Air Pollution in Cities
By Global Initiatives
Scientists have recognised the problem of air pollution in cities, and the accompanying risks to human health, for centuries – so why is it still a growing problem?
Industrial revolution to clean air resolution
London’s smoky pollution was known to cause deaths from respiratory problems as far back as 1273, when the use of coal was prohibited as being "prejudicial to health"
In December 1952 an estimated 4,000 Londoners died and 100,000 more were made ill as a result of what came to be known as ‘The Great Smog’. This event led to the Clean Air Act 1956, banning emissions of black smoke and requiring homes and factories to convert to smokeless fuels.
The US Air Pollution Control Act of 1955 and hundreds of similar regulations around the world have since sought to improve air quality by reducing or banning emissions of pollutants from manufacturing, energy generation and transport. Many of us now take it for granted that the air that we breathe every day is ‘clean’ and unlikely to kill us.
The return of smoggy cities
Despite all that legislation, recent years have seen the return of smog to many cities worldwide. The World Health Organisation (WHO) has concluded that air pollution is now a "public health emergency" across the globe.
More than a billion people live in communities that do not meet WHO air quality standards. A recent study in Nature showed that more people die from the effects of air pollution than malaria and HIV combined, including 1.4 million people a year in China, 650,000 in India and about 180,000 a year in Europe.
Worldwide, much of the pollution can be attributed to wood and coal burning or agricultural emissions, but traffic pollution is important in developed countries, causing a fifth of deaths. Globally, that death toll is likely to increase as car ownership is still rising.
Growing cities need a breath of fresh air
The urban population in 1960 accounted for just 34% of the total global population; in 2014 this had increased to 54%, a trend that is predicted to continue. By 2030, the largest three cities alone - Tokyo (37 million), Delhi (36 million) and Shanghai (31 million) - will be home to more than 100 million people. Many of the new urban dwellers will enjoy a higher standard of living and are expected to spend more of their disposable income on cars.
Some argue that we have reached ‘peak car’ – in the developed economies of Europe and North America, at least. But, with car ownership worldwide expected to triple to more than 2 billion privately owned vehicles by 2050, how can we prevent a growth in urban pollution from choking our cities?
On (or off) the road to a solution
Germany plans to put one million electric cars on the roads by 2020, with the cost set to drop under a new scheme to encourage more people switch to zero emission motoring. The economy minister wants to commit €2bn ($2.17bn) in government subsidies to support drivers buying electric cars.
But a slow, gradual switch to cleaner vehicles may not be enough. Mexico City’s Metrobús is a good example of long-term modal shift. Prior to its introduction in 2005, the average one-way commute was more than 2.5 hours, but segregated bus lanes have cut travel times almost in half. Many users now take Metrobús instead of private cars, preventing 150,000 car trips every day, and resulting in a reduction of 122,000 tons of CO2 emissions annually and considerably reducing other pollutants.
Perhaps the cities of the future should aim to minimise or exclude private cars altogether? The newly built Masdar City in Abu Dhabi was designed to exclude vehicles from the city centre, with cars restricted to parking around the perimeter. This principle was also successfully applied in the Vauban district of Freiburg, Germany, planned around green transport including trams, cycling and walking. 70% of the inhabitants live without a car, and residents who do own vehicles may park only on the edge of the district.
Is traffic pollution choking your neighbourhood? How might your city streets be reclaimed?
Should cities of the future aim to exclude private cars?
