7-5 Transportation GHG Emissions by Mode: 2012
percent of TgCO2 Eq.
Mode | TgCO2 Eq. | Percent |
---|---|---|
Highway | 1,559 | 85 |
Air | 147 | 8 |
Water | 41 | 2 |
Rail | 47 | 3 |
Pipeline | 48 | 3 |
Key: GHG = greenhouse gas. TgCO2 Eq. = teragrams of carbon dioxide equivalent. A teragram = 1 million metric tons.
Note: Percents do not add to 100 due to rounding.
Source: U.S. Environmental Protection Agency, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 19902012, available at www.epa.gov/climatechange/ghgemissions/usinventoryreport.html as of September 2014.