack of predictive capability for many of the key problems it tries to produce answers for. But I don’t go around arguing that the Austrians are wrong or the New Keynesian models suck, because I certainly don’t have the expertise to do so.
    I would like to encourage those not trained in the area to back off and let us scientists do our jobs. If scientists can prove that climate change is wrong, false, or much smaller than predicted, they’ll win lots of awards. I firmly believe that, because scientists love to rip each other’s stuff apart as it tends to be good for career advancement. Also, while science does get stuck in the wrong idea sometimes, we’ve got a planet-wide experiment going on that we can use to continue to tweak our understanding.

  28. GregL

    CoRev,
    If you post an article you’re responsible for it. The article would not have been visible here except for your actions; accept the responsibility for what you post even if they are not your words.
    As to my comments on the article, since you didn’t respond to the points I made (you only recognized that they were critical of your posting) we can all assume that you have no defense to present of the criticism.

  29. CoRev

    GregL said: “…we can all assume that you have no defense to present of the criticism.” Absolutely true! I do not intend to take each article apart line by line. You go ahead, though!
    UberS said: “…you are incapable of making an informed judgment on global climate change. Some of you such as CoRev are amateur atmospheric scientists, following blogs and reading reports; I am an amateur economist in much the same way.” I dunno about the not being able to make an informed judgment. The reason i say this is because most of the public rhetoric is political and not scientific. See the referenced ?scientific? report which is the subject of Menzie’s article.
    UberS also said: “Also, while science does get stuck in the wrong idea sometimes, we’ve got a planet-wide experiment going on that we can use to continue to tweak our understanding.” I agree completely, but (yes, there’s always a but) the time frames are just wrong. The experiment you are referencing will take decades to resolve, but the economic reactions to it are already well underway. The risk associated with these reactions is the problem, and exceed the possible negative ramifications of the science being proven true. We are looking at immediately (or at the very least in the near term) devastating economies in order to fight/forestall some unproven impacts in 1-2 centuries.
    If we stuck to discussing the science then it would be a focused and limited discussion, but, alas and alack, we do not. We are trying to solve a scientific concern via a political solution. In the political arena we all are or can be experts.

  30. Barkley Rosser

    As someone who has personally known some of the leading “deniers” for decades, two points.
    1) It is highly likely that some of the people who are being classified as “deniers” are not. Quite a few of these folks have changed their views in recent years, although now arguing that warming is likely to be less than the median of the IPCC range of forecasts. An example would be the very prominent Patrick Michaels.
    2) There really was a time when the balance of publications was nearly evenly split between pro-warming and pro-cooling. This was in the early 1970s, when, for example, later “pro-warmer,” the recently late Stephen Schneider famously published a paper in 1971 suggesting that it was up in the air whether the cooling effect of more particulates would win out over the warming effect of more CO2. He changed his mind a few years later as better data and modeling came in, even though it was not until after the mid-1970s that average global temperatures began to rise. There has since then been a long steady drip of former deniers figuring it out and changing their views, even if public opinion in the US has actually tilted away from the now nearly universally accepted view (BTW, Menzie, some of the leading “deniers” came out of UW, including Michaels, students of the late Reid Bryson, who died somewhat over a year ago).

  31. Bruce McCullough

    IT is most interesting that Menzie adduces bridges in his argument: Just consider, each time you drive across a bridge, you are submitting to “appeal to authority”.
    I was just reading Sowell’s “Intellectuals and Society” and came across this directly relevant quote (p. 144): “A scientist who filtered out facts contrary to some preferred theory of cancer would be regarded as a disgrace and discredited, while an engineer who filtered out certain facts in building a bridge could be prosecuted for criminal negligence[.]”
    We are well aware, via Climategate, that the climate “scientists” engaged in such filtering on a massive scale. Hmmmm. If they were only engineers….

  32. tj

    uber,
    Chastisement noted.
    Asking John Q. Public to trust the experts is akin to Pelosi’s quote that we will have to wait for the health care bill to pass in order to find out what is in it.
    http://www.youtube.com/watch?v=KoE1R-xH5To
    We all know how that turned out. Progressives run red-faced to the powder room every time embarrassing pieces of the legislation are brought to light.
    As a skeptic and admitted simpleton, we want you to educate us.
    We don’t understand why we should attribute the entire trend increase in temperature anomaly over the past few decades to man-made CO2, and only mad-made CO2.
    You see, the way we simpletons look at it, is that once you account for all the other human forcings, in addition to the unaccounted natural forcings, there will be little variation in temperature left for CO2 to explain.
    So we ask the question, “Is The Human Addition Of Carbon Dioxide The Primary Human Climate Forcing?”
    http://pielkeclimatesci.wordpress.com/2009/12/16/q-a-is-the-human-addition-of-carbon-dioxide-the-primary-human-climate-forcing/
    contains several references to peer reviewed answers that discredit the alarmists’ claims that if we don’t “necessarily cause utility bills to skyrocket,” the sky will fall, the ice caps will melt and sea levels will rise to the point where the entire U.S. population will be forced to subsist on a small rocky hill in Kansas.
    Please enlighten us on how we can be confident that the models, of which we are ignorant, are not attributing the bulk of temperature change to CO2 when the literature identifies numerous forcings that the models don’t include. I wonder how many forcings are yet to be identified?

  33. Steve Bannister

    Menzie, this paper may be of (methodological and topical) interest to you. I have not yet read it as carefully as it deserves, but the methodology looks interesting. Of course, no matter how credibly done, the results will not please some people.
    Kaufmann, Robert, Heikki Kauppi, and James Stock. 2006. Emissions, Concentrations, & Temperature: A Time Series Analysis. Climatic Change 77(3): 249-278. Available at: http://dx.doi.org/10.1007/s10584-006-9062-1 [Accessed June 25, 2010].

  34. djt

    I’m not a climate scientist but I’m sure Exxon has tried to do the following.
    A full page ad in the NYT, LAT, and WSJ costs, each, about $50,000 per day. So for $1.5 million, Exxon could run a full page ad in each paper for two weeks.
    A graduate student in climate research gets, say, $50,000 per year in net salary. Exxon could pay them, say, $1,000,000 for one year to create the content for those 10 days of ads. Each day would reveal the dead bodies, the statistical errors, debunk the greenhouse effect, etc. So for $2.5 million, Exxon could put this issue to rest.
    Why haven’t they? Why hasn’t any of scores of companies with $2.5 million done this? Or even the Chamber of Commerce? Why not?

