Variability of the stages of sea ice development in the Laptev Sea is assessed with 10-days periodicity for the autumn — winter period on a basis of AARI digital ice charts for 1997–2017. Difference in formation of the stages of ice development (ice thickness) was revealed between the drifting and fast ice, which is manifested in an earlier appearance of the first-year ice for the fast ice area and in its partial concentration. On average, the ice cover of the Laptev Sea is by 60 % composed of thick first-year ice, most of which is formed within the fast ice area — 38%, while the area of drifting ice is 1,5 times larger.

The paper presents the scheme of the anthropogenic radioactive pollution of Russian Arctic and describes the main principles of its compilation. The scheme shows the main polluted onshore and offshore areas and defines the supposed sources of the pollution.

The water level characteristics calculated for hourly observations and observations at 4 and 2 times per day at the Yamsal Bar, Novy Port, Seyakha, Tambey, Drovyanaya, and Antipyuta were compared. Presented discrepancies (differences) between observations of different discrete for the average daily, average monthly, average annual and extreme level. It is shown that the greatest discrepancies between hourly observations and observations in 4 terms in determining the average daily levels reach 8–33 cm, the average monthly — 1–3 cm, the average annual — close to zero, extreme — 32–78 cm. The greatest discrepancies between hourly observations and observations in 2 terms in determining the average daily levels reach 21–96 cm, the average monthly — 4–27 cm, the average annual — 2–3 cm, extreme — 60–177 cm.

The difficulty of ice conditions and their impact on various marine applications are mainly related to fluctuations in ice massifs areas that are subject not only to interannual, but also to climate variability. The article presents for the first time the analysis of the areas of the Kara Sea ice massifs in the summer during for the “cold” (1954–1985) and “warm” (1986–2017) climatic periods in the Arctic. The typical changes in ice massifs areas and frequency of their absence in different climatic periods can be used to characterize the predicted type of ice conditions in the Kara Sea.

The article presents the results of a study of the temporal variability of atmospheric circulation in the Arctic region. The classifi cation of atmospheric circulation forms according to Wangenheim — Girs for cold (November – April) and warm (March – October) periods of the year are used. We consider the repeatability of series with one form of circulation for gradations of duration and variability in time of this characteristic, as a parameter of stability of synoptic processes in the region under consideration. As additional characteristics, the horizontal gradients of the pressure field are calculated according to the atmospheric pressure at sea level. Estimates of the variability of the meridional and latitudinal directions of air advection are obtained.

The results of the atmospheric sea surface layer aerosol composition studies executed during expedition “Sever-2015” on the route from Arkhangelsk to the Severnaya Zemlya archipelago from October 9 to 26, 2015 are presented. The data about mass concentration of black carbon (EBC) obtained with high spatial-temporal resolution in the White, Barents and Kara Seas showed its signifi cant variability: from background values about 20 ng/m3 to values of more than 1000 ng/m3 during periods of air mass transfer from the continent. Cluster analysis of the microstructure of natural arctic aerosols gave possibility to identify the dominant groups of particles of sea salt and calcium sulfate. In case the increase of EBC up to 250 ng/m3 the groups of carbon-containing aerosols and particles rich in sulfur, characteristic for emissions from the combustion of natural fuel were revealed.

Vertical profiles of ice temperature were measured in November 2010 – September 2011 at “North Pole-38” drifting station. These observations were made at five locations, including young ice, residual first-year ice, second-year ice, multi-year ice. Methods of measurements are considered. Time-temperature profiles for all types of ice as well as time profile for the gradient of temperature of ice, as an example, are shown. A snow cover gives substantial thermal resistance, reducing a heat flux between atmosphere and ocean. The periods of warming-up and cooling of ice in the annual cycle alternate with periods, when vertical distribution of ice temperature close to linear: with a maximal gradient in winter and zero gradient in summer. A general pattern of the seasonal evolution of ice temperature is discussed. A cold front is propagating down through the ice from October to June. Ice growth lasts, on the average, to a middle of May. Warming of ice to the freezing point occurs mainly in August.

The results of long-term studies of organic compounds in separated water bodies in two regions: Lake Stepped, Prydz Bay, Commonwealth Sea, (Antarctica) and lakes of the periphery of the Kandalaksha Gulf of the White Sea (the Arctic) are presented. It is established that the eutrophication of these reservoirs largely depends on the connection of these lakes with the sea. Coastal anthropogenic activity affects to a lesser extent. The restoration of the ecosystem of these lakes occurs at the launch of sea waters. The greatest differences between organic compounds in the Arctic and Antarctic waters are established in hydrocarbons. In Antarctica, due to the lack of vegetation, alkanes are dominated by autochthonous compounds, and in the Arctic along with autochthonous, allochthonous.

The results of engineering surveys in the area of the Mirny and Progress stations and fi eld base Molodyozhnaya are discussed in the paper. During the austral summer fi eld season of the 62nd RAE (2016/17) wide complex of the scientifi c and applied research has been carried out. It included the engineering, aerial photography, glaciological, drilling, geodetic and GPR investigations to ensure the safety of transport operations in the area of Russian stations Mirny and Progress (East Antarctica). The scientifi c tests to study sea ice have been carried out on the frozen water area of Nella Fjord, near Progress Station.

The estimates of the tides harmonic constants are given over the period from 1962 to 1993. They were received using a least square method according to AARI. Quality estimation of the sea level observations was performed. The annual series with bad observations were transformed by means of tides calibration. The Estimation of the tides fi ne structure – harmonics of the second and third degree of the potential according to analysis over the period from 1962–1985 was received. The statistical estimations of the sea level in the separate typical years were calculated using initial and corrected series.