The 97% figure comes primarily from a 2013 study by John Cook and colleagues that reviewed abstracts of nearly 12,000 scientific papers. But the methodology has been widely criticized, even by some of the scientists whose papers were included.

The study categorized papers that acknowledged any human contribution to warming as part of the 'consensus.' This is an extremely low bar — virtually everyone, including most skeptics, agrees that human activity has some warming effect. The actual question is how much, how fast, how dangerous, and what to do about it. On those questions, there is significant scientific disagreement.

When Richard Tol, a climate economist whose work was included in the 97%, reviewed the methodology, he found significant miscategorization. He noted that the study was 'not a survey of the literature' but rather 'a marketing tool.' Geologist David Legates and colleagues re-examined the same papers and found that only about 0.3% explicitly endorsed the claim that humans caused most of the warming since 1950.

The appeal to consensus is itself unscientific. Science doesn't work by vote. Einstein didn't need 97% of physicists to agree with relativity. Plate tectonics, H. pylori causing ulcers, and continental drift were all initially rejected by overwhelming scientific consensus.

What most climate scientists do agree on: the Earth has warmed, CO2 is a greenhouse gas, and humans contribute to warming. What they disagree on: climate sensitivity (how much warming per doubling of CO2), the role of natural variability, the accuracy of models, the severity of future impacts, and optimal policy responses.

I'm for clean energy innovation, nuclear power, and practical emissions reduction. But shutting down debate by claiming 'the science is settled' is anti-scientific. The best policy comes from open inquiry, not enforced consensus.