Effect of Atmospheric Circulation on the Seasonal Dynamics of the Chemical Composition of the Snow Cover in the Pechora–Ilych Reserve

The layer-by-layer analysis of the variation dynamics of chemical parameters of snow at one of the observation sites (at the village of Yaksha) in the Pechora–Ilych state biosphere reserve in the winter of 2019–2020 has shown that the chemical composition of atmospheric precipitation is affected dominantly by long-range material transport. Features of the atmospheric circulation and the regions from which air masses are transferred control the saturation of the precipitation with certain chemical components. The calculation of the trajectories of reverse transport of air masses allowed us to identify regions where the air masses can be formed that come to the study area and carry material that potentially affects the chemical composition of the precipitation. The calculation of trajectories is demonstrated to make it possible to identify source regions of pollutants entering the atmosphere. This method of studying the chemical composition of snow is generally very informative and enables better understanding its formation factors.