Car Dependency Research Articles

If a Colleague Asks: “Will my Innovation Have Unintended Consequences?”

We love to talk about the unintended consequences of others’ technological innovations. We document the air pollution and traffic congestion accompanying automobile dependence, the surrender of personal privacy in order to gain online convenience, and the political violence abetted by social media algorithms optimized to generate advertising revenue.

The carbon ‘carprint’ of urbanization: New evidence from French cities

This paper investigates the causal impact of city shape on car use and emissions within French metropolitan areas. We in particular analyze the influence of a novel indicator of urban geometry that captures differences in the built environment likely to nurture or alleviate car dependence. Individual data allow us to separate the effects of urban geometry and households' spatial sorting, while historical and geological instruments help tackling ‘endogeneous density’ issues. Cities with a more compact, fractal and diverse spatial layout have lower car emissions per household. Urban geometry drives a bell-shaped relationship between city size and the ‘carprint’ of households: small cities compensate for their lack of Density or Diversity by an environmentally-friendly geometric Design, whereas medium cities exhibit heavier driving footprints.

Social sustainability of regional transportation: An assessment framework with application to EU road transport

The assessment of transportation social sustainability appeals to many scholars as an essential issue but imposes a risk of selecting inadequate factors and methods to measure social phenomena. In this study, based on an extensive review, we identify the measurable key social indicators (instead of the economic or environmental factors commonly used) and propose a comprehensive evaluation framework for relative performance analysis of social sustainability in the regional context. This work is the first attempt to assess regional social sustainability of transport explicitly utilizing a multi-output performance measure. We use Shannon entropy to combine the results of selected data envelopment analysis (DEA) models into a unified social sustainability performance score. The method is applied to regional road transport in the European Union (EU) member states for the period 2004–2017. The empirical section explores individual profiles of EU countries, compares the states grouped into two clusters of old (EU-15) and new (EU-13) EU members, and examines their social sustainability performance over time. The analysis suggests that considering only social factors in the measurement eliminates the bias resulting from the inclusion of economic factors. As a result, our method prevents inaccurate inflation of the scores of more economically advanced countries. The findings also draw attention to the car dependence problem associated with high motorization rates in affluent EU-15 states. The study confirms the capacity of the proposed DEA-based framework to serve as an adequate tool for measuring the social sustainability of transport, which can support policymakers by providing useful benchmarks employing social factors.

Re-designing America's suburbs for the age of climate change and pandemics.

The USA is the leading emitter of greenhouse gases among the developed countries, in part because it is the only developed country with more of its population in suburbs than in cities. Cities produce less greenhouse gas emissions per capita than suburbs. Meanwhile, the US and the world have been wrestling with the public health emergency of the COVID-19 pandemic. But as US cities recover from the pandemic, they are unlikely to add more population than their suburbs because of changes in favor of working from home, online shopping, and the search for more affordable housing and green space, as well as concerns about population density and contagious diseases. So, the challenge is how to design and redevelop suburbs to make them more environmentally, socially, and economically sustainable to address both climate change and the threat of future pandemics. A sustainable suburb scenario offers an alternative to the sprawling development, separation of land uses and income classes, and automobile dependence that characterizes the typical American suburban landscape. This essay reviews the literature on re-designing suburbs and describes and evaluates both a business-as-usual suburb scenario and a sustainable suburb scenario. Though challenges exist, sustainable suburbs will be needed in order to reduce US greenhouse gas emissions, to achieve greater resilience in adapting to the effects of climate change, and to guard against future pandemics while providing economic opportunities and greater equity over the long run.

Are multimodal travellers going to abandon sustainable travel for L3 automated vehicles?

