Paris' novel way of allowing its residents, officials and tourists to easily survey the city's
air quality levels - a giant colour-changing balloon - has been reintroduced for 2009.
Air quality monitoring firm Aerophile constructed the helium balloon, which changes colour depending on the cleanliness of the Parisian air, reports mnn.com.
Holidaymakers and residents of the city will be able to see fluctuations in
air quality brought about by aspects such as traffic pollution, as marked by the colour changes in the balloon. It is designed to detect levels of three different types of pollutant - nitrogen dioxide ozone and airborne particles.
The balloon also has an interactive element - up to 30 passengers a time can climb into its basket for a view of the city, while those with internet access can watch a webcam attached to the device.
Aerophile was established in 1993 by two 25-year-old engineers in France who were aiming to reinvent the hot air balloons for a variety of uses.