Is it reasonable to be a global warming skeptic?


When an assertion is disputed, making four more assertions just as disputed does not add to your case. Let me just mention one of them. The “97% myth.” That came from a study by John Cook which has been the target of unfair criticism. One of those criticisms is that 12,000 papers were initially found in the automatic search and 2/3 of those papers were excluded as being irrelevant to the subject of global warming. But that is a necessary consequence of the limitations of the automatic search based only on keywords. Similarly, the study was criticized for counting only the papers that took a position on global warming. The criticism says that we don’t know what position the authors of those papers take. Again when forming a statistical sample, it is entirely appropriate to count only the ones that do take a position.

Public opinion research is done the same way. They attempt to poll a very small percentage of the total population. Among the people they attempted to contact, some did not answer their phone. Some answered, but declined to participate in the survey. The number of people excluded for these reasons are not counted in the final results, and that is OK.

But perhaps the most telling thing about the criticism of the Cook study is that in view of all the effort that went toward making the study objective and precise, not one of the critics have launched their own comparable study. After all these years during which the Cook study has been criticized, if the critics channeled their efforts into a comparable study that concluded that only 20% of scientists agree with global warming theory, they would have a better case than just throwing ineffective stones at the Cook study.

Much of the criticism is directed at the subsequent interpretation of the Cook study, given that the study itself had several levels of agreement. Subsequent interpretation of the Cook study is a separate issue, and criticism of those interpretations may be well-founded. But that should not reflect on the study itself.


I have tried to make a distinction between supporting the global warming theory and supporting policy decisions based on the theory. I think a good argument can be made against the policy decisions on purely practical and moral grounds. You don’t have to discredit the science to do this.

And others are likely to be misled if they consider all opinions on difficult scientific questions to be of equal value. (By the way, I eschew videos produced by scientists too. Not for ideological reasons, but for practical reasons: They are hard to search and read at my own rate. Like most people, I can read faster than people can talk.)

Or we can try one small aspect at time. That’s OK too.


If someone splits hairs too many times, then the entire logic chain disintegrates.


Let us begin at the beginning. This roughly corresponds with Part 1 of the youtube series “CO2 on Trial.”


  1. How I became a skeptic. Here are some of the thought processes I went through, as well as my post hoc rationalizations re the same.

In a representative republic the ultimate deciders on the great public issues such as global warming are individual citizens. We all know that one of the duties of citizenship is informed voting. But how can lay folk hope to become educated on the complex subject of global warming so that we can elect the right leaders on this issue? Are we even capable of adjudicating between the competing scientific claims made about it? The reality is that, educated or capable or not, we determine the outcome, just like jurors in a trial.

As with any juror, we lay folk are entitled to our initial opinions and inevitable biases based on our present knowledge and life experiences. As with any juror, the only other thing we are obliged to bring to the case is a fidelity to the truth, no matter our biases. We do have an epistemic duty to have justified true beliefs, to the extent we are able. Does our epistemic duty require us to trust the experts? Normally there should be a presumption that the experts are right. But that presumption can be overcome.

Getting back to our intuitions based on our life experiences… Living in the USA’s Siberia, as we do, the thought did occur to us that maybe global warming isn’t as bad as it is claimed to be. As NoDaks aware of our state’s history, we also remember that Easterners don’t always have our best interests in mind when they prescribe policies that affect our way of life. So when President Obama proclaimed his war on fossil fuels, our skeptical antennae were up.


Lay folk are already rightly a little suspicious of the reliability of some aspects of science. Consider the ever-changing claims about what we should eat or don’t eat—all based on science!! We also know that cheating is not unheard of in science. And we noticed that some pretty smart people were openly skeptical. Take for example, Michael Crichton. There were lots of indications that the field of climate science was very politicized. Lay folks who doubted were called deniers and anti-science. And look who the Global Warming Movement made their poster-boy! Al Gore winning the Nobel clinched it. Something definitely didn’t smell right about this whole global warming business. And further fueling our skepticism was the awareness that our way of life was being threatened by the war on fossil fuels. Gee, given all this, didn’t the whole global warming issue warrant some second thoughts? [By this time human CO2 emissions were already convicted of causing dangerous global warming and the only “reasonable debate” was how best to reduce our emissions.]

So we were well past feeling helpless and hopelessly dependent on the experts. But how to proceed? Begin by reading widely. Start with the popular “dumbed down” literature and consuming other media which serve as points of entry into the subject at hand. But what about the danger of becoming misled by charlatans and conspiracy theorists and the like? Along the way, we picked up Aaron Wildavsky’s book, But Is It True?, which explains how to achieve a well-rounded education on a subject and come to your own conclusions.

But in the end, however “eddicated” we become, we still are lay folk. Vast territories of the subject remain impenetrable. But at least we know the general landscape. And while we, of ourselves, have no ability to judge whether Michael Mann did his sums correctly, we can note that two expert review panels, one friendly to him and one more objective, came to the same negative conclusion. From that we can reasonably conclude that Mann’s Hockey Stick is bunk.


