Why Cities are Good for the Environment
Contrary to our cultural narrative, cities are good for nature. Why? Because cities are natural and governed by the same processes that create ecological systems. In fact, cities may be the most useful tool we have for tackling some of the world’s most pressing problems. One study out of Yale University reported:
“New Yorkers have the smallest carbon footprints in the United States: 7.1 metric tons of greenhouse gases per person per year, or less than 30 percent of the national average. Manhattanites generate even less.”The Greenest Place in the US May Not Be Where You Think
How could this be? Shouldn’t the concrete jungle, full of garbage, pollution, and all those people, be terrible for the environment? In a single word: networks. Cities, like ecosystems, are tangled web of relationships. Connections provide opportunities for sharing, resource cycling, and niche creation. And the more people a city has, the more possible connections it contains.
Cities Increase Opportunities and Decrease Resource Needs (Per Capita)
The number of possible connections within a network increases disproportionately with the size of the network; this is known as Metcalfe’s Law. Niche opportunities form and fill. Resources start to cycle, and systems become more efficient. The more connections a system has, the less energy it needs (per unit). Physicist Geoffrey West was able to show that the scaling of organisms (networks of cells) holds true for cities (networks of people and resources). The more massive an organism, the less energy it requires per pound of body mass. So a blue whale requires less energy (per pound) than a mouse. As it turns out, cities require fewer resources (per person) than towns.
The densely connected nature of cities means that urban dwellers require less energy and resources than their rural counterparts. West shows that if you double the population of a city, you get a 15% per capita savings on the resources required to make it function. In this context, the rapid urbanization of our planet is good news – though not without challenges. As of this writing, 180,000 people are moving into cities each day. As of 2010, more than 50% of the world’s population lives in cities. In most developed nations, that percentage is closer to 80%. We are becoming an urban planet, and cities might be one of our best tools for tackling resource shortages and climate change.
A City Is A Place For Maximizing Connections
If cities are good for the planet, why do we believe the opposite? Probably because concentrating resources and opportunities also concentrates problems such as pollution and crime. The challenge for city builders is to maximize some effects while minimizing others.
In his book ‘Ecocities,’ architect Ricard Register describes a city as a place for maximizing connections. By this definition, a well-designed city maximizes opportunities, occupations, places to live, play, and socialize. Well-designed cities create options, opportunities, and serendipity – what Tony Hsieh called “collisions.” In contrast, poor urban design isolates us from each other, opportunities, and our potential.
Unfortunately, cities have often done a poor job of creating opportunities for nature. If cities are ecosystems, what happens if you consciously integrate built and natural environments? In what ways might nature improve our cities, but also, how might cities directly benefit nature?
The Biophilic City
If cities and ecosystems are parallel systems, can we combine them? Can we create cities that benefit the environment? We’re going to have to. Such a city might be called a biophilic city and is the focus of architects and city planners such as Ricard Register (Ecocity Builders) and Timothy Beatley (Biophilic Cities Network). There is no reason that cities couldn’t be among the most abundant and diverse systems on the planet.
Cities and ecosystems aren’t at odds because they’re the same thing – the sooner we realize this, the sooner we can get one designing cities that are truly part of the natural world. This has been the driving vision of my work.