Framework for Integrating Traffic-Source Emission Estimates into Sustainability Analysis

Alleviating highway congestion and environmental impacts associated with vehicle travel is one of strategies to address issues related to transportation greenhouse gases and urban development sustainability. However, the challenge lies in quantifying and assessing the carbon footprint as a basis for the advanced planning and traffic control strategies. The worst case scenario may be identified by analyzing insightful interactions between travel demand due to adaptive changes in land use and social economy and the impact of transportation activities on road emission and air quality. This paper presents a framework to fill in the gap of tools and methodology through developing a Geographical Information System (GIS)-based Roadway Air Impact Analysis (RAIA) system, housed in the Scenario-Based Planning Support System (SB-PSS) system. The RAIA system is established through integrating travel forecasting, vehicle emission and vehicle powered energy consumption models with friendly-heuristic framework and data flows via input/output (I/O) interfaces. The air quality measures, such as Air Quality Index (AQI) and NAAQS (National and State of Ambient Air Quality Standards), are embedded into the RAIA system. Travel demand forecasting models estimate the trips based on land use adaptation and social economic fabric; microscopic traffic simulation model is used to assess the measures of effectiveness of traffic operation and control strategies; vehicle emission model estimates the emission factors due to transportation activities; and vehicle powered energy consumption model is used to estimate energy consumption. Within this ambiance, traffic-related emission and energy consumption demand will be projected based on various land-use and traffic management scenarios. Such an integration effort is expected to be beneficial to identifying strategic solutions to design and operate transportation systems in a way that meets transportation needs while protecting the environment and the health of all people, and provide supportive information for measuring and assessing sustainability and "greenness" of transportation and other urban infrastructure systems.