Parisians curious about the quality of the air they're breathing will soon be able to get their daily fill by looking to the sky. A balloon that's been floating above the city's André-Citroën park since 1999 will be modified by its creators, Aérophile, to monitor the level of air pollution on an hourly basis starting in early 2008.
The colors will range from green - signifying an excellent air quality - to (you guessed it) red - signifying a very poor air quality (orange will represent a "mediocre" air quality). The balloon will be equipped with two light systems reflecting two different pollution indices: One, located within it (and visible by night), will measure the city's ambient air quality while another (powered by electroluminescent diodes), situated at the base of the balloon, will keep tabs on the air pollution produced by auto emissions - which will be visible both by day and night. Airparif, an organization in charge of monitoring the air quality in various French cities, will be recording the data on its website, alongside that of 30 other European cities.
Via ::Le Monde: Un ballon mesurera la pollution de l'air de Paris (newspaper)