I work in urban agriculture and urban food security and just want to point out, coal isn't the worst offender: it's METHANE!
Methane is 25x more potent than any carbon dioxide emission. The effects of factory farming impact climate change even more than fuel emissions. One of my favorite at-a-glance illustrations was put together by the Environmental Working Group in 2011. Check it out here: http://www.ewg.org/meateatersguide/at-a-glance-brochure/
The more perspectives on ways to combat climate change, the better.