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City of Smog: cleaning up Paris

December 2016 saw Paris become the world’s most aerially polluted city December 2016 saw Paris become the world’s most aerially polluted city Ioan Panait
28 Jan
As Paris continues to combat its severe air pollution problem, the compulsory displaying of car pollution certificates may be just the ticket

When Parisian mayor Anne Hidalgo took office in 2014, she did so with a promise to tackle the city’s air pollution blight. To help achieve this, she has proven herself keen to experiment with various urban transport schemes to reduce traffic emissions. These include introducing the Autolib electric car hire fleets, and pedestrianising the famous Champs-Élysées on the first Sunday of every month. Even so, in December 2016 Paris briefly became the world’s most aerially polluted city as airborne pollutants – particularly nitrogen oxides, fine particulate matter, unburned hydrocarbons, and carbon monoxide – built up across the city. These were especially concentrated in hotspots such as Victor Basch Square, or near Boulevard Périphérique – the city’s ring road. Emergency measures had to be taken to curb the damage, such as banning cars with odd or even number plates on alternate days, and making all public transport free to use.

The difficulty is we not only need to control particles, we also need to be able to control some of the gaseous emissions. The one that’s really challenging at the moment is nitrogen dioxide

Crit’Air, a new nationwide scheme, should aide Hidalgo in her quest to rid Paris of these pollutants. Adopting a system similar to the ‘traffic light’ labels that indicate the efficiency of our household appliances or the nutritional value of our food, it enforces the mandatory displaying of pollution certificates by almost all road vehicles travelling through France’s relatively new ‘low emission zones’ during normal weekday working hours. There are six different types of certificate available for low emitters, while older, more heavily polluting vehicles won’t qualify for a certificate at all. No label means no entry to the restricted parts of the city.

Gary Fuller, an air pollution scientist at King’s College London, points out that the French scheme is similar to one which has worked fairly effectively in Germany, at least in terms of curbing particle pollutants. ‘The difficulty is we not only need to control particles, we also need to be able to control some of the gaseous emissions,’ he explains. ‘The one that’s really challenging at the moment is nitrogen dioxide.’ To combat this, Paris is currently one of four cities – along with Athens, Madrid, and Mexico City – that recently declared it would become diesel-free by 2025, a move that would go a long way towards eliminating both harmful particles and gases from the city’s atmosphere.

This was published in the February 2017 edition of Geographical magazine.

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