New York City, USA. Climate change exposes cities, especially coastal ones, to greater environmental risks and uncertainty. In 2012, Manhattan suffered a major blackout affecting 600,000 people after Hurricane Sandy struck New York City. This was due to defensive walls not being high enough to protect the 14th Street power station from the storm surge. Photo by Iwan Baan / Getty Images, from Shaping Cities in an Urban Age

How better cities will save the world

By locking in good habits with infrastructure the mega cities of the future could help us avert ecological disaster

When the history of the early 21st century is written two key ‘c’ words will feature heavily. One is ‘cities’. “It took 200 years for the urban share of the world’s population to rise from 3 per cent to 50 per cent, from a few million people to 3.5 billion in 2010,” write economists and environmentalists Nicholas Stern and Dimitri Zenghelis in our new book Shaping Cities in an Urban Age.

“After more than doubling over this century, in all the centuries that follow we may add at most another one billion. This makes the current global urbanization era not just immense, but also a brief, once-in-history phenomenon.”

The other ‘c’ is 'climate'. Lord Stern was the World Bank’s chief economist and author of the Stern Review, which fellow economist Dimitri Zenghelis also contributed to; the review examined the likely effect of climate change on the global economy.

They both know that the rise of the city has coincided with the rise of global temperatures and, that if we’re not careful, the cities of the future could bring about catastrophic warming.

“The world’s infrastructure will substantially more than double in the next 20 years,” the authors write. “These investments will determine whether we have cities where we can move and breathe. If they lock in high-carbon and wasteful infrastructure, our chances of holding the global temperature increases to less than 2 degrees Celsius (35.6 degrees Fahrenheit) will be gone. And we could be heading to well over 3 degrees Celsius (37.4 degrees Fahrenheit), an increase not seen for around 3 million years, which would profoundly transform lives and livelihoods across the planet.”


Guangzhou, Guangdong Province, China. An extreme example of a hyper-dense city where population size has increased fivefold since 1990. Many  Chinese cities are designed to maximize density in order to boost productivity and efficiency. Photo by Xin Zhang
Guangzhou, Guangdong Province, China. An extreme example of a hyper-dense city where population size has increased fivefold since 1990. Many Chinese cities are designed to maximize density in order to boost productivity and efficiency. Photo by Xin Zhang

However, there’s no reason to assume that the cities of the 21st century need to be clogged with factory chimneys or car exhaust fumes.

As Stern and Zenghelis point out, manufacturing now tends to takes place outside the inner city environment, and a city’s success lies less in its deep-water ports, nearby mines or assembly plants, and more in the smart citizens that occupy and work within its limits.

“The clustering of people generates higher productivity and higher wages,” they write. “A mix of specialization and diversity generates a fertile environment for innovation in ideas, technologies and processes.”

“The physical advantage of London and New York’s natural harbours is no longer relevant in propagating their economic success,” they go on to say. “Paul Krugman famously said in his Nobel Prize lecture ‘God made the Santa Clara valley for apricots, not semiconductors’.”

The fact that we don’t need six-lane highways or acres of heavy industry in the city of tomorrow is encouraging. However, the trick for good future urban environments lies not in banning cars or manufacturing, but in locking in good habits, with early infrastructure 'pathways'.

"Making choices today about which type of infrastructure to invest in will lock cities into determined pathways of development for generations to come," explains our new book. "China has invested heavily in regional rail networks that link its growing cities together; however, in 2017 over a quarter of global automobile sales were Chinese, fuelling concerns about car dependency and pollution."

However, Stern and Zenghelis remain cautious; they know that a few bad choices over the next few years could screw up big cities for centuries.

“Patterns of urban mobility, production and behaviour can shape a city’s fortunes for decades and centuries to come,” they write. “Mistakes or shortcuts made in planning and urban geography risk locking in infrastructure, institutions and behaviours that can make cities less resilient and ill-placed to take advantage of structural transitions such as those taking place in low-carbon energy and transport networks.”


A spread from Shaping Cities in an Urban Age
A spread from Shaping Cities in an Urban Age

They cite well-known examples, such as the traffic jams of Mexico City, as well as less familiar cases, including “the sprawling car-dependent suburb of Victorville, 100 miles (161 kilometres) northeast of downtown Los Angeles, which suffered declines in population and the demolition of new homes after fuel prices doubled over the course of the first decade of the millennium.”

We can’t predict the price of gasoline in fifty years time, yet we can be pretty sure that generations to come will thank us for spending heavily on clean, green city infrastructure that encourage good practices.

“Cities are at the heart of human development, innovation and productivity growth,” the authors write. “Cities that are poorly planned will fail to grow and risk leaving humanity with a costly and potentially deadly climate. Together, these facts testify to the need for urgent policy action on urbanization. But the clock is ticking. The future of the world’s urban population will mostly be built in our lifetime and the cities we design over the next few decades will broadly define the cities we must live with for generations to come. Humanity has a narrow time frame in which to plan and design its future. It is our responsibility to ensure that this opportunity is not squandered.”


Shaping Cities in an Urban Age
Shaping Cities in an Urban Age

To hear more about those big city opportunities, head to the London School of Economics tonight (Wednesday September 26), to hear Lord Stern in conversation with fellow Shaping Cities authors Eduarda La Rocque, Saskia Sassen, and the books’ editor Ricky Burdett at the Shaping Cities launch. Meanwhile, for a more thorough examination of big city problems, order a copy of Shaping Cities in an Urban Age here.