"... proponents of the AGW hypothesis cite this supposed “97% consensus” as fact.
... The story behind the origin of this statement demonstrates how readily people accept as fact something they either want to believe is true or feel they don’t have the background to question.
... Shockingly, its unscientific origins are found in a 2013 article put forward by a former Australian cartoonist and web developer who subsequently obtained a PhD in the “cognitive science of climate denial.”
I did not know such a degree existed.
... Cook’s article documented his survey of some 11,944 climate abstracts from 1991 to 2011 matching the topics “global climate change” or “global warming.”
... What this survey found was that 66.4% of the 11,944 abstracts in fact expressed no position whatsoever on man-made global warming.
Of the remaining 33.6% that did express a position on global warming, Cook found that 97.1% of these endorsed the hypothesis that global warming is the result of human activity.
When I first read the Abstract of Cook’s article, I thought that I had misread his conclusions — they made no sense.
Clearly, the survey results showed that the great majority of the 11,944 research papers on topics involving “global climate change” or “global warming” — fully 66.4% of these papers — expressed “no position” on the question of whether global warming could be the result of human activity.
If this was “settled science,” how could so many scientist-authors fail to take a position one way or another on arguably the most important and urgent question in the history of climate science?
In calculating this supposed 97% scientific consensus on the “fact” of man-made global warming, Cook disregarded the 66.4% of the research papers he surveyed that expressed “no position” on that question.
If these papers are properly taken into account, the percentage of scientist-authors who support the hypothesis of man-made global warming (based upon Cook’s survey) is actually 32.6% — hardly a “consensus”!
... the level of intellectual dishonesty in the calculations is breathtaking.
... On May 16, 2013, one day after the Cook publication, President Obama tweeted: “Ninety-seven percent of scientists agree: #climate change is real, man-made and dangerous.”
President Obama thus added a conclusion that even Cook did not reach.
... With Obama’s presidential endorsement, Cook’s statement has been cited ever since as an established “fact”, used to mislead unquestioning people about man-made global warming, and to shame those who do dare to question the hypothesis."
The dishonesty is actually worse than described in the quotes you just read from the article found at the link above.
So let me add some more details about Cook et al., 2013:
John Cook, an Australia-based blogger, claimed 97% of those authors who stated a position, explicitly or implicitly, suggested human activity is responsible for some warming.
His exercise in abstract-counting (not actually reading the scientific papers)
doesn’t support the IPCC claim that climate change is both man-made and dangerous.
It doesn’t even support the IPCC’s claim that the majority of global warming
in the 20th century was man-made.
The Cook study was quickly debunked by Legates et al. (2013) in a paper published in Science & Education.
Legates et al. found
Most of the papers are not about climate change, and its causes, but were taken as evidence anyway.
Papers on carbon taxes, for example, assume that carbon dioxide
emissions cause global warming – but merely using that assumption does not mean the paper supports the claim that climate change is both man-made and dangerous.
Papers on the effects of higher CO2 levels on plant growth, assume a continuing rise of atmospheric CO2, but merely using that assumption does not mean the paper supports the claim that climate change is both man-made and dangerous.