Relationship of total ozone amount, UV radiation intensity, and the ground-level ozone concentration at rural Lithuanian sites

The ultraviolet radiation intensity, the total ozone amount, and the ground-level ozone concentration are the three essential factors having impact on the vegetation, materials, the human health, and the atmospheric chemistry. The analysis of the relationship among these parameters was made for the obtained data under Lithuanian rural conditions. UVB radiation intensity and ground-level ozone concentration were measured at the Rugesteliskes monitoring station and total ozone data were obtained from the Kaunas meteorological station during 2002-2003. Cloudless or slightly cloudy days of the period were chosen for the analysis. The results showed a strong dependence (R = 0.73 for 2002 and R = 0.75 for 2003) between the UVB radiation intensity and the ground-level ozone concentration. The photochemical ozone generation at the Rugsteliskes station, located in the unpolluted forest area, is related to the reaction between natural volatile organic compounds emitted from the vegetation at low nitrogen oxide level. A more pronounced relationship between the UVB radiation intensity and the ground-level ozone concentration was found in 2003 and it could be related to specific meteorological conditions of the summer of 2003. A negative correlation (R > -0.86) was determined during cloudless days between the UVB radiation and the total ozone.