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Automobile dependency or car dependency is the concept that some city layouts cause automobiles to be favoured over alternate forms of transportation, such as bicycles, public transit, and walking.
In many modern cities, automobiles are convenient and sometimes necessary to move easily. [1] When it comes to automobile use, there is a spiraling effect where traffic congestion produces the 'demand' for more and bigger roads and removal of 'impediments' to traffic flow. For instance, pedestrians, signalized crossings, traffic lights, cyclists, and various forms of street-based public transit, such as trams.
These measures make automobile use more pleasurable and advantageous at the expense of other modes of transport, so greater traffic volumes are induced. Additionally, the urban design of cities adjusts to the needs of automobiles in terms of movement and space. Buildings are replaced by parking lots. Open-air shopping streets are replaced by enclosed shopping malls. Walk-in banks and fast-food stores are replaced by drive-in versions of themselves that are inconveniently located for pedestrians. Town centers with a mixture of commercial, retail, and entertainment functions are replaced by single-function business parks, 'category-killer' retail boxes, and 'multiplex' entertainment complexes, each surrounded by large tracts of parking.
These kinds of environments require automobiles to access them, thus inducing even more traffic onto the increased road space. This results in congestion, and the cycle above continues. Roads get ever bigger, consuming ever greater tracts of land previously used for housing, manufacturing, and other socially and economically useful purposes. Public transit becomes less viable and socially stigmatized, eventually becoming a minority form of transportation. People's choices and freedoms to live functional lives without the use of the car are greatly reduced. Such cities are automobile-dependent.
Automobile dependency is seen primarily as an issue of environmental sustainability due to the consumption of non-renewable resources and the production of greenhouse gases responsible for global warming. It is also an issue of social and cultural sustainability. Like gated communities, the private automobile produces physical separation between people and reduces the opportunities for unstructured social encounters that is a significant aspect of social capital formation and maintenance in urban environments.
According to the Handbook on estimation of external costs in the transport sector [2] made by the Delft University and which is the main reference in European Union for assessing the externalities of cars, the main external costs of driving a car are:
There are a number of planning and design approaches to redressing automobile dependency, known variously as New Urbanism, transit-oriented development, and smart growth. Most of these approaches focus on the physical urban design, urban density and landuse zoning of cities. Paul Mees argued that investment in good public transit, centralized management by the public sector and appropriate policy priorities are more significant than issues of urban form and density.
There are, of course, many who argue against a number of the details within any of the complex arguments related to this topic, particularly relationships between urban density and transit viability, or the nature of viable alternatives to automobiles that provide the same degree of flexibility and speed. There is also research into the future of automobility itself in terms of shared usage, size reduction, roadspace management and more sustainable fuel sources.
Car-sharing is one example of a solution to automobile dependency. Research has shown that in the United States, services like Zipcar, have reduced demand by about 500,000 cars. [3] In the developing world, companies like eHi, [4] Carrot, [5] [6] Zazcar [7] and Zoom have replicated or modified Zipcar's business model to improve urban transportation to provide a broader audience with greater access to the benefits of a car and provide "last-mile" connectivity between public transportation and an individual's destination. Car sharing also reduces private vehicle ownership.
Whether smart growth does or can reduce problems of automobile dependency associated with urban sprawl has been fiercely contested for several decades. The influential study in 1989 by Peter Newman and Jeff Kenworthy compared 32 cities across North America, Australia, Europe and Asia. [8] The study has been criticised for its methodology, [9] but the main finding, that denser cities, particularly in Asia, have lower car use than sprawling cities, particularly in North America, has been largely accepted, but the relationship is clearer at the extremes across continents than it is within countries where conditions are more similar.
