Sound and vision

摘要

I'm swooping down the boulevards of Paris in a virtual simulation of the city of light, where sound levels are depicted as colour. The deep blue roar of traffic washes along the streets, blazing crimson against the base of adjacent buildings, fading to orange and gold further up the facades where the noise is fainter. Orange flares of traffic echo gush down side streets, giving way to gentle shades of green in the quiet rues and parks beyond. I'm exploring one of the world's first three-dimensional (3D) computer maps of urban decibels ― you might call it the city of noise. This map hails from abank of computers in an office of the Paris city government, and is one of the most sophisticated around. Other cities are developing their own as part of a European Union (EU) plan to tackle noise pollution. Legislation passed last year requires member states to make, by 2007, regular noise maps of all major cities, roads, railways, airports and industrial sites. These maps are a powerful new way to visualize noise pollution. Some 80 million Europeans suffer noise levels that can cause stress, sleep loss, high blood pressure and even heart attacks, according to the European Commission. Another 170. million endure noise that is just annoying.