We can also employ the tools available to all juries in coming to reasonable conclusions. For example, if someone is caught lying or at least giving inconsistent statements, we are entitled to not believe him. For example, Michael Mann claimed in his paper that he performed the verification statistic R2. He later told a Dutch journalist that his temperature reconstruction passed that test. He later told an expert review panel that he didn’t perform that test and that it would stupid to have done so. McIntyre convincingly demonstrated that Mann’s reconstruction flunked the R2 test. From this we can reasonably conclude that Mann’s character for telling the truth is lacking. We are therefore justified in believing that Mann’s reconstruction flunked the test. We are also justified in discounting any of his other testimony.

I could go on in a similar vein, but the point I want to make is that lay folk are capable of coming to reasonable and informed judgments about the science of global warming.


Well, there are also cosmic rays.

You know, once upon a time, if you mentioned cosmic rays, then people would give you the little circle wrist against the temple motion.

Now, after CERN’s work, cosmic rays have more respect.

AND, there is no way you can find cosmic rays in a greenhouse … [unless it leaks in] … it’s not part of “greenhouse gases”.


Hi Monte,

Yes, and as we know from Solomon’s book The Deniers, the sun/cosmic ray connection to climate was neglected by the IPCC from the get go. Folks should also read Vahrenholt and Luening’s book The Neglected Sun.

So, how did you become one of them “deniers”?


I think you have inflated the importance of Michael Mann in the climate debate. He may have been a very public face of the theory. And any single individual can be found lacking in personal or scientific character and ethics. But global warming is not his baby alone. What about Peter A. Stott, Gilbert Plass, Jerry D. Mahlman, Kevin Anderson, Katharine Hayhoe, and let’s not forget Thomas Sterry Hunt who in 1863 became the first American scientist to link CO2 with climate change. I guess Michael Mann built a time machine and traveled back to 1863 to corrupt Hunt as part of his master plan. How he got to those other scientists is yet to be discovered, but I’ll bet Breitbart is working on it.


If it was Mann alone who acted unethically then not much could be made of the incident, but he was not by any means alone, and inasmuch as his graph was the poster child for the IPCC report (R3? R4?) these shenanigans take on a more significant tone. It is certainly fair to ask why, if the “science is settled” as is claimed, and “97% of scientists” believe in AGW, then why did so many people go to such lengths to fabricate data to make the point?

Everyone knows that CO2 contributes to atmospheric warming. What no one really knows is what happens when the concentration increases, and if they don’t know that now it’s pretty certain much not much was known about it in 1863.


Always been a durn “denier”. BECAUSE, it’s ALL about the data.

Data, data, data.

Always, always, always visit the field.

See for ones-self.

Data, data, data.


Once upon a time, I got into a “fistfight” with the science editor of a MAJOR metropolitan newspaper because I discussed “sunspots”.

I “believe” in sunspots.

The science editor did not.


I dispute your characterizations of shenanigans, fabricate (when applied to “so many people”). More later on “the science is settled.”

Everyone knows that CO2 contributes to atmospheric warming. What no one really knows is what happens when the concentration increases, and if they don’t know that now it’s pretty certain much not much was known about it in 1863.

You and Theo have made the point about “everyone knows CO2…” and then downplaying what “everyone knows” to bring it down to a level you find acceptable. Similarly, you up-play the claim about “the science is settled” to make it look like people are claiming more than they really are. Sure, some people say these words, but they do not reflect the scientific reality. Of course the science is not settled. It never is. Recent academic articles show that scientists have been and are continuing to refine climate change. Debate over extents of this and causes of that are robust in the literature. There is no conspiracy of forced uniformity. See, I can play that game too. I take a proposition you want to promote, and then agree with it, and then, after agreeing with it, modify it to suit my position.


In my intro I was just using him to illustrate the point that a layman can reasonably discount the scientific work of an individual scientist based on his history of not telling the truth. We can get into his role in the whole debate later.


To dispute global warming theory you have to discount the scientific work of more than one individual scientist. That is why I asked what you have on the others? Because you are not just rejected the work of Michael Mann when you reject global warming.


Be patient. I’m just getting started.

  1. If there was a trial…

If there was a trial, who were the participants? What were the charges?

Venue: The UN

Defendants: CO2, a completely natural substance comprised of one atom of carbon and two atoms of oxygen. It is an odorless and colorless trace gas which makes up 4% of 1% of the atmosphere. It is essential for life on earth. Also included as defendants were everyone who produced or burned fossil fuels, the burning of which emits CO2 into the atmosphere.

Prosecution: A diverse social movement comprised of environmental groups, politicians, population control advocates, rent-seeking corporations, anti-capitalist groups, and others who want to blame human CO2 emissions for causing dangerous global warming. Al Gore can serve as the face of the prosecution.

Defense: Various dissident scientists and journalists. Citizen scientists such as Stephen McIntyre have played an important role.

