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The ice situation around a hydraulic structure is the input data for the assessment of the ice loads and impacts on the structure. The design load on a bank-protection structure is determined from the level-ice thickness of given exceedance probability found by statistically processing field observations over the period of maximum ice loads, depending on the class of the structure. The thickness values of exceedance probability p = 1% were calculated. The long-term variability of ice thickness at the mouth of the Oka River was assessed to develop an upgrade project for the right-bank protection structures in Nizhny Novgorod to allow for the changing climate and the human impact on the riverbed. [ABSTRACT FROM AUTHOR]

In recent decades, the Inner Mongolia Reach of the Yellow River (IMRYR) in China has experienced new characteristics in terms of ice conditions due to human activities and climate change. It is crucial to develop a comprehensive river ice model for this reach that reflects the changing physical characteristics of ice events. However, simulating river ice process in the IMRYR using numerical model is challenging due to the scarcity of observed data on river geometry, hydrology, meteorology, and river ice conditions. With latest field measurements, this study examined the spatiotemporal variations of ice conditions in the IMRYR. In the development of river ice model, this study tackled various challenges such as incomplete river geometry, insufficient tributary flow information, and the identification of ice bridge locations. By improving the one-dimensional river ice model, the study simulated the ice development process during the 2012–2013 ice flood season in the IMRYR. A comparative analysis was conducted between the simulated and observed water temperature, ice cover thickness, ice front locations, and flows, showing a good agreement. This study analyzed and determined the ice hydrodynamics, thermodynamics, and relevant river parameters, providing a deeper understanding of the intricate interactions and dynamics associated with the formation and behavior of river ice in the Yellow River. This research can provide scientific basis and methodological support for ice disaster prevention and control in the Yellow River, as well as insights and technical means for simulating comprehensive river ice processes in natural rivers and artificial channels. The Yellow River is one of the rivers in China that experiences frequent ice-related disasters, with the main occurrences happening in the Inner Mongolia Reach (IMR). In recent decades, the IMR has faced new challenges in ice evolution, including changing climatic conditions, severe channel siltation, and expanded ice-related channel storage, making the understanding of ice conditions more complex. The China Institute of Water Resources and Hydropower Research, commissioned by the Hydrographic Bureau of the Yellow River Conservancy Commission, conducted numerical simulations of the ice processes in the IMR. Based on the new characteristics of ice conditions in the Yellow River, a mathematical model was proposed to simulate the development of winter ice conditions in data-scarce regions. The one-dimensional river ice process model was enhanced to enable dynamic simulations of the ice processes in the IMR, and accurately capturing the evolution of winter water temperature, ice cover thickness, ice front progression, flow rate, and water level. This study provides valuable scientific basis for ice forecasting, ice control operations, and disaster prevention in the Yellow River. The improved model has been adopted by the Hydrographic Bureau of the Yellow River Conservancy Commission, and additional categories and sampling frequencies of hydrological and meteorological data have been tailored for the Inner Mongolia Reach considering specific data requirements for the model. [ABSTRACT FROM AUTHOR]

The paper represents an attempt to understand the impacts produced by the North Atlantic Oscillation on the ice cover regime of the largest coastal lake in Poland situated in the northern part of the country. The purpose of the study was to estimate the impact of the North Atlantic Oscillation on selected ice cover parameters. The study also attempts to examine other factors that may affect its significant impact on observed changes in the climate. Water temperature data are used to assess temperature conditions in aqueous ecosystems as well as determine the heat absorption capacity of these systems. This allows one to then determine cooling rates in the event of ice cover formation. The data analysis provided in the paper focuses on selected characteristics of ice cover conditions (i.e. dependent variables) including the number of days with ice and maximum ice thickness in relation to NAO index changes (i.e. independent variables) for the reference period 1960/61–2009/10. In addition, the paper divides the studied period into 10-year subperiods in order to capture the weakest and strongest phases of NAO and assess the extent to which they affect the duration of ice cover. A large increase in the mean air temperature (1.8°C) occurred in the years 1960–2010. Trendline analysis indicates that the number of days with ice cover declined by about 60 days and the maximum thickness of ice cover decreased by about 10 cm. Oceanographic research employs satellite image data in order to accurately assess human impact. Therefore, ice cover forecasts generated for consecutive winter seasons may become an important tool in this type of assessment.

Ice classed ships have specially designed, reinforced hulls and large engines, which may influence open-water fuel efficiency. Ice classification typically requires minimum engine power limit, possibly leading to an over-sized engine for open water operation. Most of the existing studies of energy efficiency of ice classed ships assume that these vessels consume more fuel also in open water conditions than conventional ships. In this work we analysed the EU Monitoring, Reporting and Verification database to understand the differences of main engine size, light ship mass, payload capacity and real-life reported and verified annual mean fuel consumption between ice classed ships and those without ice class using statistical methods. Ice classed ships were found to have on average 11% more hull mass, 13% more main engine power and 13% less deadweight capacity than ships without ice class, but some vessel types had inversed results. Also, ice class does not predict increased fuel consumption for all vessel types. In addition, according to the Automatic Identification System data, about 47% of vessels with reported ice class did not sail in ice covered areas during 2018–2022. These findings should open the discussion for more precise relief mechanisms of emission trading systems granted for ice classed vessels. • Only around half of the ice-classed vessels that reported to MRV sailed in ice during 2018–2022. • Ice-classed ships have more light ship mass, larger main engines and less cargo capacity than non-ice-classed vessels. • Ice classification does not predict increased fuel consumption for all vessel types. [ABSTRACT FROM AUTHOR]

