Climate Change
Sources of Greenhouse Gas Emissions
- Overview
- Electricity
- Transportation
- Industry
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Commericial
& Residential - Agriculture
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Land Use
& Forestry
Transportation Sector Emissions
![photo of traffic photo of traffic](https://webarchive.library.unt.edu/web/20120925153813im_/http://www.epa.gov/climatechange/images/ghgemissions/traffic_banner.png)
Total U.S. Greenhouse Gas Emissions by Economic Sector in 2010
![Pie chart of total U.S. greenhouse gas emissions by economic sector in 2009. 34 percent is from electricity, 27 percent is from transportation, 20 percent is from industry, 11 percent is from commercial and residential, and 7 percent is from agriculture. Pie chart of total U.S. greenhouse gas emissions by economic sector in 2009. 34 percent is from electricity, 27 percent is from transportation, 20 percent is from industry, 11 percent is from commercial and residential, and 7 percent is from agriculture.](https://webarchive.library.unt.edu/web/20120925153813im_/http://www.epa.gov/climatechange/images/ghgemissions/sources-transportation.png)
Total Emissions in 2010 = 6,633 Million Metric Tons of CO2 equivalent
Related Links
The Transportation sector includes the movement of people and goods by cars, trucks, trains, ships, airplanes, and other vehicles. The majority of greenhouse gas emissions from transportation are CO2 emissions resulting from the combustion of petroleum-based products, like gasoline, in internal combustion engines.The largest sources of transportation-related greenhouse gas emissions include passenger cars and light-duty trucks, including sport utility vehicles, pickup trucks, and minivans. These sources account for over half of the emissions from the sector. The remainder of greenhouse gas emissions comes from other modes of transportation, including freight trucks, commercial aircraft, ships, boats, and trains as well as pipelines and lubricants.
Relatively small amounts of methane (CH4) and nitrous oxide (N2O) are emitted during fuel combustion. In addition, a small amount of hydrofluorocarbon (HFC) emissions are included in the Transportation sector. These emissions result from the use of mobile air conditioners and refrigerated transport.
Emissions and Trends
In 2010, greenhouse gas emissions from transportation accounted for about 27% of total U.S. greenhouse gas emissions, making it the second largest contributor of U.S. greenhouse gas emissions after the Electricity sector. Greenhouse gas emissions from transportation have increased by about 19% since 1990. This historical increase is largely due to increased demand for travel and the stagnation of fuel efficiency across the U.S. vehicle fleet. The number of vehicle miles traveled by passenger cars and light-duty trucks increased 34% from 1990 to 2010. The increase in travel miles is attributed to several factors, including population growth, economic growth, urban sprawl, and low fuel prices over much of this period. Between 1990 and 2004, average fuel economy among new vehicles sold annually declined, as sales of light-duty trucks increased. However, new vehicle fuel economy began to improve in 2005, largely due to a lower light-duty truck market share and higher fuel economy standards.
To learn about projected greenhouse gas emissions to 2020, visit the U.S. Climate Action Report 2010 (PDF). (193 pp, 3.1 MB)
Greenhouse Gas Emissions from Transportation
![Line graph of greenhouse gas emissions from transportation for 1990 to 2009. The greenhouse gas emissions started just above 1,500 million metric tons of carbon dioxide equivalents in 1990, and rose to a peak of just below 2,000 million around 2007. At the end of the time span, the line starts to dip and ends around 1,800 million metric tons of carbon dioxide equivalents in 2009. Line graph of greenhouse gas emissions from transportation for 1990 to 2009. The greenhouse gas emissions started just above 1,500 million metric tons of carbon dioxide equivalents in 1990, and rose to a peak of just below 2,000 million around 2007. At the end of the time span, the line starts to dip and ends around 1,800 million metric tons of carbon dioxide equivalents in 2009.](https://webarchive.library.unt.edu/web/20120925153813im_/http://www.epa.gov/climatechange/images/ghgemissions/GHGEmissionsFromTransportation.png)
Note: All emission estimates from the Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2010.
Reducing Emissions from Transportation
There are a variety of opportunities to reduce greenhouse gas emissions associated with transportation. The table shown below categorizes these opportunities and provides examples. For a more comprehensive list, see Chapter 5 of the Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change
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Type | How Emissions are Reduced | Examples |
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Fuel Switching | Using fuels that emit less CO2 than fuels currently being used. Alternative sources can include biofuels; hydrogen; electricity from renewable sources, such as wind and solar; or fossil fuels that are less CO2-intensive than the fuels that they replace. Learn more about Alternative and Renewable Fuels. |
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Improving Fuel Efficiency with Advanced Design, Materials, and Technologies | Using advanced technologies, design, and materials to develop more fuel-efficient vehicles. |
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Improving Operating Practices | Adopting practices that minimize fuel use. Improving driving practices and vehicle maintenance. Learn about how the freight transportation industry can reduce emissions through EPA's SmartWay Program. |
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Reducing Travel Demand |
Employing urban planning to reduce the number of miles that people drive each day. |
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