Carbon dioxide emissions from fossil fuel use in the United States fell 2.8 percent in 2008, the largest annual drop in more than 20 years, reports the Energy Information Administration. A slowing economy and high gasoline prices contributed to the decline.
Emissions fell for all major fossil fuels: emissions from petroleum fell 6 percent, natural gas dipped 1 percent, and coal retreated 1.1 percent.
Emissions also fell across most end-use sectors including electricity generation (down 2.1 percent), industrial use (down 3.2 percent), and transportation (down 5.2 percent). The only sector to see a rise in emissions was commercial, which increased 0.5 percent.
Despite the largest decline since 1990, the transportation sector remained the largest end-use source of energy-related CO2 emissions. Since 1990, transportation sector carbon dioxide emissions have risen by 21.1 percent — 1.1 percent per year.
The carbon efficiency of the economy also improved, with emissions per unit of GDP dropping 3.8 percent in 2008.
U.S. emissions from fossil fuel burning in 2008 were 15.9 percent above the 1990 level (the baseline for the 1997 Kyoto Protocol) and 2.8 percent below the 2005 level (the baseline proposed under the American Clean Energy and Security Act of 2009 [Waxman-Markey bill]).