A characteristic feature of the eastern Kara Sea, which is separated from its central part by the shallow Central Kara Rise, is a later ice breakup, a shorter ice-free period, and lower water temperature. Zooplankton in this part of the sea is virtually unstudied. The first data on the composition, spatial distribution of zooplankton, age structure and feeding of the dominant species, and their grazing impact on phytoplankton were obtained in the cruise 125 of the R/V Professor Shtokman (September 2013) and cruise 63 of the R/V Akademik Mstislav Keldysh (September 2015) to the eastern Kara Sea. 2015 was a typical year in terms of the ice regime for this region, while in 2013, seasonal ice coverage lasted longer than usual. Zooplankton biomass (17–112 mg dry weight m–3), to which copepods Calanus glacialis contributed the main portion, were close to the values in the central Kara Sea in September. The seasonal development of the C. glacialis population began much later than in the central Kara Sea, but development of Metridia longa was not influenced by the specifics of the ice regime and hydrophysical conditions in the eastern Kara Sea. The interannual differences in the timing of ice retreat had almost no effect on the zooplankton abundance, seasonal development of the dominant copepod populations, feeding activity, and grazing impact on phytoplankton. [ABSTRACT FROM AUTHOR]

A characteristic feature of the eastern Kara Sea, which is separated from its central part by the shallow Central Kara Rise, is a later ice breakup, a shorter ice-free period, and lower water temperature. Zooplankton in this part of the sea is virtually unstudied. The first data on the composition, spatial distribution of zooplankton, age structure and feeding of the dominant species, and their grazing impact on phytoplankton were obtained in the cruise 125 of the R/V Professor Shtokman (September 2013) and cruise 63 of the R/V Akademik Mstislav Keldysh (September 2015) to the eastern Kara Sea. 2015 was a typical year in terms of the ice regime for this region, while in 2013, seasonal ice coverage lasted longer than usual. Zooplankton biomass (17–112 mg dry weight m–3), to which copepods Calanus glacialis contributed the main portion, were close to the values in the central Kara Sea in September. The seasonal development of the C. glacialis population began much later than in the central Kara Sea, but development of Metridia longa was not influenced by the specifics of the ice regime and hydrophysical conditions in the eastern Kara Sea. The interannual differences in the timing of ice retreat had almost no effect on the zooplankton abundance, seasonal development of the dominant copepod populations, feeding activity, and grazing impact on phytoplankton. [ABSTRACT FROM AUTHOR]

This article describes a probabilistic model (stochastic generator) of spatiotemporal variability of sea ice concentration. The values of the concentration are generated at the nodes of the spatial grid with 10‑km resolution; the model time step is 1 day. The change in ice concentration with time (temporal variability) is modeled on the basis of a matrix of transient probabilities (discrete Markov chain), each row of which is a distribution function of the conditional probability of changes in the concentration. Spatial variability is determined by empirical probability fields, with which the observed changes in fields of concentration are associated with known conditional probability distribution functions. To identify the parameters of the stochastic generator, satellite data from the OSI SAF project for 1987–2019 were used. The generator takes into account seasonal, interannual, and climatic variability. Interannual and climatic variability are determined on the basis of a stochastic model of changes in the types of ice coverage. In order to verify the developed stochastic generator, we compare the statistical indicators of observed and calculated ice fields. The results show that the field-average absolute error of statistical characteristics of the ice concentration (average and standard deviation) does not exceed 3.3%. The discrepancy between the correlation intervals of ice coverage calculated from the model and measured ice concentration fields does not exceed 2 days. The variograms of the modeled and observed fields have a similar form and close values. As an example, we determine the duration of navigation of Arc4 ice class ships between the Barents and Kara seas using synthetic fields of the concentration reproduced by the stochastic generator. [ABSTRACT FROM AUTHOR]

Article describes a probabilistic model (stochastic generator) of spatial-temporal variability of sea ice concentration. Values of the ice concentration are generated at the nodes of the spatial grid with 10 km resolution; the model time step is one day. The change in ice concentration with time (temporal variability) is modeled on the basis of a matrix of transient probabilities (discrete Markov chain), each row of which is a distribution function of the conditional probability of changes in the ice concentration. Spatial variability is determined by empirical probability fields, with which the observed changes in fields of the ice concentration are associated with known conditional probability distribution functions. To identify the parameters of the stochastic generator, satellite data from the OSI SAF project for the period 1987–2019 were used. The generator takes into account seasonal, interannual and climatic variability. Interannual and climatic variability are determined on the basis of a stochastic model of changes in the types of ice coverage. In order to verify the developed stochastic generator, we compared the statistical indicators of observed and calculated ice fields. The results showed that the fieldaverage absolute error of statistical characteristics of the ice concentration (mean and standard deviation) does not exceed 3.3%. The discrepancy between the correlation intervals of ice coverage calculated from the model and measured ice concentration fields does not exceed 2 days. The variograms of the modeled and observed fields have a similar form and close values. As an example, we determined the duration of navigation of Arc4 ice class ships between the Barents and Kara Seas using synthetic fields of the ice concentration reproduced by the stochastic generator.