Within cities, studies from across many countries (mainly in the developed world) have shown that denser urban areas with greater mixture of land use and better public transport tend to have lower car use than less dense suburban and exurban residential areas. This usually holds true even after controlling for socio-economic factors such as differences in household composition and income. [10]
This does not necessarily imply that suburban sprawl causes high car use, however. One confounding factor, which has been the subject of many studies, is residential self-selection: [11] people who prefer to drive tend to move towards low-density suburbs, whereas people who prefer to walk, cycle or use transit tend to move towards higher density urban areas, better served by public transport. Some studies have found that, when self-selection is controlled for, the built environment has no significant effect on travel behaviour. [12] More recent studies using more sophisticated methodologies have generally rejected these findings: density, land use and public transport accessibility can influence travel behaviour, although social and economic factors, particularly household income, usually exert a stronger influence. [13]
Reviewing the evidence on urban intensification, smart growth and their effects on automobile use, Melia et al. (2011) [14] found support for the arguments of both supporters and opponents of smart growth. Planning policies that increase population densities in urban areas do tend to reduce car use, but the effect is a weak one, so doubling the population density of a particular area will not halve the frequency or distance of car use.
These findings led them to propose the paradox of intensification:
At the citywide level, it may be possible, through a range of positive measures to counteract the increases in traffic and congestion that would otherwise result from increasing population densities: Freiburg im Breisgau in Germany is one example of a city which has been more successful in reducing automobile dependency and constraining increases in traffic despite substantial increases in population density.
This study also reviewed evidence on local effects of building at higher densities. At the level of the neighbourhood or individual development, positive measures (like improvements to public transport) will usually be insufficient to counteract the traffic effect of increasing population density.
This leaves policy-makers with four choices:
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Smart growth is an urban planning and transportation theory that concentrates growth in compact walkable urban centers to avoid sprawl. It also advocates compact, transit-oriented, walkable, bicycle-friendly land use, including neighborhood schools, complete streets, and mixed-use development with a range of housing choices. The term "smart growth" is particularly used in North America. In Europe and particularly the UK, the terms "compact city", "urban densification" or "urban intensification" have often been used to describe similar concepts, which have influenced government planning policies in the UK, the Netherlands and several other European countries.
Transport economics is a branch of economics founded in 1959 by American economist John R. Meyer that deals with the allocation of resources within the transport sector. It has strong links to civil engineering. Transport economics differs from some other branches of economics in that the assumption of a spaceless, instantaneous economy does not hold. People and goods flow over networks at certain speeds. Demands peak. Advance ticket purchase is often induced by lower fares. The networks themselves may or may not be competitive. A single trip may require the bundling of services provided by several firms, agencies and modes.
Bicycle-friendly policies and practices help some people feel more comfortable about traveling by bicycle with other traffic. The level of bicycle-friendliness of an environment can be influenced by many factors including town planning and cycling infrastructure decisions. A stigma towards people who ride bicycles and fear of cycling is a social construct that needs to be fully understood when promoting a bicycle friendly culture.
Congestion pricing or congestion charges is a system of surcharging users of public goods that are subject to congestion through excess demand, such as through higher peak charges for use of bus services, electricity, metros, railways, telephones, and road pricing to reduce traffic congestion; airlines and shipping companies may be charged higher fees for slots at airports and through canals at busy times. Advocates claim this pricing strategy regulates demand, making it possible to manage congestion without increasing supply.
Commuting is periodically recurring travel between one's place of residence and place of work or study, where the traveler leaves the boundary of their home community. By extension, it can sometimes be any regular or often repeated travel between locations, even when not work-related. The modes of travel, time taken and distance traveled in commuting varies widely across the globe. Most people in least-developed countries continue to walk to work, as the ancestors of all people did until the nineteenth century. The cheapest method of commuting after walking is usually by bicycle, so this is common in low-income countries, but is also increasingly practised by people in wealthier countries for environmental and health reasons. In middle-income countries, motorcycle commuting is very common. The next technology adopted as countries develop is more dependent on location: in more populous, older cities, especially in Eurasia mass transit predominates, while in smaller, younger cities, and large parts of North America and Australasia, communing by personal automobile is more common. A small number of very wealthy people, and those working in remote locations across the world, also commute by air travel, often for a week or more at a time rather the more typical daily commute. Transportation links that enable commuting also impact the physical layout of cities and regions, allowing a distinction to arise between mostly-residential suburbs and the more economically-focused urban core of a city, but the specifics of how that distinction is realized remain drastically different between societies, with Eurasian "suburbs" often being more densely populated than North American "urban cores".
