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The Center's Research

Research Areas

Impact Of Climate Variability and Change On Transportation

Research to examine the effects that climate change and variability may have on transportation infrastructure and services, and to identify potential adaptation strategies for use by transportation decision-makers, operators, state and local planners, and infrastructure builders. Studies on specific aspects of this issue are undertaken as part of a multi-year program, based in part upon the results of an October 2002 workshop (see project listing below).

Increasing energy efficiency and reducing greenhouse gas emissions

Research to reduce energy usage covering mitigation of transportation's environmental impacts both through conservation and through the application of new technology.

Modeling

Research to develop and improve analytical tools for transportation energy use to support decision making throughout the government and in the private sector.

Institutional Capacity Building

Research to analyze the prevailing institutional frameworks that support or constrain the implementation of GHG emission reduction strategies.

Research Projects

Impact of Climate Variability and Change on Transportation

Ongoing Projects

  • The Impacts of Climate Change and Variability on Transportation Systems and Infrastructure: Gulf Coast Study. The DOT Center is partnering with the U.S. Geological Survey to undertake a multi-year research program to study how short and long-term changes in climate could affect transportation systems in the U.S. central Gulf Coast region, and how transportation decision-makers could address possible impacts. This study is one of the CCSP's twenty-one synthesis and assessment products.
     
  • Effects of Sea Level Rise on National Transportation Infrastructure. The study uses multiple data sources to quantify the potential impact of sea level rise on land and transportation infrastructure in coastal areas of the eastern United States. The study will provide several relevant pieces of information imperative to the security of our infrastructure, including: (1) digital elevation models (DEMs) to describe the elevation in the coastal areas and create tidal surfaces to describe the current sea water levels; (2) identify land and transportation infrastructure that, without protection, will be inundated regularly by the ocean or be at risk of periodic inundation due to storm surge; and (3) provide statistics to demonstrate the potential extent of inundated and at-risk land surge at given temporal intervals. Research conducted by ICF International. This project is also listed below in the "Modeling" research area.
     
  • Transportation and Climate Change Study. The Center is partnering with the Transportation Research Board of the National Academies to conduct a study to examine strategies to reduce greenhouse gas emissions as well as transportation policy options for adapting to the potential impacts of climate change. The study will include as a centerpiece a major conference with commissioned papers that is designed to foster and expand dialogue and awareness about the potential risks and consequences of climate change. A committee of experts assembled for this effort will issue a report with findings and recommendations regarding needed research and actions to prepare for climate change. This project is also listed below in the "Increasing Energy Efficiency and Reducing Greenhouse Gas Emissions" research area. 
     
  • Workshop on Impacts of Global Climate Change on Hydraulics and Hydrology and Transportation. The Center is partnering with the Center for Transportation and the Environment at the North Carolina State University to develop guidelines for practitioners dealing with the consequences of climate change. The purpose of this initiative is to provide these planning and engineering professionals with the information they need to make informed decisions on how to respond to the potential impacts of climate change related to hydrologic impacts. CTE will conduct two workshops to define and develop the guidance. The final results will be presented at a nationally televised videoconference as well as submitted for publication as a special edition of a technical journal.

Completed Projects

  • The Potential Impacts of Climate Change on Transportation Workshop. DOT's Center for Climate Change and Environmental Forecasting, the Environmental Protection Agency, the Department of Energy, and the US Global Change Research Program co-sponsored this workshop on October 1-2, 2002 to discuss the potential impacts of climate change on transportation systems and services. The DOT Center is undertaking a multi-year research program to study how short and long-term changes in climate could affect transportation, and how transportation decision-makers could address possible impacts. The workshop brought together 64 transportation and planning professionals and experts in climate change and assessment to explore these issues and provide input on the research questions that should be given top priority for investigation by the Center.

Increasing Energy Efficiency and Reducing Greenhouse Gas Emissions

Ongoing Projects

  • Transportation and Climate Change Study. The Center is partnering with the Transportation Research Board of the National Academies to conduct a study to examine strategies to reduce greenhouse gas emissions as well as transportation policy options for adapting to the potential impacts of climate change. The study will include as a centerpiece a major conference with commissioned papers that is designed to foster and expand dialogue and awareness about the potential risks and consequences of climate change. A committee of experts assembled for this effort will issue a report with findings and recommendations regarding needed research and actions to prepare for climate change. This project is also listed above in the "Impact of Climate Variability and Change on Transportation" research area. 
     