  35. Rob

    CoRev,
    I enjoy reading your posts so please take this as a question for you and the audience:
    ” …The risk associated with these reactions is the problem, and exceed the possible negative ramifications of the science being proven true…”
    I *think* that in this scientific endeavor (climate research) they are postulating a null hypothesis (e.g. mankind causes global warming) and attempting to prove it false, i.e. reject the null. I don’t think the effort it to prove it true, just with increasing precision (according to their models) not be able to reject the null. (fully admit I could have this backwards)
    And therein lies the rub so many have? Simply, if we can’t trust what the weatherman says on a daily basis, how can we trust a much more complicated model? It seems to me quite obvious that pumping CO2 into the atmosphere via burning fossil fuels formed by plants/microbes that removed CO2 from the atmosphere long ago– we should be warming up the planet & acidifying the oceans. But I also know that the earth has gone through inter-glacial periods of warming before… It’s complicated to say the least but one could argue that all models are wrong or incomplete (except if you’re taking them to dinner)

  36. Anonymous

    I think if you do this type of assessment in 1500s regarding the shape of earth, you will get similar result proving the earth is in deed flat.

  37. CoRev

    djt said: “Why haven’t they? Why hasn’t any of scores of companies with $2.5 million done this? Or even the Chamber of Commerce? Why not?” I suspect it is because of a potential conflict of interest at this late date and they wouldn’t be believed anyway.
    Remember, the inevitable claim is that all skeptics are funded by “Big Oil” to create doubt and confusion. BTW, I’m still waiting for my check, as is everyone I talk to.
    Regardless, which issue do you want resolved? There are so many, that it has become mind boggling to track the claims of ACC impacts.

  38. Barkley Rosser

    Bruce M.,
    Anybody claiming that “Climategate” shows that scientists arguing that there is global warming were “filtering out facts” or skeptics has not read the public record and is relying on loud-mouthed and regularly lying commentators on TV and radio, not anybody serious.

  39. Steve Bannister

    Menzie, this paper may be of (methodological and topical) interest to you. I have not yet read it as carefully as it deserves, but the methodology looks interesting. Of course, no matter how credibly done, the results will not please some people.
    Kaufmann, Robert, Heikki Kauppi, and James Stock. 2006. Emissions, Concentrations, & Temperature: A Time Series Analysis. Climatic Change 77(3): 249-278. Available at: http://dx.doi.org/10.1007/s10584-006-9062-1 [Accessed June 25, 2010].

  40. Steven Kopits

    I’m not sure I would over-stress the ‘consensus’ idea.
    To my understanding, there is a reasonable amount of consensus that:
    – the planet has warmed since 1880
    – CO2 is increasing by 2 ppm/year, mostly likely from anthropogenic sources
    – CO2 may be contributing modestly to warming
    There is no consensus that:
    – warming is necessarily bad (we’ll known that when people move from Florida to New York, from Arizona to Wisconsin)
    – that there is some ‘tipping’ point at which the planet cooks (CO2 has been much higher in the historical record, at some times with lower temperatures)
    – that CO2 is the dominant source of warming (as temperatures, as measured by UAH satellite data, have not risen since 1998, even though CO2 has)
    – that policies to reduce CO2 are worth the effort or cost, or even feasible in any realistic way
    In any event, I think we’re coming into an interesting period. As we’re moving off last year’s El Nino, temperatures have begun to drop (again, UAH data). If the UAH temp anomaly falls back to the 0.2 deg C level as AGW skeptics expect, then the believers will be facing headwinds; on the other hand, if the anomaly stalls around 0.45 deg C or thereabouts for the remainder of the year, then the believers will enjoy a resurgence. So I think we have a pretty good quantitative test for the balance of the year.
    Having said that, I find the exclusive focus on climate change misplaced. I happened to pick up a copy of Paul Greenberg’s Four Fish last night. It’s a terrific little book, documenting the absolute devastation of fish stocks occuring beneath the ocean’s surface. I find it discomfiting that we spend so much effort on climate change, with all the prognostications inevitably qualified with ‘could’, ‘might’ or ‘may’, when we have huge natural resource issues in the oceans that are crying for attention now. Whatever climate change’s merits may be, it is by far not the only critical environmental issue.

  41. W.C. Varones

    Barkley Rosser,
    I suggest you go back and read the Climategate docs. Here is just a very brief summary.
    They did indeed manipulate, hide, and destroy data, and they did indeed coordinate to suppress opposing views.
    Whether or not AGW is real, a lot of the people behind it certainly act more like ideologues with an agenda than scientists seeking truth.

  42. CoRev

    Rob said: “I *think* that in this scientific endeavor (climate research) they are postulating a null hypothesis (e.g. mankind causes global warming) and attempting to prove it false, i.e. reject the null. I don’t think the effort it to prove it true, just with increasing precision (according to their models) not be able to reject the null. (fully admit I could have this backwards)”
    I’ve not seen it presented quite like this before, accordingly, I believe you do have it wrong. The core of the hypothesis is the Green House effect (GHGs) cause warming. That’s not actually disputed. Then we go off the deep end on how much warming is caused by GHGs? What percentage of that GHG warming is anthropogenic, as there are many other ACC forcings? How much of that warming is natural? What percentage of natural warming is from GHGs and other natural sources? (The list gets quite long here.)
    These are just representative core question that are still unanswered with the processes ill defined. Once we can definitively answer these questions and define their associated processes we can go forward. Creating panicked political responses to these unknowns makes no sense.

