The article briefly substantiates the need for regular monitoring of the state of the waters of the Russian Arctic Seas and the Arctic Basin of the Arctic Ocean. The goals and objectives of monitoring hydrological conditions are formulated. General ideas about the development and construction of a system for monitoring hydrological conditions in the Arctic are expressed, taking into account the use of modern instruments and methods of oceanographic observations. It is shown that the most promising is the use of autonomous measuring complexes in the monitoring system, including moorings and drifting profiler buoys. The special value of satellite oceanographic data is emphasized. No less important are coastal observations carried out over the network of Roshydromet stations, as well as at research centers united into the Arctic Space-Distributed Observatory. The inclusion into this Observatory of the ice self-propelled platform “North Pole”, which will replace the drifting stations, will allow not only observing and measuring the main characteristics of the water masses, but also conducting controlled field experiments that will provide a deeper understanding of different-scale physical processes occurring in the waters of the Arctic Ocean. An important element of the monitoring system is data assimilation based on the use of numerical models that allow for the effect of the ice cover in the atmosphere-sea ice-ocean interaction system.

One of the main directions of theoretical and applied research in the Arctic is the study of physical and mechanical processes in the atmosphere — ice — ocean system. For this purpose, theoretical and experimental problems are solved. The paper employs the method of monitoring the state of drifting ice by means of autonomous seismic stations in the MOSAiC international expedition in 2019–2020. The method of remote registration of ice information with a discreteness of 100 Hz made it possible to obtain data on the processes of compression and crushing of ice of various temporal and spatial scales. The paper presents early findings on the development of physico-mechanical processes in the ice cover under the influence of wind, oceanic gravitational waves, compression and crushing phenomena during large-scale deformations in drifting ice. The amplitude-frequency spectra of surface gravitational waves obtained in this work provide sufficient reason for attributing the phenomena described to swell waves and infra-gravity waves that occur in the stormy areas of the oceans. New data have been obtained on low-frequency horizontally polarized waves caused by the compression of ice and movements along breaks in the cohesive ice cover. The article considers the possibilities of using instrumental monitoring of the occurrence and development of tidal compression and crushing in the drifting ice of the Arctic Ocean. The results obtained can be used to develop methods for predicting the state of ice in real time both in engineering tasks and for improving weather and climate forecasting models.

The Obskay guba Bay is a region of rapidly developing oil and gas exploration. Knowing the current sea ice conditions including dangerous phenomena e. g. ridges and stamukhas is important for the safety of coastal and underwater construction as well as for ecological risk assessment. With this study, we aim to obtain new data on sea ice seasonal cycle in the southern and central part of the Obskay guba Bay for 10 years (from 2007 to 2017) and to demonstrate the capacity of satellite data in obtaining varying sea ice characteristics in the region. Analyzing daily visual MODIS and available Sentinel-1 SAR imagery, we derived dates of sea ice and fast ice formation, fast ice breakup and melt onset and the onset of ice-free period. For this purpose the satellite data were analyzed manually by sea ice expert. In addition, of sea ice ridges were derived and the sea ice drift data wea automatically processed in order to locate motionless sea ice features — stamukhas. The distribution of sea ice floes and field size in the region was derived from MODIS data. The analysis showed that there is a tendency towards a shorter ice covered period based on the data from 2007 to 2017. Overall, the formation of sea ice starts 9 days later and fast ice breakup occurs 16 days earlier compared to the long-term mean (1947–2010). The majority of ridges were located in the central part of the region and directed along the coast. The analysis confirmed absence of large stamuhas visible to be applied method (with a horizontal size of 100 m). The predominant sea ice field size range lies 500–1500 m. The study shows that a combination of images obtained in the optical range of the survey with radar data makes it possible to supplement the classical visual assessments with the results of automatic methods for detecting fast ice, detecting stamukha, as well as ice drift and deformation.

The reduction of the sea ice area in the Arctic is one of the most notable consequences of climate change, with the Kara Sea contributing about 5 % to the overall reduction. The aim of this study is to assess the impact of changes in climatic conditions on the reduction of the area and thickness of the sea ice in the Kara Sea and the possibility of using the established dependencies for climate forecasting. The article provides quantitative estimates of the relationship between interannual changes in the sea ice thickness and sea ice extent in the Kara Sea and climate changes in the region and the remote influence of the sea surface temperature in the tropical North Atlantic for 1979–2019. The paper uses observation data obtained at meteorological stations, ERA5 reanalysis and data on the sea ice extent from the Arctic and Antarctic Research Institute website. In summer, the melting of sea ice is largely due to changes in the surface air temperature (correlation coefficient from –0.57 to –0.91). In winter, the ice thickness depends on the sum of frost degree-days (r = –0.80). The temperature regime, in turn, is determined by the radiation balance, namely, by the variability in the long-wave flow due to the increase in the water vapor content. On the basis of the relationships established, a linear regression model is proposed for forecasting the sea ice area with a lead time of about three months. The model is effective and statistically significant. The paper considers the remote influence of the sea surface temperature anomalies in the North Atlantic tropics on the ice coverage of the Kara Sea. The response of the sea ice extent to the sea surface temperature in the low latitudes is 30–34 months late. The significant correlation between the anomalies can serve as a basis for predicting the sea ice area in the Kara Sea with a lead time of up to three years.

The collections belonging to the Museum-Archive of the history of study and development of the European North of the Barents Center of the Humanities — Branch of the Federal Research Center «Kola Science Centre of the Russian Academy of Sciences» (BCH KSC RAS), contain several handwritten diaries by members of Arctic expeditions organized in the first half of the XXth century. The article discusses the value of the expedition diary of a member of a Russian Arctic expedition to Dikson Island (1916), the hydrometeorologist Innokenty Tikhomirov (1890–1955), as a possible source of data on the history of organizing and conducting scientific research in the Arctic. Based on the data presented in the diary, the paper reconstructs the progress of work on the organization of the northernmost meteorological station on Dikson Island in 1916.