Reducing car dependency supports the creation of a more sustainable transport system. However, automated vehicles (AVs) are predicted to increase the attractiveness of car travel and decrease the use of public transport and active travel. This current study explored how travellers’ intention to use AVs and their current travel behaviour influence their expectations of how they will use public transport and active travel, once conditionally automated (SAE L3) vehicles (L3 AVs) are available.Survey data (collected during the EU H2020 L3Pilot project) from among current car users from eight European countries (n = 9118) was used. Respondents were asked about their current travel mode usage, intention to use L3 AVs, and expected changes in the use of public transport and active travel once L3 AVs are available. The respondents were divided into nine user segments based on their level of intention to use L3 AVs and multimodality.Most respondents did not foresee changes in their use of public transport (62%) or active travel (67%). A higher intention to use L3 AVs increased the probability of a traveller expecting to decrease their use of public transport and, to a lesser extent, active travel. Multimodal travellers used public transport and active travel regularly and were also more likely to see a change, either up or down, in their use of public transport and active travel. The results suggest that L3 AVs may pose a challenge to the sustainability by encouraging current users of public transport and active travel to switch to personal AVs.

How Urban Planning Impacts Latino Vendor Markets

Flea markets and swap meets, classified here as Latino vendor markets (LVM), operate as social support systems for their communities. LVM are hubs of economic opportunity for business owners, yet they currently lack support from the field of urban planning. This paper explores four LVM case studies in California and Texas. A mixed-methods approach was used which included site observations, geospatial analysis and surveys with over 200 vendors, customers, and market managers to explore the urban linkages of LVM. Key findings include that LVM are at risk of potential redevelopment; they lack accessibility and perpetuate car dependence; yet there are opportunities to support LVM through planning tools such as improvement districts. They present lessons for exploring the links between the public and private sectors in reinforcing the social, economic and political benefit of marketplaces in the city.

Design Strategies of Life Outside and Life Inside for Livable Multi-family Housing Environment

This paper discusses the issue related to social life within the context of a neighbourhood. It takes on the case study of multi-family housing, which its urban forms are generally monofunctional, stand-alone, large scale, spread out and car dependency. This type of urban form may cause inclusivity and isolation to its context and problems in social interactions within its neighbourhood. This study examined the concept of life outside and life inside in multi-family housing design to create a more livable housing environment. The life outside concept aims to create a human-oriented neighbourhood by directing daily human activity towards outdoor space, through the integration of proximity, density, dan diversity. While the life inside concept aims to allow, residents to socialize with others through the design of a high probability of encounter zones in the building. Based on the observation at a multifamily housing complex at Rainbow Springs, Tangerang, this study proposed design criteria and strategies for a livable multi-family housing environment within the neighbourhood and inside the building itself. This study implies that integration between site planning and building design should be taken into consideration to form a livable neighbourhood.

Analysis of travel mode choice and trip chain pattern relationships based on multi-day GPS data: A case study in Shanghai, China

As the propensity to link multiple intermediate stops in a trip chain (a sequence of journeys that starts and ends at home, includes visiting one or more locations) is more prevalent, the relationship between travel mode choice and trip chain pattern aroused the attention of academics. This paper examines two distinct structures to identify the decision process of travelers between travel mode choice and trip chain pattern: one structure in which trip chain pattern organization precedes travel mode choice, another structure in which travel mode choice decision precedes the organization of trip chain pattern. To accommodate multi-day behavioral variability and unobserved heterogeneity in personal characteristics ignored by traditional travel surveys, multi-day GPS data collected in Shanghai is employed to estimate these two structures within Nested Logit (NL) model. The Monte Carlo (MC) method simulates the switch of trip-chaining and mode choice under possible Transportation Demand Management (TDM) strategies based on estimation results. The findings of this study are as follows: (1) trip chain pattern decision precedes travel mode choice, which means trip-chaining is organized first and affects travel mode choice; (2) complex trip chain is related to higher automobile dependency, and it is a barrier to the tendency to adopt public transit; (3) people who generally travel by automobiles might switch to public transit when private cars are unavailable, and an increase in household bicycle ownership enhances competition between the bicycle and public transit which leads people to turn to cycling. These findings help implement TDM strategies to develop sustainable transportation systems and optimize the urban trip structure.

