Barents Sea Research Articles

Extensive glacitectonism and rapid deglacial fluid expulsion in the northeastern Barents Sea

High-latitude regions store large amounts of carbon trapped by ice sheets, permafrost and gas hydrates, yet joint evolution of these climate components is poorly understood. Covered by a cold-based ice-sheet during the last glaciation, the seafloor of the northeastern Barents Sea reveals one of the largest known glacitectonic provinces in the Arctic. Up to 200-m high glacitectonic landforms are cratered and overlie faults associated with ‘bright spots’ indicative of subsurface gas accumulations. However, sediment samples show low pore gas concentrations and no present-day gas seepage. We combine new observations and ice-sheet - hydrate modelling to propose that during the Late Weichselian, glacitectonism was caused by patchy substrate stiffening due to gradual growth of subglacial gas hydrates and permafrost. Ice decay led to rapid destabilisation and full drainage of shallow hydrate reservoirs and permafrost thaw, causing craterisation which was likely accompanied by large fluxes of carbon released into the water column. This study shows that these processes were more widespread across glaciated margins, also highlighting sensitivity and potential for abrupt changes of high-latitude carbon pools in response to complex interactions between the cryosphere, ocean, and solid earth.

Новые памятники археологии на северном побережье Кандалакшского залива Белого моря

The article is devoted to the results of the archaeological expedition of the Kola Scientific Center of the Russian Academy of Sciences on the northern shore of the Kandalaksha Bay of the White Sea near the city of Kandalaksha and on the Kolvitsa River in 2023. Three new archaeological monuments have been recorded: Niva XXIII — boulder pit, Kandalaksha XVI – charcoal pits and Kolvitsa – stone structures. The boulder pit is located on an ancient sea terrace, on the western slope of Mount Volosyanaya, 1 km from the Niva River. Three charcoal pits are located on the northern shore of Malaya Pitkulya Bay, near the southern slope of Mount Krestovaya, not far from the labyrinth. This is the first discovery of such objects in Russian Lapland and they date back to the late 15th–16th centuries. Seven formations of boulders are located on the northern bank of the Kolvitsa River near the rapids. Analogs are known to them in other places of Russian Lapland. There are also boulder pits on the Khlebnaya River and on the coast of the Barents Sea. The dating and ethnicity of the boulder structures are still speculative.

Effect of Hydrocarbon Pollution on the Fungal Communities of the White and Barents Sea Littoral Sediments

The effect of hydrocarbon pollution on the fungal communities of littoral sediments of the cold-water White and Barents seas was investigated. The samples were collected at locations with different levels of pollution with oil products, from ports to relatively undisturbed areas. Using the diesel fuel-containing medium resulted in detection of hydrocarbon-degrading fungi in almost all studied samples, although in all cases they were less diverse than sugar-degrading fungi. In this relatively small group, Penicillium chrysogenum and Penicillium brevicompactum were the most common organisms. Fungal communities isolated on a sugar-containing medium exhibited higher diversity and abundance, with being the most common sugar degraders. The major factors affecting the structure of the fungal communities were the percentage of hydrocarbons in the total mass of organic carbon in the samples in the case of hydrocarbon-degrading fungi and location, for sugar degraders. In the experiment, the highest hydrocarbon-degrading activity was shown for Penicillium chrysogenum (the loss of residual hydrocarbons was 77.4%), Cadophora fastigiata (72%), and Tolypocladium inflatum (67.2%).

