A measurement campaign in a street canyon in Helsinki and comparison of results with predictions of the OSPM model |
| |
Institution: | 1. Finnish Meteorological Institute, Air Quality Research, Sahaajankatu 20 E, FIN-00810 Helsinki, Finland;2. Helsinki Metropolitan Area Council, Opastinsilta 6 A, FIN-00520 Helsinki, Finland;3. National Environmental Research Institute, Frederiksborgvej 399, DK-4000 Roskilde, Denmark;1. Centre for Agricultural Water Research in China, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China;2. China Water & Power Press, Beijing 100038, China;3. China Institute of Water Resources and Hydropower Research, Beijing 100044, China;1. Estonian Crop Research Institute, Department of Agrotechnology, J. Aamissepa 1, Jõgeva, Estonia;2. Tallinn University of Technology, Institute of Marine Systems, Ehitajate tee 5, 19086 Tallinn, Estonia |
| |
Abstract: | In 1997, a measuring campaign was conducted in a street canyon (Runeberg St.) in Helsinki. Hourly mean concentrations of CO, NOx, NO2 and O3 were measured at street and roof levels, the latter in order to determine the urban background concentrations. The relevant hourly meteorological parameters were measured at roof level; these included wind speed and direction, temperature and solar radiation. Hourly street level measurements and on-site electronic traffic counts were conducted throughout the whole of 1997; roof level measurements were conducted for approximately two months, from 3 March to 30 April in 1997. CO and NOx emissions from traffic were computed using measured hourly traffic volumes and evaluated emission factors. The Operational Street Pollution Model (OSPM) was used to calculate the street concentrations and the results were compared with the measurements. The overall agreement between measured and predicted concentrations was good for CO and NOx (fractional bias were ?4.2 and +4.5%, respectively), but the model overpredicted the measured NO2 concentrations (fractional bias was +22%). The agreement between the measured and predicted values was also analysed in terms of its dependence on wind speed and direction; the latter analysis was performed separately for two categories of wind velocity. The model qualitatively reproduces the observed behaviour very well. The database, which contains all measured and predicted data, is available for further testing of other street canyon dispersion models. The dataset contains a larger proportion of low wind speed cases, compared with other available street canyon measurement datasets. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|