The “survey” was a two-question, online questionnaire sent to 10,257 earth scientists, of whom 3,146 responded.
Of the responding scientists, 96.2 per cent came from North America.
Only 6.2 per cent came from Canada. So the United States is overrepresented even within that North American sample.
Nine per cent of US respondents are from California. So California is overrepresented within not just the US sample: it has over twice as large a share of the sample as Europe, Asia, Australia, the Pacific, Latin America and Africa combined.
Of the ten per cent of non-US respondents, Canada has 62 per cent.
Not content with such a distorted sample, the researchers then selected 79 of their sample and declared them “experts.”
Of those 79 scientists, two were excluded from a second supplementary question. So 75 out of 77 made it through to the final round, and 97.4 per cent were found to agree with “the consensus”. That’s where the 97 per cent comes from.
So this is a very Michael Mann “reconstruction”: just as a couple of Californian bristlecones can determine the climate for a millennium, so a couple of dozen Californian scientists can determine the consensus of the world.