Everyone is talking about global warming, but maybe global dimming is the new global warming that everyone is not looking at, many scientists don't even know what it is or that it exists.
Google global dimming and there is quite a bit of information, but this might be a start:
http://en.wikipedia.org/wiki/Global_dimming
Interestingly there are many posts on the web about what governments are doing, and yet most people posting these into their blogs and into various other locations are doing nothing themselves? It is always left to reactive rather than proactive governments to do anything. Strange world.