I read an article a while back that detailed that same information. It even stated that there have been several documented minor temperature shifts with the Earth over the past century. They are just blowing it up like usual. The ever growing fish story. The media hyped each and every one of them. We went from global-warming to global-cooling and then back again many times over.
I could have sworn with the media hype we were headed for an ice age in the 70's.
However, I am not saying that we don't have a pollution issue though.