The larger, the better (en)

The larger, the better, is the solution for sustainablity passing by the megacities?

Civilisation, that great loaded descriptor of human society, originates with cities. They have grown from the once vast Nineveh – home to 120,000 people in the ancient Assyrian Empire in 650 BC – to the Anthropocene’s megacities, defined as having more than 10 million inhabitants. There are currently almost 30 megacities on the planet (there were just three in 1975) – with the Tokyo metropolis, Japan’s national capital region, hosting over 35 million people at a population density more than double that of Bangladesh. By 2050, these megacities are expected to merge into dozens of megaregions, like Hong Kong-Shenhzen-Guangzhou in China, with more than 100 million people living in an endless city skyline.

The denser the city, the more productive, efficient and powerful it becomes. The theoretical physicists, Luis Bettencourt and Geoffrey West calculated that if the population of a city is doubled, average wages go up by 15%, as do other measures of productivity, like patents per capita. Economic output of a city of 10 million people will be 15-20% higher than that of two cities of 5 million people. Incomes are on average five times higher in urbanised countries with a largely rural population. And at the same time, resource use and carbon emissions plummet by 15% for every doubling in density, because of more efficient use of infrastructure and better use of public transportation.

The urban revolution of the Anthropocene could prove to be the solution to many of our environmental and social problems, allowing humans to inhabit the planet in vast numbers, but in the most sustainable way.

BBC - Future - Science & Environment - Sustainability in the new urban age