New map to help city deal with noise

A “NOISE map” has been developed by the Shanghai Academy of Environmental Sciences to help track and control noise pollution.

On the map, each city block and major street within the Outer Ring Road is colorcoded to represent different average noise levels. Busy roads can average between 60 and 80 decibels, while areas near parks can rate between 30 and 35 decibels.

According to Zhou Yude, director of the academy’s noise control engineering research center, the mapping project started about six years ago and the map is still being tested and improved.

Data for the map is gathered directly via noise detectors, as well as indirectly though data from transportation authorities.

“For roads that are not equipped with detectors, we collect data from transport authorities, including traffic volume, car speed as well as car model,” said Zhou.

According to Zhou, the map updates every 20 minutes, giving researchers a picture of how noise levels fluctuate throughout the day across the city.

Noise maps have been developed in Europe, as well as Japan and South Korea, for environmental protection and urban planning purposes. In some cases though, these maps are infrequently updated.

“The updating rate of a noise map is decided by how we use it,” said Zhou. “In European countries, the maps are usually used for longterm environmental policy making and urban planning. But for a city like Shanghai which is still developing at a fast pace, noise data changes quickly with on-going city construction. Different months or seasons can have very different maps.”