Transportation and the Environment : A Review of Empirical Literature

In urban areas around the world, increasing motorization and growing travel demand make theurban transportation sector an ever-greater contributor to local air pollution and greenhouse gas emissions. Thesituation is particularly acute in developing countries, where growing metropolitan regions suffer some of theworld’s highest levels of air pollution. Policies that seek to develop and manage this transportation sector—to meetrising demand linked to economic growth and safeguard the environment and human health—have had strikingly differentresults, with some inadvertently exacerbating the traffic and pollution they seek to mitigate. This paper provides anoverview of the findings of the recent literature on the impacts of a host of urban transportation policies used indeveloped and developing country settings. The paper identifies research challenges and future areas of study oftransportation policies, which can have important, long-lasting impacts on urban life and global climate change.