Diet and trophic structure of fishes in the Barents Sea: Effects of size within (ontogenetic) and between species

A large data set on stomach content (over 27,000 individual fish) – collected in the Barents Sea in 2015 – was used to examine ontogenetic and interspecific changes in diet with size for 35 fish species. The analysis combined the use of hierarchical clustering and random forest. Two different diet metrics were used (% weight of prey types per weight of stomach content or per weight of fish, the latter reflecting also feeding intensity), and data were analysed based on average diet of predator groups (species and size groups) across the entire sample series (from the whole Barents Sea in different seasons), or for data broken down by geographical areas and seasons. Similar trophic groups (clusters) were identified for the various data sets suggesting that the results on trophic structure were robust. The trophic groups including size information were broadly similar to groups found earlier with data averaged at species level. Hierarchical clustering produces a hierarchy of trophic groups (or trophic guilds) at various levels of diet dissimilarity. With 12 clusters identified, one cluster had fish as dominant prey, and 5–6 others had either plankton or benthos as dominant prey. The clusters tended to be distinct and homogenous with one dominant prey category in average diet (often > 60 %). This was especially the case for the plankton clusters, with copepods, euphausiids, hyperiid amphipods, or gelatinous zooplankton as dominant prey in each of 4 trophic groups. The benthos clusters tended to be less dissimilar with more overlap in diet composition, with predominance of either hard-shelled forms (echinoderms and molluscs) or softer prey (polychaetes and crustaceans) for groups of clusters. There were clear patterns of ontogenetic shifts in fish diet. Fish that clustered as piscivores at larger size tended to grow from being planktivores when smaller. Smaller species of planktivores or benthivores shifted position among trophic groups but remained within the categories of planktivores or benthivores, respectively. Taxonomy (species) tended to be more important than size for explaining the diet composition of the different clusters of fish predators.

Прогнозирование углеводородоперспективных структур кольцевого вида в Баренцевоморском регионе по результатам применения стохастического метода при использовании совокупности геопараметров

The article presents the results of the application of the stochastic method used to predict hydrocarbon-prospective geostructures of a concentric type within the Barents Sea region. According to thecalculated values ofstochastic parameters for the 21 geostructures of aconcentric view in the waters of the Barents region, based on four different geoparameters a summary table of stochastic parameters was compiled and an encouraging forecast was made for 13 concentric geostructures promising for the search for new oil deposits within the Barents Sea region.

Features of the distribution and habitat conditions of cetaceans in the Barents Sea in the summer-autumn period 2004–2021

The aim of the paper is to identify the features of distribution of cetaceans in ice-free areas of the Barents Sea and adjacent waters in August-November and to characterize their habitat conditions (abiotic factors, distribution relative to mass fish species and macroplankton).The material of the study was the data collected by the Polar branch of VNIRO during the joint RussianNorwegian ecosystem surveys.Methods: geoprocessing and mapping of the studied parameters, comparative and statistical (principal component and correlation) analysis of the data.Results: Cetaceans were mainly observed in the western Barents Sea and distributed in waters with depths of from 23 to 2294 m, at temperatures of –1.9…10.7 °C and salinities of 33.0–35.2, the weighted averages of these parameters were 265 m, 3.1 °C and 34.7 respectively. Minke whales, fin whales, humpback whales, whitebeaked dolphins, killer whales, and porpoises were observed in waters with wide ranges of temperature and salinity, while blue whales and sperm whales were observed in waters with narrow ranges of these parameters. The lowest weighted average water temperature (0.3 °C) and salinity (34.4) were typical of humpback whale. Minke whale, fin whale, humpback whale and white-beaked dolphin had the largest overlap in their distribution with that of possible preys. Statistical analysis showed that priority preys for these cetaceans could be capelin and polar cod for the studied period. In addition, one of the possible preys for baleen whales was also macroplankton, and for the white-beaked dolphin — cod, blue whiting and redfishes.Practical significance: The results of this study can be used in studying the ecology of cetaceans in the Barents Sea, in assessing their impact on stocks of commercial fish species, as well as in ecosystem modeling.

