I have had the rare occasion recently to discuss "controversial" science with non-scientist skeptics (read: family). I generally avoid politics and other such topics (the old "no politics or religion" plan), but naively thought that I would be safe discussing global warming. I was wrong.
Now, perhaps I should first comment that in some ways it's good that people are skeptical. It shows an engaged mind unwilling to be brainwashed. The family I was talking to have read up in great detail (more than I have, certainly) on global warming and know all the "arguments" against believing that it's human-caused. They've probably even read some "scientific" papers on the subject, and are generally unwilling to believe that something is true just because a newspaper says so (something that would have been welcome during the "there are WMDs in Iraq" era). And because they do take the time to learn about such topics, they don't fall victim to some of the more ridiculous anti-science theories (ahem: vaccines). But in the case of global warming, their skepticism isn't serving truth.
Why not? I believe the main reason is because of the scientific complexity of the issue. I certainly can't understand, in great detail, all of the arguments making the case that human actions are causing global warming. And I'm used to reading scientific papers. Obviously then, it's much harder for a non-scientist to understand the arguments. And how can you believe something you can't understand? Of course, politicians and oil companies (and politicians paid off by oil companies) are all preying on this to try to convince the world (non-scientist) public that those scientists are making everything up.
So what can we do? I'm actually glad that I stumbled into this argument, though it goes against my policy of "no politics or religion" with family. I think it's important that, as scientists, we stand up for science. Science needs better PR, and a good way to start is for all of us to take the responsibility of confronting the skepticism of people who already trust us.