Paris has come up with a new measure to fight smog on particularly bad-air days: Remove the cars that make the smog.
When air quality takes a dive, cities have various emergency options to relieve the problem. These short-term fixes include telling people to stay at home or leave town (London’s most recent gambit), cutting speed limits, or reducing ticket prices for public transport. Some cities also ban half of cars from entering the center, based on odd and evenly numbered car license plates, although that doesn’t work so well long-term, as better-off people game the system by making sure they have both odd and evenly numbered vehicles.
Paris, though, has a unique weapon against smog. France issues air-quality certificates, based on the age of a car, and the kind of fuel it uses. These certificates are optional in France as a whole, but mandatory in Paris. This certificate made it possible for Paris to ban all cars made before 1997 from its center last summer, but it also comes in handy for smoggy days. According to the Guardian, last week Paris banned diesels over 16 years old.
These fixes can help out in an emergency, but the only way to reduce pollution in cities to any meaningful extent is to reduce cars permanently. Paris is already at the front of this race, removing traffic from its busiest streets, redesigning intersections to favor pedestrians, and holding regular car-free days.
That’s not enough, but it’s a lot better than other cities are managing. One day, we might look back on cars in cities as analogous to the times when Londoners would dump sewage from a bucket straight into the streets, and pedestrians would have to pick their way carefully across the road.