U.S. Climate Action Report--2006: Fourth National Communication of the United States of America under the United Nations Framework Convention on Climate Change [open pdf - 35MB]
"The fourth CAR [Climate Action Report] provides an update on key activities conducted by the U.S. since the third CAR, an inventory of U.S. greenhouse gas emissions and sinks, an estimate of the effects of mitigation measures and policies on future emissions levels, and a description of U.S. leadership and involvement in international programs, including associated contributions and funding efforts. In addition, the text discusses U.S. national circumstances that affect U.S. vulnerability and responses to climate change. Finally, the CAR presents information on the U.S. Climate Change Science Program, the U.S. Climate Change Technology Program, our efforts in systematic observations, including the U.S. Integrated Earth Observation System, and our education, training and outreach efforts. The report takes into account activities up to and including 2006."
Bureau of Oceans and International Environmental and Scientific Affairs: http://www.state.gov/g/oes/