Sept. 2021

US Environmental Protection Agency

Carbon Pollution from Transportation

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Transportation and Climate Change

Burning fossil fuels like gasoline and diesel releases carbon dioxide, a greenhouse gas, into the atmosphere. The buildup of carbon dioxide (CO2) and other greenhouse gases like methane (CH4), nitrous oxide (N2O), and hydrofluorocarbons (HFCs) is causing the Earth’s atmosphere to warm, resulting in changes to the climate we are already starting to see today.

​Greenhouse gas (GHG) emissions from transportation account for about 29 percent of total U.S. greenhouse gas emissions, making it the largest contributor of U.S. GHG emissions. Between 1990 and 2019, GHG emissions in the transportation sector increased more in absolute terms than any other sector.

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EPA Programs to Reduce Carbon Pollution from Transportation

EPA is addressing climate change by taking the following actions to reduce GHG emissions from the transportation sector. Many of these programs have benefits beyond cutting carbon. For example, decreasing fuel consumption can reduce our dependence on foreign oil and save consumers money at the pump.

Setting GHG Emissions Standards for Cars and Trucks

EPA and DOT issued a joint rule-making that set GHG emissions and fuel economy standards for the largest sources of greenhouse gases from transportation, including cars, light trucks, and heavy-duty trucks.

Light-duty GHG regulations for passenger vehicles and trucks are projected to:

  • Cut 6 billion metric tons of GHG emissions over the lifetimes of the vehicles sold in model years 2012-2025 and allowing manufacturers flexibility in meeting the standards;
  • Nearly double the fuel efficiency while protecting consumer choice; and
  • Reduce America’s dependence on oil and provide significant savings for consumers at the pump.

Heavy-duty GHG regulations are projected to:

  • Reduce CO2 emissions by about 270 million metric tons over the life of vehicles built under the program, saving about 530 million barrels of oil; and
  • The proposed “Phase 2” program includes standards that would further reduce GHG emissions and improve the fuel efficiency of medium and heavy-duty trucks.

Increasing the Use of Renewable Fuels

Congress created the Renewable Fuel Standard program in an effort to reduce greenhouse gas emissions and expand the nation’s renewable fuels sector while reducing reliance on imported oil. Renewable fuels are produced from plants, crops and other biomass, and can reduce greenhouse gas emissions when compared to burning the fossil fuels they replace.

Taking First Steps to Set a Greenhouse Gas Standards for Aircraft

EPA along with the Federal Aviation Agency at the United Nations’ International Civil Aviation Organization have developed international carbon dioxide emissions standards for aircraft. EPA is also now working through the process of potentially setting domestic regulations under the Clean Air Act that address GHG emissions from certain classes of engines used in aircraft.