ИСТИНА

Dynamics of the air pollution levels in Moscow city since 1957 till nowadays has been analyzed in details. As it is shown the annual-averaged concentrations of the sulfur dioxide was sharply (nearly two orders) decreased since 1957 due to use of fuel gas in urban heating instead of fuel oil since 1970s. Unlike SO2, the dynamics of nitrogen dioxide was complicated and non-monotonous like the sinusoidal function. The fall of NO2 in 1970s was followed later by its steady increase and, then, by total fall again since the end of 1990s. Probably, last fall was a result of gradual improvement of the traffic fuel quality. The carbon monoxide in general significantly decreased since 1966 till the beginning of 1990s. The concentrations of soot particles sharply decreased at the end of 1960s and later didn’t demonstrate clear changes during several decades. All the data in average of each separate month since 1957 were analyzed by use of spectral analysis. As it was found the annual course is clear for nitrogen dioxide and, as a rule, for sulfur dioxide. Both gases demonstrate clear maximum of spectral density with the period of one year (12 months). Unlike them, carbon monoxide and soot particles do not demonstrate clear annual periodicity. Besides, additional maxima of spectral density with periods usually from 2 to 9 years are an evident consequence of inter-annual variability. Nevertheless the statistical significance of this long periodicity remains doubtful.