Radiation Protection Dosimetry Advance Access published online on October 28, 2009
Radiation Protection Dosimetry, doi:10.1093/rpd/ncp225
MICROSCALE MODELLING SIMULATIONS FOR THE SITE CHARACTERIZATION OF AIR QUALITY STATIONS IN AN URBAN ENVIRONMENT
1 Arianet S.r.l., via Gilino 9, 20134 Milano, Italy
2 Agenzia Regionale per la Protezione dell'ambiente (ARPA) Piemonte, via Pio VII 9, Torino, Italy
* Corresponding author: g.tinarelli{at}aria-net.it
The presence of natural or artificial barriers placed near the air quality measuring stations located in an urban environment poses some problems in the assessment of their siting and significance. The atmospheric flow distortion induced by these structures can create situations that affect the concentration levels of measured pollutants. A modelling study at microscale of the pollutant dispersion in an urban environment has been performed to quantify these possible effects on measurements. The target domain is located in a central section of the city of Turin (northern Italy) around via della Consolata, near the location of an existing station of the regional monitoring network. The study involved the use of the modelling system Micro-Swift–Spray, which takes into account the presence of complex topographical barriers, including street canyons and squares surrounded by buildings. Two entire days have been simulated, to characterise both a critical and a more standard condition, with reconstruction of average flow, turbulence and hourly ground-level pollutant concentrations. Contributions from both traffic and building-heating sources have been considered and a comparison with measured concentrations has been performed to verify the representativeness of the measuring station with respect to both average conditions and spatial variability inside the considered region, otherwise very difficult to asses through a single and isolated measuring point.