ИСТИНА

The study is aimed to the estimation of applicability and precision of a methodology for identification of the background concentration of ozone. These values are necessary to estimate a maximum permissible emissions value, to understand the health risk level for the population and to evaluate the activity of ozone sources (first of all man-made). Currently applied state-approved methods have some limitations, thus the application of a new methodology based on the time variations of impurity concentration is of research and practical interest. Research objects are concentrations of tropospheric ozone in Moscow (anthropogenic polluted atmospheric air, mostly because of the transport activity) and in the settlement with relatively low pollution level. Initial data are results of the continuous records of concentrations of ozone, it’s precursors and meteorological parameters from the ozone monitoring network. The methodology tested in this study to identify a background ozone concentration is the dynamic phase portrait method, considering variations of changes concentration during the time. The value obtained presents the concentration of tropospheric ozone most characteristic for the studied location. The background concentrations value obtained using the tested methodology are in the more accordance with the values calculated using the state-approved methodology, the longer the observation period is. The values identified make it possible to take into account the peculiarities of the distribution of pollutants and the complex of meteorological factors in a particular territory and to abandon the use of standard values assigned.