Spatial Correlation of Automatic Air Quality Monitoring at Urban Background Sites: Implications for Network Design

Measurements of carbon monoxide, nitrogen oxides, PM10, sulphur dioxide and ozone from four UK National Automatic Urban Network Stations have been analysed for the year 1994. All of the sites are urban background, with two in the same city (Birmingham Centre and Birmingham East) and the other two also in cities in the centre of England, Leicester and Leeds, respectively 58 and 154 km from Birmingham. Expressed as cumulative frequency distributions and median concentrations, the pollution climates of the four sites are relatively similar, with differences between Birmingham Centre and Birmingham East as large as those between Birmingham and the other cities. Sulphur dioxide, which does not have an appreciable road traffic source, behaves differently, especially in Leeds, which is adjacent to a number of major point sources. However, when monthly hourly maxima and exceedences of health-related threshold concentrations are examined, the sites behave differently and relationships between them are much poorer,...