  • Reducing the GHG & Air Quality Impacts of Freight Transportation. This project focuses on the identification of measures to lower GHG emissions from freight by analyzing the rail and marine replacement of truck freight. The analysis will provide information regarding freight contributions to GHG emissions and, given the projected growth in freight movement, will be valuable to state Departments of Transportation (DOTs) and Metropolitan Planning Organizations (MPOs) in implementing strategies to reduce freight-related GHG emissions. Research conducted by the Center for Clean Air Policy. 
     
  • Assessment of Greenhouse Gas Emissions Benefits of Heavy Duty Natural Gas Vehicles in the U.S. This project seeks to improve the understanding of the GHG emissions reduction potential of heavy-duty natural gas and diesel vehicles. This will be achieved by evaluating years of carbon dioxide as well as other transportation-related GHG emissions data, including methane and nitrous oxide, from a previously untapped data source at West Virginia University's National Research Center for Alternative Fuels, Engines and Emissions. Currently, the widely used accounting protocols do not give accurate estimates of CO2, CH4, and N2O emissions in determining the emissions benefits of heavy-duty vehicles and engine technologies. The results of this research will be summarized in a report, which will include a discussion of heavy-duty natural gas vehicles and engine technologies that may have a lower GHG impact than conventional diesel engines. Research conducted by Science Applications International Corporation. 
     
  • Multi-Partner Cooperative Research Agreement for Greenhouse Gas and Other Emission Reductions Aboard a Large Container Vessel. This project funds a literature search and technology assessment and the physical survey of a container vessel in order to install and test various emission reduction systems aboard a vessel, that were previously installed in shore-side power plants. Phase II, consisting of the installation and testing of the systems, and Phase III, including the calculation of the resulting air emissions reductions, would be funded by other partners in this project.

Completed Projects

  • Integrating Transportation, Energy Efficiency, and GHG Reduction Policies: A Guidebook for State and Local Policy Makers. This project presents a unique opportunity to work with EPA to develop a guidebook that evaluates the emission impacts of transportation policy measures. The project complements EPA's focus on demand-side measures with an additional section on quantification and evaluation of vehicle technologies and fuel policies. The guidebook is a resource for state DOTs and MPOs in establishing GHG inventories and deciding among various mitigation strategies. Research conducted by the Center for Clean Air Policy. 
     
  • Assessing State Long-Range Transportation Planning Initiatives in the Northeast for Climate Energy Efficiency Benefits. This project identifies tools and methodologies to help the Northeastern states develop and implement strategies to reduce GHG emissions through the statewide, long-range transportation planning process. This research will raise the awareness among state transportation planners for correlating long-range plans with statewide GHG emissions. It will also provide best practices and methods by which states can integrate GHG-reduction/mitigation goals in their long-range plans. Research conducted by The BBG Group. 
     
  • Estimating Transportation-Related Greenhouse Gas Emissions and Energy Use in New York State. This project, done in partnership with the New York State Department of Transportation, studies the development and the implementation of the New York State Energy Plan (SEP), focusing on the transportation-related components of the SEP. Research conducted by ICF Consulting.
     
  • Transportation Emissions Charges: Analysis of Costs to Achieve Emissions Reductions. Phase I of this project funds a literature search for cost-benefit analysis reports on charging systems to reduce emissions in any transportation mode. The information allows DOT to respond to advocates of fees and charges and supports the Administration's voluntary approach to emission reductions. 
     
  • Greenhouse Gas Reduction Through State and Local Transportation Planning. This project evaluates how and why states, metropolitan planning organizations, cities, and transportation providers are pursuing GHG emission reductions, with a focus on transportation planning. The research improves understanding of how states and localities might contribute to GHG reduction through transportation decisions. Research conducted by the Volpe National Transportation Systems Center. 
     
  • Fuel Options for Reducing Greenhouse Gas Emissions from Motor Vehicles. This project reviews several alternatives to current transportation fuels. Fuels included in the analysis include gasoline, ethanol, methanol, natural gas, liquefied petroleum gas, reformulated diesel, biodiesel, electricity, and hydrogen. Each fuel is under consideration as part of an overall vehicle/fuel system, and is characterized both in near and longer-terms based on economics, expected fuel-cycle emissions and energy consumption. Research conducted by the Volpe National Transportation Systems Center. 
     
