Cities provide paths from poverty to sustainability

May 1, 2017, Santa Fe Institute
Residents plan how best to bring municipal services into an underserved neighborhood. Credit: Shack/Slum Dweller International (SDI), South Africa

New international agreements commit all UN member nations to solving humanity's greatest challenges over the next few decades, from eliminating extreme poverty and unhealthy living conditions to addressing climate change and arresting environmental degradation.

But how we'll achieve these extraordinary goals in such a short amount of time remains a major challenge.

According to a new paper published this week in PNAS, creating a quantitative and systematic understanding of how cities generate wealth and better living conditions for their residents would be a big step forward.

"The processes of human and economic growth that cities and urbanization typically unleash are the only way we know to generate such monumental change so quickly," says Luís Bettencourt, a professor at the Santa Fe Institute and one of the leading authors of the study. "But we also know that processes of development in cities can create many terrible unintended consequences, including debilitating economic inequality and ."

To get a quantitative snapshot of development processes in rapidly urbanizing nations at different scales—from neighborhoods to nations—researchers from the Santa Fe Institute and Arizona State University analyzed neighborhood-level data in several nations in Africa and Latin America.

The authors propose a simple index that can measure progress consistently. In the study, they show how this index captures development priorities expressed in surveys by the residents of 677 slums in 10 nations and can also be measured using data available from census in nations such as Brazil and South Africa. This approach reveals how quantities such as household income, access to basic services, and permanent housing change systematically from to city and neighborhood to neighborhood.

A woman maps out how to bring municipal services into an underserved neighborhood. Credit: Shack/Slum Dwellers International (SDI), South Africa
"When you measure systematically, you find that people typically have higher incomes and more access to services in larger cities," says Bettencourt. "You see that large cities nucleate improving within their nations which then spread to other places. But you also find systematic large inequalities, when you look at it neighborhood by neighborhood."

When the researchers compared index scores across neighborhoods, they found a consistent picture of spatially segregated rich and poor , which appears most pronounced in cities just beginning to climb the development ladder.

"Some inequities are, to a certain extent, inevitable," says Christa Brelsford, the first author of the paper. At the time of the research, she held a postdoctoral fellowship through Arizona State University and the Santa Fe Institute. She is now a Liane Russell fellow at Oak Ridge National Laboratory. "There will always be people and places with access to 'just a little bit more', but we found that the degree of inequity among access to housing and services varies a great deal across different cities."

Brelsford adds that "by directly measuring heterogeneity in infrastructure access, we can provide a general model for how to support more just, equitable, and sustainable development that is consistent with the UN Sustainable Development Goals."

To help solve the main challenges of urban sustainability within our lifetimes, the paper calls for systematic analyses in more cities worldwide, complemented with new data and additional objectives.

The authors believe that such consistent and systematic analyses are now possible and constitute a critical first step toward achieving sustainability objectives set by individual cities, as well as the United Nations' Sustainable Development Goals and the New Urban Agenda.

Read the paper, "The Heterogeneity and Scale of Sustainable Development in Cities," in this week's special feature of PNAS devoted to Sustainability in an Urbanizing Planet.

Explore further: What can the New Urban Agenda and Sustainable Development Goals do for cities?

More information: Christa Brelsford el al., "Heterogeneity and scale of sustainable development in cities," PNAS (2017).

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3 / 5 (2) May 01, 2017
The solutions are simple but not easy. You have to start with a clear understanding of what the real problems are so you can ignore the ones that are not problems or that no one can fix.

Economic inequality is not a problem. Widespread poverty is a problem. Lack of access to clean water and inexpensive energy (electricity), unhealthy living conditions, and environmental degradation are all problems associated with poverty. Climate change is not a problem. Its effects are so gradual that people can easily adapt. The wealthier they are the easier they can adapt.

So the focus should be on helping build wealth. History has repeatedly shown that the best way to rapidly increase widespread wealth in a country is to become free, with minimal regulations on business, strong protections of freedoms and property rights, and strong enforcement to minimize lawbreaking and corruption. The rest of the problems resolve themselves quickly, usually within a generation.
5 / 5 (2) May 01, 2017
Freedom House monitors freedom in the world and publishes a map. It's easy to see from their map that freedom corresponds to widespread wealth and generally also corresponds to protection of the environment.

There are countries like Saudi Arabia, Russia, and China that are very wealthy but the wealth is not widespread. It's concentrated in a small group of elites because of lack of freedom.

Freedom = widespread wealth. Simple really, but getting to freedom can be a long, painful and bloody process.

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