The Working Group I (The Physical Science Basis) of the IPCC has provided Frequently Asked Questions (as PDF) which have been taken directly from the chapters of the underlying Fourth Assessment Report (2007).
IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.