Research agenda for low-carbon mobility: Issues for New World cities

ABSTRACT

Low-carbon mobility (LCM) features strongly in debates about the sustainability of cities and their resilience in the face of demographic, economic, and climate change. Transport is a major source of carbon emissions and there are indications that these continue to increase, despite the considerable recent advances in vehicle, engine, and fuel technologies. Reducing carbon emissions from transport may become more difficult, not easier. A particular issue relates to the New World cities, typified by those of North America and Australasia, which largely developed from the latter half of the nineteenth century onward and whose transportation systems were largely based around private vehicle ownership and usage. These cities are typically composed of low-density, dispersed suburbs, which are highly car dependent and resource and carbon emission intensive. This article develops a research agenda directed at determining and testing policy and planning measures relevant to the quest for low carbon mobility in New World cities. It suggests a rich agenda for essential research on LCM. Much of this agenda falls within the realm of the integration of transport and land use, with attention to urban design details to enhance the perceptions of and opportunities to use low carbon transport alternatives. Research topics identified for LCM research include (1) urban design and land use–transport integration (LUTI), (2) low carbon mobility policies directed at achieving widespread behavior change, (3) opportunities for new technology and its application, including requirements for systems and infrastructure, and (4) analysis and tools for informed decision making, including modeling, measurement, visualization, and especially assessment.     

The role of road safety in a sustainable urban mobility: An econometric assessment of the Spanish NUTS-3 case

There has been a structural change in mobility in major Spanish cities in recent decades, with a switch to the pattern followed in other countries in the area. A shift has taken place from a traditional Mediterranean model to a North American city stereotype, with uncontrolled motorization and major implications for public health. This article specifically analyzes negative road safety-related externalities that result from this process, given that the trend seems to show a steady decline in road safety accidents on urban roads in Spain, with major differences among NUTS-3 provinces. The objective is to evaluate the factors that empirically explain these differences for the 2003–2013 period using a panel data analysis. Results show that a key role is played by urban development variables, such as population density and improvements in health services, with advances linked to more accessible and sustainable urban transportation, such as the Smart City concept. Not only does this article close a gap in the literature, but the findings can also serve as a practical guide for the development and implementation of urban mobility and road safety plans, and reveals the special needs of the most vulnerable groups.     

Accessibility,mobility, and realized travel behavior: Assessing transport disadvantage from a policy perspective

Limited accessibility and mobility can result in decreased quality of life and well-being, as well as social exclusion. In the United States (U.S.), rural and small urban communities suffer from transport disadvantage due to a lack of transit and a low density of employment, education, recreation, and other opportunities. While the international literature has produced a number of methods and frameworks to assess transport disadvantage and its impacts, the U.S. has lagged behind in providing pertinent studies. The objective of this paper is to establish comprehensive measures that can support the identification, evaluation, and quantification of transport disadvantage in U.S. rural and small urban communities, considering both data availability and the unique characteristics of the U.S. The concept of transport disadvantage in this paper denotes the disadvantage of a specific population group or area that results from a difficulty accessing transportation and/or opportunities. To achieve this objective, this paper develops a spatial multi-perspective approach to account for the three essential elements of transport disadvantage: accessibility, mobility, and realized travel behavior.The developed approach provides an assessment of transport needs and need gaps that can be of benefit to small urban and rural communities and their planning practices, as well as to transport providers. The analysis in this paper suggests that—from a policy perspective—a combination of measures that account for all three essential elements of transport disadvantage should be considered, because the results of each measure complement those of the others. This paper illustrates the proposed approach using a case study of Indiana. The findings suggest that a great part of rural and small urban Indiana presents a low density of opportunities and that transport-disadvantaged residents of such areas might experience the impacts of low transit supply as well. In addition, the findings suggest that residents of rural and small urban areas travel longer distances on their day-to-day activities.This paper attempts to advance the national research pertaining to transport disadvantage and provide a framework that can support planning and policy decisions at the community as well as at the state level.     

