ScienceDaily: Total U.S. greenhouse gas (GHG) emissions were 7,282 million metric tons carbon dioxide equivalent (MMTCO 2e) in 2007, an increase of 1.4 percent from the 2006 level according to Emissions of Greenhouse Gases in the United States 2007, according to a report released December 4 by the Energy Information Administration (EIA). Since 1990, U.S. GHG emissions have grown at an average annual rate of 0.9 percent. U.S. GHG emissions per unit of gross domestic product (GDP), or U.S. GHG …