Urban Legends

Jon Foley

Jonathan Foley is the director of the Institute on the Environment at the University of the Minnesota, where he is a professor and McKnight Presidential Chair in the Department of Ecology, Evolution and Behavior. He also leads the IonE’s Global Landscapes Initiative.

Where, exactly, is the “environment”?

It depends when you ask. In the transition from 1970s feel-good environmentalism to today’s pragmatic efforts, the notion of where we focus our environmental attention has fundamentally shifted.

We no longer think of the environment as being “out there” only in pristine locations. Instead, we now include the spaces around us, including our cities and towns—from our worst slums to our toniest suburbs. These built environments are just as important as the most pristine rainforest or coral reef. In fact, they may be far more important to the future of our planet.

As cities take center stage in our thinking of a sustainable future, they also represent an important paradox. On one hand, cities are tiny—at least in the planetary scheme of things. While we typically think of vast cities expanding into the countryside, gobbling up countless acres of farmland, this is something of a myth.

Across the Midwestern United States, for example, the total amount of farmland has remained largely unchanged in the past 50 years, even with increasing suburban sprawl. While suburbs are replacing some farms, including some very productive acres, the amount of farmland is still far greater than the total area of our cities, suburbs and roads. This may seem strange, especially when we see regular evidence of this sprawl in our daily commutes, but it’s true.

At the global scale, current satellite estimates show that our cities occupy just 650,000 square kilometers. That’s less than 1 percent of the world’s land area. In comparison, croplands cover 15 million square kilometers, while pastures cover 28 million square kilometers, together occupying roughly 35 percent of the world’s ice-free land surface.

So, cities are extremely small compared to the extent of global forests, grasslands, croplands, pastures and deserts. There’s a notion that urban sprawl has wiped out a large fraction of the world’s agricultural lands and natural ecosystems. But the numbers don’t add up.

Here’s the paradox: Even though they cover a tiny fraction of the world’s surface, cities have become the nexus of human activity on the planet, and are central to determining our relationship with the environment.

For the first time in human history, cities hold more than 50 percent of the world’s population. Homo sapiens is now an urban species—no longer completely tied to agricultural and rural landscapes—which represents a fundamental shift in our relationship to the environment. And this trend will continue. More than 90 percent of the world’s population growth will occur in cities across the developing world during the next 20 to 30 years.

Cities are also the focal points of global trade and industry, where 70 to 90 percent of our economic transactions take place, as well as global resource consumption.

In addition, cities have distinct environmental characteristics, ranging from urban heat islands and air quality issues to impervious surfaces that cause flash flooding. Not only do these factors challenge human health, they also exacerbate the vulnerability of urban populations to climate change and natural disasters.

But it’s not all bad news. Cities are also centers of creative energy, cultural innovation and entrepreneurship—the very things that will ultimately solve our sustainability crises.

Increasingly, cities around the world are pioneering new solutions to environmental, economic and social challenges. Not just the rich cities and ecotourism villages, but poor cities in some of the most challenged parts of the world. In this issue, Emily Gertz highlights several inspiring examples of innovative urban solutions, drawn mostly from war- and poverty-torn countries.

If they can do it, why can’t we? That’s the central question Momentum intends to address. We know there are solutions out there, so why not learn from them, adapt them to new situations and dramatically expand their impact?

Instead of creating more urban legends, we all need to roll up our sleeves and make even more legendary urban centers for the world.

Jonathan Foley
Director, Institute on the Environment