On the prospects of fishery of the Barents Sea red king crab within the coastal waters of Russia

Objective: to review the current state of the red king crab stocks in the Barents Sea off the coast of the Kola Peninsula and propose options for optimizing their use.Method: the work is a review of the state of stocks, biology and fishing regime of the red king crab in the Barents Sea coast, based on previously published research results. In addition, unpublished survey data with appropriate explanations were used.Novelty: the review contains information relevant for the summer of 2023 on the fishing regime of the red king crab in coastal waters, examines the prospects for the exploitation of stock of king crab in connection with changes in legislation that occurred in 2023.Results: the coast of the southern part of the Barents Sea is of high importance for the reproduction of the red king crab population and can be considered as a reserve for its fishing in the EEZ of Russia. Among all the sections of the Barents Sea coast, Varanger-Fjord, as the most remote from the area of modern fishing area, is promising for the resumption of crab production in it. In addition, fishery the red king crab in the western part of coast of the Barents Sea will provide additional data on the impact of fishing on the stock, which will be used in fisheries management. In the near future, it is advisable to consider the possibility of changing the by-catch limit for non-commercial individuals when mining in the coastal area, as well as the possibility of allocating the Varanger-Fjord the red king crab as a separate management unit within a single reserve. Prior to receiving new data, it is possible to recommend that no more than 0.6 thousand tons of the red king crab in the Varanger-Fjord area.

Acoustic observations of walleye pollock (Gadus chalcogrammus) migration across the US-Russia boundary in the northwest Bering Sea

Abstract The degree to which walleye pollock (Gadus chalcogrammus, hereafter pollock) move between the US and Russian zones of the Bering Sea is a key source of uncertainty for fisheries management. To study transboundary migrations across the US–Russia maritime boundary and explore how climate variability might influence these migrations, four seafloor-mounted echosounder moorings were deployed from July 2019 to August 2020 in the northwestern Bering Sea. The observations indicated that a substantial amount of pollock moves between the US and Russia seasonally, with a period of southeast movement into the US as winter as sea ice forms and northwest movement into Russia in early summer as waters warm. Over the deployment period, 2.3-times more pollock backscatter moved into the US zone in fall and winter than exited the subsequent spring and summer. We hypothesize that the difference in the net movement between regions was driven by pollock moving farther into Russia during the historically warm conditions at the start of deployment period and reduced northwest return migration the following summer when temperatures were relatively cooler. This supports the hypothesis that temperature affects pollock distribution, and that continued warming will lead to a larger proportion of the stock in Russian waters.

Biological characteristics of the Pacific halibut in the Bering Sea and off the eastern coast of Kamchatka in spring 2022

The purpose of the work: to give a biological characteristic of the Pacific halibut in different areas of the Bering Sea and off the eastern coast of Kamchatka and to analyze its size age composition in catches of trawl fishing. Methods used: the material was collected during the expedition research, a complete biological analysis of the Pacific halibut was carried out, the otoliths were selected to determine the age. The age was determined in accordance with the guidelines developed specifically for the Pacific halibut in the International Commission on Pacific Halibut (International Pacific Halibut Commission, IPHC).Novelty: the elements of novelty are generalized and analyzed data on Pacific halibut. The material collected in the waters of Eastern Kamchatka and the Bering Sea in 2022. Pacific halibut from trawl catches have been studied, its biological characteristics have been considered, the size-age composition and growth rate have been analyzed.Practical significance: the results of these studies can be used in forecasting the stocks of Pacific halibut in this area.Result: data on catches of Pacific halibut in different regions of the North West Pacific Ocean, the size and age composition, a comparative characteristic of males and females by growth rate, the age composition of fish by maturity stages.

