Environ Monit Assess (2011) 172:215–223 DOI 10.1007/s10661-010-1328-4 The design of long-term air quality monitoring networks in urban areas using a spatiotemporal approach Farhad Nejadkoorki · Ken Nicholson · Kamal Hadad Received: 1 July 2009 / Accepted: 17 January 2010 / Published online: 6 February 2010 © Springer Science+Business Media B.V. 2010 Abstract The implementation and maintenance of an air pollution monitoring program can be ex- pensive and time consuming, especially when the aim is for long-term monitoring over a significant area. Consequently, it is essential that sites are optimized to provide the best representative cover while minimizing costs. In the past, there has been a tendency to locate sampling stations at pollution hot-spots. While this is acceptable for determin- ing a maximum potential exposure or identifying the extent of a risk, there are limitations to this approach when assessing the potential impact of any future abatement strategies or determining the level of exposure outside the vicinity. This paper presents an approach in which represen- tative air quality assessments can be undertaken F. Nejadkoorki (B ) Department of Environmental Engineering, Yazd University, Yazd, Iran e-mail: f.nejadkoorki@yazduni.ac.ir K. Nicholson Nicholson Environmental, The Cottage, Victoria Road, Quenington, Cirencester, Gloucestershire GL7 5BW, UK e-mail: ken@nicholson-environmental.co.uk K. Hadad Faculty of Engineering, Shiraz University, Shiraz, Iran e-mail: hadadk@shirazu.ac.ir for an urban area using the minimum number of measurement sites. A novel methodology is described that involves site selection to capture the maximum variance in measured pollutants, while minimizing spatiotemporal autocorrelation between the selected sites. A case study is pre- sented for Yazd, Iran. Overall, the results show that the proposed methodology can be effective and enable the long-term monitoring of air pollu- tion to be undertaken on a cost-effective basis in urban areas. In addition, there is the potential for the methodology to be utilized for other forms of pollution (e.g., water, soil, and noise). Keywords Air pollution · ArcGIS · Spatiotemporal · Monitoring network · Urban areas Introduction Increasing concerns about the health effects of air pollution have underlined the need for regulatory authorities to monitor and assess pollution levels, especially in urban areas. In many cases, there is a statutory requirement to provide a quantitative assessment, so that air quality objectives can be shown to be achieved or so that any need for abatement strategies can be identified. The opti- mization of any monitoring network is highly desirable, since this enables it to meet these