As more and more people live in cities, local land-use and urban sustainability policies must be analyzed for their social and environmental tradeoffs in faraway places, asserts a Yale-led National Academy of Sciences study published today.
Urban and land-use sustainability are integrally connected, but often spatially disconnected. The paper, “Urban Land Teleconnections and Sustainability,” introduces the concept of teleconnections, borrowed from climate science analysis, as a conceptual framework for examining land change by explicitly linking it to urbanization.
Teleconnections refers to climate anomalies that are correlated over large geographic areas. For instance, when the waters of the North Atlantic go through a warming phase, the incidence of wildfires increases in the western United States.
“If we continue thinking of urban sustainability or land-use sustainability as a very localized issue and don’t link it to underlying drivers located far away, we’re not going to come up with policies or solutions that have meaningful systemic impact,” said Karen Seto, the paper’s lead author and associate professor in the urban environment at the Yale School of Forestry & Environmental Studies.
The urban population is projected to increase by almost 3 billion worldwide by 2050, and global urban land area is expected to increase by more than 1.5 million square kilometers—an area three times the size of Spain—by 2030.
The researchers assert that in an increasingly urban world, characterized by global flows of commodities, capital, information and people, and where land that provides goods and ecosystem services is becoming more segregated from consumers, teleconnections takes a global view of the consequences of urbanization and land changes that would otherwise go unrecognized.
For example, a holistic analysis of the projected increase in U.S. population of 100 million by the end of the century would consider the configuration of the landscape for housing, the amount of timber required and where it would come from, and the land-use impacts in the area where the wood originated.
“It forces us to talk about sustainability in terms of tradeoffs,” said Seto. “It’s not as simple as saying that you’re going to lower your carbon footprint, plant trees or recycle, because there are many other impacts on the land and resources, and we need to calculate what those are.”
The researchers acknowledge that social and ecological benefits accrue from the use of local resources and ecosystems, however decisions and behaviors that are local or even regional in scope do not account for the consequences of teleconnections that may undermine sustainability efforts elsewhere.
“Eating locally might undermine the livelihoods of distant farmers, who may be using less energy-intensive methods to produce food than local growers,” said Seto. “Put another way, sustainability initiatives often focus on the importance of place while ignoring the processes of urbanization.”
Besides Yale University, the institutions involved in the research are the University of Copenhagen, Arizona State University, Humboldt University and Helmholtz Centre for Environmental Science, Hunter College, Ohio State University, European Environmental Agency and Technical University of Zvolen, and University of London.