For the first time in history, more than half the world's population live in cities: by 2030, three out of five people will be city dwellers. But the British are bucking this trend. The 2001 census revealed an "exodus from the cities". Since 1981, Greater London and the six former metropolitan counties of Greater Manchester, Merseyside, South Yorkshire, Tyne and Wear, West Midlands and West Yorkshire have lost some 2.25 million people in net migration exchanges with the rest of the UK; in recent years this trend has accelerated.
This is not sustainable. British people need to be cured of the insidious fantasy of leaving the city and owning a house in the country: their romantic dream will become a nightmare for people elsewhere on the planet.
The fact is that rural households have higher carbon dioxide emissions per person than those in the city, thanks to their generally larger, detached or semi-detached houses, multiple cars and long commutes (cars are responsible for 12 per cent of greenhouse gas emissions in Europe - 50 per cent in some parts of the US). The regions with the biggest carbon footprints in the UK are not the metropolises of Glasgow or London, but the largely rural northeast of England, as well as Yorkshire and the Humber. In fact, the per capita emissions of the Big Smoke - London - are the lowest of any part of the UK.
To create a low-carbon economy we need to become a nation of city dwellers. We tax cigarettes to reflect the harm they do to our health: we need to tax lifestyles that are damaging the health of the planet - and that means targeting people who choose to live in the countryside. We need a Rural Living Tax. Agricultural workers and others whose jobs require them to live outside cities would be exempt. The revenue raised could be used to build new, well-planned cities and to radically upgrade the infrastructure of existing cities.
We have an opportunity to create an urban renaissance, to make cities attractive places to live again - not just for young adults, but for families and retired people, the groups most likely to leave the city. Turning our old cities into "smart cities" won't be easy or cheap, but in a recession this investment in infrastructure will boost the economy. We need to learn to love our cities again, because they will help us to save the planet.
P. D. Smith is an honorary research associate in the Science and Technology Studies Department at University College London and author of Doomsday Men: The Real Dr Strangelove and the Dream of the Superweapon (2008). He is writing a cultural history of cities. www.peterdsmith.com
in WIRED, PD Smith