The world, we’ve been told, is urbanizing rapidly. But the picture painted by researchers—dense, blocks of high-rises, new towers rising like staircases as cities evolve—obscures the true growth patterns reshaping the globe. Metropolises aren’t simply building up, they’re expanding out, and doing both at unprecedented rates that have serious consequences for the economy and the environment.
“Upward and Outward Growth: Managing Urban Expansion for More Equitable Cities in the Global South,” released yesterday by the World Resource Institute, paints a picture of cities building and ballooning. Researchers examined growth patterns for nearly 500 urban areas, using satellite imagery and radar data to measure growth vertically and horizontally. The results suggest land-use and density may be one of the defining issues of the next few decades.
“Some expansion of cities is inevitable to accommodate urban population growth,” said Anjali Mahendra, co-author of the new paper. “But the type of unmanaged, incessant growth in land area we are seeing not only leads to inequities in access to core urban services, like water, power and sewage, but also to greater economic and environmental risk for the entire city.”
Cities will have tripled in size between 2000 and 2030, and are on track to reach a projection of 80 percent growth in the next 18 years. The need for smart, dense, and sustainable growthis paramount, the report argues. Otherwise, the current state of unmanaged growth in land area will not only creates more inequality, but add to economic and environmental risk.
Many researchers and think tanks have argued that cities can save the environment; groups such as C40, a network of cities collaborating on environmental policies, have released studies showing that cities can combine growth with ambitious efforts to decrease carbon emissions.