It was one of my favorite running jokes 'Studies show that our drinking water contains obscene amounts of dihydrogen monoxide' was always my favorite part, usually by then one of the people in the group had figured it out and looked like they were about to fall on the floor laughing, typically about the same time some know-it-all-wannabe said "It's true, I've heard about that"

Well, on to AGW.

1/2. So, do you believe that humans are causing global warming? Or is it natural?

I believe that humans are currently capable, due to our numbers and industrialization, of having major impacts on the atmosphere and biosphere, intentional or otherwise. The exact nature of that effect is debatable, but CO2 acts as an insulator in our sort of atmosphere without significantly increasing Earth's albedo (reflectivity) - most of the other factors tend to generate feedback, positive, negative, or both and current models do not reliably link the various factors together for solid predicitions, but there are heavy indications that the net effect should be warming.

I like to think of all the various effects as coffee. If you add in creamer, it stays warmer longer, but the lighter color reflects away light whereas black coffee absorbs it, so if you stick it under a very bright light (sun) it becomes a contest as to which effect dominates, and that depends on shape of the coffee mug, brightness of the light, percentage of creamer, etc. Each of the feedback cycles represent different mugs of coffee. In many cases both effects will be dwarfed by other factors, like sticking the coffee out in the snow or on a coffee warming plate. Sort of like having a white car, theoretically a white car moves faster for less fuel when moving with the sun on it's rear than a different color car, but the effect is virtually nil, however if you've seen one of those little whirlie-gigs in a bell jar with one white panel and one black, you will notice that if you flip a light on it will begin spinnning, from that very same effect.

As one might guess, I like coffee. But whatever the net effect, I think one has to acknowledge that adding creamer to coffee significantly alters the dynamics of the system, creame rof course being CO2 in this analogy, which is why I try to think of myself not so much as a AGW supporter as a Artificial Climate Change supporter, which of course mankind has been doing for millenia to greater or lesser degree, a habit we share with beavers, we're just much better at it.

3. Do you believe in global warming at all?

Too simple or complex a question, the simple answer is 'yes, of course, we have ice ages and warm spells after all' the complex answer shifts back into AGW.

4. Do you like iced tea?

It's okay, I need some mint, lemon, or rasberry in it to really enjoy it, and a bit of sugar.