  43. 2slugbaits

    Menzie And keeping with the econometric theme, and keeping with the same authors doing another study, and keeping with a previous discussion concerning stationarity, try this:
    http://www.springerlink.com/content/vl6g4g28v8215004/
    Abstract: We evaluate the claim by Gay et al. (Clim Change 94:333349, 2009) that surface temperature can be better described as a trend stationary process with a one-time permanent shock than efforts by Kaufmann et al. (Clim Change 77:249278, 2006) to model surface temperature as a time series that contains a stochastic trend that is imparted by the time series for radiative forcing. We test this claim by comparing the in-sample forecast generated by the trend stationary model with a one-time permanent shock to the in-sample forecast generated by a cointegration/error correction model that is assumed to be stable over the 18702000 sample period. Results indicate that the in-sample forecast generated by the cointegration/error correction model is more accurate than the in-sample forecast generated by the trend stationary model with a one-time permanent shock. Furthermore, Monte Carlo simulations of the cointegration/error correction model generate time series for temperature that are consistent with the trend-stationary-with-a-break result generated by Gay et al. (Clim Change 94:333349, 2009), while the time series for radiative forcing cannot be modeled as trend stationary with a one-time shock. Based on these results, we argue that modeling surface temperature as a time series that shares a stochastic trend with radiative forcing offers the possibility of greater insights regarding the potential causes of climate change and efforts to slow its progression.
    Bruce McCullough You said: “For example, in the Climategate emails these “scientists” reveal their inability to estimate an ARMA model.
    I think you’re misspecifying the right model. The issue isn’t whether or not temperatures are increasing…hell, even CoRev concedes that global temperatures are warming. The issue is whether or not warming is manmade due to CO2 emissions, and you don’t answer that question with a univariate ARIMA model. A better candidate would be VAR model that allows for feedback effects. I believe you’ll find that a very simple unstructured VAR will show you that CO2 shocks have a persistent effect on temperatures, but not so much the other way around. And it turns out not to matter much how you do the Choleski ordering.

  44. 2slugbaits

    Menzie said: “…it seems despite the obvious relevance of global climate change to economic activity, some Econbrowser readers are skeptical of the link.”
    Global warming skeptics are always quick to point out the costs of wrongly assuming that manmade global warming is true and then finding out 100 years later that the science was all wrong. Okay, fair enough. But perhaps skeptics ought to think about the costs of their being wrong and finding out 100 years hence that manmade global warming was indeed true. This is not just a purely science issue; it’s also a public policy issue and that means we have to make decisions based on less than perfect information. There are plenty of economic studies (and here I mean actual academic studies, not the nonsense posted on some amateur’s website) that clearly demonstrate there is no upside to global warming. It hurts exports of poor countries. It hurts agricultural crops. It hurts property values of coastal cities. It hurts fishing and marine husbandry. And the Pentagon & CIA seem to believe that it is likely to cause wars in 3rd world countries. In the spirit of Menzie’s post, skeptics might want to scroll through the NBER database of working papers on global warming. Try and find some studies that conclude global warming is a good news story in terms of economics. Good luck with that. If you want to hear that global warming is a good thing, then I guess you’ll have to listen to noted scholar and Nobel Prize winning economist Rush Limbaugh.

  45. Bruce McCullough

    Barkley,
    you write, “Anybody claiming that “Climategate” shows that scientists arguing that there is global warming were “filtering out facts” or skeptics has not read the public record and is relying on loud-mouthed and regularly lying commentators on TV and radio, not anybody serious.”
    There’s so much….Where to begin? How about, “Hide the decline.” After you attempt to demonstrate that they really weren’t trying to hide the decline (and presumably fail to do so), I’ll give you another example of filtering that you can try to debunk.

  46. 2slugbaits

    tj “Please enlighten us on how we can be confident that the models, of which we are ignorant, are not attributing the bulk of temperature change to CO2 when the literature identifies numerous forcings that the models don’t include.”
    No one is confident in the models…that’s why those of us whom you would consider “alarmists” focus so much on the role of model uncertainty. The difference is that I am formally trained in risk management (I’m an ORSA guy with the Army) and you’re not. So in my world uncertainty doesn’t mean variability around a mean; it means not even being able to confidently estimate the mean. And uncertainty means you get fat tailed distributions (e.g., Student’s t) rather than thin tailed normal distributions. With a normal distribution you can essentially ignore tail events more than a few deviations away from the mean…but you can’t do that with fat tailed distributions. For folks like you and CoRev model uncertainty seems to give you permission to go ahead and believe the best case scenario; for me model uncertainty with extreme events in the 5% tail is “hair on fire” panic time.
    And no one is saying that all of the observed temperature increases are due to manmade global warming, but remember just a few years ago CoRev and his ilk were even denying that there was global warming. Now he’s at least willing to concede that the earth is getting warmer…just not because of humans. The climate sensitivity factor to CO2 concentrations is a big unknown, but what is not unknown is that CO2 does cause global warming. You can prove that in the lab. And quantum mechanics predicts this. So we know that given enough CO2 things will eventually go bad. And we know that CO2 persists in the atmosphere for 100+ years, so we don’t have the luxury of waiting a few months for a final scientific verdict before we commit ourselves. What we don’t know is whether catastrophe is 150 years away or 250 years away, but we do know that if we sit on our duffs long enough there will be catastrophe. The timing is in doubt, but not the ultimate outcome if we do nothing.

  47. Phil's Dad

    So those who consider ACC a priority publish most on ACC and those who consider it less alarming publish more on, well, other things.
    The point being…?

  48. W.C. Varones

    If AGW is real, why do so many global warmists eat meat? Meat production generates far more CO2 than clean American transportation and industry. And giving up meat is far easier than giving up transportation or work.
    Anyone who pushes AGW and still eats meat is at best a hypocrite.

  49. CoRev

    2slugs said (after taking my name in vain): “The climate sensitivity factor to CO2 concentrations is a big unknown, but what is not unknown is that CO2 does cause global warming. You can prove that in the lab. And quantum mechanics predicts this. So we know that given enough CO2 things will eventually go bad. And we know that CO2 persists in the atmosphere for 100+ years, so we don’t have the luxury of waiting a few months for a final scientific verdict before we commit ourselves.”
    What logical fallacy is this? climate sensitivity factor to CO2 concentrations is a big unknown,… but then following with this is typical of the AGW religious believers So we know that given enough CO2 things will eventually go bad. From a big unknown our faith shows us that eventually things are going bad. But, jumping to his final conclusion: “…but we do know that if we sit on our duffs long enough there will be catastrophe. The timing is in doubt, but not the ultimate outcome if we do nothing.”
    And, this kids is how we get to the disastrous policy making this administration wants us to undergo. One actually minor unknown quantity (how much warming is attributable to ACO2?) is exaggerated into a future (centuries away) catastrophic event which requires immediate action that far exceeds the future potential risk.
    Sheesh! 2slugs. Sheesh.

