Very good family friends, who happen to be environmentalists, began discussing very environmental things the other day, most of them I've already heard of. Global warming was, of course, mentioned, but then one of them mentioned "global dimming" in passing.

I don't know much about the issue, but he explained that it was that global dimming-- caused by CFS and sulfur particles in the air-- is actually blocking the sun from entering the atmosphere, offsetting global warming. The joke was that with everyone cleaning up their air pollution, the world will actually get hotter because it would clear up the global dimming 'problem.'

Anyone know much about this issue? The above was a JOKE, but I'm curious how much truth is in it.