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The thesis aims to determine the relationship between local air temperature and the isotopic composition of snow at Vostok Station in East Antarctica, and to reconstruct climate variability in the region over the past 200 years. Experimental data on isotopic composition and snow accumulation were obtained from 8 pits drilled at Vostok, with 2 covering the last 200 years. The meteorological regime is documented by instrumental observations and radiosonde data archived at the Arctic and Antarctic Research Institute. The study found that most precipitation in central Antarctica forms under "clear sky" conditions, and that the average condensation temperature at Vostok is close to the temperature of the upper limit of the inversion layer. The temporal variability of snow isotopic composition is influenced by the surface relief of the snow, and the seasonal variations of precipitation isotopic content follow local temperature variations. A significant linear relationship is observed between the mean isotopic composition of snow and air temperature near the surface over the past 40 years and multi-decadal timescales, but for shorter timescales (10 years), isotopic variations are dominated by source conditions. The study also suggests a climate teleconnection between central Antarctica and the tropical Pacific, with a 50-year fluctuation period in snow accumulation and isotopic composition similar to the Pacific Decadal Oscillation index.