Predator biomass affects west–east shifts in Barents Sea capelin (Mallotus villosus) spawning ground use

AbstractSpawning locations of migratory fish influence the environmental and oceanographic fate of eggs and larvae. However, we have an incomplete understanding of how and why realized spawning locations vary. We quantified the yearly variation in spawning location for Barents Sea capelin (Mallotus villosus) within the recognized spawning areas along the coast of northern Norway and Murman. Furthermore, we tested whether water temperature, sea ice cover, predation and capelin fisheries are associated with spawning locations. Estimated spatial variation in spawning longitude used data from Soviet‐Russian ichthyoplankton surveys from 1959 to 1993 and a bootstrap procedure. The mean spawning area along the coast was then calculated by combining larvae observations with backtracking a larvae drift model from potential spawning areas. We fitted a generalized additive model (GAM) to assess the effects of environmental conditions on these drift‐corrected spawning longitudes. Capelin's mean yearly spawning location varied substantially across the study period. An increase in immature cod biomass, a major predator of capelin, during the spawning migration period in winter and early spring corresponds to more eastward capelin spawning. The eastward shift in mean spawning longitude seems to reach an eastern limit at high immature cod biomass. Sea temperature, sea ice cover and capelin fisheries were not associated with mean capelin spawning longitude. We show that the realized spawning areas for capelin are related to cod biomass, potentially through cod predation depleting and/or acting as a migration barrier for mature capelin.

Principles of landscape-bionomic zoning of the Barents Sea

Landscape-bionomic zoning reveals the effect of hydrological and geomorphological links of the physical-geographical process on the bionomic differentiation of the Barents Sea floor. The polar front separates the Arctic water masses and communities from the subarctic ones; under the influence of warm Atlantic Current branches, extrazonal boreal biomes are formed. The geomorphological structure represents the lithogenic basis that determines the formation of bionomic types of the Barents Sea floor. It was established that each geomorphological region corresponds to one macrozoobenthos group.

Anthropogenic iodine-129 tracks iodine cycling in the Arctic

Global warming has accelerated the iodine cycle in the Arctic Ocean, amplifying its significance in the global iodine cycle. However, some intricacies of the iodine cycle in the Arctic marine environment remain unclear. In this study, we present concentrations of stable- and radio-iodine (127I and 129I) in total iodine, iodide (I–), and iodate (IO3–) in seawater from the Beaufort, Chukchi, and Bering Seas. Results show a wide range of 129I/127I ratios of total iodine (3.2 × 10–12–9.3 × 10–9), indicating that the total 129I/127I ratio is a valuable fingerprint for identifying water masses and comprehending mixing processes. Iodine loss in surface seawater was quantitatively assessed using 129I, revealing that Arctic rivers substantially contribute to the emission of iodine into the atmosphere from the Arctic and subarctic seas. Our redox simulation in the Arctic intermediate layer shows the concentrations and 129I/127I ratios of I– and IO3– during its migration and provides the first evidence of an IO3– reduction process masked by the I– oxidation in the intermediate Arctic Ocean. Oxidation and reduction processes in the intermediate Arctic Ocean were characterized by extremely slow rates, at 0.95–2.41 and 0.26 ± 0.13 nM/year, respectively. Our findings demonstrate the effectiveness of anthropogenic 129I in tracking iodine cycling in the Arctic marine environment.

Latitudinal variations of iron chemical speciation in the euphotic zone of the central Pacific Ocean

The concentrations of dissolved iron (DFe), iron-binding ligands (LFe), and electroactive humic-like substances (eHS) were revealed in the upper 200 m along the 170°W latitudinal transect of the central Pacific Ocean in summer, which was weakly influenced by terrestrial input. DFe was largely depleted throughout the transect, except in the Bering Sea, and below 100 m in the North Pacific Subarctic Gyre. The concentration of LFe was lowest within the subtropical gyres and was lower in the Southern Hemisphere, which is consistent with the results from the Atlantic Ocean. The vertical distribution of LFe was relatively constant in the subtropical regions, whereas in the subarctic regions the subsurface maximum appeared around or over the subsurface chlorophyll maximum at some stations. The higher concentration of LFe in the subarctic regions coincides with a lower stability constant, which suggests a higher contribution of weaker ligands, including humic and exopolymeric substances. The horizontal and vertical distribution patterns of eHS were largely similar to those of LFe, supporting their significant contribution to iron-binding capacity in the upper 200 m, particularly in the subarctic regions. However, the eHS concentration was only weakly correlated with that of the fluorescently determined humic-like substances, demonstrating the substantially different chemical properties of the two humic-like substances. The strong positive correlation between the concentrations of eHS and chlorophyll a and Synechococcus strongly suggests their biological origins. However, further research is required to examine whether eHS are directly produced by phytoplankton or released via relevant biological processes, such as grazing, bacterial composition, and viral lysis.

