One of the leading talking points of the climateers, repeated more often than the rosary in the Vatican, is the factoid that “97 percent of scientists agree” that human-caused climate change is real. As I’ve noted before, the only surprise is that the number isn’t 99.5 percent, as the question of whether greenhouse gases have a warming effect—all other factors being equal—is uncontroversial.*
Of course, all other factors are not equal, which is why IPCC climate science reports are thousands of pages, and why the number of scientists down with the extreme or catastrophic forecasts is much lower. But it turns out if you peel back the original survey behind the “97 percent” claim, you find that the methodology is just as dodgy as the climate models that said we should be about 0.4 degrees warmer than we are by now.
Lord Monckton of Brenchley is all over the case, demanding that Environmental Research Letters retract the article where the 97 percent claim is made. It’s a long post, but here’s the clinching argument:
I am disappointed – and so should you be –
- that the paper had erroneously and gravely over-claimed 97.1% “scientific consensus;
- that the authors had tried to conceal that they had had categorized only 64 abstracts out of 11,944 as explicitly endorsing the “scientific consensus” as they had defined it;
- that, even then, the authors had miscategorised 23 of the 64 abstracts as endorsing that “scientific consensus” when the 23 had not in fact endorsed it;
- that the authors had failed to disclose that their effective sample size was not 11,944 nor even 4014 papers but just 119, rendering the entire exercise meaningless;
- that, on the basis that one of the authors now says was intended, that author says they had meant 87% consensus (not 97%) among just 73 abstracts (not 4014);
- that the true “scientific consensus”, after correcting an obvious error in the newly-asserted (and still strange) basis for calculation, would be 34% of just 119 abstracts;
- that the authors had failed to admit that only 1% of the 4014 abstracts they marked as expressing an opinion had endorsed the “scientific consensus” as they had defined it;
- that the authors had failed to disclose that only 0.3% of all 11,944 abstracts had endorsed that “scientific consensus”;
- that the authors had not adhered to a single definition of “scientific consensus”; and
- that one of the authors, in a public scientific forum, continues in defiance of the truth to assert that 97.1% had “said that recent warming is mostly man made”, when very nearly all of the abstracts had neither stated nor implied any such thing.
* From the Los Angeles Times story on the IPCC’s problems, citing GIT scientist Judith Curry: “All other things being equal, adding more greenhouse gases to the atmosphere will have a warming effect on the planet,” Curry said. “However, all things are never equal, and what we are seeing is natural climate variability dominating over human impact.”