A new paper (well, new a month ago) finds the more scientifically literate a person is, the less likely he is to believe that global warming poses a catastrophic threat.
Now, as much as global warming skeptics would like to draw the conclusion that the scientific evidence opposes global warming, that’s not what the study finds. It finds that in regard to the issue of global warming, scientific literacy tends to reinforce a person’s pre-existing biases: those predisposed to skepticism become more skeptical, and vice versa. The effect is stronger for the skeptics, which accounts for the overall finding.
What is interesting is that the effect does not appear to apply in general. In regard to nuclear power, the more scientifically literate a person is, the less likely he is to believe that nuclear power poses a safety risk, regardless of the person’s predispositions.
The paper notes that, in regard to nuclear power, the effect once again is stronger for those predisposed to think nuclear power is safe. Consequently, greater scientific literacy leads to greater polarization, just as with global warming. This leads the authors to the conclusion of their paper, which I won’t go into.
But curiously — unless I missed it when I skimmed the paper — they didn’t discuss, or even conjecture, why the effect was different for global warming and for nuclear power.
My guess is there are two effects being mixed together. One effect is the degree to which the scientific evidence points in one clear direction and people find that evidence convincing, and the second effect is the polarization effect that the paper emphasizes. The paper shows clearly that the first effect is not the whole story. But it seems likely to me that in nuclear power, the scientific evidence is so compelling that it dominates the polarization effect. Hence both populations move in the same direction. For global warming the polarization effect dominates, so both populations move in opposite directions.
This makes sense to me, because my reading of the climate science is that it does not support strong conclusions about the future either way. Global warming could be dangerous, or not; we just don’t know.
This is all conjecture. Hopefully someday someone will tease those effects apart. But the one thing this study says clearly is that skepticism of global warming is not the result of scientific illiteracy.