Table 6-16 Medium- and Heavy-Duty Truck Greenhouse Gas Emissions: 1990, 2005, and 2010-2013
(millions of metric tonnes of CO2 equivalent)
| 1990 | 2005 | 2010 | 2011 | 2012 | 2013 | |
|---|---|---|---|---|---|---|
| Carbon dioxide | 230.1 | (R)395.9 | (R)388.4 | (R)386.8 | 386.8 | 393.2 |
| Methane | (R)0.3 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
| Nitrous Oxide | (R)0.7 | 1.1 | (R)1.2 | (R)1.1 | 1.1 | 1.1 |
| Hydrofluorocarbons | ≤0.05 | (R)12.7 | (R)13.2 | (R)13.3 | 13.3 | 13.3 |
| Total Truck | 231.1 | (R)409.8 | (R)403.0 | (R)401.3 | 401.4 | 407.7 |
| Total U.S. Transportation1 | (R)1,554.4 | (R)2,022.5 | (R)1,848.1 | (R)1819.7 | 1,799.8 | 1,810.3 |
| Total U.S.1 | (R)6,301.1 | (R)7,350.2 | (R)6,898.8 | (R)6,776.6 | 6,545.1 | 6,673.0 |
| Truck share of transportation total (percent) | (R)14.9 | (R)20.3 | (R)21.7 | (R)22.1 | 22.3 | 22.5 |
| Truck share of U.S. total (percent) | 3.7 | (R)5.6 | 5.9 | (R)5.9 | 5.9 | 6.1 |
KEY: CO2 = carbon dioxide; R = revised.
1Transportation and U.S. totals include greenhouse gas emissions from military aircraft (11.0 million metric tonnes in 2013); "other" transportation, primarily lubricants (8.8 million metric tonnes in 2013); and electricity-related emissions. Emissions from international bunker fuels are not included.
NOTES: CO2 equivalent is computed by multiplying the weight of the gas being measured by its estimated Global Warming Potential (GWP). The Intergovernmental Panel on Climate Change developed the GWP concept to compare the ability of one GHG to trap heat in the atmosphere to another gas. Carbon comprises 12/44 of CO2 by weight. Medium- and heavy-duty trucks weigh 8,501 pounds and above. Numbers may not add to totals due to rounding.
SOURCE: U.S. Environmental Protection Agency, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2013, EPA 430-R-15-004 (Washington, DC: April 15, 2015), tables 2-13 and ES-7, available at http://epa.gov/climatechange/ghgemissions/usinventoryreport.html as of August 2015.