Since the start of the twentieth century, the role of cars has become highly important, though controversial. They are used throughout the world and has become the most popular mode of transport in many of the more developed countries. In developing countries, the effects of the car on society are not as visible, however they are nonetheless significant. The development of the car built upon the transport sector first started by railways. This has introduced sweeping changes in employment patterns, social interactions, infrastructure and the distribution of goods.
Induced demand – related to latent demand and generated demand – is the phenomenon that after supply increases, and there is sufficient demand, price declines and more of a good is consumed. This is entirely consistent with the economic theory of supply and demand; however, this idea has become important in the debate over the expansion of transportation systems, and is often used as an argument against increasing roadway traffic capacity as a cure for congestion. This phenomenon, more correctly called "induced traffic" or consumption of road capacity, may be a contributing factor to urban sprawl. City planner Jeff Speck has called induced demand "the great intellectual black hole in city planning, the one professional certainty that everyone thoughtful seems to acknowledge, yet almost no one is willing to act upon."
Urban sprawl is the unrestricted growth in many urban areas of housing, commercial development, and roads over large expanses of land, with little concern for urban planning. In addition to describing a special form of urbanization, the term also relates to the social and environmental consequences associated with this development. Since the advent of the industrial era, sprawl has entailed no direct disadvantages, such as the loss of protection from medieval city walls. However, its disadvantages and costs include increased travel time, transport costs, pollution, and destruction of countryside. The cost of building the infrastructure needed for new developments is hardly ever recouped through property taxes, amounting to a huge subsidy for the developers and new residents at the expense of existing property taxpayers. In Continental Europe, the term peri-urbanisation is often used to denote similar dynamics and phenomena, but the term urban sprawl is currently being used by the European Environment Agency. There is widespread disagreement about what constitutes sprawl and how to quantify it. For example, some commentators measure sprawl only with the average number of residential units per acre in a given area, but others associate it with decentralization, discontinuity, segregation of uses, and so forth.
The car-free movement is a broad, informal, emergent network of individuals and organizations, including social activists, urban planners, transportation engineers, environmentalists and others, brought together by a shared belief that large and/or high-speed motorized vehicles are too dominant in most modern cities. The goal of the movement is to create places where motorized vehicle use is greatly reduced or eliminated, by converting road and parking space to other public uses and rebuilding compact urban environments where most destinations are within easy reach by other means, including walking, cycling, public transport, personal transporters, and mobility as a service.
Sustainable transport refers to the broad subject of transport that is sustainable in the senses of social, environmental and climate impacts. Components for evaluating sustainability include the particular vehicles used for road, water or air transport; the source of energy; and the infrastructure used to accommodate the transport. Transport operations and logistics as well as transit-oriented development are also involved in evaluation. Transportation sustainability is largely being measured by transportation system effectiveness and efficiency as well as the environmental and climate impacts of the system.
A carfree city is a population center that relies primarily on public transport, walking, or cycling for transport within the urban area. Districts where motorized vehicles are prohibited are referred to as carfree zones. Carfree city models have gained traction due to current issues with congestion and infrastructure, and proposed environmental and quality of life benefits. Currently in Asia, Europe and Africa, many cities continued to have carfree areas due to inception before the origin of the automobile. Many developing cities in Asia are currently using the proposed model to modernize its infrastructure.
Transportation demand management, traffic demand management or travel demand management (TDM) is the application of strategies and policies to reduce travel demand, or to redistribute this demand in space or in time.