  50. WC Varones

    Correction: should have said AGW gases, not just CO2. Meat production also produces nasty stuff like methane, not just clean, beautiful, organic CO2 which nourishes the rainforest.

  51. 2slugbaits

    Steve Kopits “…we have huge natural resource issues in the oceans that are crying for attention now. Whatever climate change’s merits may be, it is by far not the only critical environmental issue.”
    Fair point, but don’t you think that it’s more than a little revealing that the same folks today who are denying global warming are the same folks who only yesterday were denying that the world’s fish stocks were threatened? Remember? It’s the same people who were right about fish stocks who are now alarmed about global warming. And it’s largely for the same reason…fish stock skeptics and global warming deniers can’t do math. And just to top it off, our friend CoRev also believes that opposition to DDT to kill mosquitoes is wrongheaded…apparently CoRev missed that differential equations lecture about the Volterra principle.
    But since you brought up fish stocks, there’s pretty good evidence that CO2 is a threat to marine life in general and shellfish in particular.

  52. Bryce

    I’ld like to compliment Steve Kopits on his succinct summary of consensus.
    And to point out to slugbaits that it was the same people who wanted to inflict socialism for reasons other than GW before… who now want to do it now “because of GW”.

  53. CoRev

    2slugs said: “there’s pretty good evidence that CO2 is a threat to marine life in general and shellfish in particular.” And this kids is how we jump from one catastrophic prediction (“…but we do know that if we sit on our duffs long enough there will be catastrophe. The timing is in doubt, but not the ultimate outcome if we do nothing.”) to now we are killing our fish by too much CO2.
    From some ill defined centuries away future catastrophe he shifts to today’s latest issue, fish. Remember it’s all in the math and science.
    No! It’s not a religion! It’s blind faith.
    And they wonder why we have questions?

  54. Ivars

    No link to human activities. Its all caused by changes in the Sun. Not the first time in the Earth history. Kind of obvious. Who cares about those who spend resources trying to prove political agenda? They themselves.

  55. 2slugbaits

    CoRev It was Steve Kopits who first brought up the problem of fish stocks. I simply pointed out that it was the same knownothings of yesteryear who denied fish stocks were in trouble that are today denying global warming. Your crowd has a history of being wrong on complicated issues.
    Your arguments about how much we know and don’t know about climate science are hopelessly inconsistent. You’re all over the ballpark on the question just as you used to be all over the ballpark on the question of whether or not the globe was warming. If you don’t think there’s uncertainty about the climate’s temperature response coefficient to CO2 emissions, then tell us exactly what it is and how you calculated it. We’ll all be waiting for your answer.
    “From a big unknown our faith shows us that eventually things are going bad. But, jumping to his final conclusion” This is another example of your inconsist arguments. Here you take issue with my point that even though we may not know exactly where the GHG tipping point is, we do know that at some point there is a tipping point. But this directly contradicts a statement you made a few posts earlier: “The core of the hypothesis is the Green House effect (GHGs) cause warming. That’s not actually disputed.” Let me repeat that last sentence: “That’s not actually disputed.” Now try and explain away this apparent contradiction. So apparently we both agree that GHGs cause warming; the only point of disagreement is the sensitivitiy factor. I say that that there is a great deal of plausible uncertainty around that factor. You on the otherhand seem to believe you know exactly what that factor is. If so, let me urge you to submit your research to a peer reviewed journal. Otherwise concede that there is uncertainty about the parameter and follow me down the path of decision risk analysis in a world of fat tails.
    “From some ill defined centuries away future catastrophe he shifts to today’s latest issue, fish. Remember it’s all in the math and science.” So now you agree that it is at least a risk some ill-defined centuries away? Good. Now do you also recognize that the CO2 lag is also measured in centuries, so if we want to avoid a problem in 2150 we have to act today? As to the math and science, yes it is all there. And by the way, the problem of finding the maximum fish harvesting rate actually is one of those classic textbook problems that you can find in just about any introduction to differential equations textbook. Likewise with the predator/prey model of mosquitoes and DDT. And I’ve read enough climate of physics textbooks to to know that if you CoRev do not understand the math in those models, then you CoRev do not understand the math or science behind climate change.
    BTW, did you ever give us an actual defense of that Thomas Fuller paper you cited? You seemed to be running away from having to defend it, although you still seem to embrace it. Sounds like faith-based global warming denial.

  56. 2slugbaits

    Bryce “And to point out to slugbaits that it was the same people who wanted to inflict socialism for reasons other than GW before”
    Really? And here all along I thought it was the old socialist countries that were some of the worst offenders when it came to worshipping at the temple of economic growth. I was always taught that it was the Russians and old Soviet bloc states in eastern Europe that didn’t give a fig about the environment as long as dumping pollution and CO2 into the atmosphere contributed to economic growth. So are you saying that the old Soviet policies were right and that us green types are all wrongheaded socialists? Oh wait, I thought that the Soviets and Chinese were supposed to be the socialists? I’m so confused. Or maybe it’s your thesis that’s confused.
    I know what would help here. Maybe if you took a course in market economics you would understand that GHG emissions are a negative externality and that in a capitalist economy in which price and output quantity are determined by market forces you end up with inefficient price and output results if some of the costs of production are not fully internalized in the price. In other words, if the government does not correct a market failure you essentially end up with an inefficient price/output result just as you would in a centrally planned command economy. You don’t seem to be aware of it, but you are actually arguing for a command economy in which costs are not fully internalized in the price…i.e., you are arguing that the government should effectively subsidize carbon based energy. I’ll bet you didn’t know that.

  57. CoRev

    2slugs, got caught out again! Why deny that you are making those jumps in faith to get to your conclusions?
    You cite estimate (some made with absurdly huge assumptions) like your reference to a 5% chance as fact! That’s faith based. You cite the acidification studies (originally based upon an aquarium-based experiment where they pumped in abnormally huge amounts of CO2) as they are fact. That’s faith based. You then cite the lowering fish harvesting rate and link it AGW and not over fishing. That’s faith based.
    My favorite reference of yours is the “optimal growth temperature” study. Yup! No question plants have an optimal temperature RANGE, and they usually spend some period of their lives within that range. No mention of other optimal conditions which might actually be more important. Citing only the temperature is faith based.
    We can do this all day. But, why bother? Can’t change a mindset based upon faith. Faith supersedes the science and math. Just look at your references, and repeated citing of them.

