Also, the more a person trusts the scientists, the less personally responsible for the hypothetical global warming threat he or she feels.
If we summarize all the sign results (page 121 in the PDF file above), the U.S. people who tend to worry are (slightly) anomalously more likely to be white, male, uneducated, poor, old, non-religious, Republican (!), conservative (!), fans of new ecological values (a very strong correlation, of course), uninformed about global warming, failing to trust the media (!), distrusting experts, unconfident in science (a rather strong effect!).
Many of the correlations seem to be too weak to be significant but the result that the people who have confidence in science are less likely to be concerned about "global warming" seems rather robust.
In some sense, I find the main result kind of unsurprising, especially for those who know what does it mean for an evolutionary advantage to be "credible". Alternatively, the highly repetitive propaganda is only influencing those who have problems to notice, remember, and understand it for the first time they hear it and they I think that they end up in the uninformed category.
The people who are able to learn quickly and remember things are of course unaffected by repetitive comments and they always learn more things. Because the actual scientific results make it clear - especially with combination with common sense and experience of many people - that there is no reason for concern, the people who are able to learn and think eventually get it.