scholarly journals Trends in the intensity of dense water cascading from the Arctic shelves due to ice cover reduction in the Arctic seas

2021 ◽  
Vol 67 (4) ◽  
pp. 318-327
Author(s):  
F. K. Tuzov
Keyword(s):  
Arctic Ocean ◽  
Barents Sea ◽  
Beaufort Sea ◽  
Ice Cover ◽  
The Arctic ◽  
Arctic Seas ◽  
Dense Water ◽  
The Barents Sea ◽  
The Arctic Ocean ◽  
Shelf Seas

The article discusses the possible relationship between changes in the ice cover area of the shelf seas of the Arctic Ocean and the intensity of dense water cascading, based on calculation data obtained with the NEMO model for the period 1986–2010, with the findings issued at 5-day intervals and a spatial resolution of 1/10°. The cascading cases were calculated using an innovative method developed by the author. The work is based on the assumption that as the ice cover in the seas retreats, the formation of cooled dense water masses is intensified, which submerge and flow down the slope from the shelf to great depths. Thus, in the Arctic shelf seas, the mechanism of water densification due to cooling is added to the mechanism of water densification during ice formation, or, replaces it for certain regions. It was found that in the Barents Sea, the Laptev Sea and the Beaufort Sea, a decrease in the ice cover area causes an increase in the number of cases of cascading. However, in most of the Arctic seas, as the area of ice cover decreases, the number of cases of cascading also decreases. As a consequence, for the whole Arctic shelf area, the number of cases of cascading also decreases with decreasing ice cover. It is shown that in the Beaufort Sea the maximum number of cascading cases was observed in the winter period of 2007–2008, which was preceded by the summer minimum of the ice cover area in the Arctic Ocean. In the Barents Sea after 2000, a situation has been observed where the ice area has been decreasing to zero values, whereas the number of cascading cases has for some time (1 month approximately) remained close to high winter values. This possibly means that the cooling and densification of the waters in ice-free areas occurs due to thermal convection. Based on the calculation of the number of cases of cascading, it can be argued that the intensification of cascading due to a reduction in the ice cover is a feature of individual seas of the Arctic Ocean, those in which there is no excessive freshening of the upper water layer due to ice melting.

Characteristics of the Russian shelf seas in the Arctic Ocean regarding the content of heavy minerals in surface sediments: new data

2021 ◽  
Author(s):  
Elena Popova
Keyword(s):  
Arctic Ocean ◽  
Environmental Science ◽  
Barents Sea ◽  
Source Rocks ◽  
Heavy Minerals ◽  
The Arctic ◽  
Arctic Seas ◽  
Riverine Input ◽  
The Arctic Ocean ◽  
Shelf Seas

<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>

Increasing Multiyear Sea Ice Loss in the Beaufort Sea: A New Export Pathway for the Diminishing Multiyear Ice Cover of the Arctic Ocean

2021 ◽  
Author(s):  
David Gareth Babb ◽  
Ryan J. Galley ◽  
Stephen E. L. Howell ◽  
Jack Christopher Landy ◽  
Julienne Christine Stroeve ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Beaufort Sea ◽  
Ice Cover ◽  
The Arctic ◽  
Export Pathway ◽  
The Arctic Ocean ◽  
Multiyear Ice

Regularities and features of ice conditions of the Barents Sea in the second half of XX – early XXI century

2021 ◽  
pp. 179-194
Author(s):  
I.O. Dumanskaya ◽  
Keyword(s):  
Barents Sea ◽  
Ice Cover ◽  
Heat Fluxes ◽  
The Arctic ◽  
Cycle Period ◽  
Arctic Seas ◽  
Sea Ice Extent ◽  
The Barents Sea ◽  
Western Border ◽  
Quantitative Changes

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.

scholarly journals Spatial Distribution of Atmospheric Aerosol Physicochemical Characteristics in the Russian Sector of the Arctic Ocean

Atmosphere ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1170
Author(s):  
Sergey Sakerin ◽  
Dmitry Kabanov ◽  
Valery Makarov ◽  
Viktor Pol’kin ◽  
Svetlana Popova ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Chemical Composition ◽  
Arctic Ocean ◽  
Black Carbon ◽  
Forest Fires ◽  
Barents Sea ◽  
The Arctic ◽  
The North ◽  
The Barents Sea ◽  
The Arctic Ocean

