Toward an urban transport sustainability index: an European comparison
Eur. Transp. Res. Rev.
Toward an urban transport sustainability index: an European comparison
Pietro Zito
Giuseppe Salvo
Introduction The aim of paper is to cluster policies of sustainable mobility in order to define an essential set of specific Transport Performance Indicators (TPI). TPIs are standardized measures suitable for analysis in order to appraise the feasibility of a transport policy or an infrastructural project. Data collection of TPIs is a crucial phase, but data detection and monitoring are not standardized at the city level. Thus, there is no a standard for data collection and storing, this aspect makes much difficult to compare different city contexts. This issue is critical and bounds the analysis of built scenarios. A standardized set of transport performance indicators becomes, hence, essential for monitoring the implemented policies. Methodology and results The paper answers to some of these questions, providing a specific set of sustainable and transport performance indicators to evaluate effects of policy measures. Furthermore, it shows a comparative analysis of different European cities in terms of development, sustainability and infrastructures, by using transport performance indicators. A Normalized Transport Sustainability Index has been built using identified TPIs, in order to measure and hence to compare the whole sustainability of adopted policies in different urban areas. The same NTSI allows to appraise the expected results and thus to tune the policy measures. Conclusion We can affirm that an high value of sustainability is associated, in general, to small-medium cities in term both population and urban area; nevertheless, for large cities, the adoption of policy measures, from a side, to control the urban sprawl, from the other side, to manage the urban transport demand with an adequate public transport development allows to achieve a more sustainable mobility.
Transport performance indicators; Transport sustainability index; Urban sustainable mobility
1 Introduction
In the last years, warnings were more frequently launched
by the scientific community about the actual use of energy
resources and their progressive exhaustion, the effects on
the environment caused by economic, social and industrial
choices, in particular in terms of pollution. In this case,
climate changes are among the most marked effects, often
perceived even by not expert citizens. Obviously, such
inputs must be taken into account by policy makers that
participate to the debate on concerted strategies and actions
in order to reduce GHG emissions.
From one side, the scientific community shows
hypothetical global scenarios that redesign a lifestyle of people
heavily conditioned by effects of climate change, whether
actions for CO2 emission reduction in atmosphere would be
put in force now; such actions will have to become more
drastic every time that delays on actions occur. Many of
such actions could heavily influence the lifestyle of
citizens, habits, up to change over time, on large scale,
the industrial, economic and social structure on which
world economy and the society are based. Nevertheless, the
scientific viewpoint suffers of uncertainty related to long
period forecasting of possible future scenarios, therefore
damage estimations are affected by uncertainty and
inaccuracy. From the other side, the task of policy maker is to
manage the community and activities related to it. Her/his
decisions are often related to short term and are strongly
influenced by social and economic context.
1.1 Review of literature
Nowadays there is however the awareness that only
technological changes and more efficiency on fuels and vehicles are
not enough to reach sustainable environmentally transport
targets required to stabilize the CO2 in atmosphere in next
future [
37
]. These targets will be reached whether marked
behavioral change in citizens related to travel choices occur.
The sustainable mobility approach requires actions to reduce
the need to travel (less trip; i.e. by ICT, internet shopping,
teleworking and so on), to encourage modal shift (i.e. by
transport policy measures), to reduce trip length (i.e. by land
use and urban planning) and to encourage greater efficiency
in the transport system [
3
].
Many other studies confirm abovementioned statement.
Shiftan et al. [
33
] identified policies for a sustainable
transport system in Tel-Aviv Metropolitan Area by
scenarios and Delphi expert based survey. Findings in desired
scenario were a strong development of public transport
and a coordination between spatial development and
transport system, high parking fees, congestion pricing
and maintaining the functional role of Central Business
District Area. Whereas Rajan [
30
] pointed out that in
order to meet stringent emission targets technology and
pricing policies may have to be supplemented by
strategies to change life-styles and land uses in ways that
effectively reduce car dependence. Akerman (...truncated)