Different environmental conditions such as pollution, rain, and frost affect the performance of polymeric insulators. In cold climates, insulators may become frozen, resulting in non-uniform distribution of potential and electric field around the insulator. Non-uniform distribution of potential and electric field along the insulator in turn cause problems such as erosion and flashover. Also, due to the wind direction in cold regions, the pollution layer accumulates non-uniformity on the insulator surface. This paper investigated the effect of ice layer with different configurations in combination with ring-shaped contamination, which is more common in cold regions, on the insulator surface to obtain the electric field distribution and leakage current of a 20 kV polymeric insulator. For this purpose, software based on finite element method (FEM) was used. Experimental test for evaluating the leakage current analysis of ring-shaped polluted insulator under ice condition was done in a laboratory clean fog chamber. The results of experimental data and the proposed simulated models were compared and validated. The results revealed that parameters such as increasing the freezing layer and its intensity, continuity of the freezing structure and electrical conductivity of the ice layer would enhance the amplitude of the electric field and leakage current, increasing the probability of flashover. Also, in the combination of ring-shaped contamination layer and freezing, the parameters of the ice layer are more influential than the contamination layer on the electrical behavior of the insulator. [ABSTRACT FROM AUTHOR]

Ship speed forecasting in harsh and uncertain ice conditions is a core technology enabling Arctic fleet planning at strategical, tactical, and operational levels of maritime logistics. In this benchmark study, we examine five alternative models that differ by their nature (process-oriented, data-driven, and hybrid approaches) and set of predictors (combinations of AIS and ice parameters). To develop these models, AIS data on YamalMax LNG carriers and ice data from diagnostic charts were merged in a joint dataset covering the period 2017–2022. A detailed description of this dataset is given in the article, including spatiotemporal variability of ice parameters and ship speed. Actual and predicted speeds are compared by five statistical indicators not only in the case of speed estimation at a point, but also when calculating average speed over long-distance route segments. The article analyses the difference in accuracy of speed predictions in various geographical areas of the Arctic and during different seasons. The degree of influence of model parameters is estimated using a SHAP approach. Several conclusions about the architecture of forecasting models and their predictors are drawn as a result. • Machine Learning, process-based, and hybrid models to predict ship speed are compared • Consideration of both ice and AIS data provides greater accuracy in speed prediction • Process-oriented model is more sensitive to ice parameters than the machine learning • Difference in accuracy between linear and nonlinear ML models is not so significant • Pointwise speed prediction is rough, but accuracy increases by 40% over long segments [ABSTRACT FROM AUTHOR]

The series of data on the fast ice thickness and the surface air temperature at the Roshydromet land-based polar stations in the Laptev Sea are analyzed. Observations for the last 15-year period (2005-2020) are compared to observations prior to 2004, and the changes corresponding to the new climatic conditions are revealed. Over the past 15 years ice thicknesses during the period of maximum ice growth (maximum ice thickness) have decreased by 6% on average. The ice growth process has become much slower, transition between the sequentional stages of ice development is observed 1-2 ten-days periods later. The surface air temperature at the considered stations was on average 3°C higher than for the previous period. The most significant changes are observed in the autumn months (October, November) and in April. The cumulative sum of the degree-day of frost averaged for the Laptev Sea stations, decreased by 15%; all 15 recent winter seasons can be classified as mild. It was revealed that the decrease of the cumulative sum of degree-day of frost is in a good agreement with the decrease of the mean-seasonal ice thickness (averaged for November-May) at the stations. This indicator seems to be more informative than the maximum ice thickness for estimation of the changes. Averaging over all stations revealed a 10% decrease of the mean-seasonal ice thickness during the past 15 years.

Shallow, lagoonal coastal lakes of the Southern Baltic are exceptionally susceptible to atmospheric factors. This work examines the influence of winter air temperatures in Ustka on ice parameters (dates of first ice occurrence and last ice disappearance, ice season duration, number of days with ice, and maximum ice thickness) on Southern Baltic coastal lakes (Jamno, Bukowo, Gardno, Łebsko), and trends displayed by changes in these parameters over the period spanning 1960/61-2019/20. The research data was retrieved from the archives of Institute of Meteorology and Water Management – National Research Institute. As a first step of the analysis, we investigated the statistical relationships in spatial and temporal variations in winter air temperature and coastal lake ice parameters. Correlation and regression method was employed to determine the influence of air temperature on coastal lake ice conditions. Correlation and determination coefficients were calculated, and linear regression equations were determined. The statistical significance of the observed relationships was assessed using Fisher-Snedecor test. Additionally, linear trend models were constructed. Our analysis indicates that from 1960/61 to 2019/20, the average rate of increase in winter temperature (December-March) in Ustka equalled 0.04°C ⋅year-1. The correlation coefficients for air temperature versus ice parameters were highly statistically significant (p

