I always hear the alleged statistic that 97% of scientists believe in man made global warming– which is now “climate change” because the experts couldn’t predict the temperature trends, the financial crisis, Hillary’s defeat…. Anyways, I am summarizing the problems with that statistic for my own future reference, and for yours. You’re welcome.
I will quote from John Kerry, as he summarizes the claim succinctly: “97 percent of climate scientists have confirmed that climate change is happening and that human activity is responsible… they agree that, if we continue to go down the same path that we are going down today, the world as we know if will change– and it will change dramatically for the worse.”
The 97% statistic originally came from a 2013 study led by John Cook.
First of all, as Alex Epstein clearly explains in his book the Moral Case for Fossil Fuels (highly recommended), there is so often a bait and switch going on in discussions regarding the 97%. Regardless of the actual number (which we will get to), Cook’s study said absolutely nothing about going down the current path, the world as we know it changing, and, especially, the world changing for the worse. That’s just typical fear mongering: taking a single statistic and exaggerating and broadening its application for political gain.
Now, here is how Cook got to the 97%. He first surveyed 11,944 abstracts– just the abstracts, not the papers themselves (much less getting a statement from the authors)– from papers that had to do with global warming, based on a simple search for the matched topics “global warming” or “global climate change.”
The results of the abstracts (got this from here):
Then he took categories 1 and 2 (those who had a strong opinion that man is causing global warming) and compared it to categories 6 and 7 (those who had a strong opinion against the claim that man is causing global warming). The ratio here is 986 papers vs. 24; or 97%.
Okay… so does this mean 97% of climate scientists agree?; that is, there is a solid consensus? Sure, if you leave out the fact that there are about 8,000 (!!) without an opinion/uncertain. If you account for them (and why shouldn’t we?), the new percentage comes in closer too… 10%. Hard to get the crowds going with that.
And of course, to be more than fair, if you could also stretch the thesis by looking at the ratio of categories 1-3 compared to those 4-7, which is around 33%. Still, not worth bragging about that’s for sure.
There’s also some other highly relevant bits of information. First, as Neil Frank mentions here, the reason why there were only 24 papers published by those who strongly disagree with the “consensus” (lol) in the first place was because literally thousands of papers were denied entry into the very database of papers that Cook et al were searching! Frank refers both to this book of published emails relating to this academic scandal and one Kenneth Richard who documented many papers over 2014-2016 that “challenge[d] the hypothesis that CO2 has been the primary driver of recent global warming.”
However, you don’t have believe there was a cover up (I do, for the record), to realize that regardless, there were 1000’s of papers that did not enter into Cook’s math at all, all of which were likely in categories 6 and 7.
Thus, it is profoundly unscientific to state “97% of climate scientists agree that….” It is more honest and accurate to say “97% of 1,010 papers, taken from a set of 11,944, which was a politically limited set to begin with, agree or mostly agree with the “consensus.” In which case, “consensus” here is like saying there is a consensus that John Mcafee should be elected President.
Thus, here’s how to respond to Barack Obama’s following Tweet.
— Barack Obama (@BarackObama) May 16, 2013
Besides the above refutation of the 97%, “scientists” is the broadest description of the authors of these papers anyways. Think of all the science professionals who research outside the bounds of climate-related science. The 97% is a completely made up number. And, most importantly, zero percent (ZERO!!!) of the paper abstracts were considered in terms of their “danger” or threat to human life, civilization, or the economy.