Time: Today the scientific community is in almost total agreement that the earths climate is changing as a result of human activity, and that this represents a huge threat to the planet and to us. According to a Pew survey conducted in March, however, public opinion lags behind the scientific conclusion, with only 69% of those surveyed accepting the view that the earth is warming -- and only 1 in 4 Americans see global warming as a major threat. Still, 69% is a solid majority, which begs the question,...