  58. 2slugbaits

    CoRev ” You cite estimate (some made with absurdly huge assumptions) like your reference to a 5% chance as fact!” Ummmm…the estimates are a fact. They are based on stochastic simulations and studies typically report the 5% tail event. That’s how models work. For example, “Uncertainty, Climate Change and the Global Economy,” http://papers.nber.org/papers/14426. This paper does 10,001 stochastic simulations of an updated RICE model and reports histograms and fantail charts of simulation results at the 5% and 1% tails. Or how about “Climate Change and Economic Growth: Evidence over the Last Half Century” http://papers.nber.org/papers/w14132? Don’t like that one, then try “Climate Shocks and Exports,” http://papers.nber.org/papers/w15711. All of these papers look at the tails. That’s how it’s done.
    “No question plants have an optimal temperature RANGE, and they usually spend some period of their lives within that range. No mention of other optimal conditions which might actually be more important.”
    First, you’re the one who first made the claim that global warming was good for agriculture. I simply pointed out that your understanding of agronomy leaves something to be desired. Second, when you’re trying to analyze the effects of something like temperature the usual procedure is to try and fix all other variables. You’re looking for change in plant growth with respect to a change in temperature holding other variables constant. That’s how you do partial equilibrium analyses. What’s faith based is to assume that you can ignore the effect of temperature because there are so many other factors that they will cancel out temperature effects. You are the one who is engaged in faith based analysis. You are the one who blindly assumes that other stuff in the earth’s climate system will balance things out and all will be well. That’s faith based.

  59. CoRev

    2slugs, remember, I’ve read your studies. My analysis stands. your 5% tails study requires/assumes absurdly large inputs of CO2.
    Your first agronomic studies were not awfully well controlled as you imply. Regardless, as for plant growth, unless they are in greenhouses with artificial environments including lights, they are not controlled. Your originally referenced study was not in such an environment.
    What amazes me about your agronomic studies is your obvious misunderstanding of how agriculture actually works. Commercial agriculture (including aquaculture) lives outside the optimum(s), think seasons.
    As you said once, you wish to stabilize the climate at some fictional optimal average. An average that was or can only be here momentarily? Probably.
    You’re getting more and more desperate. I’m done here. It’s just too pretty of a day.

  60. 2slugbaits

    CoRev “I’m done here. It’s just too pretty of a day.” Translation: You’re off to the Glenn Beck rally.
    You need to reread the ag studies. They were large panel studies with lots of instrumental variables to choose from, so as a practical matter there was no major identification problem. And the boyz at New Pioneer do explicitly control for factors in their labs and they will tell you the same thing. Go ask them about corn…I did (my in-laws are northern Iowa farmers).
    The point about agriculture is that plant yields fall off at an increasing rate beyond a certain threshold and we are already very close to that threshold. The effect on the US would probably not be too severe, but the effect on Africa and parts of Asia would be devastating. The main victims of global warming will be poor countries.
    Oh, we’re still waiting for that defense of the Fuller paper.

  61. tj

    2slugger,
    You danced around the FACT in my last post that alarmists conveniently ignore all the other man-made contributions to global warming. Once you account for all the other man-made forcings, then the contribution of ACO2 does not merit a huge carbon tax. It is naive to attribute the total residual warming to ACO2, when the literature provides plenty of additional sources that are conveniently ignored by policy makers.
    You also ignore the fact that your lab tests show a logarithmic relationship between additional CO2 and temp change. Eventually, the effect of CO2 on temperature asymptotes so that additional increments of CO2 have little effect on global temps.

  62. 2slugbaits

    tj Most of the stuff that I’ve read does deal with other forcing factors…but their effect is relatively small. And the big one that should have everyone scared isn’t just CO2, it’s methane. One of the big concerns is that CO2 warms up the atmosphere just enough to thaw permafrost and unlock trapped methane. Now that’s a doomsday scenario if there ever was one because methane is a more potent GHG by orders of magnitude. But you might want to think about a logarithmic temperature response to an exponential increase in CO2. I saw something the other day where the latest mean CO2 concentration for the year 2105 was just a little north of 1000ppm, with a 5% tail at ~1250ppm. That’s within the lifetimes of many people living today. This study was based on expected CO2 concentrations assuming population growth rates and Cobb-Douglas total factor productivity rates based on UN data and Penn World Tables. Mean global GDP was estimated to be around $600T (1990 $US). The range of CO2 outputs depended a lot on how Russia and eastern Europe responded. Historical data for those regions ain’t so good and they haven’t shown a lot of willingness to adopt low carbon technologies.

  63. Bryce

    slugbaits, are you purposely being obtuse? Surely you understood my meaning that Al Gore & friends wanted to increase taxes & gov’t control before they discovered the excuse of GW.
    I’m open-minded on GW. But I’m skeptical of anything that comes out of the mouth of Al Gore & his ilk.

  64. Barkley Rosser

    BM and Varones,
    Right. Out of thousands of emails, this was the most “damaging” anybody could come up with. This has all been investigated and found to amount to a big fat zero. “Trick” is regularly used in discussions of econometrics, not to mean to “trick” people, but as a description of an econometric technique. Or are either of you aware of this?
    BTW, one of the people I know, and have since the early 1970s at Wisconsin, is Patrick Michaels, the guy supposedly to be beaten up. This is just so much heated rhetoric. Pat is a vigorous debater, but in fact Pat accepts that there is global warming and that AGW is for real. He just thinks it is going up in a straight line, not as fast as some others think.
    Of course, I suspect neither of you were aware of that either, were you, so excited to quote year old hysterical ninniness out of the Daily Telegraph. What a joke, and completely out of it.

  65. Rinaldo

    I would suggest to conduct another study and research: What are the probabilities that a pro (CE) AGW publication is being published vs an anti AGW publications and what are the benefits in terms of income for the authors in both camps.