Shallow, lagoonal coastal lakes of the Southern Baltic are exceptionally susceptible to atmospheric factors. This work examines the influence of winter air temperatures on ice parameters (dates of first ice occurrence and last ice disappearance, ice season duration, number of days with ice, and annual maximum ice thickness) on Southern Baltic coastal lakes (Jamno, Bukowo, Gardno, .ebsko), and trends displayed by changes in these parameters over the period spanning 1960/61-2019/20. The research data was retrieved from the archives of Institute of Meteorology and Water Management. National Research Institute. As a first step of the analysis, we investigated the statistical relationships in spatial and temporal variations in winter air temperature and coastal lake ice parameters. Correlation and regression method was employed to determine the influence of air temperature on coastal lake ice conditions. Correlation coefficients were calculated, and linear regression equations were determined. The statistical significance of the observed relationships was assessed using Fisher-Snedecor test. Additionally, linear trend models were constructed. Our analysis indicates that from 1960/61 to 2019/20, the average rate of increase in winter temperature (December-March) equalled 0.04‹C-year.1. The correlation coefficients for air temperature versus ice parameters were highly statistically significant (ƒ¿<0.001). The strongest relationships (with correlation coefficients below -0.90) occurred between air temperature and number of days with ice. Ice season duration and number of days with ice are both closely linked with last ice disappearance date and ice thickness. Our analysis shows that a 1‹C increase in average seasonal air temperature will result in the number of days with ice on the studied coastal lakes becoming reduced by 16-17 days. All trends in ice parameters indicate a mildening of ice conditions. The assessed trends are statistically significant, except for L (date of last ice disappearance) for Lake Jamno and H (annual maximum ice thickness) on lakes Jamno and Bukowo, at least at ƒ¿=0.05 level. Their correlation coefficients are usually in the range from -0.35 to -0.50. The strongest trends were observed for ice season duration. Ice season duration shortens in an eastward direction by 0.66 dayEyear.1 (Lake Jamno) to 1.16 dayEyear.1 (Lake .ebsko). All correlation coefficients for ice trends were found to increase eastward, which could be explained by an increasing influence of the warming climate over the Southern Baltic in this direction. The strong relationships between air temperature and Southern Baltic coastal lake ice parameters, and the determined rate of changes may have a significance for forecasting, as the shifting dates of ice formation and disappearance on lakes are highly important for the lake hydrodynamics, and the functioning of aquatic ecosystems. [ABSTRACT FROM AUTHOR]

The expediency of transportation on the TRANS-Siberian railway is not in doubt for any of our contemporaries now, and its importance for development of Siberia and the Far East is quite obvious. However, this attitude to this transport artery was not formed immediately. Let us recall at least the fact that the Tomsk merchant class insisted that the road passed through Aleksandrovsk (now Novosibirsk). The decision of Tsar Alexander III on construction of the railway played crucial role. The built road contributed to the development of the cities through which it was laid. The situation with the decision on organization of the free movement from the mainland to Sakhalin seems to us similar to the one that was in front of laying of the line across Siberia. The issue will have to be addressed sooner or later. The laying of the highway to the island will give a powerful impetus to the social and economic development of the territories adjacent to the road and railway, which will pass through the bridge. In this article, we research specifics of climatic and hydrological factors that determine choice of type of hydraulic structures in the Nevelskogo Strait. The relevance of the research is dictated by the need for comprehensive review of the conditions that determine the choice of the Tatar Strait crossing line by the bridge. After taking into account the influence of geological and geomorphological factors, we turn our attention to climatic, weather and hydrological processes that will have a permanent impact on construction and operation. The aim of the research is to link together and analyze the data that characterize features of atmospheric and hydrosphere processes in narrow part of the Tatar Strait and conduct scientific research that will complement for engineering research and help identify based on simulation safest opening for construction of hydro-technical utilities that will connect opposite banks. Materials and methods. The materials for the study were cartographic materials, data of remote sensing of the Earth, information on climatic and weather conditions, data of hydrological, meteorological, Oceanographic observations, information obtained as a result of research works and engineering surveys in which the authors participated, as well as information from literary sources. Mapping in the geographic information environment allowed creating thematic maps reflecting the dynamics of hydrometeorological processes. The obtained information was used in construction of models of water circulation, formation and degradation of ice cover in the Nevelskoy Strait with the use of geoinformation technologies. The authors took a direct part in research of the leading line «Novy» in 2001. As result of the research of the features of hydrometeorological conditions within the water area of the Nevelskogo Strait and its coasts, based on satellite monitoring data, observations at nearby weather stations, as well as confirmed by information obtained during engineering surveys, it was found that in area of the Nevelskoy Strait, adverse natural phenomena should be taken into account when choosing technical design solutions for selecting type of bridge or tunnel construction from mainland to Sakhalin. The spatial and temporal distribution of radiance in the area is due to astronomical reasons, decrease in duration of the sunshine in De-Kastri and Pogibi compared to Nikolaevsk-on-Amur is associated with frequent fogs that occur during atmospheric processes on border of land and sea. Extreme values of air temperature in Pogibi were registered at the Pogibi weather station – maximum of 27,3 °C and a minimum of –44,0 °C. Index of continentality is very high (amplitude – 71,3 °C), which can be explained by the influence of air masses removal from mainland in winter period. The important indicator for projecting – duration of frost-free period-ranges in Pogibi from 88 to 186 days (average – 137). Daily precipitation totals during warm period reached maximum values of 88 mm in October, 81 mm in August, and 78 mm in July. Snow cover in Pogibi lasts from 153 to 216 days. Winds of ≥30 m/s occur annually in spring and autumn, sometimes exceeding 40 m/s. Fogs in described area are observed throughout year. Snowstorms in strait and on its coastal are very common. Any increase in wind in winter is accompanied by blizzard transfer of snow. Thunderstorms occur 4–5 times a year. Dust storms are rare. Horizontal water circulation in the Northern part of strait is anticyclical in winter, and cyclonic circulation is active from May to September. In general, in spring water movement speed on surface is 2–7 cm/s and in summer it decreases to 1–4 cm/s. Changes in sea level in the Tatar Strait are in the range of 3,2–4,0 m. Duration of ice period at time moderate types of winters is 201 days. Collar ice in Pogibi in late March – early April averages 160 cm and varies from 119 to 190 cm depending on type of winter. Due to the strong tidal currents, the solid ice cover in channel of the middle part of strait is formed very rarely and on short time. The result of the increased ice cover dynamics is multiple layers of young ice up to 30 cm thick. Coastals in southern part of Strait are resistant to abrasion processes and practically do not collapse. The area enclosed between liding lines Lazarev cape – cape Pogibi in the North and cape South – cape Tyk – in the South has the most favorable conditions for the construction of bridge. Climatic and hydrological conditions throughout have relative similarity, which allowed us distinguish it when zoning as independent unit. The performed research allows us give an advantage to leading line «Novy» (cape Nevelskogo – cape Lakh).

