Modelling urban transportation emissions: role of GIS

In the development of methodology that can assist the decision-making process for reducing vehicle emissions in urban areas, the benefit of using geographic information systems (GIS) in enhancing the reliability of data is indeed significant. There are other positive features that could be used to enhance analyses and to prepare information in support of decision-making. These include: visualization of analysis results, improved communication with decision-makers, new analytical tools for testing transport technology innovations and investigating travel behaviour. This paper reports the methodological framework that is required for analysing the emission implications of measures that are intended to reduce vehicle emissions in urban transportation. A case study of the National Capital Region (NCR) Canada is used for illustration purposes. The overall framework for urban transportation planning, including emissions estimation, is introduced. The role of GIS is highlighted in terms of enhancing the reliability of data. Methodologies are noted that serve as an interface between travel analysis and emissions estimation. An emissions calculator is described that enables the estimation of air quality pollutants and greenhouse gas emissions. Finally, results of selected scenarios are presented.