The paper presents the results of the microscopic analysis of solid precipitation (snow) sampled from three key areas located in neighboring nival-glacial systems at the beginning of the cold period in 2019-2020 (November, December). Pollen of Pinus sp., Betula sp. belonging to Asteraceae, Chenopodiaceae, Poaceae families was found in the snow samples. The samples collected simultaneously from three key area on December 7, 2019 displayed 4 taxa out of 5 identified during the entire analyzed period as well as territories which pollen could be transferred from were identified. According to the backward air-mass trajectories calculation (HYSPLIT model), the analysis of constant pressure maps and snow distribution maps, these territories were located to the south of the key testing sites.
To assess the possibility of atmospheric supply of microplastics in the south of Western Siberia, integrated snow cover samples at two test sites were taken. In this study, snow cover was considered as an accumulator of atmospheric precipitation during the cold period. The use of Scanning Electron Microscope (SEM S-3400N Hitachi Science Systems Ltd, Japan) allowed to visually detect particles and fibers in the obtained samples that were previously identified as microplastics. To confirm that the detected particles are microplastics, the elemental composition of the same samples was analyzed using energy-dispersive spectrometry for the scanning electron microscope (XFlash 4010, Bruker AXS Microanalysis GmbH, Germany). This method also showed that the detected particles and fibers are microplastics.
In order to validate the isotopic models of the general circulation of the atmosphere ECHAM5-wiso and ECHAM6-wiso, modeling in nudging mode was made. These model data were compared with experimental data on the isotope composition (δHDO and δH218O) of precipitation for stations in the foothills of Altai mountains (52.596° N, 85.25° E) created and maintained by the Institute for Water and Environmental Problems SB RAS.
The estimation of precipitation change in the Altai (1959-2015) was carried out using the Mann-Kendall-Sneyers test. It was found that the variation of precipitation has a step change point occurred in 1980. During the first interval (1959- 1980), the trend was mostly positive, whereas during the second interval (1981-2015) it was constantly negative. The step change point of precipitation in the Altai coincides with the beginning of the «Zonal epoch Elementary Circulation Mechanisms – ECM» for Siberian sector according to the Dzerdzeevskii classification. To clarify the role of various ECM in the Altai precipitation, we calculated the contribution of the ECM, which correspond to Siberian sector, into the changes of precipitation trends. It was found that the most significant contribution into the change of precipitation regime in the Altai was provided by the «West zonal and Southern meridional» Circulation group.