Variability of the ice conditions in the Chukchi Sea is considered in various scales on the basis of all available information for 1950–2017. Its dependence on the atmospheric circulation patterns measured with the Arctic Oscillation index is shown. Tendency to the ice reducing has intensified in the early 21st century in the Chukchi Sea that is accompanied with changes in its seasonal development, as shift of the ice destruction beginning from June to July, gradual increasing of the ice destruction rate till September, shift of the ice formation beginning from September to October, and delay of the ice spreading over entire sea area from November to December. Relationship of the ice conditions in the Chukchi Sea on summer phase of Arctic oscillation is detected: the maximum positive values of the index always correspond with heavy ice conditions, the minimum values of the index correspond with low-ice conditions only, and various ice conditions are observed in other years without neither positive nor negative extremities of Arctic oscillation. However, winter phase of Arctic oscillation does not affect on the ice conditions in the Chukchi Sea in June-November.

• Ice thickness, ice conditions, and ice class directly affect shipping costs. • Ice conditions are softening, decreasing the expected NSR fee level. • Ships of some ice-classes can sail within the NSR independently. • Ships without ice protection are unprofitable for shipping in the NSR. • The NSR icebreaker escort fee may be several times lower than the SCR toll. Even though the Arctic ice is melting and Polar routes are being extensively studied, the amount of cargo shipped through the Northern Sea Route (NSR) remains low. Employing current data on the NSR operation provided by China Ocean Shipping Company, this paper investigates annual profitability of the NSR-SCR combined use, when a vessel sails through the NSR in summer and the SCR in winter. A Handysize general cargo ship is used as a model vessel since it allows reaching nearly maximum load rate and can sail through shallow areas of the NSR. This article proposes including ice thickness and ice conditions in the traditional cost comparison. The first parameter directly affects sailing speed, and hence other cost variables, while the second one is included in the official NSR navigation rules and connected with icebreaker escort fee. This paper also contributes to the existing literature by considering total shipping cost as a function of a vessel's ice class with corresponding building premiums and fuel consumption increments. The proposed approach is easily replicable, so shipping companies might use it to rethink their positions on shipping through the NSR. The overall conservative comparison reveals that the NSR-SCR combined shipping scheme can only be more competitive than sailing through the SCR if a shipping company provides a sufficient load rate on the NSR leg and uses a ship of a reliable ice class to navigate throughout the summer navigation. The NSR-SCR combined shipping scheme becomes attractive if the NSR leg is short, and the crude oil price is high. [ABSTRACT FROM AUTHOR]

The paper considers the current status of Russian Icebreaker fleet. The potential application of sum of degree-days of frost to characterize easy, moderate and difficult ice conditions in the Russian seas is proved. The restrictions for different ice-class vessels to navigate in easy, moderate and difficult ice conditions are analyzed. It is shown that the power of the modern icebreaker fleet enables to navigate successfully in the Russian seas in conditions of mild and moderate winters, as well as in conditions of severe and extremely severe winters. The analysis of construction and operation of the modern icebreaker fleet in 21st century leads to the conclusion that the real challenge of winter navigation in the non-Arctic seas is not due to ice thickness but due to the increasing number and size of vessels requiring icebreaker assistance.

