Variations of the carbon monoxide total column and parameters of the atmospheric boundary layer in the center of Moscow

The content of carbon monoxide in the atmosphere over Moscow has been measured from the absorption spectra of solar radiation in the infrared spectral range (2153–2160 cm−1) for the period 1993–2007. A main advantage of the method is a virtual independence of the results averaged over a significant space and atmospheric thickness on local and even relatively large-scale pollution sources. Moreover, the method permits the determination of the characteristics of anthropogenic pollution of the city air by CO by comparison of the measurement of CO content in two observation sites (one is in the city center and another is outside the city). In both the cases, diffraction spectrometers with the resolution 0.2 cm−1 supplied with a sun tracking system were used. From 2005, in the center of Moscow, the parameters of the atmospheric surface layer have continuously been measured using a LATAN-3 acoustic locator. The measurements show that in this period (14 years), the CO content within an air layer polluted by the city did not increase in spite of the threefold increase in the number of automobiles in the city. Thus, the method allows one to determine the trend of air pollution above Moscow. Variations of the CO content are mainly determined by the wind velocity and the presence of temperature inversions. Using the results of the acoustic sounding, a relation between the pollution magnitude and the condition of the impurities has been elucidated. The wind velocity in the surface (to 500 m) layer has the greatest effect on the pollution accumulation in the city atmosphere. For cold and warm seasons, the correlation coefficients of the urban proportion of the CO content with the wind velocity averaged over air layers of various heights are found. © 2009, Pleiades Publishing, Ltd.