What role does free-floating car sharing play for changes in car ownership? Evidence from longitudinal survey data and population segments in Copenhagen

Free-floating car sharing (FFCS) offers greater flexibility than station-based car sharing but seems to affect car ownership less. This study looks into characteristics of people who changed or did not change car ownership over time and how an increase or decrease relates to FFCS membership, demographic and attitudinal factors. The study is based on FFCS users (n = 776) and non-users (n = 720) in Copenhagen surveyed two times within a 2.5-year period. Five population segments were created: car dependents, car avoiders, and car limiters who showed constant but different levels of car ownership; car aspirers who increased, and car sellers who decreased car ownership over time. The segments' profiles range from car dependents who show high affective car motives, high perceived mobility necessities and car dependency at the one end, and car avoiders who seem more driven by environmental norms and an instrumental relation to the car, at the other end of the scale. A multinomial regression predicting whether car owners increased or decreased the number of cars in the household during the project period found a positive effect of FFCS membership for decreasing car ownership. However, the effect was no longer significant when adding the intention to reduce car ownership at the time of the first survey. Main factors that remained significant for changed car ownership included a change in household composition, access to a private parking space and the initial number of cars in the household. The paper discusses strategies to increase the contribution of FFCS to car ownership reduction.

Electric bicycles and cargo bikes—Tools for parents to keep on biking in auto-centric communities? Findings from a US metropolitan area

Despite a marked increase in electric bicycle (e-bike) research, few studies have looked at how parents or caretakers use e-bikes specifically to transport children. This is a missed opportunity, as parenthood often results in increased auto dependence. Getting more parents or caretakers on e-bikes or to continue biking would align with policies aimed at decreasing automobile dependence and increasing physical activity. This paper presents findings from in-depth interviews aimed to understand how families used e-bikes daily to transport their children, what factors motivated them to start, and what encourages them to continue this practice. Twenty parents and caretakers in the San Francisco Bay Area of the United States participated in the interviews which resulted in the following findings: e-bikes increased accessibility to communities, provided opportunities for greater physical activity, substituted for car trips, and allowed for more family quality time with the added benefit of reducing stress. The interviews also uncovered barriers like price and social stigmas, especially among less experienced or less committed cyclists. Finally, context matters. Bike infrastructure, local policies, and a supportive biking culture make it more likely that barriers would be overcome. More research is needed to understand the prevalence of family use of e-bikes, particularly in places with less supportive bike infrastructure and culture.

Monitoring Urban Sprawl Using Time-Series Data: Famagusta Region of Northern Cyprus

Monitoring urban sprawl is a controversial topic among scholars. Many studies have tried to employ various methods for monitoring urban sprawl in cases of North American and Northern and Western European cities. Although numerous methods have been applied with great success in various developed countries, they are predominantly impractical for cases of developing Mediterranean European cities that lack reliable census data. Besides, the complexity of the methods made them difficult to perform in underfunded situations. Therefore, this study aims to develop a new multidimensional method that researchers and planners can apply readily in developing Mediterranean European cities. The new method was tested in the Famagusta region of Northern Cyprus, which has been experiencing unplanned growth for the past half-century. In support of this proposal, a detailed review of the existing literature is presented with an emphasis on urban sprawl characteristics. Four characteristics were chosen to monitor urban sprawl’s development in the Famagusta region. The method was structured based on a time-series (2001, 2006, 2011, and 2016) dataset that used remote sensing data and geographical information systems to monitor the urban sprawl. Based on the findings, the Famagusta region experienced rapid growth during the last 15 years. The lack of a masterplan resulted in the uncontrolled expansion of the city in the exurban areas. The development configuration was polycentric and linear in form with single-use composition. Together, the expansion and configuration manifested as more built-up area, scattered development, and increased automobile dependency.

