Ground Level Ozone Concentrations in the Kraków Region, Southern Poland

Abstract

Concentrations of tropospheric ozone were measured from June to mid-October 1995 at 18 localities in the Kraków Province of southern Poland. Both active and passive measurements were made by using UV monitors and Ogawa passive samplers, respectively. At the active monitoring stations measurements were made in the downtown and western part of Kraków and in Szarów, 30 km east of the city. Passive samplers were used at 18 sites within and outside the city limits. In addition, ozone bioindicator tobacco plants ( Nicotiana tabacum L., Bel- W3 and Bel-B) were also exposed to ambient air at the sites with passive samplers. In the Kraków Province, the mean 24-h ozone concentration (from active monitors) was higher than 30 μg m −3 (24-h Polish standard) in June through July and part of September. The highest concentrations occurred in the early afternoon, and concentrations were lowest between midnight and sunrise. The 30-min maximum concentration of 205 μg m −3 occurred in August. However, great diversity of tropospheric ozone concentrations (measured with passive samplers) were recorded in all locations. The lowest average concentrations were recorded in Kraków and in areas located west, northwest, and east of the city, whereas the highest average concentrations were recorded in the north, northeastern, southeastern, and southwestern parts of the Province. The highest average concentration of 100 μg m −3, for a 2-week filter exposure, was recorded in July and August at the sites located 40 km south (Ratanica), and 25 km north (Goszcza) of Kraków . The amount of damage to leaves of the ozone-sensitive variety of tobacco (Bel-W3) exposed at all sites was correlated with concentration measurements obtained with passive samplers (coefficient 0.69, p<0.0001). More damage was recorded at the sites located outside the city than at sites within Kraków.