Spatiotemporal accessibility to supermarkets using public transit: an interaction potential approach in Cincinnati,Ohio

Improving nutrition in urban regions involves understanding which neighborhoods and populations lack access to stores that sell healthy foods, such as fruits and vegetables. To this end, recent work has focused on mapping regions without access to places like supermarkets, often terming them ‘food deserts’. Until recently, this work has not considered residents’ mobility as facilitated by transportation systems, and even among those that do, few have considered alternative forms of transportation, like public transit, opting for automobile-oriented travel assumptions. This paper analyzes people’s spatio-temporal constraints to accessing supermarkets, and focuses on the transit commuting population. Analysis of commute data from Cincinnati, Ohio shows there are a significant number of residents that have improved access to supermarkets when a grocery shopping trip is made on the way home from work, than if they were to depart from their home location. These results extend previous work showing relatively few automobile commuting residents have better access to supermarkets given their work locations.     

How to plan for regional accessibility?

In order to address some of the shortcomings of traditional urban transportation planning, it is argued that a shift is needed from planning for mobility to planning for accessibility. Accessibility is a well-known and studied concept within the scientific literature. Its use in practice however is limited. This paper explores the ways of using the concept of accessibility in planning practice, with a special focus on the phase of policy design. Using the Amsterdam Region as an example, it is illustrated how simple accessibility measures can help planners with the design of integrated transport and land-use policies that call for different solutions than the traditional approach.     

“I am like a deaf,dumb and blind person”: Mobility and immobility of Chinese (im)migrants in Flushing,Queens, New York City

This paper contributes to research on daily mobility experience of (im)migrants in cities and expands the conceptualizations of mobility by examining intentionality and its relations to locality. Through place-based research on mobility and immobility of Chinese (im)migrants in Flushing, Queens, New York City, this paper explores: 1) mobility patterns of recent (im)migrants in an urban setting; 2) the constraints, resources and their coping strategies for everyday mobility; and 3) the dialectal relationship between voluntary and involuntary immobility, and between mobility and ethnic communities. This study reveals that immobility is not always the result of inaccessibility, but structural barriers in the broader society such as socioeconomic inequality and racial discrimination. Involuntary immobility encourages overdependence on locality. With its high place accessibility, Flushing provides (im)migrants with a plethora of ethnic mobile resources, as well as social networks and community resources. The relative immobility among Chinese (im)migrants in Flushing is compensated by the flows and movements of people, goods and information both at the local and transnational scale. The contrast between insider-ness and outsider-ness further enhances their attachment to the local community and discourages them from moving. Thus, locality mitigates involuntary immobility but paradoxically nurtures voluntary immobility that hinders the transfer of potential mobility to actual mobility, and physical mobility to social mobility. Without considering locality, stillness is easily mistaken for immobility; without considering intentionality, accessibility is easily equated to mobility. Therefore, solutions to transportation equity do not lie solely in transportation accessibility itself, but more broadly in individual capability, immigration policy, labor market equality and community development.     

Uber service area expansion in three major American cities

Chiefly led by Uber, on-demand ride-hailing services have transformed the urban American transportation landscape in merely the past decade. Utilizing the proliferation of internet-enabled smartphones, this app-based company has provided city inhabitants with a convenient and reliable door-to-door mobility service, which has arguably improved car-based accessibility while also generating a host of negative environmental and societal externalities. While to date the utilization of Uber has largely been an urban phenomenon, the lasting success of this new mobility option likely rests within its ability to expand its services into suburban communities. Yet, given the competitive nature of the ride-hailing marketplace and genuine concerns over passenger and driver anonymity, transportation planners and urban policymakers have been stymied in their ability to access the disaggregate data sets needed to help assess whether these services are in fact extending beyond city centers and identify which factors may be contributing to any expansion into more peripheral suburban neighborhoods. By introducing a creative strategy using the privacy-related suppression processes of Uber Movement data, this study quantifies the continued expansion of Uber's ride-hailing service into outlying communities from 2016 to 2018 by employing a multilevel modeling approach to recognize the neighborhood-level socioeconomic and built environment factors most related to this service expansion in three major American cities: Boston, San Francisco, and Washington, DC.     

