Consensus collapse
Jun 5, 2014
Bishop Hill in Climate: Sceptics, Climate: Tol

Most people who have looked at John Cook's legendary 97% consensus paper would say it is little more than a legend, but the study's continued citation in the popular press does leave a pressing need for a thorough refutation, which has now helpfully been provided by Richard Tol. The paper is paywalled here and there is a useful presentation of the results here, which is more accessible to the layman.

Overall, Cook did not show what he claimed to show. He merely demonstrated his incompetence in survey design and statistical analysis. The secrecy around the data suggests that there are more problems.

Climate policy is for the long haul. We need a broad consensus, maintained over decades, to decarbonize the economy. We need sober, non-partisan research. We need open discussion about the pros and cons of all options for climate policy. Instead, Cook and friends tried to shut down the debate, but their incompetence and secrecy only served as fuel on the flames of an already polarized debate.

This has prompted a remarkable rapid response from an anonymous author here, which says that Tol has it all wrong. If I understand it correctly, Tol has corrected Cook's results. The critic claims to have worked back from Tol's results to what should have been Cook's original results and got a nonsense result, thus demonstrating that Tol's method is nonsense.

Tol's reply today equally quickfire and says that his critic, who he has dubbed "Junior" has not used the correct data at all.

Junior did not reconstruct the [matrix] T that I used. This is unfortunate as my T is online...

Junior thus made an error and blamed it on me.

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