Multiscale Analysis of NO2 Pollution Index during Recent 8 Years in Shanghai

By wavelet analysis of daily NO₂ pollution index in recent 8 years in Shanghai, the result shows that periodical oscillation of NO₂ pollution index varies under different time-scales; the spring and autumn is the shift between lower and higher pollution under the scale of quasi year; the air pollution pattern of Shanghai presents ldquoserious in winter and slight in summerrdquo at most scales. Though NO₂ Pollutions are influenced not only by meteorological conditions, but also by growth of energy demand and socio-economic development, Shanghai made air pollution declined faintly due to great efforts on treatment of environmental pollution.