Whole genome resequencing of sablefish at the northern end of their range reveals genetic panmixia and large putative inversions

Abstract Sablefish (Anoplopoma fimbria) are a highly mobile species that support important commercial fisheries in the North Pacific Ocean. Information on the genetic stock structure of sablefish is vital for constructing management strategies that ensure the long-term viability of the species. Most previous genetic studies on sablefish have found panmixia throughout the majority of their range, but a recent study suggested that a population structure may exist. Here, we use low-coverage whole genome resequencing to investigate genetic structure in the northern end of the species’ range (from Washington State, USA to the Bering Sea and Aleutian Islands, AK, USA). Additionally, we reanalyzed an existing genomic dataset containing 2661 markers to test specific hypotheses about genetic structure by sex. Genome resequencing data from 119 individuals screened at 7 110 228 markers revealed no evidence of population structure, and reanalysis of the existing genomic dataset supported the same conclusion. Differentiation across the genome was largely driven by variation at two putative inversions located ∼1 megabase apart, which did not display any signals of geographic differentiation. Our study further supports the conclusion of genetic panmixia in sablefish throughout its northern range.

PERFORMANCE ASSESSMENT OF DATA-DRIVEN MODELS IN ARCTIC SEA ICE PREDICTION

Data-driven models are emerging as a brand-new approach in Arctic sea ice prediction. In this study, we perform the effectiveness comparison of different machine learning models in predicting the sea ice extent in the whole Arctic Sea and its subregions: the Bering Sea, the East Siberian Sea, the Chukchi Sea, the Beaufort Sea, and the Central Arctic Sea. The machine learning models used in this study include Ridge Regression, Lasso Regression, Decision Tree, k-Nearest Neighbors, Random Forests, XGBoost, as well as two stacked learning models. Our research reveals that due to the different features of sea ice evolution in different sea areas, these data-driven models generate significantly different prediction performances for sea ice evolution in different seas. In detail, two stacked learning models performed the best in the whole Arctic Sea, the stacked learning model LR_Random Forests performed the best in the Beaufort Sea, Bering Sea, and Chukchi Sea, the Random Forests model performed the best in the Central Arctic Sea, and the Decision Tree model performed the best in the East Siberian Sea.

Air Composition over the Russian Arctic–4: Atmospheric Aerosols

This work presents the analysis of the spatial distribution of number concentration, size distribution, and chemical composition of aerosol particles measured for the first time over the seas of the Russian Arctic. Various types of vertical distribution of the number concentration were recorded, characteristic of both coastal marine and continental areas. Most of them turned out to be of the continental type. Attention is also drawn to the almost complete absence of coarse particles above 2–3 km over all seas. The chemical composition of the Arctic aerosol at altitudes of both 200 m and 5000 m contains ions that can be referred to as both marine and continental. The identifiable carbon- and salt-free elemental part of the aerosol over the Arctic is 3–4 times larger than that of ions. Over all seas and at both altitudes, the Arctic aerosols mainly contain elements of terrigenous origin – Al, Cu, Fe, and Si. Over almost all seas, except the Barents Sea, Si is dominant in the elemental composition of the aerosol, its contribution over the Chukchi Sea reaching 85%. The analysis of backward trajectories showed that in all cases considered, whether the aerosol was formed over the continent or sea, air trajectories passed both over sea and over land. In this case, the formed particles could be enriched with additional ions and elements along their pathway. This work completes a cycle of the papers, devoted to studying air composition, which was carried out over the seas of the Russian Arctic in September 2020. Our results can be used to model the atmospheric processes occurring in the Arctic under the conditions of changing climate.

