United States

United States Department of Energy   
http://www.energy.gov/  

 

United States Department of State
http://www.state.gov/g/oes/climate

 

United States Environmental Protection Agency
http://www.epa.gov/globalwarming/

 

United States National Assessment
http://www.gcrio.org/NationalAssessment/

 

The United States Global Change Research Program (USGCRP)
http://www.usgcrp.gov

 

National Trust for Historic Preservation

http://nationaltrust.org/

 

International

United Nations Environment Program
http://grida.no/climate/

International Institute for Applied Systems Analysis
http://www.iiasa.ac.at