  • Highway/Transit/Ferry Integration. This project evaluates the potential greenhouse gas benefits achievable through better integration of passenger ferries with land transportation systems, considering ferry technology and fueling options. The San Francisco Bay Area is analyzed as a point of reference and as a potential basis for consideration of other areas where passenger ferries might be effective. Research conducted by CALSTART.

Modeling

Ongoing Projects

  • Effects of Sea Level Rise on National Transportation Infrastructure. The study uses multiple data sources to quantify the potential impact of sea level rise on land and transportation infrastructure in coastal areas of the eastern United States. The study will provide several relevant pieces of information imperative to the security of our infrastructure, including: (1) digital elevation models (DEMs) to describe the elevation in the coastal areas and create tidal surfaces to describe the current sea water levels; (2) identify land and transportation infrastructure that, without protection, will be inundated regularly by the ocean or be at risk of periodic inundation due to storm surge; and (3) provide statistics to demonstrate the potential extent of inundated and at-risk land surge at given temporal intervals. Research conducted by ICF International. This project is also listed above in the "Impact of Climate Variability and Change on Transportation" research area. 
     
  • Emissions Analysis of Freight Transport Comparing Land-Side and Water-Side Short-Sea Routes: Development and Demonstration of a Decision Modeling Tool. This study is aimed at developing a methodology and tools to effectively compare emissions from land-side and water-side freight transport alternatives. The research team will develop and demonstrate a model that analyzes total fuel-cycle GHG and other emissions associated with transporting freight along land-side and water-side routes. The project will also evaluate tradeoffs among pollutants, costs, and travel time for moving freight between two points and will identify optimal modal combinations within a network of travel paths that would lead to minimizing emissions, costs, and/or travel time. Research conducted by the University of Delaware, College of Marine Studies.
     
  • Holistic Comparative Analysis of Emissions from Aviation, Automobile, Marine, and Diesel Transports. This project compares emissions datasets from aviation, heavy-duty diesel, automobile and marine vehicles and analyzes the similarities and differences across the transportation modes. The final report will focus on how the analyzed data can be added to existing emission inventories for the respective transportation modes and used in quantifying contributions to local and regional air quality and global climate change. The research will help inform decision makers on which environmental impact mitigation strategies offer the biggest impact in the most cost effective manner across all modes in the transportation sector. Research conducted by Aerodyne Research, Inc. 
     
  • Total Fuel Cycle Emissions for Marine Transportation: Development of a "Well-to-Hull" Modeling Tool. This project will develop a "well-to-hull" modeling tool to estimate total fuel cycle emissions from marine transportation and will lay the groundwork for future research. The research will provide equivalent modal comparison information that may support short sea shipping initiatives and ferry use as alternatives to surface transportation. Research conducted by the Rochester Institute of Technology. 
     
  • Feasibility of Utilizing the National Energy Modeling System (NEMS) as a Broad Integrating Framework for Greenhouse Gas Emissions Modeling in the Transportation Sector. This project will investigate the feasibility of integrating NEMS with other transportation models to enhance the analytical capabilities beyond those which any individual model can offer. An integrated framework of models will enable a more comprehensive approach to transportation sector modeling. Combining an existing travel demand model with a broadened NEMS to develop a framework for a multi-modal approach to study/develop transportation emission policy analysis will help transportation planners and others in the transportation community to measure the economic benefits, such as GDP and national income, associated with various transportation policies. Research conducted by Science Applications International Corporation. 
     
  • Measuring the Greenhouse Gas Intensity of the Transportation Sector. This project will explore two measurement approaches for GHG emissions from transportation: (1) transportation emissions per unit of GDP or transportation GDP and (2) intensity per passenger-mile or ton-mile. In both cases, the project considers transportation as a sector, by mode, and by its passenger and freight components. 
     
  • Characterization of Power Plant Emissions and Fuel Quality and Consumption Rates of the U.S. Waterborne Fleet. This project creates a comprehensive database organized on a per-vessel basis and provides the ability to sort according to various emissions parameters. It will assist in the analysis of factors contributing to emissions generation, primary locations of emission sources, types of vessels, and prevalent propulsion equipment and fuel types. Research conducted by the University of Delaware.

Papers and Presentations

As DOT staff deliver public presentations and papers on behalf of the Center, these will be made available through the Center's website.