Road network vulnerability and city-level characteristics: A nationwide comparative analysis of Japanese cities

Climate change is making our cities more vulnerable, increasing the needs for further policy actions to make them more resilient. In particular, the transport network is critical in the first phase of disaster response. This study presents the epirical findings of a large scale, nationwide analysis of the road network vulnerability in 69 Japanese cities. We (1) identify the level of network efficiency using topological elements in its undisturbed normal state; (2) evaluate the level of network robustness under different random and targeted attack scenarios; and (3) analyze the relationship of the identified network efficiency and robustness indicators with city-level characteristics. The main findings include: (1) cities with a higher population and a higher infrastructure investment tend to be more robust under random attacks; (2) larger cities tend to be less robust to targeted attacks, presumably due to their high agglomeration of urban functions; (3) car dependency tends to make cities more vulnerable toward random attacks and less vulnerable toward targeted attacks as it indicates a weaker concentration in urban functions; and (4) a high modal share for trains tends to make cities less vulnerable toward random events as it indicates a high agglomeration of urban functions. These findings will help policymakers to prioritize their budget allocations to improve nationwide disaster resilience.

Commuting mode share and workplace-based public transport services: An equity perspective

Forced car ownership, defined as owning a car despite having limited economic resources, is an increasingly prevalent issue that places low-income households under significant economic stress. This is largely due to the car-oriented development that has prevailed in the last decades in most metropolitan regions in North America and many other parts of the world. Knowing that the desire to access employment opportunities, combined with the lack of adequate transport alternatives, is a major factor contributing to the acquisition of a car among low-income households, this research investigates the use of cars to access employment locations from a social equity perspective. More specifically, this study seeks to understand the relationship between public transport services at the workplace and commuting mode share, by combining detailed workplace-based census data with public transport schedule data. The spatial dispersion of low-income employment across the territory is first assessed. A linear regression model is then conducted to examine the relationship between mode share and public transport services, while controlling for the socio-economic characteristics of the commuters working in these areas. Interactions terms are included to assess the differentiated impact of service frequency across income groups. The results show that employment locations with high shares of low-income (LI) workers are spatially dispersed across the territory and are not, as a general trend, favoured in terms of public transport provision. The results of the linear regression model demonstrate that, in addition to the proximity of a metro station, frequent bus services are strongly associated with a decrease of the modal share of car, especially in areas that concentrate larger shares of LI workers. This result, combined with the spatial dispersion of LI jobs, points towards the improvement of bus services as a key strategy to better serve LI jobs and thereby reduce car use and dependency among LI workers. More specifically, one potential avenue would be to explore the development of rapid bus corridors along commercial streets. Taken together, the results of the study shed light on the importance and possible equity benefits of transport policies aiming at developing frequent bus services to support lower use of cars among LI workers. By using census data aggregated at the work locations instead of at the place of residence, this study complements the research on travel behaviour and equity, which is typically based on the residential location of different socio-economic groups. The findings of this study are of relevance to researchers and policymakers wishing to explore potential levers to reduce car use among low-income households.

Growth over resilience: how Canadian municipalities frame the challenge of reducing carbon emissions

ABSTRACT In response to anthropogenic climate change, many governments are adopting policies to reduce carbon emissions. In Canada, federal and provincial governments have implemented carbon pricing. One of the effects of putting a price on carbon is increasing the cost of using private vehicles, which may reduce mobility and increase the risk of social exclusion, especially in contexts where car dependence is high. In this article, we analyse how municipal governments in Canada frame the challenges of climate change and reducing emissions, and examine whether they link these challenges to issues of mobility and social exclusion. Focusing on policies from four of Canada's largest cities – Calgary, Edmonton, Winnipeg and Vancouver – we identify four main frames used in planning documents: “the Growing City”, “If You Build It, They Will Come”, “Better City for All”, and “the Resilient City”. The Growing City frame is used to support status quo urban development, with climate mitigation options (including sustainable travel modes) optionally included for more concerned residents. This is the dominant frame in Calgary, Edmonton, and Winnipeg. Conversely, Vancouver uses the Resilient City frame to indicate that climate mitigation and adaption strategies are essential, and all citizens must be prepared for change. Vancouver presents changes to mobility as necessary for all, rather than an option for some. Social exclusion is not explicitly addressed in the frames, though it is presented as a reason to support building alternative transportation or more public spaces. Social exclusion receives little consideration as a potential consequence of climate mitigation policies.

