The U.S. transportation sector generates more carbon dioxide emissions than the entire economy of any other country in the world with the exception of China, according to a study released yesterday by the Pew Center on Global Climate Change. The study, “Reducing Greenhouse Gas Emissions from U.S. Transportation,” also found that transportation accounts for almost one-third of all U.S. CO2 emissions and seven in every 10 barrels of oil consumed by the country. As Pew Center President Eileen Claussen noted, that means “reducing emissions from this system is critical to an effective GHG [greenhouse gas] reduction strategy.” Using existing technology and implementing mandatory policies could cut those emissions in half by 2030, the report found.