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Civil, Environmental and Sustainable Engineering (2014/02/09)
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spread to the surrounding countryside as well.23

But tomorrow’s city must perform a tricky balancing act. It will have to grow at breakneck speed, while pro-

viding both services and economic opportunity to its people. And it must do this in a world with severely
constrained access to the carbon-rich energy sources that underpinned the twentieth century’s complex urban

environments.24

This will require a revolution in energy use:

• At present, towns and cities account for 67% of the world’s energy consumption and 71% of energy-rela-

ted CO2 emissions.

• Assume business as usual, and urban emissions will grow by 55% over the next twenty years – equivalent

to double the US’s current emissions. Almost 90% of this growth will be in the developing world.

• Under this scenario, cities and towns in 2030 will be using 70% more coal, 60% more gas, and 35% more
oil than they are today. Fossil fuels would make up 85% of all urban energy use, virtually unchanged from

current levels.25

But the world we have described is one where such rapid emissions growth has been made impossible, where
fossil fuel use is below current levels, and where carbon constraints on trade will have changed the rela-

tionship between a city and its hinterland.26

By 2030, then, the future city will have substantially reconfigured its energy and transportation systems. It
will have found a way to house, feed and clothe a growing population using materials that have drastically

reduced levels of ‘embedded carbon’.27 And it will have set new standards for energy efficiency (low han-

ging fruit that have accounted for over a third of its decarbonisation).

4.8.2. The Feral City

So what are the prospects of the future city in this darker world?

The underlying demographic drivers, of course, will not have changed. Urban areas will see the same surge

in population (or perhaps an even greater one, given that poverty tends to keep birth rates high). But with the

global economy stagnating, people will no longer be pulled into cities by economic opportunity. Instead,
they’ll be pushed out of the countryside by disaster, war and famine.44

Worse still, new arrivals will often be moving to the wrong places. 13% of the world’s urban population lives

in coastal areas that are less than 10 metres above sea level.45 Today, there are over 3,000 cities and many

more smaller towns close to the waterfront – a figure that will have risen substantially by 2030.46 As sea le-
vels rise by a metre or so, Buenos Aires, Rio de Janeiro, Los Angeles, New York, Lagos, Cairo, Karachi,

Mumbai, Kolkata, Dhaka, Shanghai, Osaka-Kobe, Tokyo and thousands of smaller towns and cities will all

come under threat.47

By 2030, many, if not all, urban areas will have experienced a gradual intensification of their current vulnera-

bilities. Natural disasters reveal how fragile modern cities can be. Katrina shut down New Orleans, causing

$80 billion damage, and costing 1,836 lives.48 But by 2030, there’s a good chance that the US will have ex-

perienced its first $500 billion hurricane.49 The winds won’t need to be any stronger – poor planning and
pressure to build in vulnerable areas will have inexorably driven up the level of risk.

Nor does the breakdown of a city have to be so dramatic. In Europe, the heat wave of 2003 killed 35,000

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