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Seasonal and microscale variability of PM1 and PM10
Grégr, Michal ; Hovorka, Jan (advisor) ; Braniš, Martin (referee)
The master thesis evaluates the middle scale spatial/seasonal variability of PM1 and PM10 at four sampling localities. Statistical significant differences in PM values could be crucial for a representative placement of a measuring station at the locality. A set of 7 portable laser nephelometers DustTrak - DT (8520, TSI) was used to record 5 minute integrates of PM1 and PM10 consecutively for each size for 3 days at 4 localities. The localities were rural, urban, background and freeway and contrasted as far as the main aerosol sources are concerned. At each locality, inter-DT distances ranged from 30 - 500m, 80 - 220m, 70 - 150m, and 30m and total area covered 290 000 m2 , 57 000 m2 , 29 000m2 , 240m2 in rural, urban, background and freeway locality, respectively. Wilcoxon signed-ranks test for 2 dependent samples was used to evaluate the variability. As expected, PM1 did not vary statistically significantly (α=0.05) among DT's at all localities in both winter and summer. Contrary to PM1, inter-DT PM10 values varied significantly at background and rural localities, according to the Wilcoxon test. These differences occurred in 3 out of 50 possibilities for winter measurements. However, there is no statistically significant difference in median values comparison.
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Seasonal and microscale variability of PM1 and PM10
Grégr, Michal ; Hovorka, Jan (advisor) ; Braniš, Martin (referee)
The master thesis evaluates the middle scale spatial/seasonal variability of PM1 and PM10 at four sampling localities. Statistical significant differences in PM values could be crucial for a representative placement of a measuring station at the locality. A set of 7 portable laser nephelometers DustTrak - DT (8520, TSI) was used to record 5 minute integrates of PM1 and PM10 consecutively for each size for 3 days at 4 localities. The localities were rural, urban, background and freeway and contrasted as far as the main aerosol sources are concerned. At each locality, inter-DT distances ranged from 30 - 500m, 80 - 220m, 70 - 150m, and 30m and total area covered 290 000 m2 , 57 000 m2 , 29 000m2 , 240m2 in rural, urban, background and freeway locality, respectively. Wilcoxon signed-ranks test for 2 dependent samples was used to evaluate the variability. As expected, PM1 did not vary statistically significantly (α=0.05) among DT's at all localities in both winter and summer. Contrary to PM1, inter-DT PM10 values varied significantly at background and rural localities, according to the Wilcoxon test. These differences occurred in 3 out of 50 possibilities for winter measurements. However, there is no statistically significant difference in median values comparison.
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