  66. 2slugbaits

    Bryce Then my advice is to pretend that Al Gore never existed and ask yourself whether or not a carbon based tax (or its equivalent, cap & trade) makes sense regardless of whose idea it is. Even President Bush’s former chief economist Gregory Mankiw is on board with some kind of carbon tax…hell, he’s more than on board with it, he’s leading the charge with his Pigou Club.
    As to government manipulation of the market, you would be hard pressed to find someone more guilty of that than Dick Cheney. He built his whole fortune on rent seeking activities. I seriously doubt that Bush or Cheney have one-tenth the understanding of market economics as does Al Gore. You want an example? Let’s look at the way Al Gore defended NAFTA compared to the way Cheney and Bush argued for CAFTA. Gore defended NAFTA in a way that almost any economist could understand; he framed NAFTA in terms of a trade triangle. Do you remember the televised NAFTA debate between Al Gore and Ross Perot? Try to imagine that same debate between George Bush or Dick Cheney and Ross Perot. Granted, it was pretty nerdy television viewing for prime time across the networks, but Gore got the economics right. Now turn to the bogus arguments used by Team Bush to defend CAFTA. They didn’t talk about trade triangles, they framed the arguments for CAFTA in what were basically mercantilist talking points. So trying to tell us that Gore is some kind of closet socialist while Bush and Cheney were defenders of free markets is a real kneeslapper. You need to understand that there is nothing “pro-market” about de facto government subsidies for inefficient price and output results. There is nothing “pro market” about not taxing negative externalities.

  67. CoRev

    Barkley, dendroclimatology has been pretty much devastated with later studies. When the confidence levels are so low to make noise an equal signal, then the trick becomes more than just another methodology used in an unrelated field. A discussion of the recent paper, pro & con, can be found here: http://wattsupwiththat.com/2010/08/17/breaking-new-paper-makes-a-hockey-sticky-wicket-of-mann-et-al-99/#more-23450
    I know of few serious ACC skeptics that do not believe that there is warming and some warming is caused by mankind. The real question is how much, and what is the processes? Y’ano that ole basic understanding of climatology? That understanding now resides in a series of papers which is implemented in the various models. Models that are so poor, that their use is via averaging an ensemble of results.
    Recent studies show the models to be 2-4 times to high in their predictions. The paper can be found here: http://rossmckitrick.weebly.com/
    2slugs, once made a point that is a common method used in his field. I think he was trying to show that since used in another field it was OK. Just like use of a term, “trick” in econometrics is OK in climatology. No! It’s not OK, because the use was totally different. “hide the decline” is not a methodology.
    Finally, after several years, Dr. Roy Spencer has had his paper on cloud sensitivity published. It’s importance is that it shows an opposite impact (negative versus positive sensitivity) as that of the traditional climate community and models. An article from the author can be found here: http://www.drroyspencer.com/2010/08/our-jgr-paper-on-feedbacks-is-published/ .

  68. Bryce

    2slugbaits, I agree with you concerning the many deficiencies of the Bush presidency.
    On the other hand, we pay an awful lot of tax right now, much of it going down a rathole, much of it actually harmfully spent. A carbon tax geared to reducing emissions should at least be balanced by other tax reductions.

  69. 2slugbaits

    Bryce “A carbon tax geared to reducing emissions should at least be balanced by other tax reductions.”
    Yes. And that’s exactly what the House version of the cap & trade bill did. The revenues generated were used to offset other taxes. That’s why CBO determined that the tax was not regressive, contrary to what the GOP was claiming.

  70. uber_snotling

    CoRev: Sure, you can have any policy opinion you want. But if you want to argue scientific details, start publishing peer-review articles, not arguing on economics blogs. You are selecting a few articles and ignoring the very wide body of work endorsed by the IPCC and the National Academy of Sciences. If you feel you know how to evaluate the science better than they do, than you are probably wrong.
    As to your point about cost being too expensive, that is the political realm. Your side is winning there.
    tj: I won’t try to convince a skeptic of climate change on a blog response because (1) I’m not a good teacher, (2) this is a crappy medium to do it in, and (3) there are about 1000 web sites that are available that could give you all the info you need and more. If you are a skeptic and unwilling to read the key documents that present the consensus scientific view —http://www.ipcc.ch/publications_and_data/publications_and_data_reports.htm#1 — why would my words convince you?
    Stephen Kopits: Your consensus points are incomplete and misleading. See the IPCC 2007 report for the consensus and certainty regarding climate change.

  71. CoRev

    UberS said: “You are selecting a few articles and ignoring the very wide body of work endorsed by the IPCC and the National Academy of Sciences. If you feel you know how to evaluate the science better than they do, than you are probably wrong.”
    If the theory is falsifiable, then it only takes one report. Consensus and volume have no scientific meaning. Then if the theory is NOT falsifiable then it is truly not science just opinion. Moreover, your appeal to authority (the very wide body of work endorsed by the IPCC and the National Academy of Sciences.) is also not convincing.
    UberS, my journey started on the fence leaning just slightly skeptical. As I studied, I learned just how poor the science was. Hockey sticks that aren’t. Temp records that are so polluted that calculating an average takes repetitive corrections. Models that are so poor it takes ensemble averages to get anything close to a meaningful average temp. IPCC reports that are based upon non-scientific advocacy articles. And, more is discovered every week.
    That knowledge drove me over the edge to full skepticism. In the past year we’ve had climategate, the multiple AR4-gates, and we are finally seeing some contrary scientific studies being accepted and printed. Now, full cynicism has set in. Your science is proving to be a lie. That lie is being recognized by more an more of the world’s populace.

  72. aaron

    The trick was hiding the fact that real temp diverged with proxies, showing that they would have missed large warming events in the past.

  73. GregL

    CoRev said: “Models that are so poor, that their use is via averaging an ensemble of results.”
    Complex systems are:
    1) impossible to model down to the smallest detail because the computing requirements are so immense. For example, climate models have to model the entire surface of the Earth and it’s reaction and interaction with climate forcings. We are talking about relief, vegetative cover, human modifications, cloud formation, snow cover, etc. So models create grids (5 degrees on a side usually) and input a single value for each characteristic. This means that the models display average behavior. And the actual behavior fluctuates about that mean on every grid variable in the model.
    2) Complex systems are sensitive to starting conditions (again fluctuating about all those averages values for each grid square). Since we can’t exactly measure the starting conditions, the model output varies by some statistical distribution.
    Thus the limits of instrumentation and computation means that any SINGLE run of the model will vary from the expected mean output of MULTIPLE runs. Therefore the mean of multiple runs are reported. Thus reporting the mean strengthens the results reported. The law of large numbers tells us that we will converge on the desired result by running the models many times.
    Trying to spin things the way you have is either the result of a lack of understanding or something darker.

