Many debates about global warming seem to boil down to appeals to authority, with one side or the other citing some famous scientist, or group of them, to buttress a particular argument. The tone is often, ‘My expert is better than yours!’

Against this backdrop, some analysts have been trying for several years to get a firm handle on where climate researchers come down, as a group, on the central issues in the global-warming debate: Is the earth warming up, and if so, are humans largely responsible?

Now comes another entry in this developing literature. William R.L. Anderegg, a doctoral candidate at Stanford University, and his fellow authors compiled a database of 1,372 climate researchers. They then focused on scientists who had published at least 20 papers on climate, as a way to concentrate on those most active in the field. That produced a list of 908 researchers whose work was subjected to close scrutiny.

The authors then classified those researchers as convinced or unconvinced by the evidence for human-induced climate change, based on such factors as whether they have signed public statements endorsing or dissenting from the big United Nations reports raising alarm about the issue. Then the authors analyzed how often […]