Getting it right

Re: “Herd mentality,” Letter, Dec. 27.

Michelle Stirling makes many false claims about the paper on consensus written by John Cook and several co-authors, including me. Contrary to Stirling’s assertions, we did not scan “only the abstracts of various papers,” but we also conducted a survey of the papers’ authors to evaluate the entire contents of their own papers.

In both cases, among those who expressed an opinion, about 97 per cent endorsed the consensus that humans were a major driver of recent climate change and only three per cent expressed a contrary opinion. These results are consistent with previous studies.

It is true that many papers do not address the question of the attribution of climate change, especially in the limited space available in an abstract. However, you would see the same kind of thing in many other fields. It is rare for biology papers to contain an endorsement of natural selection and few scientific articles in petroleum geology endorse the biotic origin of oil. These scientific theories are taken for granted, dissenters are scarce and the supposed scientific controversy in these fields is generally ignored by mainstream scientists.

Our paper did not claim “proof of global warming.” Our measurement of the degree of consensus in climate science was descriptive, not prescriptive. Climate scientists do not agree about everything and many is- sues are not settled. However, the overwhelming majority accept that humans have played a major role in influencing the climate of the modern era; the interesting problems lie elsewhere.

Few political leaders in Canada reject the consensus opinion of the experts on climate change. Rejection of the overwhelming opinion of experts has become a fringe position.