  74. CoRev

    GregL, you imply that there is insufficient computing power, that the models are so complex that they need to be run multiple times to get reasonable results, that it takes an ensemble of models of many runs to get to a number that is reasonable, and the only way to reach a reasonable conclusion is to “The law of large numbers tells us that we will converge on the desired result by running the models many times.”. Is that about it?
    What you just said is that we really do not understand climate. With that I agree!
    Let me remind you. I agree that there is GW. I agree that there is AGW. I agree that weather can cause catastrophic results. I am cynical about the ever increasing catastrophic predictions from climate. I am in total disbelief, that CO2 is responsible for those catastrophes.
    If you believe that a 100% reduction in ACO2 will effect average temps by more than a fraction of a degree C in the next century, then you are: “Trying to spin things the way you have is either the result of a lack of understanding or something darker.”
    Folks, at least do the math. Here’s a video starting point: http://noconsensus.wordpress.com/2010/08/29/3446/#comment-35419
    Devastating the West’s economies for a fraction of a degree C is a long way from science and totally a political statement. Admit that and we can have a discussion over any of my above points. At least UberS is partially understanding of the politics.

  75. GregL

    CoRev said: “What you just said is that we really do not understand climate.”
    That is obviously NOT what I said, but I an not surprised that you are attempting to distort my message.
    I surmise that the reason you say thing the way you do is due to darker motives.

  76. CoRev

    GregL, why do you think I am distorting your message? I just interpreted/translated/analyzed you models comment. If you can not address the issues I presented, then why resort to pettiness?
    I am especially interested in anyone’s, especially Menzie’s, analysis of the CO2/temperature mathematics.

  77. a

    “Surely the argument worth having is whether a world of 9.5 billion people can do anything useful collectively about global warming? ”
    A shame that nobody peer-reviewed this statement, huh? I mean, here you have somebody blatantly inflating a critical number by about 50%-ish in order to support a warmist agenda, and everybody else who shared that agenda just smiled, nodded, and didn’t correct their own side.
    This happens with warmists all the time. Because it’s politically useful to have people screaming about how we’re all going to have to move to the Maldives.
    God save me from fundamentalist Gaians.

  78. Barkley Rosser

    CoRev,
    The big fuss over Mann’s work, now the subject of an absolutely idiotic, money-wasting assault on academic freedom lawsuit by VA AG, Cuccinelli against U.VA in an attempt to somehow further “catch” Mann in some embarrassing statement, or, gosh, maybe even an admission that there is now AGW, is all over the “hockey stick.”
    Well, the part that is in controversy is not the recent finding of a rapid rise in temperature unprecedented in speed over any observable period, it is about what the global temperature was 1,000 years ago, which indeed we do not have enough data to know, although we know it was pretty warm in Greenland back then, if not in some other places. But, it does not matter what it was 1,000 years ago. This is just a non-issue sideshow. All of you getting all worked up over that have no idea what you are talking about and that this is just not important at all.

  79. Dean

    We’ve been cutting down trees forever, and burning fossil fuels since the 1830s. It doesn’t seem logical that you could dump stuff into the air for 180 years and expect no effects.
    I’m not a scientist, but let me throw some common sense on the subject.

  80. CoRev

    BR, the VA legal case against Mann is about potential fraud and not science. Mann’s science is now under the microscope because it has been shown to be poor, but his VA tenure will be about what funding he received from the state and how it was spent. I suspect we’ll hear more about paperwork than science, if we actually get to a trial.
    As far as unprecedented warming, without Mann the claim wasn’t even possible. His research removed the MWP and LIA from the records. Removing the MWP made the warming ?unprecedented?.
    But, the real question is what’s magic about the past 1,000 years? That period doesn’t even cover the major glaciation climate cycles. Interglacials appear to have been warmer in several of the cycles. We can also go much farther back and show warmer periods, so what is unprecedented about our current warming?
    CAGW, AGW, GW and even CC are not about science but more about politics. Climate Science is about the science, until we get to a catastrophic prediction, then we may find the prediction stepped over the political line.

  81. Menzie Chinn

    CoRev: Still waiting on the response to comments on Fuller. Anyway, did you really mean to say:

    If the theory is falsifiable, then it only takes one report. Consensus and volume have no scientific meaning.

    Have you ever run an experiment, like, in high school chemistry class? Do you know what “measurement error” is. Have you ever taken a course in classical statistics?

    For what it’s worth, I’ll let Jim Stock take a stab at the analysis (in the paper that Steve Bannister referenced:
    Kaufmann, Robert, Heikki Kauppi, and James Stock. 2006. Emissions, Concentrations, & Temperature: A Time Series Analysis. Climatic Change 77(3): 249-278. Available at: http://dx.doi.org/10.1007/s10584-006-9062-1

    I also think you should read this paper: http://www.springerlink.com/content/vl6g4g28v8215004/

    If you don’t trust Jim Stock’s credentials as a statistician, well, I give up.

  82. uber_snotling

    CoRev: The science is proving to be a lie? You are claiming that now only is climate change wrong, but that the whole enterprise has been based on malevolent scientists intent on deceiving the populace?
    Can you tell me what you are basing your opinion that the IPCC 2007 report is not convincing on? What specific scientific areas did you find to be most troublesome?

  83. 2slugbaits

    CoRev Devastating the West’s economies for a fraction of a degree C is a long way from science and totally a political statement.
    Wow! Noted economist CoRev tells us that cap & trade will devastate…yep, devastate the West’s economies. Would it be asking too much if you’d provide some kind of reference for this rather strong claim? Did you get that one from the Glenn Beck rally? Most economic models that I’m aware of put the welffare cost of cap & trade at something like 2% of GDP. Not trivial, but not exactly devastating either.

