Concentrations of volatile organic compounds in surface air along the trans-Siberian railroad

In recent decades, changes in the atmospheric composition have been revealed not only over industrialized countries but also over remote regions of the globe. In particular, the atmospheric concentration of volatile organic compounds (VOCs) has increased as a result of the activity of the chemical industry, fuel combustion, storage and recycling of waste products, and other kinds of human activities. In this work, the results of VOC monitoring in the atmospheric surface layer along the Moscow-Vladivostok Trans-Siberian Railroad are given. The measurements were performed in the framework of the Russian-German TROICA (Trans-Siberian Observations of the Chemistry of the Atmosphere) experiments by using a mobile laboratory. This is the first-ever set of transcontinental measurements performed from a mobile laboratory. The measurements allow us to determine the seasonal peculiarities in the VOC distribution over the continent and to identify the regions characterized by continuously enhanced VOC contents. An analysis of the results makes it possible to reveal the peculiarities in the distribution of toxic chlorine substances, the influence of biomass burning on VOC contents in rural areas, and the transboundary transport of minor gaseous atmospheric impurities from other countries.