| Autor: |
Röösli, Martin1 Martin.Roeoesli@unibas.ch, Braun-Fahrländer, Charlotte1, Künzli, Nino1, Oglesby, Lucy1, Theis, Gaston2, Camenzind, Markus2, Mathys, Patrick3, Staehelin, Johannes4 |
| Předmět: |
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| Zdroj: |
Journal of the Air & Waste Management Association (Air & Waste Management Association). Jul2000, Vol. 50 Issue 7, p1115-1124. 10p. 4 Charts, 5 Graphs. |
| Abstrakt: |
The spatial variability of different fractions of particulate matter (PM) was investigated in the city of Basel, Switzerland, based on measurements performed throughout 1997 with a mobile monitoring station at six sites and permanently recorded measurements from a fixed site. Additionally, PM[sub10] measurements from the following year, which were concurrently recorded at two urban and two rural sites, were compared. Generally, the spatial variability of PM[sub4], PM[sub10], and total suspended particulates (TSP) within this Swiss urban environment (area = 36 km²) was rather limited. With the exception of one site in a street canyon next to a traffic light, traffic density had only a weak tendency to increase the levels of PM. Mean PM[sub10] concentration at six sites with different traffic densities was in the range of less than ± 10% of the mean urban PM[sub10] level. However, comparing the mean PM levels on workdays to that on weekends indicated that the impact of human activities, including traffic, on ambient PM levels may be considerable. Differences in the daily PM[sub10] concentrations between urban and more elevated rural sites were strongly influenced by the stability of the atmosphere. In summer, when no persistent surface inversions exist, differences between urban and rural sites were rather small. It can therefore be concluded that spatial variability of annual mean PM concentration between urban and rural sites in the Basel area may more likely be caused by varying altitude than by distance to the city center. [ABSTRACT FROM AUTHOR] |
| Databáze: |
GreenFILE |
| Externí odkaz: |
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