The article examines the problems and development prospects for the international transit of goods along the NSR. The existing restrictions on increasing freight traffic up to 80 million tons per year declared in program documents are identified. An option for its enhancement based on the domestic fleet of Arctic cargo ships is proposed. The article summarizes the main shortcomings of earlier studies assessing the transit capabilities of the NSR. A model for assessing the optimal number of ships for the transportation of goods is proposed taking into account climatic, physical-geographical, technological, and temporal constraints and risks. Within the framework of the model, the cost of goods transportation was estimated for implementing two scenarios of transit traffic. [ABSTRACT FROM AUTHOR]

The ice regime of the Sea of Azov over the period of 20th and 21nd centuries was investigated using the author's GIS «The ice regime of the Southern Seas of the Russia». The long-term dynamics of the ice cover, duration of the ice stay as well as beginning and end of the ice period were considered. It has been found that for the period of 1950–2015 the average annual value of the Azov Sea ice cover area is 33%, while the average area of the fast ice is 6.3% of the total area of the sea. Value of duration of the ice cover stay on the sea surface has been refined, and this value is 115 days near the hydro-meteorological station (HMS) Taganrog and 63 days near the HMS Kerch. The typification of winters according to the degree of severity was performed on the basis of data from three coastal meteorological stations: Taganrog, Genichesk, and Kerch. Winters of moderate type were shown to be prevailing during the entire analyzed period. Totally, 15 severe, 70 moderate and 40 mild winters were isolated for the period 1883-2015, while for 1950–2015 the statistics was the following: 9 severe, 43 moderate, and 14 mild winters in Taganrog, and 10 severe, 40 moderate, and 16 mild winters in Kerch.

The goal of the study was to examine ice cover conditions that accompanied the passage of convoy of seven Polish vessels from Europe to the Far East in year 1956, which initiated an international commercial shipping transit. Several different sources of information on the state of ice cover in the Arctic were used in this study. Ice conditions (decisive for ability of a merchant vessel or icebreaker to cross the route) during the following navigational seasons in most of the NSR areas showed extremely divergent results - from the most favorable to the most difficult and vice versa. Existing in years 1940-1957 ice cover conditions and shipbuilding technologies did not guarantee a successful transit passage in one navigation season. The Soviet Union used icebreakers that were not able to lead vessels in heavy ice conditions that occurred in 1950s. The NSR Administration used passive strategy ? waiting for improvement of ice conditions - instead of forcing heavy ice. Passive strategy of navigation through the NSR included wintering and continuation of passage next year when ice conditions improved. Annual variability of ice conditions approximated by third degree polynomial line showed trends well. However, the high annual anomalies of ice conditions in relation to trend line did not allow for effective forecasts on particular sections of the NSR in next navigation season.

The possibility of using the Marine Hindcast and Forecast System (MHFS) developed at Zubov State Oceanographic Institute for short-term forecasting of hydrometeorological and ice characteristics of the Caspian Sea is demonstrated. The presented implementation of the system is based on the regional nonhydrostatic atmospheric model WRF (Weather Research and Forecast Model) and model of marine circulation INMOM (Institute of Numerical Mathematics Ocean Model). The system performance is assessed for the period from January 1 to March 31, 2017 by comparing the forecasts of hydrometeorological characteristics with observational data from hydrometeorological stations. The quality of reproducing sea ice characteristics based on ESIMO objective data is also evaluated. [ABSTRACT FROM AUTHOR]

Abstract—The large-scale expedition of cruise 76 of the R/V Akademik Mstislav Keldysh was performed by the Shirshov Institute of Oceanology from July 1 to August 6 2019 within the Program "Marine Ecosystems of the Siberian Arctic." Seventy-one scientist from Russian Academy of Sciences institutes, Moscow State University, and VNIRO participated. Coordinated hydrophysical, hydrochemical, biooceanological, geochemical, and radioecological research was carried out over the shelf and continental slope in the Kara Sea, Ob estuary, and in the eastern coastal bays of Novaya Zemlya. [ABSTRACT FROM AUTHOR]

This paper analyzes the past and current situation of geological exploration drilling on the Arctic region continental shelf. Along with climate conditions, the strategy of drilling is greatly infl uenced by technical accessibility of licensed sites, the latter depending on achieved level of equipment and technologies. Since 2014 the USA, the European Union countries and a number of other states have imposed sanctions against Russia. Sectoral sanctions, prohibiting access to technologies employed in the Arctic region shelf projects, have become an important part of these sanctions. This research is aimed at assessing the infl uence of sectoral anti-Russian sanctions on geological exploration drilling in the Arctic seas. The choice of geological exploration drilling is not accidental as the majority of Russian Arctic projects are at this particular stage now.Over the recent forty years, the country has accumulated considerable practical experience of conducting geological exploration drilling and the Arctic region field development. Our analysis demonstrates that modern Russia has necessary technologies for exploration and field development in the Arctic region. In fact, Russia is the only country, which actually continues its operations in the Arctic region amid a sharp decline of oil prices. Imposing sectoral sanctions related to equipment and technologies of developing the Russian Arctic shelf is inefficient.It is forecasted that in the coming decade, the continuing global warming process will make the majority of regions of the Barents Sea and the Kara Sea – where a number of large and gigantic fields have already been discovered – more accessible for conducting geological exploration drilling. It is possible to use here the traditional types of off shore drilling units with a low ice rate. This will totally eliminate any technical and technological problems of drilling. The USA are expected to enter the market of arctic hydrocarbons from new fields by the middle of the 30s of the 21 century. One can forecast a substantial output from exploiting Russian fields to be achieved by the same time. Hence, imposed sanctions are mainly aimed at delaying the implementation of Russian Arctic region projects and synchronizing them with American projects in order to create extra competition for Russian oil industry and for selling its products on the global market.Low global price for hydrocarbons and financial sanctions can exert more infl uence on the development of Russian Arctic fields than restricted access to equipment and technologies.

