You can read scientific reports about climate change and global warming till your eyes blur, but sometimes, good old-fashioned photos still tell the story best.

Check out this BBC photo essay documenting climate change:
http://news.bbc.co.uk/1/shared/spl/hi/picture_gallery/05/sci_nat_how_the_world_is_changing/html/1.stm

Source: http://www.tompaine.com/index.php#passiton