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OCR for page 141
141 CHAPTER 5 Recommended Research Areas This chapter provides five recommended areas for research In addition, nationwide GHG emissions are calculated by that offer great promise for improving freight emissions EPA in the Inventory of U.S. Greenhouse Gas Emissions and Sinks estimates. Although these five research statements are mode- (the EPA GHG Inventory) annually. (1) This study allocates specific, the link between modes can be addressed with the GHG emissions to each sector of the economy, including implementation of the Conceptual Model. transportation, and within the transportation sector allocates Each of these areas will improve the Conceptual Model and emissions to each transportation mode, including on-road and modeling of these modes in general. The descriptions of these nonroad vehicles, locomotives, aircraft, and marine vessels. research areas have been written as research statements with Additionally, for several modes including on-road vehicles, sections describing background, objectives, description of tasks, the GHG Inventory further divides emissions by vehicle type. and funding requirements. This will provide the basis for The allocations are based on share of fuel consumption and NCFRP to develop statements of work and requests for pro- fuel type. posals for future work. For both the NEI and the GHG Inventory, the method- ology used to allocate emissions varies by mode, depending on available data sources. In some modes, such as rail, the 5.1 Improving the Allocation of NEI uses a "top-down" methodology, in which national- National Transportation Emissions level fuel consumption data are allocated to specific regions and modes, in proportion to a measure of activity level. Background Calculations for other modes, such as on-road and non- The transportation sector accounts for a large portion of road, rely on a "bottom-up" methodology, in which activity the nation's emissions inventory, resulting in significant data reported on the county level are aggregated and modeled local health and public welfare impacts as well as nation- using the National Mobile Emissions Model (NMIM), with wide greenhouse gas emissions (GHGs). These emissions resulting emissions allocated to each region. The EPA GHG are the subject of public policy at the national, state, and local Inventory methodology uses both top-down and bottom-up levels, in which regulatory agencies and industry organiza- approaches simultaneously, in which a top-down calcula- tions work together to minimize transportation emissions tion of fuel consumption by sector and mode based on fuel in a cost-effective manner. Calculations of both the current statistics is reconciled with a bottom-up modal analysis of emissions impacts and the benefits of mitigation strategies fuel consumption by industry activity measures. Although rely on the accurate allocation of national emissions esti- the NEI focuses on regional allocation and the EPA GHG mates to individual geographic regions, transportation modes, Inventory focuses on modal allocation, the accuracy of and vehicle types. both methodologies depends on the quality of regional and On the national scale, criteria air pollutant (CAP) and activity data and the allocation method used, which vary hazardous air pollutant (HAP) emissions are calculated by across modes. the EPA in the National Emissions Inventory (the NEI), (2) There are both known and unknown limitations to the data which is completed every 3 years. The NEI provides emissions used for regional and modal allocation, leading to uncertainty data on the county level by SCC, representing the on-road, in the resulting emissions allocations. Research is needed nonroad, locomotive, marine, and air transportation modes, to determine the sources and magnitude of uncertainty in as well as subcategories within each mode. emissions allocation, and to develop more accurate methods

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142 and data sources for allocating national transportation emis- Task 1: Conduct Kick-Off Call sions by region. Conduct a conference call with the panel 30 days after con- This research statement builds on prior work completed tract initiation to discuss the revised work plan developed in by the Transportation Research Board and other regulatory response to the panel review of the research plan in the agency's agencies. The analysis of data sources continues research com- original proposal. pleted by transportation sector (such as this effort) and mode (ACRP Report 11: Guidebook on Preparing Airport Greenhouse Gas Emissions Inventories). (37) Task 2: Describe the Current Methodologies EPA has analyzed transportation emissions in depth, both in terms of GHG inventories (3) and in terms of evaluating Describe the current methodologies used to allocate national uncertainty in emissions results. (195) emissions to regions and transportation modes. Identify sources The subjects and results of this research may impact agencies of uncertainty in data sources and methodologies used in at the national, state, and regional level. The NEI is conducted allocation. by the EPA Office of Air Planning and Standards. The GHG Inventory is conducted by the EPA Climate Change Division Task 3: Analyze the Limitations of the Office of Atmospheric Programs. Emissions of CAPs and of Current Methodologies hazardous air pollutants (HAPs) within transportation modes are regulated by EPA in nonattainment areas (NAAs) and in Building on Task 2, describe the limitations of current allo- state implementation plans. Finally, transportation-related cation methods, and evaluate the magnitude of uncertainty GHG emissions are under analysis by several state DOTs either both in the data and methodologies used to allocate emissions for inventory or policy purposes. to the regional level. Submit an interim report to the panel describing the results of Tasks 2 and 3. Objectives Task 4: Identify Options for Reducing Uncertainty The objective of this research is to analyze current methods and data sources for allocating national CAP, HAP, and GHG Identify and evaluate options for reducing uncertainty and emissions by region and mode, and to identify opportunities increasing accuracy in regional and modal emissions estimates for improving the accuracy of such allocations. To thoroughly by pollutant and transportation mode. The analysis of options evaluate the issues involved, this research will include a review should include the extent of data or modeling requirements, the of sources of uncertainty in the data and methodologies used, ease or complexity of data collection, and any institutional an evaluation of the magnitude of uncertainty in regional or industry barriers to implementing the proposed strategy. emissions inventories, and an identification of improvements Recommend opportunities for strategy implementation that to minimize uncertainties in regional emissions estimates. would reduce uncertainty in regional emissions estimates con- Finally, since the GHG Inventory allocates emissions by mode sidering budget and time constraints. but not region, the research will analyze potential methods to allocate regional GHG emissions. The research and results Task 5: Analyze Allocation Strategies should span pollutant types including CAP, HAP, and GHG, as well as transportation modes including on-road, nonroad, Analyze strategies for extending the allocation of GHG locomotive, marine, and aircraft. emissions to the state and regional level, with consideration of accuracy and implementation issues. Description of Tasks Task 6: Prepare Final Report Task descriptions are intended to provide a framework for conducting the research. NCFRP is seeking the insights of Prepare a final report providing the results of the entire proposers on how best to achieve the research objective. research effort. Proposers are expected to describe research plans that can realistically be accomplished within the constraints of available Funding Requirements funds and contract time. Proposals must present the proposers' current thinking in sufficient detail to demonstrate their under- A funding level of $200,000 is allocated to this research. standing of the issues and the soundness of their approach to The contract will be completed within 12 months of accept- meeting the research objective. ance of proposal, including 1 month for NCFRP review and