Abstract The automatic identification system (AIS) has become a key element in maritime domains of inquiry and the number of related articles has increased rapidly. The systematic integration of AIS data with other datatypes has received less attention and has mostly resulted in application-specific datasets that are small relative to the available AIS data. This work presents an accumulating multi-purpose database for the northern Baltic Sea that combines nine years of AIS data with marine environmental data. The main application is winter navigation research, for which purpose the environmental data is from ice charts and ice drift models. The AIS data is from terrestrial stations and amounts to 6 billion messages. It has a full update rate which is also required for the analysis of ice navigation as this involves close encounters, icebreaker assistance, convoy operations, and rapid speed changes. To identify and study such traffic features, distances between ships that are close to each other are included in the database. Application examples are given for spatial traffic statistics, reduction of ship speed with increasing ice thickness, and for icebreaker assistance. Graphical abstract Image 1 Highlights • Nine years of Baltic AIS data with a full time resolution has been integrated with marine environmental information products. • The integrated data is arranged into an accumulating database serving a wide spectrum of applications. • AIS data integrated with information used to analyze the winter navigation system and the ice performance of ships. [ABSTRACT FROM AUTHOR]

Abstract Ice accumulation on ships and offshore rigs creates unsafe working conditions and may damage critical equipment. Several approaches have been developed in the past to predict ice accumulation; these include analytical models, experimental investigations, computational fluid dynamics simulations, empirical and statistical models. This work proposes a probabilistic causal relationship-based model to predict ice accumulation on ships or offshore rigs. The model uses a Bayesian probabilistic approach to establish the relationships among the factors affecting icing. The model is successfully tested on an experimental set-up designed to simulate the spray icing condition observed on a seagoing vessel in the subzero environment. The results of the experimental tests were compared with the outputs from the predictive model. It was observed that the predicted values gave a reasonably good match with the observed values. The proposed model considered a range of environmental and process parameters that affect ice accumulation. The model has the flexibility to include more parameters affecting icing, based on location and system. The model can be used for dynamically changing conditions with minimal computational load and time. Highlights • A new probabilistic model to predict the ice accumulation on the ships or offshore rigs. • A network model demonstrating dependence of design, operational and environmental parameters. • A new experimental setup to simulate the spray icing condition observed in the subzero environment. • Testing and validation of the model using the experimental model. [ABSTRACT FROM AUTHOR]

Abstract The main objective of this study was to compare conditions for sedimentation in a lagoon in the presence and absence of ice coverage. The winter conditions of Vistula Lagoon (hydrology, suspended solids in water, ice, and snow) were studied during the period 2011 – 2016. Three-dimensional numerical modelling was used to simulate the water level variations and currents under ice coverage. Satellite images were collected to reproduce the ice-coverage cycle. In general, the hydrological and sedimentation conditions in the winter period without ice coverage were highly similar to those in the warm period of the year. The suspended sediment concentration was 22 – 32 mg/l. Ice cover eliminates wind forcing, and water exchange with the sea and river discharge become the main forcing factors. Strong vertical salinity stratification is established under ice, and river water intrusion spreads much further under ice in the lagoon area than in the absence of ice. The water level variation in the inlet is the main dynamic factor influencing the water motion under ice throughout the lagoon. Water level variations with a period of less than 12–24 h are damped by the ice cover, and oscillations with a period of longer than 1 day easily spread under the ice. The currents in the lagoon are characterised by vertical stratification with a maximum in the middle layer due to friction at the bottom and at the ice layer, currents are sufficient to produce re-suspension only in the vicinity of the inlet. In the absence of ice, the currents have maximums at the surface and in the near-bottom layer. The suspended solid concentrations under the ice cover (5–10 mg/l) are less than those in the summer (20–35 mg/l), and vertical distribution is characterised by two maximums: near the bottom and at the surface. The sedimentation rate under ice was experimentally estimated as 2–4 mm/year. During the ice period, the rivers are the single sediment sources, and most sediments settle in the close vicinity of the river mouths and are redistributed along the lagoon area only after the ice melt. Air-born sediments stored in the ice and snow cover (on the ice) contain particles of anthropogenic origin (ashes and soot), inorganic mineral substances and organic substances. Because it appears that most ice melts within the lagoon, the sedimentation peak is expected to occur in spring and is caused by both the increase of river inflow and melting of ice. Highlights • Water level variations with a period of less of than 24 h are damped by solid ice cover. • Currents display a maximum in the middle layer due to friction at the bottom and ice. • River water intrusions spread under solid ice cover much further than without it. • Suspended solid concentrations under solid ice cover are 5 – 10 mg/l. • The sedimentation rate under solid ice cove was experimentally estimated as 2 – 4 mm/year. [ABSTRACT FROM AUTHOR]

