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.
Population density is a measurement of population per unit land area. It is mostly applied to humans, but sometimes to other living organisms too. It is a key geographical term.
Urban ecology is the scientific study of the relation of living organisms with each other and their surroundings in an urban environment. An urban environment refers to environments dominated by high-density residential and commercial buildings, paved surfaces, and other urban-related factors that create a unique landscape. The goal of urban ecology is to achieve a balance between human culture and the natural environment.
Urban sprawl is defined as "the spreading of urban developments on undeveloped land near a more or less densely populated city". Urban sprawl has been described as the unrestricted growth in many urban areas of housing, commercial development, and roads over large expanses of land, with little concern for very dense urban planning. Sometimes the urban areas described as the most “sprawling” are the most densely populated. In addition to describing a special form of urbanization, the term also relates to the social and environmental consequences associated with this development. In modern times some suburban areas described as “sprawl” have less detached housing and higher density than the nearby core city. Medieval suburbs suffered from the loss of protection of city walls, before the advent of industrial warfare. Modern disadvantages and costs include increased travel time, transport costs, pollution, and destruction of the countryside. The revenue for building and maintaining urban infrastructure in these areas are gained mostly through property and sales taxes. As most jobs in the US are now located in suburbs generating much of the revenue, although a lack of growth will require higher tax rates.
Sustainable transport refers to ways of transportation that are sustainable in terms of their social and environmental 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. Transport systems have significant impacts on the environment, accounting for between 20% and 25% of world energy consumption and carbon dioxide emissions. The majority of the emissions, almost 97%, came from direct burning of fossil fuels. In 2019, about 95% of the fuel came from fossil sources. The main source of greenhouse gas emissions in the European Union is transportation. In 2019 it contributes to about 31% of global emissions and 24% of emissions in the EU. In addition, up to the COVID-19 pandemic, emissions have only increased in this one sector. Greenhouse gas emissions from transport are increasing at a faster rate than any other energy using sector. Road transport is also a major contributor to local air pollution and smog.
Peter William Geoffrey Newman is an environmental scientist, author and educator based in Perth, Western Australia. He is currently Professor of Sustainability at Curtin University. He is best known for his contributions to the development of Perth's electrified metropolitan rail network through both activist and official consulting roles since the 1980s.
A sustainable city, eco-city, or green 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 will also includes minimizing required inputs of energy, water, and food, and drastically reducing waste, output of heat, air pollution – CO2, methane, and water pollution. Richard Register, a visual artist, 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.
Activity centre is a term used in urban planning and design for a mixed-use urban area where there is a concentration of commercial and other land uses. For example, the central business districts of cities (CBD) are also known as “Central Activities Districts” (CAD) (also known as Downtown in North America or "Central Activities Zone" in the United Kingdom in recognition of the fact that commercial functions are not the only things that occur there. The term activity centre can also be used to designate an area for mixed-use development, whatever its current land use happens to be.
Car dependency is the concept that some city layouts cause cars to be favoured over alternate forms of transportation, such as bicycles, public transit, and walking.
The EcoDensity Initiative was officially launched in 2006 in Vancouver, British Columbia, Canada, in conjunction with the World Urban Forum. The initiative was a response to deconcentration of urban land use due to urban sprawl. The initiative used density, design and land use as catalysts towards livability, affordability and environmental sustainability. Some of the program's objectives were to reduce car reliance, deliver more efficient urban land use, improve green energy systems and build a resilient and adaptable community. In high-density urban areas, utilizing the existing infrastructure and transit and community amenities tends to lead towards a more sustainable and livable state. Accordingly, EcoDensity was designed to strategically enhance densification with the primary aim of efficiently structured neighbourhoods, denser urban-patterns and increased affordable housing.
In urban planning, walkability is the accessibility of amenities by foot. It is based on the idea that urban spaces should be more than just transport corridors designed for maximum vehicle throughput. Instead, it should be relatively complete livable spaces that serve a variety of uses, users, and transportation modes and reduce the need for cars for travel.
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 may charge a posted fee for each trip. There is no rigid definition of which kinds of transport are included, and air travel is often not thought of when discussing public transport—dictionaries use wording like "buses, trains, etc." Examples of public transport include city buses, trolleybuses, trams and passenger trains, rapid transit and ferries. Public transport between cities is dominated by airlines, coaches, and intercity rail. High-speed rail networks are being developed in many parts of the world.
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.
An automotive city or auto city is a city that facilitates and encourages 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.
The sustainable urban neighbourhood (SUN) is an urban design model which is part of 21st-century urban reform theory, moving away from the typical suburban development of the UK and US towards more continental city styles. It emerged in the UK in the 1990s, specifically from pioneering work by URBED, an urban regeneration consultancy and research centre in Manchester.
Green urbanism has been defined as the practice of creating communities beneficial to humans and the environment. According to Timothy Beatley, it is an attempt to shape more sustainable places, communities and lifestyles, and consume less of the world's resources. Urban areas are able to lay the groundwork of how environmentally integrated and sustainable city planning can both provide and improve environmental benefits on the local, national, and international levels. Green urbanism is interdisciplinary, combining the collaboration of landscape architects, engineers, urban planners, ecologists, transport planners, physicists, psychologists, sociologists, economists and other specialists in addition to architects and urban designers.
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.
Cars affect many people, not just drivers and car passengers. 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 collisions; 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.
Climate change and cities are deeply connected. Cities are one of the greatest contributors and likely best opportunities for addressing climate change. Cities are also one of the most vulnerable parts of the human society to the effects of climate change, and likely one of the most important solutions for reducing the environmental impact of humans. More than half of the world's population is in cities, consuming a large portion of food and goods produced outside of cities. The increase of urban population growth is one of the main factors in air-quality problems. In the year 2016, 31 mega-cities reported having at least 10 million in their population, 8 of which surpassed 20 million people. However, secondary cities - small to medium size cities are rapidly increasing in number and are some of the fastest growing urbanizing areas in the world further contributing to climate change impacts. The UN projects that 68% of the world population will live in urban areas by 2050. Hence, cities have a significant influence on construction and transportation—two of the key contributors to global warming emissions. Moreover, because of processes that create climate conflict and climate refugees, city areas are expected to grow during the next several decades, stressing infrastructure and concentrating more impoverished peoples in cities.
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