Transport accessibility, residential satisfaction, and moving intention in a context of limited travel mode choice

Abstract This paper examines the effects of transport accessibility on residential satisfaction and moving intention when travel mode choice is limited. It uses the case of Yangon City in Myanmar, where bus is the dominant transport mode, automobile dependence is low, and the use of two-wheel vehicle is restricted in some areas of the city. These characteristics altogether indicate that the potential bias arising from the unobserved differences in people’s travel mode preferences can be minimized. Based on a sample of about 5,200 residents living close to bus stops, structural equation modeling is used to test the effects of objective and subjective measures of bus stop accessibility on residential satisfaction and moving intention. The results show that high perceived bus stop accessibility—not short distance between the residence and the nearest bus stop—is associated with high residential satisfaction, and neither measures of bus stop accessibility is associated with moving intention. These findings indicate that the perception of bus stop accessibility matters for residential satisfaction rather than the actual distance between the residence and the nearest bus stop, and the low satisfaction with bus stop accessibility is not expected to induce households to consider moving to a new residence or location. The actual distance between the residence and the nearest bus stop has the strongest influence on perceived bus stop accessibility, followed by the satisfaction with neighborhood’s safety and security, holding household characteristics constant. From a policy perspective, the findings underscore the relevance of including subjective measures of accessibility in designing or improving the accessibility of transport systems. To aid planning, there is a need to explore the objective factors that underlie people’s satisfaction with transport accessibility. Moreover, an integrated housing and transport policy could bring significant gains to residents, as desirable neighborhood features are associated with not only high perceived bus stop accessibility but also high residential satisfaction and low moving intention.

Exploring sustainable transportation development in Penang: stakeholders’ perspectives of the Penang Transport Master Plan

Transportation is associated with all aspects of the nation’s growth. Nowadays, sustainability is one of the primary goals of many urban transportation systems. Over the past, many innovative initiatives have been undertaken to achieve a safe, efficient, and sustainable transport system. Besides, natural environment, social wellbeing, and economic prosperity depend on sound transportation systems. In Malaysia, Penang is well-known as an industrial and medical hub. In recent years, the state has experienced rapid economic growth. However, without proper development planning for the transportation system and infrastructure, the growth for sustainable development will be jeopardised. Heavy congestions due to increasing car dependency lead to psychological stress for the travellers. There are limited studies on sustainable transportations in Penang. Therefore, this study will explore the current transportation system in Penang, including the Penang Transport Master Plan. To address the aim of the research, we adopt an inductive cross-organisational semi-structured interview to explore the current level of sustainability within Penang transportation system. From this case study, the initial findings indicate Penang is in dire need for a robust, sustainable transport system which can include rail transports and integration of different modes of transport. Moreover, the result also shows that the behaviour and attitude of Penangites towards public transportation needs to be changed. This study suggests a series of long term and short term solutions to enhance the performance of the transportation system in Penang. The balance alignment between the economic, social and environmental themes of sustainability will overcome the issues faced by the current transportation system in Penang.

