What can cities do when air pollution soars and what works?
Earlier in January the London mayor and other organisations issued the first pollution warning of the year. These warnings follow the UK government index.
They are designed to protect vulnerable people, but they do this by asking those people who experience most harm to avoid doing things outdoors. They do not ask the polluters to reduce their emissions.
So, what can cities do when air pollution soars and what works?
Many European cities restrict car parking, reduce speed limits, pull the most polluting vehicles off the roads or ban half of vehicles according to odd/even number plates. These are usually balanced by cheaper, or free, public transport and cycle hire.
Most cities justify these schemes on the basis that traffic is a major source of air pollution, and any action must help.
Independent scientific evaluations are mainly restricted to the biggest cities. For example, data from Madrid and Paris shows that banning the most polluting vehicles can reduce traffic pollution by about 15-20%.
Many cities across the western half of the US ban home wood-burning when pollution is predicted to linger in the cold winter air. The scheme in Puget Sound, Washington issues bans each winter that typically last a few days but can be a week or more. In California’s San Joaquin Valley, wood-burning bans on around 100 days a year reduced hospital admissions for heart problems in elderly people by 7-17%. A pilot system has just begun operating in Sheffield in Yorkshire.
Some smogs cannot be controlled from within the city. Western Europe’s spring smogs and northern India’s pollution problems will require actions from surrounding farmers too.
The biggest smog reduction schemes are those around Beijing. These began with the 2008 Olympics and
Read more on theguardian.com