Influence of Microbial Activities on Fluorescent Dissolved Organic Matter in the Dark Canada Basin Waters

AbstractThe fluorescence characteristics of dissolved organic matter (DOM) were measured to determine the distribution and drivers of DOM in the dark Canada Basin waters. We studied the relationship between fluorescent DOM (FDOM) and apparent oxygen utilization (AOU) in the whole water column as well as in the main water masses (Pacific Winter Water, Atlantic halocline (AH), Atlantic water—Fram Strait and Barents Sea branches, Deep Temperature Minimum, and Canada Basin deep water). The relative water mass fractions of different water masses were estimated using a five end‐members mixing model. The distribution of water mass fractions was found to be in good agreement with the distribution based on the traditional temperature‐salinity diagram. The fractions of AH waters were linked with AOU, highlighting the significant role played by mineralization in shaping AH humic‐like levels. The slope of the relationship between in situ FDOM—AOU was greater than those reported in the other oceans worldwide. This suggests that the AH is a hot spot for microbial mineralization of humic‐like DOM. On the other hand, the relationships with the humic‐like intensities differed among the four humic‐like components in the >125 m waters, indicating distinct environmental dynamics and biogeochemical roles for each humic‐like component.

Керамика древнеберингоморской культуры со стоянки возле утеса Кожевникова (мыс Шмидта): особенности технологии

During the excavations of a dugout at the Kozhevnikov Cliff site (Cape Schmidt), N.N. Dikov obtained a collection of pottery vessels of the Old Bering Sea culture (fourteen specimens). The technology of ceramic production was analyzed using the methodology developed by A.A. Bobrinsky. It was determined that potters selected iron-rich clays of two subtypes, differing in the amount of natural sand content, for pottery production. Five recipes for the molding clay were identified, including three unmixed: 1) clay + sand (7 specimens); 2) clay + wool (3 specimens); 3) clay + organic solution (2 specimens); and two mixed – 4) clay + sand + organic solution (1 specimen); and 5) clay + sand + wool (1 specimen). The vessels were made in a base form, and the shape was additionally formed by paddling. On the outer surface of one artifact, a strap handle with an ear for threading a cord was made, and the remaining hole on the inside was patched with a cloth scrap. The surfaces of the vessels were treated by mechanical smoothing with a hard-smooth tool and/or fingers. Firing took place at temperatures above clay calcination and could be done in bonfires or hearths. The heterogeneity of pottery traditions was found among the population living in the dugout. The two identified two-component recipes for molding clay were formed as a result of mixing the adaptive pottery skills of bearers of different traditions of making unmixed recipes for molding clay. This indicates the beginning of cultural integration processes among bearers of different pottery skills that began to occur under the dominance of the tradition of using low-sanded clay of the first subtype and artificial sand addition in a 1 : 1 concentration.

Sources of Freshwater Components in Western Part of the Bering Sea According to Isotope (δ18О, δD) Data

Sources of Freshwater Components in Western Part of the Bering Sea According to Isotope (δ18О, δD) Data

Recent Thickening of the Barents Sea Ice Cover

AbstractThe Arctic sea ice cover has decreased rapidly over the last few decades both in extent and thickness. Here we present multi‐year (2013–2022) observations of sea ice thickness in the northwestern Barents Sea based on Upward Looking Sonar measurements and show that the winter sea ice has become thicker over the last decade. Sea ice thickness from the Pan‐Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) reproduces both the observed variability and recent 10‐year trend and shows that this thickening (0.24 m decade−1) has not been seen since the 1990s. Using PIOMAS we find that the recent increase in sea ice thickness can be explained by increased sea ice freezing as a result of lower temperatures in the ocean and in the atmosphere. The recent thickening is set in the context of a long‐term thinning trend, with PIOMAS showing much thinner ice now than in the 1980s.