The complaint: Human CO2 emissions are causing dangerous global warming.

Judge/Jury: The UN’s International Panel on Climate Change played both roles, judge and trier of fact.

Key Witnesses: The IPCC also served as the prosecution’s leading expert witness. Computer models also were important witnesses.

The Gallery: Science journalists, mostly, who were all in for the prosecution.

Where we are at in the trial: CO2 has been found guilty. The prosecution’s primary witness, the IPCC, recommends drastic and sustained cuts in human CO2 emissions. Various measures to carry out the sentence have been implemented and others are being debated.

But!, the majority of the public rank global warming very low on its list of concerns. Some, such as yours truly, argue the whole case should be reopened because of substantial evidence of prosecutorial and judicial misconduct and new evidence which exonerates CO2.

  1. The Prosecution’s Burden of Proof

Now a few words about the prosecution’s burden of proof, or at least what should have been its burden of proof. Being now in the sentencing phase of the trial, the prosecution has been arguing for the drastic reduction of CO2 emissions by various means. But what must be true before a rational society adopts any of these measures. Actually quite a lot, as we shall soon see.

Elements of the Case:

  1. The Earth is warming unusually.
  2. Rising atmospheric CO2 is the main cause of this warming.
  3. Human CO2 emissions are the main cause of the rise in CO2.
  4. The warming cause by human CO2 emissions will be dangerous.

The prosecution has to prove each element before CO2 can be found guilty. None should be assumed. If any one of them lacks a sufficient scientific basis established by some reasonable standard, then the entire case against CO2 collapses.


Sufficiently proving 1-4 then sets up the conclusion that something ought to be done about it. And so we have arrived at the public policy part of the case, which has its own proof elements. Shocking as it may be to Vice President Gore and his followers, even if the first four elements been sufficiently proved, it does not automatically follow that we should drastically curtail our CO2 emissions by any means. The prosecution first has to demonstrate the following: First, it must be true that the GW problem is so pressing that it be given priority over other global problems such as fighting poverty, world hunger and disease-- problems which affect us right now, not 50 years from now. In this regard, I refer you to the work of Bjorn Lomborg and the Copenhagen Consensus. Second, it must be true that any proposed mitigating measure will be effective in reducing global warming. If the proposed remedy for the climate crisis won’t do any good, then what’s the point? In this regard, I point out that the EPA’s proposed regulations for coal-fired plants are projected to have little or no effect on the climate, something which even the EPA admits. Third, it must be true that we have identified the costs of cutting CO2. This not only includes the direct costs of implementing any given solution, but also negative unintended consequences. Take, for example, the drive for so-called sustainable fuels. It has helped create a situation in the US where we put over 40% of corn crop into our gas tanks, a misallocation of resources which has serious implications for the world’s food supply. Global warming policies are not necessarily benign, and any rational policy analysis will recognize that fact. The costs of global warming mitigation also should include the benefits of a warmer climate not realized by pursuing mitigating measures. Finally, the benefits must outweigh the costs.

So we see that many things have to be true before it is rational to drastically cut CO2, and Mr. Gore and his allies will just to patient as we do our post mortem on the trial.

Scientific Elements
  1. The Earth is warming unusually.
  2. Rising atmospheric CO2 is the main cause of this warming.
  3. Human CO2 emissions are the main cause of the rise in CO2.
  4. The warming cause by human CO2 emissions will be dangerous.

Policy Elements
5. GW problem is so pressing that it be given priority over other global problems.
6. Drastically reducing CO2 emissions from fossil fuels will be effective in reducing global warming.
7. We have reasonably identified the costs of cutting CO2 including the benefits of a warmer climate not realized by pursuing mitigating measures.
8. Benefits of drastically reducing fossil fuel use outweigh the costs.


We also must address what standard of proof is appropriate. Policy debates either ignore or are very vague on this question. In legal cases the standards range from “a mere scintilla of evidence” to “beyond a reasonable doubt.”

We will adopt the preponderance of evidence standard-- the so-called 51% standard. In other words, we will consider an element proved if we find it more likely than not to be true. Another way to define a preponderance is if we find that the greater weight or amount of evidence supports the conclusion.

We also should note that the prosecution all along has argued for the application of the precautionary principle. The precautionary principle holds that we should lower the standard of proof if an action or policy has a suspected risk of causing harm to the public or to the environment, even in the absence of scientific consensus that the action or policy is not harmful. In other words, “better safe than sorry.” In addition, the principle would put the burden of proof on CO2 to show it is not guilty.

We reject the precautionary principle. First, the precautionary principle is ambiguous and has no agreed-upon definition or criteria. In addition, it is irrational. We also observe that its ambiguity makes it arbitrary in its application and particularly susceptible to political pressures rather than scientific analysis.

So we will be unswayed by appeals to the precautionary principle. The prosecution has the burden of proof and must meet it.

Now that our citizen’s investigation has some focus, let’s see begin evaluating the case against CO2.

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