Multi-scale and multi-modal GIS-T data model

The role of urban transportation becomes increasingly important with the change of demographic and economic patterns. The trend to expect better urban living standards for inhabitants has significantly increased the demand for efficient and sustainable multi-modal transportation systems in large urban areas. This should favour emergence of balanced transportation system that uses each mode for what it does best. But still, the development of urban transportation policies partly relies on the availability of appropriate data and information. The research presented in this paper proposes a multi-modal and multi-scale GIS-T data model. The model introduced takes into account different transportation modes and integrates them within an integrated data model designed using an object-oriented approach. The model allows the development of specialised services designed after a survey and study of users’ and planners’ requirements. The approach is applied in a district of the city of Guangzhou and validated by a prototype development. This experimental system enables transportation planners and decision-makers to take better decisions effectively, and provides high-quality geospatial information-based services to final end-users.     

Assessing the role of network topology in transportation network resilience

The abstract representation of a transportation system as a network of nodes and interconnecting links, whether that system involves roadways, railways, sea links, airspace, or intermodal combinations, defines a network topology. Among the most common in the context of transportation systems are the grid, ring, hub-and-spoke, complete, scale-free and small-world networks. This paper investigates the role of network topology, and the topology’s characteristics, in a transportation system’s ability to cope with disaster. Specifically, the paper hypothesizes that the topological attributes of a transportation system significantly affect its resilience to disaster events. Resilience accounts for not only the innate ability of the system to absorb externally induced changes, but also cost-effective and efficient, adaptive actions that can be taken to preserve or restore performance post-event. Comprehensive and systematically designed numerical experiments were conducted on 17 network structures with some relation to transportation system layout. Resilience of these network structures in terms of throughput, connectivity or compactness was quantified. Resilience is considered with and without the benefits of preparedness and recovery actions. The impact of component-level damage on system resilience is also investigated. A comprehensive, systematic analysis of results from these experiments provides a basis for the characterization of highly resilient network topologies and conversely identification of network attributes that might lead to poorly performing systems.     

Level of service: the politics of reconfiguring urban streets in San Francisco, CA

Intersection level of service (LOS) is a traffic engineering concept which measures how streets handle automobile traffic. It is widely used in transportation planning as an indicator of delay at intersections. The use of LOS is often criticized for its bias towards automobiles at the expense of bicycling, transit, and walking, and it complicates smart growth or compact development. In San Francisco, California, there is a political movement to eliminate the use of LOS in planning. But this movement has met significant obstacles and debate. In this paper I explore how the debate in San Francisco is unfolding and suggest implications for broader efforts to reconfigure urban streets and urban space in the United States and globally.     

Unveiling large-scale commuting patterns based on mobile phone cellular network data

In this study, with Estonia as an example,we established an approach based on Hidden Markov Model to extract large-scale commuting patterns at different geographical levels using a massive amount of mobile phone cellular network data, which is referred to as Call detail record (CDR). The proposed model is designed for reconstructing and transforming the trajectories extracted from the CDR data. This step allowed us to perform origin-destination matrix extraction among different geographical levels, which helped in depicting the commuting patterns. Besides, we introduced different techniques for analyzing the commuting at the urban level. Our results unveiled that there is great potential behind mobile data of the cellular networks after transforming it into meaningful mobility patterns. That can easily be used for understanding urban dynamics, large-scale daily commuting and mobility. The aggressive development and growth of ubiquitous mobile sensing have generated valuable data that can be used with our approach for providing answers and solutions to the growing problems of transportation, urbanization and sustainability.     

