The chapter examines how transport affects the environment; how its impact can be quantified in economic terms; and how economic incentives can be used to reduce the environmental cost of transport, as well as addressing other externalities associated particularly with car use, such as congestion.
The environmental impacts of transport “Transportation services are essential component of economic activity, and are one key to its growth. Transportation has a number of environmental side effects that people dislike. Through the emission of pollutants by cars, lorries, buses, trains, and airplanes; through land-take, for example for new airports and new roads and; increase in noise levels. Economics can help us to quantify how bad these side-effects are, and can also help us design for reducing them.”
Pollution emissions “Emissions can be categorized into three broad types according to their effects. First, local pollutants. City traffic is a significant source of pollutants. Increase in those pollutants is linked to lower local air-quality and increase in illnesses. The second effect is regional. Acid rain has been blamed for water pollution and fish death. Transport is a major source of two of the constituents of acid rain. Finally transport is a significant net contributor to emissions of greenhouse gases.”
Land use “Building roads and airports imposes environmental costs, these include: reductions in landscape quality; loss of wildlife habitat; islanding effects, whereby movement corridors for wildlife are disrupted; and loss of cultural heritage sites, such as when new roads are built over archaeological sites.”
Noise “As traffic movements increase, so do noise levels. Noise impacts are usually measured as a weighted decibel, DbA, a scale which approximates the sensitivity of the human ear.”
Valuing the environmental impacts of transport “Transport has the three main environmental impacts: on air