scholarly journals Free Short-Period Internal Waves in the Arctic Seas of Russia

2020 ◽  
Vol 37 (6) ◽  
Author(s):  
А. A. Bukatov ◽  
N. M. Solovei ◽  
E. A. Pavlenko ◽  
◽  
◽  
...  

Purpose. The aim of the work is to investigate vertical structure and phase characteristics of free shortperiod internal waves (IW), and to assess their dependence on density stratification in the Barents, Kara, Laptev and East Siberian seas. © Букатов А. А., Соловей Н. М., Павленко Е. А., 2021 МОРCКОЙ ГИДРОФИЗИЧЕСКИЙ ЖУРНАЛ том 37 № 6 2021 645 Methods and Results. Solving the main boundary problem of the Sturm-Liouville theory has resulted in calculating the amplitudes of velocity vertical component, own frequencies and periods of the first mode of internal waves. The density field was calculated using the reanalysis data (World Ocean Atlas 2018) on temperature and salinity for 1955–2017 with a resolution 0.25°× 0.25°. The relation between the internal waves’ vertical structure and dispersion features, and the density depth distribution was analyzed. It is shown that the averaged over the sea area depth of the maximum amplitude of the IW velocity vertical component in the Barents and Kara seas is ∼ 90 m in the mid winter and ∼ 75–80 m in summer, and in the Laptev and East Siberian seas – ∼ 60 m throughout the whole year. Conclusions. In the months when the density gradients are maximal, the internal waves of the highest frequency and the shortest period are observed. The maximum water stability in the Barents Sea takes place in July – August, in the Kara Sea – in July – September and November, in the Laptev Sea – in June, November, and in the East Siberian Sea – in July. Just in the same months, the maximum values of the averaged own frequencies, and the minimum values of the averaged own periods and amplitudes of the vertical component of the internal waves’ velocity are observed.

2021 ◽  
Vol 11 (2) ◽  
pp. 16-177
Author(s):  
A.A. Ershova ◽  
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T.R. Eremina ◽  
A.L. Dunayev ◽  
I.N. Makeeva ◽  
...  

The pollution of the seas in the Russian Arctic zone with micro-plastic particles is poorly studied in comparison with other areas of the World Ocean. The rapidly developing economic activity in the Arctic region threats to pollute the marine environment with plastic wastes. Arctic marine ecosystems are particularly vulnerable due to changes occurring in them under climate warming, as well as a large number of filter-feeder species in some coastal areas. The lack of observation data on the level of micro-plastic pollution in the region and methodological support for sampling requires the development of methods and approaches using the existing international experience. The paper presents preliminary results of the study carried out within the framework of the 4th stage of the TRANSARCTICA-2019 program in the Far Eastern and Arctic seas from Vladivostok to Murmansk. The authors present the analysis of existing approaches to sampling in seawaters and the possibility of their application in Russian expeditionary conditions. They describe in detail their method of sampling from a subsurface level (4—5 m) showing the advantage of using the proposed method for sampling when the vessel is moving and under adverse weather conditions. The studied quantitative and qualitative composition of the detected micro-plastic particles show that the East Siberian and Laptev seas have the lowest concentrations of micro-plastics. The largest amount of micro-plastic particles is found in the areas of intensive shipping in the Sea of Okhotsk and the Barents Sea. Comparison with existing international studies shows that the sampling method for micro-plastics strongly depends on the type of water body, its biological productivity, the level of pollution, as well as the technical capabilities of field research. All this indicates the need for intercalibration of sampling methods and further research for a more accurate quantitative and qualitative assessment of the micro-plastic pollution in the Arctic seas.


2021 ◽  
Vol 49 (2) ◽  
pp. 155-163
Author(s):  
S. M. Shapovalov

March 15, 2021 Chief Researcher, Head of the Laboratory of Hydrological Processes of the P.P. Shirshov Institute of Oceanology of the Russian Academy of Sciences, DSc, ex-president of the International Association for Physical Ocean Sciences (IAPSO) Evgeny Morozov is 75 years old. E.G. Morozov is a prominent scientist and organizer of world-class science in the field of studying the temporal and spatial variability of hydrological processes and internal waves in a wide range of scales. He was the first to build a map of the amplitudes of tidal internal waves of the World Ocean. His monograph “Oceanic Internal Waves” published in 1985 in Russian, as well as his article “Semidiurnal internal wave global field”, published in the Deep Sea Research in 1995, are among the most cited on the problem of internal tidal waves. Unique results were obtained by E.G. Morozov in the study of internal waves in the Arctic, including under the ice and near the front of glaciers sliding into the ocean on Spitsbergen. He made a significant contribution to the study of various currents: the Gulf Stream, the Kuroshio and their rings, the Antarctic Circumpolar Current, the California Current, the Falkland Current, the Lomonosov and Tareev subsurface equatorial currents. Since 1999 he has been a member of the Executive Committee of the International Association for the Physical Sciences of the Ocean (IAPSO) and since 2011 he has been elected President of the IAPSO, represented the IAPSO in this capacity on the Executive Committee of the International Geodetic and Geophysical Union (IUGG) and on the Executive Committee of the Scientific Committee on Oceanic research (SCOR). E.G. Morozov is the chairman of the Ocean Physical Sciences Section of the National Geophysical Committee of the Russian Academy of Sciences.