The results from studies of aerosol in the Arctic atmosphere are presented: the aerosol optical depth (AOD), the concentrations of aerosol and black carbon, as well as the chemical composition of the aerosol. The average aerosol characteristics, measured during nine expeditions (2007–2018) in the Eurasian sector of the Arctic Ocean, had been 0.068 for AOD (0.5 µm); 2.95 cm−3 for particle number concentrations; 32.1 ng/m3 for black carbon mass concentrations. Approximately two–fold decrease of the average characteristics in the eastern direction (from the Barents Sea to Chukchi Sea) is revealed in aerosol spatial distribution. The average aerosol characteristics over the Barents Sea decrease in the northern direction: black carbon concentrations by a factor of 1.5; particle concentrations by a factor of 3.7. These features of the spatial distribution are caused mainly by changes in the content of fine aerosol, namely: by outflows of smokes from forest fires and anthropogenic aerosol. We considered separately the measurements of aerosol characteristics during two expeditions in 2019: in the north of the Barents Sea (April) and along the Northern Sea Route (July–September). In the second expedition the average aerosol characteristics turned out to be larger than multiyear values: AOD reached 0.36, particle concentration up to 8.6 cm−3, and black carbon concentration up to 179 ng/m3. The increased aerosol content was affected by frequent outflows of smoke from forest fires. The main (99%) contribution to the elemental composition of aerosol in the study regions was due to Ca, K, Fe, Zn, Br, Ni, Cu, Mn, and Sr. The spatial distribution of the chemical composition of aerosols was analogous to that of microphysical characteristics. The lowest concentrations of organic and elemental carbon (OC, EC) and of most elements are observed in April in the north of the Barents Sea, and the maximal concentrations in Far East seas and in the south of the Barents Sea. The average contents of carbon in aerosol over seas of the Asian sector of the Arctic Ocean are OC = 629 ng/m3, EC = 47 ng/m3.

A satellite-based Lagrangian perspective on Atlantic Water fractionation in the Nordic Seas

2020 ◽  
Author(s):  
Léon Chafik ◽  
Sara Broomé
Keyword(s):  
Arctic Ocean ◽  
Barents Sea ◽  
Bottom Topography ◽  
Atlantic Water ◽  
The Arctic ◽  
Fram Strait ◽  
Nordic Seas ◽  
The Barents Sea ◽  
The Arctic Ocean ◽  
Outer Branch

<p>The Arctic Ocean has been receiving more of the warm and saline Atlantic Water in the past decades. This water mass enters the Arctic Ocean via two Arctic gateways: the Barents Sea Opening and the Fram Strait. Here, we focus on the fractionation of Atlantic Water at these two gateways using a Lagrangian approach based on satellite-derived geostrophic velocities. Simulated particles are released at 70N at the inner and outer branch of the North Atlantic current system in the Nordic Seas. The trajectories toward the Fram Strait and Barents Sea Opening are found to be largely steered by the bottom topography and there is an indication of an anti-phase relationship in the number of particles reaching the gateways. There is, however, a significant cross-over of particles from the outer branch to the inner branch and into the Barents Sea, which is found to be related to high eddy kinetic energy between the branches. This cross-over may be important for Arctic climate variability.</p>

scholarly journals On available energy in the ocean and its application to the Barents Sea

2007 ◽  
Vol 4 (6) ◽  
pp. 897-931
Author(s):  
R. C. Levine ◽  
D. J. Webb
Keyword(s):  
Arctic Ocean ◽  
Barents Sea ◽  
Exact Expression ◽  
The Arctic ◽  
Global Ocean ◽  
Boundary Current ◽  
Available Energy ◽  
The Barents Sea ◽  
The Arctic Ocean ◽  
Definition Of

Abstract. Following meteorological practice the definition of available potential energy in the ocean is conventionally defined in terms of the properties of the global ocean. However there is also a requirement for a localised definition, for example the energy released when shelf water cascades down a continental shelf in the Arctic and enters a boundary current. In this note we start from first principals to obtain an exact expression for the available energy (AE) in such a situation. We show that the available energy depends on enstrophy and gravity. We also show that it is exactly equal to the work done by the pressure gradient and by buoyancy. The results are used to investigate the distribution of AE in the Barents Sea and surrounding regions relative to the interior of the Arctic Ocean. We find that water entering the Barents Sea from the Atlantic already has a high AE, that it is increased by cooling but that much of the increase is lost overcoming turbulence during the passage through the region to the Arctic Ocean. However on entering the Arctic enough available energy remains to drive a significant current around the margin of the ocean. The core of raised available energy also acts as a tracer which can be followed along the continental slope beyond the dateline.

