They're twins, but which one is evil?

Here.

I particularly enjoyed this inane argument from the comment section:

Besides, if the sceptics are right and the world is warming because of non-anthropogenic factors, that's actually a bigger problem. If human influence is so weak, it means that we're going to have to make _greater_ efforts to stop climate change, not less. That is, if human-caused CO2 levels have a smaller effect than is generally thought then we have to reduce emissions by a lot more than is generally thought if we want to stop a particular amount of warming!