Center for Climate and Energy Solutions
http://www.c2es.org/science-impacts/basics/
Stanford School of Earth, Energy and Environmental Sciences
https://pangea.stanford.edu/programs/outreach/climatechange/
Will Steiger Foundation
http://www.willstegerfoundation.org/climate-change-basics/basics
Pew Climate- Realities and Misconceptions about Climate Change
http://www.pewclimate.org/science-impacts/realities-vs-misconceptions
Skeptical Science: IPCC Facts