The IPCC ( http://www.ipcc.ch/ ) is the base of the public discourse by the mass media. Less know is the Nongovernmental International Panel on Climate Change with the acronym of NIPCC.
The NIPCC has also quite a bit of "recommendations" to policy makers.
Now, it is understandible which the German EPA (Umweltbundesamt) wanted to stop the public scientific discussion about the topic.
NIPCC Project Center for the Study of Carbon Dioxide and Global Change P.O. Box 25697 Tempe, AZ 85285-5697 USA