It's about time to review the evidence for man-made global warming

Some people seem to think man-made global warming has been proven.  Others believe there's no evidence that man-made warming exists.  Neither is correct.  Evidence exists, but, as people familiar with courts of law will know, what's submitted as evidence is not automatically proof.

Firstly, a judge might decide that what is submitted as evidence is inadmissible because it's not evidence at all (e.g., irrelevant, opinion, hearsay, obtained by unacceptable methods) or of negligible value.  Secondly, lawyers for the two parties ask questions that test the credibility of the evidence, and the witnesses are compelled to answer those questions.  Finally, it's up to the jury to decide if the evidence is conclusive.

None of this happens with scientific "evidence."

Chapter 1 of the IPCC's 2013 climate assessment report describes evidence as "data, mechanistic understanding, theory, models, expert judgment."

Regarding the IPCC's claims of man-made warming, I don't think these amount to much at all.  Many of the data are uncertain, the "mechanistic understanding" says only what might be happening, and the theory might not be true in the real world.  Models are not evidence, especially when they have not been verified, do not accurately include all factors, and are weighted toward the prime "suspect."  Expert judgment is merely opinion, and opinion is usually accepted as evidence only when applied to very specific issues in court cases.

Some people seem to think the IPCC's evidence is conclusive proof.  This would be like the police presenting evidence and then the judge jailing the person, with no court case in between to test the evidence.

Other people seem to think they are capable of evaluating the scientific evidence for man-made warming.  In reality, probably less than 5% of the population has the appropriate education to understand the issues, and even fewer have the interest in exploring climate matters in depth. 

With no examination of the evidence, we don't know the truth of the matter.  It makes no sense to dismiss alternative ideas or to label someone a denier when the truth hasn't been established, but that's what has happened. 

The IPCC can't examine the evidence it gathers because the organization's charter is to report on the human influence on climate and what might be done about it.  It was told to consider just one "suspect," so, naturally, it tries to find evidence to support a case against that suspect.

Science as a whole has shown itself to be incapable of resolving disputes.  It has no forum in which the evidence can be questioned and evaluated, no forum that demands responses to questions and challenges.  Some scientific disputes have dragged on for years without resolution.

It's true that scientific truths are provisional in case new evidence overthrows an old theory, but that shouldn't stop the open, impartial, and detailed examination of evidence so as to clarify what is known with reasonable certainty, what's speculation, and what flaws exist in a scientific claim.

When companies want to commercialize scientific findings, the first thing they'll do is verify that the claims stack up.  To do that, they examine both the methods used and the evidence supporting the findings.

When governments' policies are based on science, then it's up to the governments to first determine if the science is solid.  It would simply be irresponsible of any government not to do so.

Testing the evidence requires an open, impartial, and objective evaluation.  The process cannot be political, because it has to recognize an essential difference between politics and science.  Politics is settled by consensus (i.e., votes), but science is interested only in how well certain ideas (i.e.,  hypotheses) account for what's been observed and how those ideas relate to accepted science.  Science also has a "null hypothesis" that argues that an apparent causal link between two factors might be a coincidence or might be driven by some other factor.

President Trump's proposal for a review of climate science looks like the kind of evaluation that's needed.  For far too long, warmists have avoided close scrutiny of their claims.

Let's just hope that it's like any court case, with witnesses cross-examined in regard to statements they've made, compelled to answer questions, and maybe even subpoenaed to attend.

It would be ridiculous to put more effort into testing evidence in court for a minor crime than testing scientific evidence that threatens to put a large financial burden on the U.S. and much of the world.

Usually, when people believe their evidence to be compelling, they can't wait to get to court and show the truth of their claims.  The warmists tell us that their evidence is compelling, but they seem curiously reluctant to try to prove it in a formal inquiry.  Maybe their argument is far weaker than they've been claiming.  If that's the case, then it's all the more reason for an open, impartial, and objective review.

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