To avoid system errors, if Chrome is your preferred browser, please update to the latest version of Chrome (81 or higher) or use an alternative browser.
Click here to login if you're an NAE Member
Recover Your Account Information
Author: George Bugliarello
Cities are home to half the world population—about 80 percent in the United States. These vibrant centers of activity impact global sustainability with their large footprints; concentrations of pollution and consumption; financial, technological, and knowledge networks; global business reach; and cultural influence. As the world urban population increases, however, risks to urban dwellers also increase.
Recent disasters have reminded us that most large cities are located in areas susceptible to natural disasters, such as floods, earthquakes, hurricanes, volcanic eruptions, and tsunamis. In addition, they are potential targets for mass destruction (e.g., Tokyo, London, Warsaw, etc.) and terrorism (e.g., New York, London, Mumbai, Madrid, and Baghdad). Cities are also subject to epidemics and dramatic social upheavals (e.g., the American, French, and Russian revolutions). The fact is that cities are risky, and the risks extend to the rest of the world.
Thus cities are critical national, as well as global infrastructures. Today, the urban and global contexts for sustainability often clash. For example, the introduction of electric cars in a city is likely to increase pollution from power plants in the countryside, and when a city expands, it destroys precious natural resources. Ultimately, however, the two contexts are bound to coincide. The challenge is how to make this happen without catastrophic consequences on either level.
Rapid advances in the knowledge of living systems, a myriad of inventions and innovations, and the rapid tempo of change in social paradigms, such as networking, flatter organizations, decentralization, conservation, and less authoritarianism, make it difficult to predict how these phenomena will shape cities in the future. We will need realistic models that consider cities as complex systems with biological, social, and technological components that interact with each other and with the external environment. Jonathan Fink’s article in this issue of The Bridge argues for an Urban Genome Project (inspired by the Human Genome Project) to develop road maps and predictions for individual cities based on both common urban characteristics and idiosyncratic features.
Security, economic, environmental, health, and quality of life are essential for evaluating the sustainability of all cities. A model that includes the biological, social, and technological dimensions of a city can inform decisions about potential trade-offs and synergies, predictions for the future, and unexpected or unwanted consequences. A simple example is the unemployment caused by the elimination of traditional, labor-intensive occupations that have provided livelihoods for generations. Another example is the decrease in the number of inhabitants per dwelling in the United States in the last 40 years. Even if the U.S. population remains stable, we will need a substantial number of new dwellings.
The optimization of technological systems can have profound biosocial implications. Centralization versus decentralization, for example, which implies a shift in control from community to individuals or vice versa, is a central factor in modernizing power-delivery and water-delivery systems. The article by Glen Daigger of C2HM Hill focuses on the effective, efficient treatment, delivery, and overall management of water resources.
New infrastructure and public works must also be designed to enhance the quality of life and contribute to urban sustainability. Co-location, equity, and sustainability are important criteria for the innovative structures and systems described in the article by Hillary Brown of New Civics Work and City College of New York.
Assessing the myriad feedback loops of a city is essential for ensuring good governance and adaptability, whether for reducing energy consumption, addressing traffic congestion, or enhancing quality of life. Aging populations, a feature of cities in the developed world and China, will require infrastructural modifications, particularly in suburbs, which have limited mass-transport capabilities. Older workers will also require new forms of employment in industry and services. Conversely, in the cities of the developing world, particularly in the Middle East, where the majority of the population is under 30. The pressing issue is to structure economies and industries to provide employment for them.
The unstoppable trend toward automation and the replacement of manual laborers is bound to reshape cities and, perhaps, lead to the realization of the age-old dream of machines that free us from the servitude of work. However, as a result, cities must be reorganized to ensure the livelihoods of displaced workers and ensure that cities remain sustainable.
U.S. suburbs, where half of urban populations live and where more jobs are being generated than in cities proper, are affected by unsustainable consumption of resources and changing socio-economic profiles. In many areas, middle class suburbanites are migrating back to cities, and city residents are migrating to suburbs in search of better schools for their children and better job opportunities.
As cities face these new challenges, they will need multidimensional, multiscale models, from the microscale of the individual to the hyper macroscale of urban agglomerates and megalopoles. The article by Catherine Ross and Myungje Woo of Georgia Tech raises issues related to megaregions—areas that encompass agglomerations of cities and suburban areas, and sometimes exurban and rural areas.
In general, cities in both the developed and developing world must improve social institutions to manage emerging problems related to demographics, security, resources, innovation, and quality of life. However, because of major differences in the development of biosocial and technological systems, cities in the more affluent developed world do not provide a satisfactory model for cities in the developing world, which are likely to have weaker service sectors, more widespread and desperate poverty, and a lower quality of life. Improving human services is one of the most important ways of improving efficiency and economic conditions in cities in the developing world. Xuemei Bai, of CSIRO Ecosystem Sciences, describes examples of sustainability experiments in Asia.
Today, a de facto global system connects, with different intensity, cities world-wide through loosely organized networks of geopolitical connections, trade, tourism, and cultural and personal relations, and the transmission of knowledge is a key element of the world infrastructure. However, these networks have not yet systematized the exchange of knowledge or enabled cities to take advantage of potential synergies.
Attempts to balance biological, social, and technological systems are raising new questions and forcing new policy choices, such as hard technological solutions versus potentially cheaper but often more difficult to accomplish biosocial soft solutions, or centralized versus decentralized systems.
Examples of cross-cutting policy choices include whether to subsidize an infrastructure system, such as a water supply system, or to subsidize only those who are unable to pay and charge the full cost to other users to ensure that the system remains economically viable. Other examples are decisions related to improving connections between individual health, social goals, and food technologies (e.g., ordinances for reducing salt and fats in restaurants and fast food).
From a different perspective, cities, with their concentrations of materials and resources, can be seen as “mines of the future.” A recent focus has been on the potential reuse of materials embedded in outdated urban structures and products, from bridges and buildings to personal electronic devices. The potential of “city mining” is the subject of an article by Tom Graedel of Yale University.
Urban concentrations increasingly impact global sustainability. They generate more than half of the world’s economic output and its pollution. Will they continue to grow? Will people from rural environments continue to migrate to cities in search of more opportunities and a better life? Will the dysfunctionalities in every large city abate or become more intractable, leading to smaller urban concentrations? What is the future of suburbs? How will cities adapt to major changes in population dynamics?
Answering these questions will require a better understanding of the complex phenomenon of urbanization, sustainability, and potential impacts on the future of our species. The articles in this issue, which address some of these questions, are part of ongoing discussions about the challenges of urban sustainability.