Urbanites, even in poor cities, tend to have the money to consume more than their rural brethren, Rees says, so cities tend to have outsized ecological footprints. However, he notes, public transportation, efficient heating, streamlined services, and other things that are economical in cities but not elsewhere can ease urbanization's impact on the environment. “Cities do enable—if we organize them properly—the displacement of private cars in favor of public transportation, cogeneration, recycling, and remanufacturing,” he says. “In general, high-income cities increase the ecological footprint because of rising incomes and rising consumption, but we could—through intervention in the economy, appropriate planning, densification, and tax policies—turn it around. But so far we are choosing not to do so.
”The number of urbanites has tripled since the early 1960s and now represents half of the world's 6.5 billion population, which approximately doubled during that time. Meanwhile, our global footprint has more than doubled since the early 1960s, when it took up half the planet's renewable resources. It now exceeds the Earth's resources by about 25 percent, meaning that we are degrading the planet's ability to support us. If you think of those resources as a bank account, we are no longer living only off the interest. We are spending capital.
So how to disentangle the assertion of urbanites as bad actors? Well, the first is to understand the comparison. When comparing the Environmental Footprint of an urbanite to a ruralite, I think the assertion probably holds true. Let's consider a developed economy comparison of an urbanite in a city like New York or London to their rural counterpart - it is probably true that the urbanite both consumes net more products and services as well as requires those products and services to be imported in to the city and disposed of out of the city, whereas the ruralite may consume more locally produced products, and be able to dispose of them more efficiently (if not, necessarily, any more safely). Similarly, in a developing country standpoint, the challenge often may be that those ruralites are, in fact, rural poor, and simply do not have the economic capability to consume at parity with their urban counterparts, even the urban poor. In both cases, the impact is likely to bias the comparison against the urban population.
The challenge in that comparison lies in the fact that, at least as far as modern economies have grown, people get drawn to urban centers based on the ability of cities to create wealth, jobs, and opportunity. The logical conclusion of a finding that rural living is more sustainable that urban living - which would be to encourage more people to live in rural settings - does not hold at scale, because rural economies generally can't sustain the population mass, and therefore, those populations migrate to urban centers. Hence, global trends towards urbanization.
I think the more salient and actionable lessons from the analysis are to focus on patterns of consumption (among both rural and urban populations, but probably exaggerated among urban populations), trying to align consumption more closely with sustainability (i.e., how can we convince people to simply consume less) and separately, investing in public policy that continues to increase the efficiency by which products and services can be delivered to urban markets.
And a last note - the greater difficulty in the urban vs. rural comparison above is that it is probably not the demographically relevant comparison. Rather, of a greater concern is the trend to suburbs, exurbs, and other types of "cities" where citizens have the "richer" consumption patterns of urban environments, but benefit from none of efficiencies in delivering those services created by dense, urban environments. This rapid development of suburbia, and the patterns of living and consumption there are the demographic trend probably warrants the most concern.