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The concept of automated cars is rapidly becoming a reality. Yet there has been very little analysis of the impacts of such developments on the performance of urban transport systems. These impacts are potentially complex. On the positive side, automation has the potential to increase road capacity, make driving available to more people, and reduce accidents and emissions. On the negative side, it could attract users away from public transport, walking and cycling, substantially increase traffic levels and stimulate urban sprawl. These impacts cannot currently be measured empirically and, by the time that they can, it will be too late to change the implementation model to rectify any resulting problems. Predictive assessments are therefore needed. This paper considers the possible impacts of automated vehicles, predicts their effects on the urban land use and transport system, and discusses the policy implications. We focus on automation of the car fleet, and do not consider the potential of automation of public transport or freight. We consider the literature on the range of attributes of automated vehicles which might affect transport and land use patterns, and suggest potential outcomes for each over the period to 2050. These include the proportion of automated vehicles in the car fleet, whether automated vehicles are privately purchased or publicly shared, the impacts on network capacity, the reduced need to pay for and walk from parking places, the potential reduction in the value of in-vehicle time and the potential use by current non-drivers. We represent these attributes in an expanded causal link diagram of the urban land use and transport system and import those causal links into the MARS system dynamics model. We determine from the literature a level for each attribute, and test the impacts in a set of ten scenarios using an updated MARS model of Leeds. Based on our input assumptions, we find that car-km in 2050 could be over 50% higher than in the business as usual scenario. Public transport use could fall by 18%, threatening accessibility for those dependent on it, while walking and cycling could fall by 13%, reducing their health benefits. Overall person-km would rise, suggesting a reduction in sustainability. A requirement that all automated cars are shared vehicles could reduce these adverse impacts somewhat, but the effects are sensitive to the charge per km. Our use of a single value for each attribute means that our analysis is exploratory, but the size of the resulting impacts demonstrates the importance of understanding the scale of systems response to each of the attributes which we have considered. It will be important to manage the way in which automated cars are introduced into urban areas, if they are not to lead to a worsening of the urban environment, accessibility and health. A requirement to make all such vehicles part of shared fleets offers one way forward, but more work is needed to understand the way in which use of such fleets should be charged. • We review the literature on the possible demand-side and supply-side impacts of autonomous automobiles on urban transport and land use under private and shared ownership, and on the likely scale of such impacts. • We enhance a System Dynamics Land Use – Transport Interaction Model, MARS, to reflect the causal effects of the majority of these impacts. • We apply the enhanced model to the city of Leeds, UK, to test the effects of each potential impact on its own and of all impacts combined, under both fully private and fully shared ownership. • We find a clear synergistic effect between the impacts, leading to considerably higher levels of automobile use under automation; we predict car-km to increase by 56% for private ownership and 41% under shared ownership by 2050 when compared with business as usual. Total person-km rise by 39% and 32% respectively, while use of public transport, walking and cycling fall, indicating a move to a less sustainable future. • We explore the impacts on land use, suggesting that, while private ownership will add to urban sprawl, shared ownership might have the opposite effect. We discuss the policy implications. [ABSTRACT FROM AUTHOR]

Abstract: Several studies have indicated that option generation – the development of a range of strategic policy options to tackle identified transport problems – is the weakest link in current transport planning practice. Local authorities all too often limit themselves to pre-conceived solutions, focus on supply-side rather than demand-side polices, and are unaware of the potential of novel solutions. This is even more the case for the development of packages of policy instruments, in which each can be expected to support the others by making it more effective or easier to implement. A decision-support tool, based on the transport policy knowledgebase, KonSULT, which generates possible policy packages, is described. The tool can operate in one of two ways: by taking a single user-specified policy instrument, and identifying the other policy instruments in KonSULT which might best support it; or by taking a user-specified shortlist of up to ten policy instruments, and identifying those combinations which might perform best in the specified context. In both cases the user specifies whether the emphasis should be on synergy or on the resolution of barriers. The best performing instruments are highlighted through a scoring system. The synergy scores were initially based on professional judgment. Subsequently, a sketch planning model was used to provide improved estimates for them. The resolution of barriers scores continue to be based on professional judgement. The paper describes the development of the tool and discusses the implications of the subsequent model-based analysis. It outlines future developments and reviews the role of such tools in policy formulation. [Copyright &y& Elsevier]

Abstract: While techniques for identifying urban transport problems, predicting the effects of possible solutions and appraising their performance are well developed, there is a significant gap in the decision-making chain relating to the generation of those possible solutions. A literature review has identified a number of option generation methods in other sectors, which are of potential application to transport. It categorises them into ‘inside the box’ methods, which are principally quantitative and draw on a pre-existing list of solutions, and ‘outside the box’ methods, which are more qualitative but potentially better able to generate wholly novel solutions. It also distinguishes between applications at the levels of formulation of an overall strategy and of detailed design of a particular scheme. An ‘inside the box’ method for strategy option generation has been developed building on the capabilities of an existing web-based knowledgebase, KonSULT. The design principles are described and potential further developments outlined. [Copyright &y& Elsevier]

