Green Infrastructure: The Effects of Urban Rail Transit on Air Quality

Alex Whalley, Assistant Professor of Economics at the University of California, Merced, delivers a lecture on Tuesday, July 19, 2011 from 11:00am to 12:00 noon in Room 103 of the John H. Daniels Faculty of Architecture, Landscape and Design at the University of Toronto, located at 230 College Street. All are welcome to attend. The transportation sector is a major source of air pollution worldwide, yet little is known about the effects of transportation infrastructure on air quality. In this presentation, the effects of one major type of transportation infrastructure – urban rail transit – on air quality is measured. The approach uses the sharp discontinuity in transit utilization on the opening day of a completely new rail transit system in Taipei, Taiwan to identify the air quality effects of rail transit infrastructure. Using hourly air quality data from Taiwan, there are three central findings. First, the opening of the Metro reduced air pollution from one key tailpipe pollutant, carbon monoxide, by 5 to 15 percent. Second, little evidence is found that the opening of the Metro affected ground level ozone pollution. Third, there is little evidence to suggest that automobile travellers adjusted their time or route of travel to the availability of rail transit. These findings shed new light on the determinants of air quality, and suggest that environmental impacts are important components of the social value of transportation infrastructure.

Alexander Whalley is an Assistant Professor of Economics at the University of California, Merced. Alex’s research has focused on the causes and consequences of government policies at the local level as well as the economics of higher education and innovation. Recent research has explored the impact of public transport infrastructure on air pollution, universities on local economic growth, housing bubbles on the size of city governments, and city governance structures on the costs of public financing. His research has received financial support from the National Science Foundation and the National Bureau of Economic Research. Whalley graduated from the University of Western Ontario in 1998, earned an MA in Economics from the University of British Columbia in 1999, and completed his doctorate in Economics from the University of Maryland, College Park in 2006.    URL: