|Annual change in US GHG Emissions, 1996–2004. Click to enlarge.|
The latest report on greenhouse gas emissions from DOE’s Energy Information Administration (EIA) shows a 2.0% increase in 2004 to 7,122.1 million metric tons of carbon dioxide equivalent (MMTCO2e) from 2003’s 6,983.2 MMTCO2e.
The EIA attributes the large growth in 2004 to a surging U.S. economy, which in turn resulted in more energy use. The economy grew 4.4% in 2004—the fastest since 1999—and in turn the carbon dioxide generated from energy use increased by 1.7%. But since the greenhouse emissions grew slower than the economy, the U.S. greenhouse gas intensity—the amount of greenhouse gas emissions per unit of economic output—decreased by 2.1% in 2004.
Since 1990, U.S. greenhouse gas emissions have increased by 15.8%, for an average annual increase of 1.1%.
The 2004 increase in total greenhouse gas emissions is attributable primarily to a 1.7% increase in emissions of carbon dioxide to 5,973.0 million metric tons, along with increases in emissions of nitrous oxide (5.5%) and methane (0.9%). Emissions of engineered gases—hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6)—also increased, by 9.6 percent.
|CO2 Emissions by Energy Sector|
Transportation emissions of CO2 climbed 3.1% from 2003 to 2004, and account for the largest percentage of carbon dioxide emissions (32.4%).
Almost all (98%) of transportation sector carbon dioxide emissions result from the consumption of petroleum products: motor gasoline, 1,162.6 MMT (60% of total); middle distillates (diesel fuel), 428.2 MMT(22%); jet fuel, 237.4 MMT(12%); and residual oil (heavy fuel oil, largely for maritime use), 54.6 MMT (2.8%).
The growth in transportation-related carbon dioxide emissions in 2004 included increases in emissions from the use of motor gasoline (21.2 MMT, up 1.9%), diesel fuel (17.9 MMT, up 5.1%), residual fuel oil (10.0 MMT, up 22.7%), and jet fuel (8.2 MMT, up 3.6%).