It is well known that economic growth is highly significant for transport growth. The hypothesis of the project is that a number of structural factors are determining the growth in transport as well as in the economy. Therefore it is necessary to go beyond the economic growth and into these structural factors to be able to handle the challenges of the transport growth. In this we follow the European Environment Agency (2008) that points to the need to expand the scope of policy and go beyond the transport sector itself to address transport demand where it originates. We have identified four structural factors behind the growth; factors that are also themselves influenced by the demand and growth. The two most basic ones are technological development and demography / socioeconomy / culture. Two other structural factors are more integrated in the economy and growth; that is globalisation leading to increasing long distance travel and transport, and urban structure, which is important for daily travel and transport.
While technological innovations might be able to reduce the problem in the very long run we anticipate that this is not possible in the short run. So far, advances in transport technologies have led to improved energy efficiency and reduced carbon intensity of fuels. On the other hand improved transport technology has been offset by a growing role of high speed and a steady increase in travel and commuting distances, more leisure trips and a demand for more powerful and heavier vehicles. But these effects of technological development are well known and studied so it is not the aim of this project to go deeper into this topic. We will concentrate on demography, the transport effect of globalisation, and on urban structure.
Better transport infrastructure linking markets has made it possible to exploit economies of scale, which in itself has contributed substantially to the growth in transport (Deakin, 2006). However, the potential of exploiting economies of scale and the increased specialisation worldwide are also important drivers of globalisation and economic growth. Rising incomes, globalisation, increasing leisure time, and earlier retirement make it possible for people to spend more time on leisure trips (Mokhtarian and Salomon, 2001) along with sharply falling costs of long distance transport, due to e.g. liberalisation and increased competition in air and other transport services. So far most studies of passenger transport have concentrated on shorter daily travel and little is known about long distance trips. However, long distance trips account for a significant and increasing part of transport, for passengers as well as for freight (Environment Agency, 2008), and thus for the negative externalities associated with transport. In this light, the lack of knowledge about long distance passenger and freight transport and the exact effect of the anticipated drivers is an increasing problem.
Freight traffic is increasing, but its actual composition and the relation between individual trips and different modes is not very well known. An increased understanding of these relationships can help us identifying excessive transport and make suggestions for policies aimed at increasing the efficiency of the freight transport system.
Socioeconomy is well known to be important for the transport behaviour of individuals. Therefore, demography can explain many changes and fluctuations of the national transport. Similarly, the cultural differences and traditional ways of using transport affect the total national transport. It is therefore important to be aware of the quality and quantity of such changes to be able to forecast future transport trends (Siu et al. 1995). In Denmark, as well as in many other western countries, we see especially challenges with the ageing of the post war baby-boom generation and their influence on the total transport demand (Rosenbloom, 2001; OECD, 2000). The young generation is another challenge as their transport behaviour related to the former generations might indicate changes in the behaviour of the future populations.
Research into the importance of urban structure for transport in Denmark and Europe has shown that the location of residences (i.e. Nielsen, 2002, Næss, 2006a) is an important driver for transport growth along with urban sprawl. International literature finds that the urban form and public transit supply do affect the travel demand (Bento et. al. 2005, Guiliano and Dargay 2006). Density and high quality public transport reduce car traffic and CO2 emissions. Therefore, the planning process might be of significant importance for the capacity to address the problem of future transport growth. However, as the relationship between urban structure and travel is still changing due to reduced distance decay, and as the effect of localisation of workplaces is more ambiguous (Christensen & Fosgerau, 2002) and as the physical mobility of labour and workplaces is important for the productivity and economic growth, this question is not answered trivially.