Driving as a commuting travel mode choice of car owners in urban China: Roles of the built environment

Car dependency has been well recognized in low-density urban areas in developed countries, where travel demand management (TDM) has focused on providing transit-riding and non-motorized modes of transport, rather than restricting car ownership. In contrast, many megacities in China have adopted vehicle quota systems, fearing that additional car owners will become addicted to driving despite the soaring travel congestion and air pollution. This study investigated two research questions: Under what built environment characteristics would China's car owners give up driving for other commuting modes? Are the effects of built environment characteristics on car ownership and commuting mode choice spatially heterogeneous across zones? We use a household travel survey in Nanjing city, where no car quota system exists, to examine car owners' commuting mode choice. Innovatively, a multilevel discrete choice model with sample selection was used to reveal the effects of the built environment on car ownership and commuting mode choice simultaneously. We found significant spatial heterogeneities in car ownership and commuting mode choice across traffic analysis zones, while the built environment was found to play an important role. Our findings suggest that Chinese urbanites may be less addicted to driving than they appear, and city governments should be more progressive in regulating driving by improving the urban form.

COVID-19 and transport: Findings from a world-wide expert survey

Impacts of coronavirus disease 2019 (COVID-19) on the transport sector and the corresponding policy measures are becoming widely investigated. Considering the various uncertainties and unknowns about this virus and its impacts (especially long-term impacts), it is critical to understand opinions and suggestions from experts within the transport sector and related planning fields. To date, however, there is no study that fills this gap in a comprehensive way. This paper is an executive summary of the findings of the WCTRS COVID-19 Taskforce expert survey conducted worldwide between the end of April and late May 2020, obtaining 284 valid answers. The experts include those in the field of transport and other relevant disciplines, keeping good balances between geographic regions, types of workplaces, and working durations. Based on extensive analyses of the survey results, this paper first reveals the realities of lockdowns, restrictions of out-of-home activities and other physical distancing requirements, as well as modal shifts. Experts’ agreements and disagreements to the structural questions about changes in lifestyles and society are then discussed. Analysis results revealed that our human society was not well prepared for the current pandemic, reaffirming the importance of risk communication. Geographical differences of modal shifts are further identified, especially related to active transport and car dependence. Improved sustainability and resilience are expected in the future but should be supported by effective behavioral intervention measures. Finally, policy implications of the findings are discussed, together with important future research issues.

You have to drive: Impacts of planning policies on urban form and mobility behavior in Kuala Lumpur, Malaysia

This article investigates how planning policies have shaped urban form and mobility behavior in the rapidly urbanized metropolitan area of Kuala Lumpur, Malaysia. We argue that the complex chain of consequences of previous policies and their implementation processes can be understood from the socio-spatial dynamics that result from the interaction between people and their built environment. Using the case of Kuala Lumpur, we provide empirical evidence of these socio-spatial dynamics through (1) the identification of key policies, (2) an understanding of Kuala Lumpur’s spatial configuration using space syntax, and (3) in-depth interviews to reveal mobility behavior. Our findings suggest that Kuala Lumpur’s previous road expansion policies, national car project, and fragmented new town development have created an urban form that encourages vehicular instead of pedestrian movement. Consequently, this has induced an automobile dependence and culture that conflicts with the country’s current initiatives on sustainable development. For policymakers and planners, these findings provide awareness that policy impacts span across generations and scales, making them difficult to reverse and take a long time to be fixed. We conclude with practical insights on how to reverse the unsustainable path through socio-spatial innovations and research directions to address the ongoing vehicular dominance and automobile society in Kuala Lumpur.

Driving change: Exploring the adoption of multimodal local traffic impact assessment practices

Local governments in the US face growing public demands to reduce automobile dependence in order to forestall climate change, improve road safety, rein in sprawling peripheral land development, increase transportation equity, and enhance urban livability. As a result, many city and county leaders are looking for ways to provide alternatives to driving through the creation of more multimodal-supportive transportation systems and land use patterns. The academic literature has identified conventional traffic impact- assessment (TIA) practices—designed to ensure new developments do not increase automobile traffic congestion—as a barrier to supporting these multimodal efforts. Because of the growing emphasis on multimodality in many national, state, and regional policies and initiatives (e.g., Complete Streets, Vision Zero), we investigate whether and how communities were adapting TIA practices to better accommodate pedestrians, bicyclists, transit users, and other non-car travel modes in the land development process.