2021 ◽  
Author(s):  
Elena Popova

<p>Such factors as climate, currents, morphology, riverine input, and the source rocks influence the composition of the sediments in the Arctic Ocean. Heavy minerals being quite inert in terms of transport can reflect the geology of the source rock clearly and indicate the riverine input. There is a long history of studying the heavy mineral composition of the sediments in the Arctic Ocean. The works by Vogt (1997), Kosheleva (1999), Stein (2008), and others study the distribution of the minerals both on a sea scale and oceanwide. The current study covers Russian shelf seas: Barents, Kara, Laptev, East Siberian, and Chukchi Seas. To collect the material several data sources were used: data collected by the institute VNIIOkeangeologia during numerous expeditions since 2000 for mapping the shelf, data from the old expedition reports (earlier than 2000) taken from the geological funds, and datasets from PANGAEA (www.pangaea.de). About 82 minerals and groups of minerals were included in the joint dataset. The density of the sample points varied significantly in all seas: 1394 data points in the Barents Sea, 713 in the Kara Sea, 487 in the Laptev Sea, 196 in the East Siberian Sea, and 245 in the Chukchi Sea. These data allowed comparing the areas in terms of major minerals and associations. Maps of prevailing and significant components were created in ODV (Schlitzer, 2020) to demonstrate the differences between the seas and indicate the sites of remarkable changes in the source rocks. Additionally, the standardized ratio was calculated to perform quantitative comparison: the sea average was divided by the weighted sea average and then the ratio of that number to the mineral average was found. Only the minerals present in at least four seas and amounting to at least 20 points per sea were considered. As a result, water areas with the highest content of particular minerals were detected. The ratio varied from 0 to 3,4. Combining the ratio data for various minerals allowed mapping specific groups or provinces for every sea and within the seas.</p><p> </p><p>Kosheleva, V.A., & Yashin, D.S. (1999). Bottom Sediments of the Arctic Seas. St. Petersburg: VNIIOkeangeologia, 286pp. (in Russian).</p><p>PANGAEA. Data Publisher for Earth & Environmental Science https://www.pangaea.de/</p><p>Schlitzer, R. (2020). Ocean Data View, Retrieved from https://odv.awi.de.</p><p>Stein, R. (2008). Arctic Ocean Sediments: Processes, Proxies, and Paleoenvironment. Oxford: Elsevier, 602pp.</p><p>Vogt, C. (1997). Regional and temporal variations of mineral assemblages in Arctic Ocean sediments as a climatic indicator during glacial/interglacial changes. Berichte Zur Polarforschung, 251, 309pp.</p>


2021 ◽  
pp. 179-194
Author(s):  
I.O. Dumanskaya ◽  

The warming of the Arctic, especially intensified at the beginning of the XXI century, is accompanied by a significant decrease in the area of ice cover in the Arctic seas. The article shows the quantitative changes in the ice parameters of the Barents Sea, as well as factors affecting the formation of ice cover in recent years. In the twenty-first century the frequency of occurrence of mild winters has increased by 17%, the frequency of severe winters has decreased by 19%. Significantly increased the temperature at the meteorological station Malye Karmakuly, water temperature at transect "Kola Meridian", atmospheric and oceanic heat fluxes, and speed of sea currents on the Western border of the Barents sea. The duration of the ice period decreased by an average of 2–3 weeks, and the rate of reduction of ice cover was 7.2% for 10 years. This is the highest speed compared to other Arctic seas. The article shows that the variability of the ice cover of the Barents Sea and other parameters of the natural environment in the region has the cyclic character. Presumably, the cycle period is close to 84 years, which corresponds to the orbital period of Uranium. The minimum sea ice extent after 1935–1945 is expected in the period 2019–2029.


Zootaxa ◽  
2018 ◽  
Vol 4508 (3) ◽  
pp. 427
Author(s):  
IVAN O. NEKHAEV

Five species of the family Cancellariidae are currently known from Arctic seas: Admete contabulata Friele, 1879, A. clivicola Høisæter, 2011, A. solida (Aurivillius, 1885), A. viridula (Fabricius, 1780) and Iphinopsis inflata (Friele, 1879) (Golikov et al. 2001; Kantor & Sysoev 2006; Høisæter 2011). Admete contabulata, A. clivicola and Iphinopsis inflata are only known from the Atlantic part of the Arctic, i.e. Norwegian and southwestern Barents seas (Høisæter 2011; Nekhaev 2014). Admete solida has been rarely reported since its first description from the Bering Strait (Sysoev & Kantor 2002), however Nekhaev & Krol (2017) recently reported a specimen from the eastern region of the Barents Sea that is similar in morphology to the holotype of this species. Admete viridula is the only representative of Admete reported from Siberian seas (Golikov et al. 2001; Lyubin 2003; Kantor & Sysoev, 2006). 


