Page 110 - A History of the World in 25 Cities

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Thousands of years ago, the first cities brought together large numbers of people, helping them to survive by sharing resources. Since then, cities have evolved into exciting places to live. People are
drawn to them because there are jobs, activities and lots and lots of other people. Today, cities around the world represent the best of humanity’s achievements, but also many of our failings.
Over the last 10,000 years, more and more people have been coming to live in cities.
By 1800, about seven people in every hundred lived in cities. Today, more than half of us live in them. By 2050, it is estimated that at least
two out of three people will be city dwellers.
Many of the cars, buses and lorries that keep today’s cities moving are driven by coal, oil
and gas – fossil fuels – which release carbon dioxide into the atmosphere. This extra
carbon dioxide created by the way we live is causing climate change.
The world’s temperature is rising, causing ice to melt at the North
and South Poles, making the sea level rise and creating extreme weather conditions.
Cities take up less than two per cent of the world’s land, yet they consume more than two thirds of its energy and produce more than 70 per cent of its carbon dioxide emissions. Now, and in the future, cities will need to change in order to help counter global warming.