Project Objective

The objective of this research is to determine what alternative scenarios will be most likely to achieve the major reductions in GHGs that are needed by 2050.  Analyses will be based on an examination of existing policy and regulations covering vehicles and fuels, and will be supplemented with an analysis of how land use change and transit can contribute to GHG reductions.  Demand management options that have the potential to provide some additional reductions will also be included, as will an examination of intercity and freight transportation.

Principal Investigator

Caroline J. Rodier, Ph.D., Associate Director, Urban Land Use and Transportation Center, University of California, Davis

Student Assistant

One San José State University student research assistant will be hired to assist with this project.

Team Member

Robert B. Noland, Ph.D., Director, Alan M. Voorhees Transportation Center, Edward J. Bloustein School of Planning and Public Policy Rutgers, The State University of New Jersey

Christopher Hanson, Post-doctoral Researcher, Alan M. Voorhees Transportation Center, E.J. Bloustein School of Planning and Public Policy, Rutgers University

Project Abstract

The transportation sector under a low emissions world looks vastly different from the transportation sector we have now. It would be helpful to envision different transportation futures that would be consistent with the agreement that the United States and other nations have made. (Under the United Nations Framework Convention on Climate Change, nations agreed to limit global warming to 2°C (3.6°F), which would require cutting global greenhouse gas emissions in the range of 50 to 85%, with developed nations likely needing to be on the high end of that range). The proposed study would be a broad brush look at what the transportation sector might look like and what implications that would have for the US Department of Transportation and national transportation policy. Such a broad look would complement well the work that has been done by the US DOT in the 2010 report to Congress and by the Transportation Research Board.  This research will specifically focus on accounting for current policy trends and identifying what additional measures will be needed to achieve these major reductions in GHG emissions from transportation, by examining several alternative scenarios.

Task Description

1. Literature Review
   
   The large body of literature on climate change forecasts and the effectiveness of different strategies by mode for the transportation sector will be reviewed to:
   • Identify the latest estimates of greenhouse gas reductions from the U.S. transportation sector by mode that would be required to meet the United Nations Framework Conventions agreement on Climate Change. As possible, the review will identify key uncertainties in these estimates as well as likely high and low bounds on the estimates.
   • Summarize available strategies and best estimates of their relative effectiveness with respect to GHG reductions, and, as available, evidence of costs and benefits. Strategies will include low-carbon fuels, vehicle fuel efficiency, and travel demand management, such as auto pricing, transit investments, and land use planning.
   • Identify current trends and regulations mainly for vehicle efficiency standards and low carbon and renewable fuels.  We will review current knowledge on fuels to determine whether existing targets will be met and whether these will provide the GHG reductions that are expected, as many of the current forecasts have been overly optimistic.
2. Future Scenarios
   
   The results of the literature review will be used to develop three to five potential future scenarios, in which different and complementary strategies will be implemented to achieve GHG reduction goals. Information on the respective strategies’ costs, benefits, and barriers to implementation will be used to inform scenario construction.  Researchers will use the results of the literature review to provide quantitative evidence on the magnitude of likely GHG reductions from the scenarios as well as more qualitative or theoretical analyses of the likely effects of these scenarios with respect to the economy, environment, health, and equity. Synergies among the strategies in the scenarios and key uncertainties will be explicitly considered and evaluated. 
3. Scenario Simulations
   
   The most promising scenarios will then be simulated with an activity-based microsimulation travel model for the state of California and the latest emissions model implemented by the California Air Resources Board. The results of the simulations will be used to refine our understanding of type, magnitude, and combination of travel demand management, fuel, and technology strategies necessary to achieve GHG reduction goals. In addition, the performance of these scenarios under changing socio-economic trends can also be evaluated (e.g., distribution of income, household size, and vehicle availability).  The simulation of these scenarios will allow for a consistent evaluation of  the economic and equity effects of scenarios, for example, change in travel time and cost by mode to destinations of significant economic importance and by household income groups.  This study will also be one of the first to quantify synergies among travel demand management strategies.  Future forecasts are available for 2020, 2035, and 2050 time horizons.

Technology Transfer

The results of this research will be presented at the Transportation Research Board and other important transportation and climate change conferences. In addition, research results will be published in one or more peer reviewed transportation journals.

Potential Benefits of Project

The specific outcomes will include the identification of what additional policies are likely to be needed in all of the aforementioned areas and for all modes.  This will provide useful information for policy makers and local decision makers on what policies they should pursue to most cost effectively achieve reductions.