2021 ◽  
Author(s):  
Anfisa Berezina ◽  
Evgeniy Yakushev ◽  
Boris Ivanov

<p><span>Currently, all natural environments, including the Arctic seas, are contaminated by microplastics (MP, plastic fragments less than 5 mm). Biogeochemical processes significantly affect the physical properties of MP, primarily its density due to biofouling.<br>The aim of this work is to develop a numerical model for assessing the fate of MP in the marine environment under the influence of natural biogeochemical cycles in the Arctic seas on the example of Oslofjord.<br>The biogeochemical model OxyDep (E. V. Yakushev et al., 2011) was used to reproduce the temporal variability of the phyto- and zooplankton, dissolved and particulate organic matter. The two-dimensional 2D benthic-pelagic transport model (2DBP), which considers the processes in the water column and bottom sediments together, is used as a hydrophysical model.<br>The separate module which describes the transformation of the MP under biogeochemical processes was developed. The biogeochemical and MP modules were coupled with the transport model using the Framework for Aquatic Biogeochemical Modeling (FABM) (Bruggeman & Bolding, 2014).<br>The results show, that there would be a decrease in the MP content in the surface layer in summer period due to the ingestion by zooplankton and its transfer to the sediments. Based on the obtained patterns, it is possible to predict zones of accumulation of MP for a specific water area, depending on the local ecosystem.</span></p><p><span>Funding: The reported study was funded by RFBR, project number 20-35-90056. This work was partly funded by the Norwegian Ministry of Climate and Environment project RUS-19/0001 “Establish regional capacity to measure and model the distribution and input of microplastics to the Barents Sea from rivers and currents (ESCIMO)” and the Russian Foundation for Basic Research, research project 19-55-80004.</span></p>


2021 ◽  
pp. 25-43
Author(s):  
A.E. Rybalko ◽  
◽  
M.Yu. Tokarev ◽  

Hot questions in the modern Quaternary geology of the Arctic seas associated with their glaciation are discussed in this article. The questions of the history of the occurrence of the problem of shelf glaciation or “drift” accumulation of boulder-bearing sediments are considered in detail. The results of seismic-acoustic studies and their interpretation with the aim of seismic stratigraphic and genetic partition of the cover of loose sediments of Quaternary age are considered in detail. Arguments are presented in favor of the continental origin of glaciers (Novaya Zemlya, Ostrovnoy and Scandinavian), which in the late Neopleistocene spread to the shelf of the Barents Sea and occupied its surface to depths of 120−150 m. Further development of glaciation was already due to the expansion of the area of shelves glaciers. The facies zoning of glacial-marine deposits is estimated, which is related to the distance from the front of the glaciers. It is concluded that already at the end of the Late Pleistocene, most of the modern Barents Sea was free from glaciers and from the annual cover of pack ice. Data on the absence of the area distribution of frozen sediment strata within the modern Barents Sea shelf are presented.


2016 ◽  
Vol 97 (8) ◽  
pp. 1605-1616 ◽  
Author(s):  
Alexey V. Golikov ◽  
Rushan M. Sabirov ◽  
Pavel A. Lubin

Studies on the quantitative distribution of cephalopods in the Arctic are limited, and almost completely absent for the Barents Sea. It is known that the most abundant cephalopods in the Arctic are Rossia palpebrosa and Gonatus fabricii. Their biomass and abundance have been assessed for the first time in the Barents Sea and adjacent waters. The maximum biomass of R. palpebrosa in the Barents Sea was 6.216–6.454 thousand tonnes with an abundance of 521.5 million specimens. Increased densities of biomass were annually registered in the north-eastern parts of the Barents Sea. The maximum biomass of G. fabricii in the Barents Sea was 24.797 thousand tonnes with an abundance of 1.705 billion specimens. The areas with increased density of biomass (higher than 100 kg km−2) and abundance (more than 10,000 specimens km−2) were concentrated in deep-water troughs in the marginal parts of the Barents Sea and in adjacent deep-water areas. The biomass and abundance of R. palpebrosa and G. fabricii in the Barents Sea were much lower than those of major taxa of invertebrates and fish and than those of cephalopods in other parts of the World Ocean. It has been suggested that the importance of cephalopods in the Arctic ecosystems, at least in terms of quantitative distribution, could be somewhat lower than in the Antarctic or the tropics. Despite the impact of ongoing warming of the Arctic on the distribution of cephalopods being described repeatedly already, no impact of the current year's climate on the studied species was found. The only exception was the abundance of R. palpebrosa, which correlated with the current year's climate conditions.


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