  • Emissions Analysis of Freight Transport Comparing Land-Side and Water-Side Short-Sea Routes: Development and Demonstration of a Freight Routing and Emissions Analysis Tool (FREAT). This study is aimed at developing a methodology and tools to effectively compare emissions from land-side and water-side freight transport alternatives. The research team will develop and demonstrate a model that analyzes total fuel-cycle GHG and other emissions associated with transporting freight along land-side and water-side routes. The project will also evaluate tradeoffs among pollutants, costs, and travel time for moving freight between two points and will identify optimal modal combinations within a network of travel paths that would lead to minimizing emissions, costs, and/or travel time. Research conducted by the University of Delaware, College of Marine Studies.
     
  • The Impacts of Climate Change and Variability on Transportation Systems and Infrastructure: Gulf Coast Study.The DOT Center is partnering with the U.S. Geological Survey to undertake a multi-year research program to study how short and long-term changes in climate could affect transportation systems in the U.S. central Gulf Coast region, and how transportation decision-makers could address possible impacts. This study is one of the CCSP's twenty-one synthesis and assessment products.
     
  • The Potential Impacts of Global Sea Level Rise on Transportation Infrastructure. The study uses multiple data sources to quantify the potential impact of sea level rise on land and transportation infrastructure in coastal areas of the eastern United States. The study will provide several relevant pieces of information imperative to the security of our infrastructure, including: (1) digital elevation models (DEMs) to describe the elevation in the coastal areas and create tidal surfaces to describe the current sea water levels; (2) identify land and transportation infrastructure that, without protection, will be inundated regularly by the ocean or be at risk of periodic inundation due to storm surge; and (3) provide statistics to demonstrate the potential extent of inundated and at-risk land surge at given temporal intervals. Research conducted by ICF Consulting. This project is also listed below in the "Modeling" research area.
     
  • Integrating Transportation, Energy Efficiency, and GHG Reduction Policies: A Guidebook for State and Local Policy Makers. This project presents a unique opportunity to work with EPA to develop a guidebook that evaluates the emission impacts of transportation policy measures. The project complements EPA's focus on demand-side measures with an additional section on quantification and evaluation of vehicle technologies and fuel policies. The guidebook is a resource for state DOTs and MPOs in establishing GHG inventories and deciding among various mitigation strategies. Research conducted by the Center for Clean Air Policy. 
     
  • Workshop on the Impacts of Aviation on Climate Change. Aviation is integral to the global economy and transportation. Its demand is projected to triple by 2025. However, a lack of understanding of aviation impacts on environment, and hence the appropriate action, could impede that growth. The climate impact of emissions is aviation's primary long-term environmental issue. The FAA and NASA co-sponsored a workshop on this issue to: review the current state of knowledge; identify gaps in scientific knowledge and prioritize research; recommend leveraging current and future research; and explore development of impact metrics for evaluating impacts and tradeoff options. This workshop, which was attended by more than 30 international science experts, recommended coordination and expansion of existing and planned climate research programs focusing on aviation. The workshop's findings and recommendations are presented in this report.
     
  • Assessment of the Greenhouse Gas Emission Benefits of Heavy Duty Natural Gas Vehicles in the United States. Assessment of Greenhouse Gas Emission Benefits of Heavy Duty Natural Gas Vehicles in the United States. More accurate emission factors for heavy duty vehicles are necessary as organizations are proactively implementing fuel switching projects and purchasing natural gas vehicle fleets, and claiming GHG benefits. GHG reduction estimates for fuel switching projects are often based on estimates of CO2 only, without considering increases in CH4 emissions from natural gas vehicles. To address this knowledge gap, SAIC and WVU extracted previously unpublished data from heavy duty vehicle tests undertaken by WVU and analyzed CO2 and CH4 emissions from different fuels, vehicle types, engine technologies, and drive cycles. Although the data are insufficient to draw universal conclusions about natural gas relative to diesel use and the resulting emission factors were not statistically significant, the CO2 and CH4 data results for CNG buses tested by WVU are generally consistent with the results of recent emission tests on some of the same vehicle types, fuel types, and drive cycles. The available data suggest that for refuse trucks and school buses operating in conditions similar to the central business district driving cycle, total GHG emissions from natural gas-fueled vehicles may be equivalent or greater than diesel-fueled vehicles.
     
