Analysis of Surface Ozone Variations Based on the Long-Term Measurement Series in Krakow (1854-1878), (2005-2013) and Belsk (1995-2012)

One of the first long-term ozone measurement series in the world, as described in the chapter, was made in Poland (Krakow) during the period 1854-1878. The data obtained by the method of Schonbein papers reveal that annually averaged concentrations of ground level ozone in the second half of nineteenth century ranged between 11 and 24 ppb. For comparison, this chapter presents the results of contemporary measurements performed at rural background station in Belsk (1995-2012) and at urban background station in Krakow (2005-2013). Nowadays, annually averaged surface ozone values ranged between 22 and 31 ppb in Belsk and between 12 and 17 ppb in Krak6w. Seasonal variation of nineteenth century Krak6w series exhibited the highest surface ozone concentration during spring and early summer and the lowest in late autumn and winter. Current data present similar shape of distribution, although the sharp spring peak of high values has been replaced by a broad spring-summer maximum. Long-range averages of surface ozone concentration in rural areas are significantly higher than in urban areas (reaching 26 and 15 ppb, respectively).