Who could benefit from a bus rapid transit system in cities from developing countries? A case study from Kampala,Uganda

The present rapid urban growth of cities from developing countries causes negative externalities such as lagging infrastructure development. In combination with rapidly rising motorized vehicle use this leads to severe traffic congestion affecting the mobility of the urban residents. Therefore many urban governments are planning to improve their transport and mobility situations with mass rapid transit systems of which a bus rapid transit (BRT) is a rather easy system to implement at reasonable costs. However, due to high urban inequalities the effects of urban traffic and potential improvements of the urban transport system for the diverse group of urban residents can differ significantly. In our case study Kampala (Uganda) four main groups were identified through cluster analysis of socio-economic and residential data gathered through interviews: extreme poor, poor, middle income and rich. Each group experiences a different mobility with the extreme poor being the most vulnerable group. The planned BRT system aims to decrease the average travel time but risks to exclude the lowest income class since not enough attention is paid to the affordability of the system to all residents. Therefore we argue for a policy that works from bottom up and pays attention to the internal diversity of the population.     

Multiple views of sustainable urban mobility: The case of Brazil

The aim of this work is to identify key factors of a sustainable urban mobility concept in a particular context. A multiple criteria decision analysis method was developed to identify the main variables associated to the concept. Looking at the results obtained in 11 cities of the five Brazilian regions, we conclude that the method is able to capture the different views and approaches discussed in the formulation of the mobility concept. Therefore, it can be used as a starting point for the formulation of public policies and also in the development of tools designed for monitoring the mobility conditions.     

Transportation network and venture capital mobility: An analysis of air travel and high-speed rail in China

Transportation network plays a critical role in reshaping the spatial geographical economy in terms of population, urban form, output and so on. But the impact of transportation on capital mobility is seldom revealed. Using venture capital investment events and airline network as well as high-speed rail network in China, this paper examines the effects of transportation network on capital mobility. We find that 1% decline in travel time will lead to increase in VC investment deals by 0.02. Heterogeneous results indicate that small firms, young firms, and emerging industries benefit more from the transportation network, which demonstrates the role of transportation network in alleviating information asymmetries. In addition, heterogeneity on VC flow direction offers suggestive evidence that transportation network is likely to alleviate development imbalance within wealthier cities while widening the gap between wealthier cities and poorer cities.     

Inter-regional and inter-temporal analysis of travel behaviour for Asian metropolitan cities: Case studies of Bangkok, Kuala Lumpur, Manila, and Nagoya

The unprecedented demand for travel experienced in Asia, in conjunction with the economic development of the1980s, has resulted in a number of detrimental effects on urban systems. Economic development has certainly intensified per capita income enhancing personal mobility. In Asia, private vehicle ownership and usage have continued to be recognised as an obligatory element of travel for many. Undoubtedly there is a direct relationship between vehicle ownership and public transport usage. Inter-regional and inter-temporal investigations of travel behaviour in Asian cities are therefore necessary to develop an understanding of the future transportation system including suitability and the role of public transport. Since travel data are scarce in Asian countries, inter-regional or inter-temporal travel behaviour investigations do not exist to date. Several travel demand models are developed using discrete choice modelling techniques and Bangkok, Kuala Lumpur, Manila, and Nagoya as case studies. Estimation results of the mode choice models are successfully incorporated to compare travel behaviour trends in selected cities in Asia. The developed models are tested for spatial and temporal transferability.     

Improving rural accessibility by locating multimodal mobility hubs

In rural regions, public transportation is often characterized by low accessibility as well as long waiting and travel times. In order to improve rural transportation systems, public decision-makers intend to implement alternative on-demand mobility modes. Herein, new intermodal travel itineraries with transfers at multimodal mobility hubs may enable faster public connections and thereby strengthen public transportation. Against this background, we present a decision support tool for locating multimodal mobility hubs to improve intermodal accessibility. As objectives, we aim at maximizing accessibility to workplaces and to places of private need. Our model decides on locations of multimodal mobility hubs and on the available on-demand mobility modes offered in addition to existing public transportation. We develop our model in an agile process together with rural decision-makers in the district of Heinsberg, Germany, and apply it in a real-world case study. As input for our model, we account for the existing public transportation system, identify points-of-interest, and estimate commuting volumes to workplaces based on official commuting data. Results promise a high potential to improve accessibility in rural areas. However, most of the improvement stems from unimodal car sharing trips.     

