According to a new Department of Transportation (DOT) report, the United States can reduce greenhouse gas emissions by:

  1. Using low-carbon fuels
  2. Increasing vehicle fuel economy
  3. Improving system efficiency
  4. Reducing travel that involves high levels of carbon emissions

“Reducing the greenhouse gas emissions that contribute to global climate change is one of the great challenges of our time,” says Transportation Secretary Ray LaHood. “Transportation is one of the major contributors to greenhouse gases, and the transportation sector must be a big part of the solution. This report provides valuable information that will help us in our effort to protect the environment.”

The report states:

  • 29% of all U.S. greenhouse gas emissions and 5% of global emissions are caused by the fuel burned to power U.S. vehicles.
  • Almost 60% of these emissions come from light-duty vehicles, followed by freight trucks (19%) and aircraft (12%).
  • Between 1990 and 2007, greenhouse gas emissions from U.S. transportation increased 27% and accounted for almost half of the total national increase during that period.

Specific Findings

The report, while making no specific recommendations, analyzes available strategies that would reduce transportation’s greenhouse gas emissions.

Among the findings:

  • More fuel-efficient gasoline vehicles could reduce per-vehicle emissions by 8% to 30%; hybrid vehicles, 26% to 54%; and plug-in hybrids, 46% to 75%.
  • More direct routing of airline flights using NextGen technology, as well as more efficient takeoffs and landings, could reduce aviation greenhouse emissions by up to 10% by 2025.
  • Reducing the number of vehicle miles traveled through a combination of strategies—improved public transportation, coordinated transportation, land use, opportunities for walking and biking—could reduce transportation greenhouse emissions by 5% to 17% by 2030.

Policy Options

The report discusses policy options for implementing these strategies, including efficiency standards, transportation planning and investment, market-based incentives, research and development, and economy-wide carbon policies.

“Earlier this month, we established historic new fuel economy standards that will save nearly a billion tons of greenhouse gas emissions over the lives of the vehicles covered,” LaHood says. “In aviation, DOT has put energy and environmental concerns at the heart of NextGen, the initiative to modernize the U.S. air traffic system.

“The Department’s Sustainable Communities Partnership with the Environmental Protection Agency and Department of Housing and Urban Development is providing low-carbon transportation options.”

Environmental Groups Praise Report

“Ray LaHood made an important contribution to addressing climate change,” says Michael Replogle, global policy director of the Institute for Transportation and Development Policy.

“Key strategies in this report would cut emissions at less cost than most other approaches to greenhouse gas reduction when considering vehicle operating cost savings. Such smart transportation strategies would put money in the pockets of consumers and businesses, create good jobs, and support livable communities and more efficient mobility. That’s good for business, the economy and environment.”

“Congress should use the report’s findings to guide investments and policy for transportation,” adds Kathryn Phillips, an expert on federal transportation policy for the Environmental Defense Fund

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