The paper introduces the problem of the use of mathematical modeling results in the preparation of measures to ensure environmental safety of offshore oil and gas projects. Incremental approach to the selection of critical scenarios of oil spills spreading in the sea is chosen as a key principle of forming a subset of variants of the accident development. Consistent application of the selection criteria allows selecting the critical scenarios to analyze the effectiveness of various response strategies, which provide a level of readiness of forces and resources sufficient to ensure environmental safety with an acceptable level of risk.

This report is a continuation of the study of H. antarcticus by authors published in the previous issue of this magazine. On our and literary data on the most southern representative of the genus Harpagifer – H. antarcticus from the western coasts of the Antarctic Peninsula and the neighboring waters of the archipelagos of the Western Antarctic a descriptions of biological and ecological peculiarities are given as the only species of the genus inhabiting both littoral and upper sublittoral zones (up to 100 m depth). The base of our materials consists of fishes collected at the Russian Antarctic station Bellinsgausen in 2006–2011. Also distribution patterns and problems of the origin of the species from possible ancestor form inhabited in near coast waters of the pacific sector of the Antarctic and the south parts of the South America up to their division are considered and discussed. The problems of “advance” of harpagifer ancestor, its origin and speciation independent on far distant subantarctic islands and some causes of impossibility to occupy coast waters of the Continental seas of the Eastern Antarctic are discussed.

The method of vector analysis of variance of vector random processes was used for the description of annual and tidal variability of sea currents in the Pechora Sea.

There are the cases for description of temporal and spatial variability of sea currents.

This paper presents computation possibility of basic air-bubbles barbotage parameters. The frequency of air-bubble breakaway and its size are the basic characteristics of the barbotage. Mathematical expressions of the breakaway frequency and of air bubble size were founded on base of dimensions analysis. Ascent velocity of air bubbles is related to their size. The stationary solution of the momentum equation and the automodel conditions relatively viscosity of water is regarded for determining the ascent velocity.

It is shown that the organic-mineral deposits are a specific kind of the coastal zone deposits, the formation of which is due to sea-level changes in the past. These deposits are unique not only in the Arctic, and in one form or another be found everywhere, that is, are the result of sedimentation processes in the coastal zone of the sea, which manifests itself at the global level. Their formation is directly related to changes in sea level, and therefore, these deposits are an excellent indicator of the change in the position of the sea level in the past. It should be noted that during the Holocene were several stages of accumulation of sediments 6–8, 4, and 1,2–1,5 thousand years ago, indicating a possible change in the level of the Global Ocean in these time periods. It turns out that the organic-mineral deposits have great potential as an indicator of the position of the sea level in the past.

In the report an approach to developing technology to create digital elevation models of the seabed using heterogeneous data is considered. The technology was tested on material hydrographic work carried out by domestic and foreign researchers in the Central Arctic Ocean with drifting ice, surface ships and submarines. The necessity of systematic analysis of different quality bathymetric information varying by level of reliability when creating common databases and digital models is justified.

Based on the data of automatic “Argos” buoys, the frequency of occurrence of the monthly fields of ice drift velocity with presence of the anticyclonic eddy in them was calculated for the annual ice cycles. It was determined that at close values of the frequency of occurrence for different years, the drift velocity fields are also identical to each other in many aspects. On this basis the total number of years with initial data is divided into three groups by the value of the frequency of occurrence. The prognostic calculation of ice motion is performed by the monthly fields of the group the values of the frequency of occurrence of which will correspond to a greater extent to the frequency of occurrence of the current annual ice cycle. The article presents information on the basis of which the choice of the analogous group of years is presented. Technology of the prognostic ice motion calculation by the monthly drift velocity fields for the chosen analogous years is given. The results of determination of the skill score and efficiency of the method obtained taking into account the ellipse of permissible error are presented.

The methods and results of determining the highest water level and zero mark of Panaevsk station (at the Ob river delta) are presented. Were used observations of water levels at stations of Aksarka, Salemal, Salekhard, Panaevsk, Yamsalski bar, Yar-Sale, and also the water discharges of Ob river near Salekhard. It was found that zero mark of Panaevsk station in the first approximation can be taken equal –0.86 m (BS) and the height of maximum water level spring flood with probability 1 % is equal 3.54 m (BS). The obtained results are of interest to users by regime data at planning, building and exploitation of economic objects in the Panaevsk station area. They can also be used in the course of Water cadastre business.

The noticeable changes in cryological complex (submarine permafrost formations, ice-covered banks) in the coastal zone of the Laptev and East Siberian Seas are accompanied by export of organic matter into the sea. The degradation of subaqueous permafrost formations roof rock has been observed. The average cover rate fall for the entire period of thawing is in the range of millimeters to 40 centimeters per year. Cryogenic relief-forming processes (termoabroziya, thermoerosion, etс.) on the Eastern Siberia Sea coast lead to a reduction of coastal land annually by 10–11 km². The average rate of shore retreat is 5.1m / year and not more than 10m / year. The maximum values can reach 25 m / year. The acceleration of thermoabrasive shores destruction occurred in the period from 2000 to 2009. The sediment and organic matter flowing down to the Laptev Sea and East Siberian Sea is 62 and 90 million tons of precipitation and 1.6 and 2.4 million tons of organic carbon per year. The expedition studies in 2016 on the basis of the research station “Ostrov Samoilovsky” included drilling, GPR survey on the drilling profiles at the Lena River delta. Drilling depth is 24 meters. When drilling of underflow thawed soil through the water column of 7–9 m, the long-term (about an hour) methane outburst was observed.

For the first time representation of polar lows in the Arctic System Reanalysis (ASR), which was created specifically for the Arctic region, is estimated and compared to that of ERA-Interim. As obtained, ERA-Interim and ASR, correspondingly, resolve 48 and 89 % of cases from a widely used polar low list. The fraction of polar lows resolved by ASR is therefore considerably higher than was reported for other reanalyses in previous studies. ASR sea surface wind speed data were shown to be in good agreement with satellite-derived estimates. This is in contrast to ERA-Interim which significantly underestimates wind speed in polar low situations. As found, usage of an alternative polar low list leads to notable changes in the resulting estimates. As estimated for a more complete polar low list, polar low representation in ERA-Interim and ASR decreased to 26 and 66 %, correspondingly. Atmospheric static stability criterion was found to influence resulting percentages as well.