Investigating socio-spatial differences between solo ridehailing and pooled rides in diverse communities

Transformative mobility services present both considerable opportunities and challenges for urban mobility systems. Increasing attention is being paid to ridehailing platforms and connections between demand and continuous innovation in service features; one of these features is dynamic ride-pooling. To disentangle how ridehailing impacts existing transportation networks and its ability to support economic vitality and community livability it is essential to consider the distribution of demand across diverse communities. In this paper we expand the literature on ridehailing demand by exploring community variation and spatial dependence in ridehailing use. Specifically, we investigate the diffusion and role of solo requests versus ride-pooling to shed light on how different mobility services, with different environmental and accessibility implications, are used by diverse communities. This paper employs a Social Disadvantage Index, Transit Access Analysis, and a Spatial Durbin Model to investigate the influence of both local and spatial spillover effects on the demand for shared and solo ridehailing. The analysis of 127 million ridehailing rides, of which 15% are pooled, confirms the presence of spatial effects. Results indicate that density and vibrancy variables have analogue effects, both direct and indirect, on demand for solo vs pooled rides. Instead, our analysis reveals significant contrasting effects for socio-economic disadvantage, which is positively correlated with ride-pooling and negatively with solo rides. Additionally, we find that higher rail transit access is associated with higher demand for both solo and pooled ridehailing along with substantial spatial spillovers. We discuss implications for policy, operations and research related to the novel insight on how pooled ridesourcing relate to geography, living conditions, and transit interactions.     

Livelihoods in motion: Linking transport,mobility and income-generating activities

During the past decade, there has been an increased focus on mobility in the social sciences linked to the so-called ‘mobility turn’, which claims that as mobility is so pervasive it should not be viewed as a rupture in society but as a normal way of life. This is certainly the case in urban contexts of sub-Saharan Africa where mobility forms an integral part of livelihood and income-generating activities. Drawing on in-depth qualitative research conducted in Accra, the capital of Ghana, this paper explores the mobility of urban residents in differing parts of the city in relation to their livelihood strategies. Through illustrating the ways in which the mobility of urban residents is aided or hindered by Accra's transport system, and by examining how this in turn influences their livelihood strategies, the paper contributes to an alternative new mobilities paradigm that is more considerate of, and builds upon insights from, the global South where such research has a longer pedigree than in the global North.     

Integrated transport planning in the UK: From concept to reality

This paper explores the need for new planning authority practices and structures that can accommodate new policy demands, synergies and approaches to urban management in the UK. Initially it considers recent UK government ideas on the integration of transport and land use planning, exploring how the concept has been located carefully in relation to both established and emerging debates about, for example, sustainability, mobility and structures of governance. The paper then moves on to consider the relationship between these concepts in EU transport discourse taking an example from Sweden of what an integrated urban transport policy might look like on the ground. The final section develops a model of integration and applies this analytic construct to assess integration practices and outcomes of urban mobility management at the local authority level in England. The research uncovers implementation failures including duplication of procedures, failures in communication and the lack of clear and resourced responsibilities.     

Analysis of job accessibility promoted by ride hailing services: A proposed method

The concept of accessibility as an element of the interaction between land use and transportation is widely applied in studies of urban mobility. The idea that the accessibility of a place can be measured by the variety and quantity of opportunities available at the destination has led to the creation and adaptation of various indicators. The new mode of transport known as ride hailing (RH) has grown in recent years throughout the world, making it necessary to evaluate its impact on modern society, mainly its interaction with other modes. Therefore, this article presents a method to calculate the accessibility of formal jobs generated by public transportation (PT) and RH, to compare the results. For this purpose, we made adaptations to two indicators commonly used in the literature: the Gini index combined with the Lorenz curve; and the location quotient (LQ). The integrated structure is demonstrated in the context of a case study conducted in four districts of the city of Rio de Janeiro, Brazil. By applying the proposed method, we found that in regions with high commercial concentration and number of jobs, with the fares charged in the city, the accessibility to formal jobs generated by RH is greater than that associated with PT when more than two passengers travel together. This information on the competition or complementarity of the two modes can be useful to make decisions for regulation of the transport sector in general, and ride hailing in particular.