  84. 2slugbaits

    Barkley Rosser is right…the “Hockey Stick” debate is largely irrelevant and the M&M conclusions have been largely overturned due to some mistakes in their calculations. They inappropriately used interannual error statistics and tried to apply those to five decade intervals. It’s like trying to calibrate your decade over decade forecast error by extrapolating from hourly forecast errors. It’s far from certain that there even was a global MWP or LIA. We can agree that Europe and North America were probably quite warm 1,000 years ago; but we have very good records from China during that period and China was definitely very cool. So the idea that the MWP was “global” is silly on the face of it.
    Yes, there have been plenty of periods in earth’s history in which temperatures have been more extreme, but the fossil record isn’t too encouraging in that regard, so a little bit of discomfort is probably justified. No one doubts that there are natural cycles that lead to climate change, but those typically take thousands of years. We’re looking at a much more compressed timeframe and that makes any natural explanation kind of implausible. And the causality seems to be reversed. In the past CO2 emissions tended to lag temperature increase; today it’s temperatures that are lagging CO2 emissions. Hard to explain that phenomenon by appealing to natural cycles.

  85. CoRev

    UberS, here’s a list of 94 “gates”, most of which are from your 2007 report. Here: http://www.sodahead.com/united-states/climate-scandals-list-of-94-climate-gates/blog-395039/
    Some of the larger gates are “Kilimanjaro-gate”, “Himalayan Glacier-gate”, and “Amazon Forest/Drought-gate” and my favorite “Yamal-gate”, otherwise known as the magical tree. There are many more. Some of the science references in the report, weren’t science.
    Menzie, you’re going to wait a long time for a Fuller defense. I am not going to replicate Fuller’s research to answer general questions. If you care to pick a point then we can discuss it, but your request is just too general.
    Furthermore, I did mean make the comment re: falsifiability of the AGW theory. As to your other two questions: Yes and Yes! BTW, I am waiting for your response on the request to do the math re: reducing CO2 and the possible temp decrease.
    2slugs, Obama said: (paraphrased) “My plan will necessarily make electricity prices skyrocket.” Maybe CoRev, the economist, thinks that skyrocketing electricity will devastate our economy. Of course, we need to remember the context. Proposing a C&T which makes energy costs skyrocket while in a record setting recession would actually help the economy. Right?
    All we need to do is look at the EU and see how their ETS has worked. In the end it has no effect on temps, and their ETS is rife with fraud and abuse.

  86. CoRev

    Manzie, I’ve not been able to Adobe to read the down loaded paper you referenced. I did find this comment by R. Kauffman on RealClimate here: http://www.realclimate.org/index.php/archives/2005/12/naturally-trendy/#comment-6620
    He said: “Using two separate statistical techniques, I have been able to show (along with David I Stern, James H. Stock, and Heikki Kauppi) that the stochastic trends in the radiative forcing of greenhouse gases and sulfur emissions can explain much of the general increase in temperature over the last 130 years.”
    Initial questions that come to mind are: Two gases are the warming culprit? Not H2O? Not methane? No reference to natural causation for warming? Maybe their paper answers all these questions and the many others, but, frankly, from that comment, it smacks of dabbling with crappy data to support their pet theory. Dunno, still not very convincing, since I have seen little support for their theory since the paper was published.

  87. Menzie Chinn

    CoRev: Just respond to (1) the fact that no confidential information was used, so there were no ethical violations, and (2) the fact that Fuller misquoted Weart, insofar as the word “rubbish” is concerned. No analysis required, just acceptance and recognition of facts.

  88. 2slugbaits

    CoRev The relevant bill is something like the House cap & trade bill. That’s the one that has been modeled and studied by CBO as well as academics. Calling cap & trade “devastating” is whacko. A 2 percent welfare cost is not devastating. Stick with facts. And speaking of facts, no one is talking about cap & trade being implemented during a recession. And even if it was, the tax increase is entirely recycled so there is no contractionary effect. Essentially it acts as a balanced budget multiplier. If you don’t know what that is, go look it up.
    All we need to do is look at the EU and see how their ETS has worked. In the end it has no effect on temps,
    Hmmmm…and here I thought you were telling us that temperatures increases were leveling off. Now you’re saying that temperature increases are continuing unabated by the EU’s approach. Look, we know that cap & trade approaches work because they’ve been used in the past. That’s how the US reduced sulfur dioxide levels.

  89. CoRev

    2slugs said: “And the causality seems to be reversed. In the past CO2 emissions tended to lag temperature increase; today it’s temperatures that are lagging CO2 emissions. Hard to explain that phenomenon by appealing to natural cycles.” You do realize you just made a case for NO RELATIONSHIP????
    2slugs also said: “So the idea that the MWP was “global” is silly on the face of it.” But the most recent evidence is that it was evidenced all over the world. So silly or not, there is evidence. Try this article which list many papers: http://sites.google.com/site/globalwarmingquestions/mwp
    There were two big announcements today! The VA judge denied Cucinelli’s request for M Mann’s UVA records.
    Also, the IAC has issued it’s report re: the IPCC reporting process. Essentially it recommends that the Mgmt be replaced. Moreover, looking just below the surface on what caused some of the procedural change recommendations is more telling than the recommendation.
    For instance what charge is this one being proposed to fix? “Lead Authors should explicitly document that a range of scientific viewpoints has been considered, and Coordinating Lead Authors and Review Editors should satisfy themselves that due consideration was given to properly documented alternative views.” (My emphasis) I’ll just wait over here and let you folks think about it.
    A summary of the findings can be found here: http://wattsupwiththat.com/2010/08/30/iac-slams-ipcc-process-suggests-removal-of-top-officials/#more-24162
    BTW, if any one is wondering why I so often reference WUWT, it’s only because it’s the most active. It often gets there first.

  90. CoRev

    Menzie, as far as confidential information, I’ll accept your understanding. As far as the Weart comment, I don’t (nor do you) know from where he got that? So I’ll stay on the fence with that one.

  91. CoRev

    2slugs said: “And speaking of facts, no one is talking about cap & trade being implemented during a recession.” Now!!!!! But, just a few months ago had they been able to get it passed it certainly would have been passed. Then!!!!
    As far a your comments of CBO estimates and impacts of the Cap & Trade Bill, why are we even discussing a bill that is not formulated and close to being passed? Pure conjecture on your part.

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