Particularly look to see if they have calculated the null hypothesis (“P value”. I was linked to a “Scientific American” article for climate change doubters and all they referred to was this scientist that, by hand, calculated a 6 degree change over a century and that their observations say that he was right. They, however, did not say what the chance was that it was either a fluke (measurement problem) or that it was not man-made (even harder to tell) because you have to combine both of those probabilities, and they combined neither.
Any good scientist will tell you the P-value of their experiment.
(Note: the “consensus of scientists” is a political, not scientific, measurement if that is all they tell you).