Abstract In northern sea areas such as the Baltic Sea and the Arctic, especially in winter conditions, the presence of sea ice frequently necessitates icebreaker assistance operations for vessels navigating in these areas. Icebreaker escort operations are important for ensuring the safety of navigation in these harsh environments. While these operations reduce the overall system risk, studies have shown that specific navigational risks are associated also with escort operations, necessitating appropriate training and operational support for ship crew engaged in these. In this paper, the icebreaker escort operations are investigated, and a ship-following model is proposed, drawing on similarities with the car following phenomenon. This ship-following model accounts for the necessity of keeping an appropriate safety distance to avoid collision, as well as for the effects of sea ice on the operation. Its main intended use is for implementation in maritime simulators, providing a realistic environment of operational conditions for training ship crews. As a first approximation, the model accounts for the ice condition by the average ice thickness, while the safety speed constraint is relative to the vessel's ability of navigating in ice. The model parameters are calibrated using empirical data of icebreaker escort operations. Case studies are executed, showing good agreement between the simulation model and real-world operational conditions. Highlights • A ship-following model for icebreaker escort operations is proposed. • Safety distance and the effects of sea ice on the operation are accounted for. • Main intended use of the proposed model is for implementation in maritime simulators. • The model parameters are calibrated using empirical data of icebreaker escort operations. • Case studies show good agreement between the simulation model and real-world operations. [ABSTRACT FROM AUTHOR]

This article is dedicated to permanent offshore platforms for working in ice conditions. The authors focus on creating constructions for working in ice conditions. The article presents drawings of ice-resistant permanent offshore platforms according to their attachment to the seabed. The article also describes the scheme of the general arrangement of the ice-resistant tetrahedral permanent offshore platforms.

The sedimentary cores from the southern and northern parts of the Chukchi Sea illustrate the influence of climate and environmental conditions on the chemical composition of bottom sediments accumulated at present and in the recent 500 years. The low concentration of biogenic (Ca, Br, Sr) and some redox-sensitive (Fe, Mn, Zn) elements is typical of the recent sediments accumulated in the areas with permanent ice cover and of the sediments accumulated during cold periods (Little Ice Age and especially the Maunder Minimum). The possibility is revealed of identifying cyclic changes in environmental conditions including sea ice extent in the concrete Arctic areas. This may be used to detail the regional forecast of future changes. [ABSTRACT FROM AUTHOR]

This article presents the variations in air temperature and humidity in the region of the Hornsund fjord for the period from 1 July 2014 to 30 June 2015. Based on measurements at 11 sites, it was established that significant topoclimatic differences were dependent on height above sea level, substrate type, distance from the sea, exposition, atmospheric circulation and the ice conditions. The thermal and humidity conditions of individual sites are presented in relation to the weather conditions at the Polish Polar Station in Hornsund (HOR). In the study period, the warmest annual mean air temperature occurred at Hyttevika (HYT), and the coldest on the summit of Fugleberget (FUG), respectively, +1.1°C and −3.7°C relative to HOR. Meanwhile, relative humidity differs from HOR values most strongly on Fugleberget, where it is greater by an average of 14%. Atmospheric circulation and ice cover were shown to have a significant impact on thermal and humidity conditions. The greatest spatial variations in air temperature (3.0°C) in Hornsund region (between HOR and FUG) occurred in winter during anticyclonic advection from the northern sector. The greatest difference in relative air humidity (20%) relative to HOR occurred in FUG in autumn during cyclonic advection from the eastern sector. The east-west thermal and humidity gradients along the fjord are more pronounced when sea ice is present. Differences in air temperature and relative humidity between the sites located in the inner (TRE) and outer parts of the fjord (HG4 and HYT) rose by about 2.0-2.5°C and 7-9%, respectively. [ABSTRACT FROM AUTHOR]

A possibility for using the promising multipurpose Arktika space system for the development and support of situational awareness of Arctic weather and ice conditions based on the network-centric principle is considered. This possibility became a reality when the analysis of synoptic conditions using remote sensing tools progressed from theoretical to practical use. [ABSTRACT FROM AUTHOR]

Transportation in ice prone waters is a timely topic due to the pursuit for arctic natural resources and sea routes. One important safety aspect in designing ships that enter ice prone waters is to determine the ice-induced loads on ships. However, ice is a particularly inconsistent material; therefore it is difficult to predict the occurring loads when the ship hull breaks the ice. We propose a novel probabilistic, Bayesian, method for modeling and predicting ice load distributions in different ice and operational conditions. We assume the ice loads to be generated from a random process whose parameters change as a function of ice thickness and ship speed. We test four alternative hierarchical Gaussian Process models. The best model shows good performance in predictive validation tests. According to the results the probability of high ice loads increases with increasing ice thickness and increasing speed. The model can be used to predict continuously ice loads in different ice thickness and speed conditions and, with further development, has potential to be utilized in determining the safe way to operate ships in different conditions. [ABSTRACT FROM AUTHOR]