Abstract: There is now an increased understanding of the need to design urban transport and land-use systems to be more sustainable, and of the policies which are needed to achieve this. However, work by the European Conference of Ministers of Transport has highlighted the institutional, acceptability, financial, information, regulatory and process barriers to implementing them. These barriers are evident in the UK, even though it has a particularly developed approach to local transport planning. As a contribution to overcoming them, a 4-year research programme has been conducted to develop decision-support tools for local government. The paper describes the international background to this research programme, its objectives and overall structure and its interaction with local authorities. The barriers to sustainability identified by the programme''s local authority partners are presented, the development of the selected products from the research programme is outlined and the challenges in transferring them into practice are discussed. [Copyright &y& Elsevier]

Abstract: Integration as a principle in urban transport policy is frequently advocated but rarely defined. We suggest a range of types of integration, and highlight the problems in developing an effective integrated strategy, given the number of variables involved. We argue that integration should be designed to serve agreed objectives of transport policy, rather than being an objective in its own right. We then consider the principles for designing an effective integrated strategy. We define the concept of synergy, which is often advocated as a benefit of integration, and discuss whether it, and other aggregation benefits short of true synergy, is achievable. We then consider the alternative approach of using integration to overcome barriers, an approach, which is likely to be in conflict with pursuit of synergy, but more likely to lead to readily implemented strategies. We then review a number of examples where these principles have been applied, and investigate them to assess whether synergy has been demonstrated. Generally we find little evidence of synergy in outcome indicators. We conclude with some more general guidance on approaches to integration. [Copyright &y& Elsevier]

The experience of traffic demand management policy in many cities shows that a single policy instrument has limited effect and may have side effects on other contemporaneous policies; therefore, formulating a policy mix is a more effective way to solve urban traffic problems. However, the bulk of previous literature has focused on the impact of single policy instruments, neglecting the growing interest in understanding the role played by the different combinations of policy instruments. Therefore, using a 6*3 matrix typology, this paper provides an empirical impact analysis of selected policy mixes in inducing sustainable travel behavior and reducing private car use. This study also designs orthogonal experiments and adopts stated preference questionnaires to analyze the main effects and full combined effects of packages of policy instruments through multinomial logit models. The results show that the effect of a policy mix is often not better than that of a single policy and demonstrate the need for careful systemic design. A balanced-designed policy mix can facilitate public transportation and help reduce traffic gridlock using a balanced combination of push, pull and systemic TDM policy instruments. • A 6*3 matrix typology has been proposed to get a more balanced classification of TDM policies. • Seven policy instruments were used to design the policy mix scenarios by the orthogonal experiment design. • The main and full combined effects of packages of policy instruments among seven kinds of travel modes are estimated. • Policy suggestions on how to use policy packages to encourage the choices of sustainable travel modes are provided. [ABSTRACT FROM AUTHOR]

• Urban areas are hot spots for exposure to traffic-related air pollution (TRAP). • A protocol is presented for our upcoming systematic evidence map (SEM). • We will identify urban-level policy interventions to reduce traffic emissions/TRAP. • We will explore and characterize the available evidence base. • An open access, interactive database will host extracted information. Cities are the world's engines of economic growth, innovation, and social change, but they are also hot spots for human exposure to air pollution, mainly originating from road traffic. As the urban population continues to grow, a greater quantity of people risk exposure to traffic-related air pollution (TRAP), and therefore also risk adverse health effects. In many cities, there is scope for further improvement in air quality through targeted urban policy interventions. The objective of this protocol is to detail the methods that will be used for a systematic evidence map (SEM) which will identify and characterize the evidence on policy interventions that can be implemented at the urban-level to reduce traffic emissions and/or TRAP from on-road mobile sources, thus reducing human exposures and adverse health impacts. Articles will be searched for and selected based on a predetermined search strategy and eligibility criteria. A variety of databases will be searched for relevant articles published in English between January 1, 2000 and June 1, 2020 to encompass the interdisciplinary nature of this SEM, and articles will be stored and screened using Rayyan QCRI. Predetermined study characteristics will be extracted and coded from included studies in a Microsoft Excel sheet, which will serve as an open access, interactive database, and two authors will review the coded data for consistency. The database will be queryable, and various interactive charts, graphs, and maps will be created using Tableau Public for data visualization. The results of the evidence mapping will be detailed via narrative summary. This protocol serves to increase transparency of the SEM methods and provides an example for researchers pursuing future SEMs. [ABSTRACT FROM AUTHOR]