Sustainable cities, urban sustainability, or eco-city is a city designed with consideration for social, economic, environmental impact, and resilient habitat for existing populations, without compromising the ability of future generations to experience the same. The UN Sustainable Development Goal 11 defines sustainable cities as those that are dedicated to achieving green sustainability, social sustainability and economic sustainability. They are committed to doing so by enabling opportunities for all through a design focused on inclusivity as well as maintaining a sustainable economic growth. The focus also includes minimizing required inputs of energy, water, and food, and drastically reducing waste, output of heat, air pollution – CO
2, methane, and water pollution. Richard Register first coined the term ecocity in his 1987 book Ecocity Berkeley: Building Cities for a Healthy Future, where he offers innovative city planning solutions that would work anywhere. Other leading figures who envisioned sustainable cities are architect Paul F Downton, who later founded the company Ecopolis Pty Ltd, as well as authors Timothy Beatley and Steffen Lehmann, who have written extensively on the subject. The field of industrial ecology is sometimes used in planning these cities.
Compared to other popular modes of passenger transportation, the car has a relatively high cost per person-distance traveled. The income elasticity for cars ranges from very elastic in poor countries, to inelastic in rich nations. The advantages of car usage include on-demand and door-to-door travel, and are not easily substituted by cheaper alternative modes of transport, with the present level and type of auto specific infrastructure in the countries with high auto usage.
Public transport is a system of transport for passengers by group travel systems available for use by the general public unlike private transport, typically managed on a schedule, operated on established routes, and that charge a posted fee for each trip. There is no rigid definition; Encyclopædia Britannica specifies that public transportation is within urban areas, and air travel is often not thought of when discussing public transport—dictionaries use wording like "buses, trains, etc.", and UK government COVID-19 guidance lists operators with no mention of air travel.
The compact city or city of short distances is an urban planning and urban design concept, which promotes relatively high residential density with mixed land uses. It is based on an efficient public transport system and has an urban layout which – according to its advocates – encourages walking and cycling, low energy consumption and reduced pollution. A large resident population provides opportunities for social interaction as well as a feeling of safety in numbers and "eyes on the street". It is also arguably a more sustainable urban settlement type than urban sprawl because it is less dependent on the car, requiring less infrastructure provision.
Automotive city or Auto City are cities that facilitate, and encourage, the movement of people via private transportation, through 'physical planning', e.g., built environment innovations and 'soft programming' e.g., social policy surrounding city street usage.
Sustainable urbanism is both the study of cities and the practices to build them (urbanism), that focuses on promoting their long term viability by reducing consumption, waste and harmful impacts on people and place while enhancing the overall well-being of both people and place. Well-being includes the physical, ecological, economic, social, health and equity factors, among others, that comprise cities and their populations. In the context of contemporary urbanism, the term cities refers to several scales of human settlements from towns to cities, metropolises and mega-city regions that includes their peripheries / suburbs / exurbs. Sustainability is a key component to professional practice in urban planning and urban design along with its related disciplines landscape architecture, architecture, and civil and environmental engineering. Green urbanism and ecological urbanism are other common terms that are similar to sustainable urbanism, however they can be construed as focusing more on the natural environment and ecosystems and less on economic and social aspects. Also related to sustainable urbanism are the practices of land development called Sustainable development, which is the process of physically constructing sustainable buildings, as well as the practices of urban planning called smart growth or growth management, which denote the processes of planning, designing, and building urban settlements that are more sustainable than if they were not planned according to sustainability criteria and principles.
The externalities of automobiles, similarly to other economic externalities, are the measurable difference in costs for other parties to those of the car proprietor, such costs not taken into account when the proprietor opts to drive their car. According to Harvard University, the main externalities of driving are local and global pollution, oil dependence, traffic congestion and traffic accidents; while according to a meta-study conducted by the Delft University these externalities are congestion and scarcity costs, accident costs, air pollution costs, noise costs, climate change costs, costs for nature and landscape, costs for water pollution, costs for soil pollution and costs of energy dependency.
Transport divide refers to unequal access to transportation. It can result in the social exclusion of disadvantaged groups.