  • Assessing State Long Range Transportation Planning Initiatives in the Northeast for Climate and Energy Benefits. This study identifies best state long range transportation planning (LRTP) practice for climate protection and energy efficiency outcomes. Given rapidly rising levels of domestic oil consumption and growing global attention to the challenge of GHG emissions, an analysis of strategic transportation planning initiatives to address how well energy and climate change issues are addressed in long range transportation planning is important. On the basis of interviews with LRTP professionals, a literature search, and a review of state LRTPs in the 29 states with Climate Action Plans, or gubernatorial initiatives directing state agencies to coordinate planning for climate and energy efficiency outcomes, 15 state transportation plans were selected to further evaluate long range planning processes that contain both a specific intention to integrate climate and energy outcomes into long range transportation planning and achieve best practice by state Department of Transportations (DOTs).
     
  • Estimating Transportation-Related Greenhouse Gas Emissions and Energy Use in New York State. This report, completed in partnership with the New York State Department of Transportation (NYSDOT), assesses the transportation-related components of the New York State Energy Plan (SEP). The goals of the project included: the development of baseline and projected energy use and CO2 emissions for the State and by sector; the development of baseline and projected energy use and CO2 emissions for each metropolitan planning organization (MPO) in the State by mode; an assessment of MPO experiences and responses to the new energy/GHG analysis contained in the SEP; and, the evaluation of potential energy savings and GHG reductions from selected transportation strategies.
     
  • Stock Modeling for Railroad Locomotives and Marine Vessels. Relying on available historical data regarding the domestic introduction and in-service populations of locomotives and marine vessels, this report estimates corresponding survival curves; that is, functions that describe the fraction of equipment likely to remain in service after a given number of years of service. Survival curves are used to, among other things, estimate the impact new equipment will have on future energy and emissions. For light-duty highway vehicles, for which available information is robust, such survival curves are well developed. Information regarding locomotives and marine vessels is much more scarce. Consistent with anecdotal evidence, this report estimates that locomotives and marine vessels remain in service considerably longer than light-duty highway vehicles.
     
  • Greenhouse Gas Reduction Through State and Local Transportation Planning. Evaluates how states and local areas might contribute to GHG emission reduction through transportation planning. Seven case studies focus on the broad transportation planning process, strategies and other actions selected, and GHG emission reductions accomplished or projected. Considers both transportation planning by state DOTs, metropolitan planning organizations, and local transportation agencies, and energy, environmental, or land use planning by other state and local agencies that considers climate change and transportation policies, investments, and strategies.
     
  • Fuel Options for Reducing Greenhouse Gas Emissions from Motor Vehicles. An assessment of the potential of gasoline substitutes to reduce emissions of carbon dioxide and other greenhouse gases by automobiles and light-duty trucks. Reductions in future GHG emissions are estimated under specific assumptions about growth in light-duty vehicle travel and the replacement of gasoline by various other fuels, both in the near term (10 years) and over the longer term (25 years).
     
  • Modeling of Advanced Technology Vehicles. Reviews some currently-used methods for representing advanced technology vehicles in engineering and market simulation models, and considers the potential for simple generalized methodologies for use in the latter. Focuses on light-duty hybrid electric vehicles as an illustrative case and also considers possible extension to other vehicle types (e.g., aircraft, buses, locomotives, and marine vessels).
     
  • Passenger Ferries, Air Quality, and Greenhouse Gases: Can System Expansion Result in Fewer Emissions in the San Francisco Bay Area? Evaluates the potential greenhouse gas benefits achievable through better integration of passenger ferries with land transportation systems, considering ferry technology and fueling options. The San Francisco Bay Area was analyzed as a point of reference and as a potential basis for consideration of other areas where passenger ferries might be effective. 
     
  • The Potential Impacts of Climate Change on Transportation: Workshop Summary and Proceedings.
    Summary and eighteen discussion papers from October 2002 workshop exploring the potential impacts of climate change on transportation systems and services. The workshop brought together sixty-four transportation professionals, regional and national stakeholders, and experts in climate change, the environment, planning, and energy to provide input on research priorities for the Center.
     
  • Greenhouse Gas Emissions From Road Transport. Summarizes OECD working group study of carbon dioxide emissions from highway transportation. Reviews recent trends in the U.S. and twelve other countries, identifies relevant policies and measures, identifies issues associated with assessment methods, and reviews outlook for future emissions as related to trends in population, economic growth, and fleet turnover. Presented January 8, 2001.
     
  • Transport-Relevant Policies and Measures: U.S. Experience. Discusses distinction between "best" and "relevant" policies, reviews broad U.S. goals for transportation, and identifies some U.S. policies that are relevant to transportation and climate change. Presented at UNFCCC Workshop on Best Practices in Policies and Measures, Copenhagen, April 11-13, 2000.
Last updated: Tuesday, May 1, 2018