Sustainable Transport and Quality of Life

Automobile use has greatly increased during the last few decades. The number of passenger kilometers by private car per capita increased by 90 percent in Western Europe and 13 percent in the US between 1970 and 1990. In 1990, the average number of passenger kilometers travelled by private car in the US (18,650 km) was more than double the Western European figure (8710 km; OECD, 1996). The number of motorised vehicles in the world grew by about 600million between 1950 and 1990. Of the 675million motorised vehicles in 1990, approximately 80 percent were for passenger transport. However, the number of people in the world who do not own a car increased even more in this period, by over 2 billion (Adams, 1999; OECD, 1996). On a typical day in 1998, 75 percent of the adult population of Canada went somewhere in a car, up from 70 percent in 1986 (Clark, 2000). In the Netherlands, the number of car trips per person per day increased by 16 percent, while the number of kilometers driven by car per day increased by 31 percent between 1985 and 1998 (Steg & Kalfs, 2000). Of further concern, drivers seem to expect they will take far fewer trips than they actually do. When asked to prospectively estimate how many trips they would take during the next week, Swedish drivers took 80 percent more trips than they expected to (Jakobsson, 2004). The increasing number of cars and their daily use causes various problems (e.g., OECD, 1996; see also http://home.connection.com/Bregan/carcosts.htm for Canadian data and http://www.rivm.nl/milieu/ for Dutch data). Many have stressed that the current transportation system is not sustainable (e.g., OECD, 1996). Various strategies have been proposed to achieve a more sustainable transport system, ranging from behavioural to technological changes. Behavioural strategies are aimed at reducing the level of car use, for example by shifting to less-polluting modes of transport, changing destination choices, combining trips, encouraging car sharing 1