Paris, along with several other cities in northern France, is in the midst of a multi-day air pollution crisis, with pollutants hovering at dangerous levels. In response to the pollution, authorities have waived fees on Paris' extensive public transportation system in a bid to discourage car use.
A persistent area of high pressure is causing the smog — it is effectively putting a lid on the atmosphere over Paris and northern France, promoting sinking air and light winds. Such conditions have trapped pollutants at low altitude, cloaking Paris' elegant city scape in a milky haze. The pollution is a risk to human health, since certain forms of atmospheric particles can seep into the lungs and cause a variety of health hazards, particularly among the young, elderly, and others with compromised immune systems.
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The smog stretches from the west coast of France, across Paris, and northeastward to Belgium and parts of Germany. According to the Associated Press, this is the worst such event in Europe since 2007.
The New York Times reported the French government is promoting bicycle sharing programs and the use of clean electric cars through the weekend in an effort to curb the pollution that is creating the smog. In addition, authorities have lowered the speed limit on roadways, and reportedly issued more than 10,000 tickets on Thursday alone.

The Eiffel Tower and the Beaugrenelle district, right, are seen through the smog in Paris, Thursday March 13, 2014, as pollution over the French capital is at high levels. In an official effort intended to curb air pollution, Paris Town Hall announced that residential parking, will be free Thursday, to encourage drivers to leave their cars at home and take public transportation.
Image: Remy de la Mauviniere/Associated Press
Based on weather forecasts, it appears the pollution troubles will last through Saturday, but a cold front sweeping down from England may stir things up enough to clear some of the pollution out on Sunday. High pressure located west of France early next week may bring renewed air quality problems, however, especially if it drifts eastward and winds remain low.
According to the Times, the European Commission has repeatedly warned France that it is out of compliance with European air pollution guidelines.