97% nonsense.

97%

You’ve probably heard the statistic that 97% of climate scientists agree that humans are causing global warming.

Have you asked where that number comes from?  Is it true?  The source is a paper by Cook et al. and, no, it is not true.

First, the 97% stat is the percent of abstracts expressing a position on AGW that implicitly or explicitly endorsed it.  However, 66% of all abstracts reviewed expressed no opinion on AGW.  A recently published review of the Cook paper found “just 0.3 % endorsement of the standard definition of consensus: that most warming since 1950 is anthropogenic.”

Second, the 97% is of abstracts not scientists.  Abstracts are brief summaries of papers.  To really understand a study, you have to read more than just the abstract.  Each abstract can have multiple authors who may or may not agree with every conclusion in the paper so you can’t even just multiply the number of papers by the number of authors.

Relying on published abstracts is also biased. Challenging a popular position means that research is less likely to be funded and papers are less likely to get published.  To know what scientists believe about any topic would require asking them in a systematic, unbiased, anonymous manner.

And even then consensus doesn’t matter.  99.999% of people believing something does not make it true.  For example, physicians used to believe that gastric ulcers were caused by spicy foods and stress until two Australian scientists proved that most are caused by H. pylori bacteria.

TL;DR: No AGW consensus and consensus doesn’t equal fact.

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One thought on “97% nonsense.

  1. I wonder if there are any surveys of climate scientists that would give that number. Here, let me google that for you….. (hint; try searching for climate scientist survey)
    75/77 = 97.4%

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