Air quality and CO emissions in the Moscow megacity

• Information about Moscow population, territory and meteorology is given.
• High quality data were used for air pollution index and CO emission estimation.
• CO emissions calculated from: (1) CO surface concentrations and (2) CO total column data.
• New results revise some former estimations of air pollution in Moscow megacity.
• Moscow is a moderately polluted megacity.

Moscow with a population of 12.1 million people is the largest city in Europe. An up-to-date monitoring network organized in Moscow in the early 2000’s has made it possible to estimate air quality and the concentrations of key pollutants emitted into the atmosphere. In this work, air-quality estimates obtained earlier were corrected using new observational data. As a result, Moscow ranks among clean megacities in the world. The emissions of CO were calculated on the basis of data on the surface concentration, vertical profile, and total column of CO. The surface concentration of CO was measured at 25 stations uniformly spaced on the territory of Moscow. The vertical profiles of CO were measured at the Ostankino TV tower. Data on the CO total column were obtained from long-term measurements using infrared solar absorption spectroscopy at two sites located in the center of Moscow and in Zvenigorod (53 km to the west of the center of Moscow). The annual emissions of CO from the Moscow megacity were estimated at 870 ± 200 Gg yr−1 for 1992–2008 and 680 ± 160 Gg yr−1 for 2002–2008. These values are slightly lower than those given for Moscow in the global inventories EDGAR and IPCC-AR-4.