Scientific American is a reliably statist publication and therefore appeals to a readership that is skewed to the left of the political center.
So 69% of these leftists say we are powerless to stop global warming, only 7% of these leftists support cap-and-trade, 78% claim global warming is from natural processes and finally 80% of the leftists said they would pay nothing to forestall the risk of catastrophic climate change.
The left doesn't seem to buy that people are causing global warming.