File this one under 'Lies, Damn Lies and Statistics'.  I came across this information several years ago.  For those who haven't, well, here you go...

Exposed: The ‘97% of scientists agree with manmade global warming’ lie

ByDavid Craig

OUR government is imposing draconian limitations on our lifestyles, our economy and our finances to save the planet from supposed catastrophic anthropogenic global warming (CAGW), now renamed ‘climate change’.  Probably one of the most repeated arguments you’ll hear in support of the need to achieve ‘net zero’ is that ’97 per cent of scientists agree CAGW is happening’.

President Obama is just one of many who have made this claim: ‘Ninety-seven per cent of scientists agree: climate change is real, man-made and dangerous.’

So did President Biden’s Special Presidential Envoy for Climate, John Kerry, when he warned of the ‘crippling consequences’ of climate change and said: ‘Ninety-seven per cent of the world’s scientists tell us this is urgent.’ 

Yet, in spite of the damaging effects reaching ‘net zero’ will have on Western economies, not a single politician or mainstream journalist seems to have made the effort to find out where this ‘97 per cent’ figure came from and how accurate it is.

The main author of the paper which came up with the figure was John Cook, an Australian former web programmer and blogger who later gained a PhD in philosophy at the University of Western Australia and founded what could be seen as a climate alarmist website.

He assembled a group of volunteers recruited via the website as part of a ‘citizen science’ project and tasked them with examining the abstracts of 11,944 climate papers from 1991-2011 matching the topics ‘global climate change’ or ‘global warming’. Note that the volunteers didn’t speak to any scientists and didn’t read the scientific papers. They just looked at the abstracts – a summary paragraph or two. The volunteers classified the abstracts into one of seven categories according to their opinions of Anthropogenic Global Warming (AGW):

1.      Explicit endorsement of AGW with quantification

2.      Explicit endorsement of AGW without quantification

3.      Implicit endorsement of AGW

4.      No position or Uncertain

5.      Implicit rejection of AGW

6.      Explicit rejection of AGW without quantification

7.      Explicit rejection of AGW with quantification

The reviewers then ‘simplified’ results into four main categories as follows:

Endorse AGW               3,896                   32.6 per cent of abstracts

No AGW position         7,930                   66.4 per cent of abstracts

Reject AGW                  78                         0.7 per cent of abstracts

Uncertain on AGW      40                         0.3 per cent of abstracts

This gave 32.6 per cent of abstracts which the reviewers concluded endorsed AGW.

Now comes the clever bit. Instead of admitting that just 32.6 per cent of papers (actually just abstracts of papers) endorsed AGW, the group removed the 7,930 abstracts which didn’t take a position on AGW. That left just 4,014 abstracts of which 3,896 (97 per cent) supposedly ‘endorsed’ AGW.

This is like doing a survey of the voting intentions of 1,000 people. You find that 90 say they’ll vote Labour, 10 say they’ll vote Conservative and the remaining 900 are undecided. You eliminate the 900 undecideds and claim that 90 per cent of voters support Labour and just 10 per cent of voters will vote Conservative. This is, of course, complete statistical nonsense as the real percentage of the sampled 1,000 voters who have said they will vote Labour is 9 per cent, not 90 per cent.

That’s not the end of the magic employed to reach that wondrous 97 per cent. The reviewers lumped together three categories of abstracts – ‘explicit endorsement with quantification’, ‘explicit endorsement without quantification’ and ‘implicit endorsement’. (Implicit endorsement means that the reviewer felt that the paper endorsed the AGW theory even though the paper didn’t do so explicitly).

In the paper claiming 97 per cent support for AGW, the reviewers don’t tell us how many papers fitted into each of these three categories, but the survey’s own database shows that of the 3,896 abstracts which supposedly ‘endorsed’ AGW, just 64 were in the ‘explicit endorsement with quantification’ category; 922 were in the ‘explicit endorsement without quantification’ and the vast majority – 2,910 out of 3,896 – were in the ‘implicit endorsement of AGW’ category.

Thus only 986 of 11,944 – that’s just 8.2 per cent – of abstracts explicitly said they agreed with the theory of man-made global warming.

To summarise, this ‘97 per cent of scientists’ claim was based on the work of 11 to 12 volunteers, whose scientific credentials have not (as far as I know) been released and all of whom were probably firm AGW believers. Each looked at around 1,000, often quite obscure, scientific abstracts and from these documents decided whether the scientific papers (which they hadn’t read) supported the AGW theory. To claim such an approach is statistically valid is beyond farcical. To call the ‘97 per cent of scientists endorse AGW’ result ‘garbage’ could be seen as insulting to garbage.

Given the damage ‘net zero’ will do to our economies and our lives, it is incredible that not a single politician, mainstream journalist or editor seems to have had the ability or the inclination to expose the dubious origins of the ubiquitous ‘97 per cent of scientists endorse AGW’ claim.

Source: TCW