Transport demand is a complex phenomenon driven by a number of different factors that jointly make it difficult to provide well consolidated predictions of the far future, beyond the most aggregate level.
Analysis that take into account spatial and socio-economic context is needed to be able to foresee the effects of measures to influence transport demand, in regard to factors such as distance, volume and modal split.
The project investigated - for the empirical context of Denmark - key driving forces behind transport growth, as well as the notion of limits to mobility, arising out of system interactions or set by external policy ambitions.
To summarize some of the key findings in the study which lead in increased travel demand we found that in Denmark:
- Daily travel distances depend on regional centrality as well as more local conditions such as population density and access to retail and service nodes, this strengthen the case that urban form and location effects matter for transport demand and mobility patterns.
- Together with centrality still attracting most of the movement in Zealand, over time urban growth has reshaped the regional landscape into a connection of functionally of integrated urban regions, with spatial separation between the nodes and a high degree of ‘balance’ in the East Jutland region this means that not a single city is highly dominant/considerably larger than others.
- This is partly a result of the distribution of commuting and population in the region over time growing more equal, dispersing regional commuting in a larger and more diverse space where especially the increase in commuting between remote origins and destinations pulls the average and aggregate travel demand up.
- The findings that increasing commuting distances are compensated economically by the employers could potentially be a factor that has played a role to incentivise the progressive dispersion of jobs.
- The overtime distribution of population into polycentric, functionally integrated and accessible but separated nodes can be paralleled with the trends observed amongst baby-boomers who significantly engage in daily car use while they are still working and with retirement become more active in their leisure time, potentially contributing as well to the overall increase in long distance travel. Still, the baby-boomer's mileage is reduced with increasing age and after the initial years of retirement. Geographically, they are most likely to prefer living in sub-centres with good accessibility to central places, which increases their dependency on car mobility to meet their travel needs.