Source: Energy Information Administration

Total U.S. greenhouse gas (GHG) emissions were 6,576 million metric tons carbon dioxide equivalent (MMTCO2e) in 2009, a decrease of 5.8 percent from the 2008 level, according to Emissions of Greenhouse Gases in the United States 2009, a report released last week by the U.S. Energy Information Administration (EIA). Since 1990, U.S. GHG emissions have grown at an average annual rate of 0.4 percent. This is the largest percentage decline in total U.S. GHG emissions since 1990, the starting year for EIA's data on total GHG emissions.

"The large decline in emissions in 2009 was driven by the economic downturn, combined with an ongoing trend toward a less energy-intensive economy and a decrease in the carbon-intensity of the energy supply," said EIA Administrator Richard Newell.

Total estimated U.S. GHG emissions in 2009 consisted of 5,446.8 million metric tons of carbon dioxide (82.8 percent of total emissions); 730.9 MMTCO2e of methane (11.1 percent of total emissions); 219.6 MMTCO2e of nitrous oxide (3.3 percent of total emissions); and 178.2 MMTCO2e of hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6) (2.7 percent of total emissions). 

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