Site description and equipment Results and discussion THE RESULTS OF LONG-TERM MONITORING OF SURFACE OZONE CONCENTRATION NEARBY TOMSK B. D. Belan, D. K. Davydov, D. E. Savkin, T. K. Sklyadneva, G. N. Tolmachev, A. V. Fofonov V.E. Zuev Institute of Atmospheric Optics, SB RAS, Tomsk, 634055, Russian Federation (bbd@iao.ru, +7(3822)492-086) Introduction Results Introducion The ozone content in the troposphere is substantially influenced by human activity. Atmospheric emissions of nitrogen oxides (NOx), carbon oxides (CO and CO2), methane (CH4), and different organic compounds promote ozone formation in polluted air and increase the ozone concentration in the troposphere as a whole [1]. Since ozone is the strongest oxidant and a greenhouse gas, an increase in its content in the atmosphere has an adverse effect on living matter and climate [2]. At high concentrations it strongly inhibits vital activity of plants and negatively affects the human. In this paper we present the results of the long-term ozone monitoring carried out in the atmospheric surface layer nearby Tomsk. Data are presented on the daily, annual and long-term behavior of the surface ozone concentration (SOC). It was found that SOC in the region under study often exceeds hygienic regulations for a daily average and one-time maximum permissible concentration as well Annual variations The annual mean behavior presented in Fig. 4 is not always observed. For the last period of observations we can distinguish four types of annual variation for the region under study, which are presented in fig. 5. Aim Observational data on the surface ozone concentration (SOC) between 1990 and 2015 obtained at the, Russian Academy of Sciences, are presented. Characteristic features of the temporal variability of the surface ozone concentration are studied Fig.4 Annual mean behaviour and monthly mean variations of SOC averaged over the whole measurement period (1992-2015). Site description and equipment Data from a TOR-station (56°28'41'‘ N, 85°03'15'' E) are used for analysis. This is an automatic station located in the north-eastern outskirts of the Academic City (Akademgorodok) of Tomsk in the building of a high-altitude atmospheric sounding station at the V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Sciences (IAO SB RAS). There are no industrial objects or motorways near the station, and the effects of local gas and aerosol sources are decreased. The station is located in the zone of boreal forests and surrounded by small deciduous and coniferous forest stands. Fig.5.Types of annual variation of SOC observed in Tomsk. Long-term annual vaiations Fig. 6 presents the annual average of its content in the atmospheric surface layer, which was calculated for the whole period from 1990 to 2015 Equipment Fig.6. Long-term annual behaviour and yearly mean variations of SOC. Performance of hygienic regulations JSC OPTEC 3.02 P-A Ozone analyzer TEI model 49c 1-500 µg/m3 Measure range Low 0-0,2 ppm High 0-0,5 ppm ±20% Accuracy ± 0,5% of F. S. (Full scale) Russia Place of Origin USA Chemiluminescence Method UV Tab.1. Repeatability of exceeding the maximum permissible concentrations of SOC YEAR 1MPCd.a 2MPCd.a 3MPCd.a 4MPCd.a 5MPCd.a MPCone-time 1990 17.8 0.7   1991 46.6 27.6 9.2 0.6 1992 51.6 18.7 9 3.5 2.1 1.77 1993 67.8 22.3 4.2 1994 48.6 13.7 1.1 0.3 1995 28.8 1996 45.1 11.6 2 1997 47.2 7.1 1998 0.8 1999 10.8 2000 31.42 6.56 2.19 2001 58.63 27.40 9.59 1.64 1.10 0.82 2002 50.41 13.97 2.74 0.55 2003 60.55 16.16 1.92 2004 57.92 12.84 3.28 2005 46.03 14.52 2006 36.44 17.53 2007 56.99 2008 56.28 6.01 2009 55.62 11.23 0.27 2010 55.89 5.75 2011 52.60 13.42 2012 42.62 7.10 2013 39.18 6.03 2014 63.84 19.45 2.47 2015 67.67 21.10 3.84 Results and discussion Diurnal variations Fig.7. Distribution of different values of SOC over the whole measurement period (1992-2015). Fig. 7 shows that more than half of the values have a magnitude lower than the MPC settlements. Tab. 2 demonstrated that the region is regularly exceed hygienic regulations as for a daily average so maximum one-time limit admissible concentration. Acknowledgements This work was funded by Russian Foundation for Basic Research (grant №14-05-00590), and Ministry of Education and Science of Russia (State Contracts №14.604.21.0100 (ID:RFMTFIBBB210290), №14.613.21.0013 (ID: RFMEFI61314X0013)). Fig.2. Diurnal behaviour of SOC averaged over the whole measurement period (1990-2015). Fig. 3. Diurnal behaviour of SOC averaged for the middle months of each season.(1990-2015) Reference Crutzen, P.J. and Zimmermann, P.H., The Changing Photochemistry of the Troposphere, Tellus A, B, 1991, vol. 43, pp. 136-151. Scientific Assessment of Ozone Depletion: 1998, WMO Global Ozone Research and Monitoring Project Report, Geneva, 1999, no. 44. The diurnal amplitude of SOC variation depends on the season, that can be seen from fig. 3.