Transformation of Atlantic Water in the Barents Sea in winter: overview of “Transarctika-2019” cruise results

2020 ◽  
Author(s):  
Vladimir Ivanov ◽  
Ivan Frolov ◽  
Kirill Filchuk
Keyword(s):  
Characteristic Feature ◽  
Sea Ice ◽  
Arctic Ocean ◽  
Water Column ◽  
Barents Sea ◽  
Atlantic Water ◽  
The Arctic ◽  
The Barents Sea ◽  
Open Sea ◽  
The Arctic Ocean

<p>In the recent few years the topic of accelerated sea ice loss, and related changes in the vertical structure of water masses in the East-Atlantic sector of the Arctic Ocean, including the Barents Sea and the western part of the Nansen Basin, has been in the foci of multiple studies. This region even earned the name the “Arctic warming hotspot”, due to the extreme retreat of sea ice and clear signs of change in the vertical hydrographic structure from the Arctic type to the sub-Arctic one. A gradual increase in temperature and salinity in this area has been observed since the mid-2000s. This trend is hypothetically associated with a general decrease in the volume of sea ice in the Arctic Ocean, which leads to a decrease of ice import in the Barents Sea, salinization, weakening of density stratification, intensification of vertical mixing and an increase of heat and salt fluxes from the deep to the upper mixed layer. The result of such changes is a further reduction of sea ice, i.e. implementation of positive feedback, which is conventionally refereed as the “atlantification. Due to the fact that the Barents Sea is a relatively shallow basin, the process of atlantification might develop here much faster than in the deep Nansen Basin. Thus, theoretically, the hydrographic regime in the northern part of the Barents Sea may rapidly transform to a “Nordic Seas – wise”, a characteristic feature of which is the year-round absence of the ice cover with debatable consequences for the climate and ecosystem of the region and adjacent land areas. Due to the obvious reasons, historical observations in the Barents Sea mostly cover the summer season. Here we present a rare oceanographic data, collected during the late winter - early spring in 2019. Measurements were occupied at four sequential oceanographic surveys from the boundary between the Norwegian Sea and the Barents Sea – the so called Barents Sea opening to the boundary between the Barents Sea and the Kara Sea. Completed hydrological sections allowed us to estimate the contribution of the winter processes in the Atlantic Water transformation at the end of the winter season. Characteristic feature of the observed transformation is the homogenization of the near-to-bottom part of the water column with remaining stratification in the upper part. A probable explanation of such changes is the dominance of shelf convection and cascading of dense water over the open sea convection. In this case, complete homogenization of the water column does not occur, since convection in the open sea is impeded by salinity and density stratification, which is maintained by melting of the imported sea ice in the relatively warm water. The study was supported by RFBR grant # 18-05-60083.</p>

scholarly journals New records of molluscs of the families Eulimidae and Pyramidellidae (Gastropoda) from the Barents Sea and adjacent Polar Basin

2017 ◽  
Vol 27 (2) ◽  
pp. 59-63
Author(s):  
Ivan O. Nekhaev
Keyword(s):  
Arctic Ocean ◽  
Coastal Waters ◽  
Barents Sea ◽  
New Records ◽  
The Arctic ◽  
Gastropod Species ◽  
The Barents Sea ◽  
New Findings ◽  
The Arctic Ocean ◽  
First Time

New findings of four gastropod species: Melanella laurae, Hemiaclis ventrosa (family Eulimidae), Chrysallida sublustris and Odostomia acuta (family Pyramidellidae) are described. O. acuta was previously confused by Russian authors with H. ventrosa, distribution of both species in the Barents Sea is limited to the coastal waters of Finmark and Murman. M. laurae and C. sublustris were found for the first time in the adjacent to the Barents Sea parts of the Arctic Ocean.

Dimethylsulfide model calibration in the Barents Sea using a genetic algorithm and neural network

2016 ◽  
Vol 13 (2) ◽  
pp. 413 ◽  
Author(s):  
Bo Qu ◽  
Albert J. Gabric ◽  
Meifang Zeng ◽  
Zhifeng Lu
Keyword(s):  
Neural Network ◽  
Genetic Algorithm ◽  
Arctic Ocean ◽  
Barents Sea ◽  
Sulfate Aerosol ◽  
The Arctic ◽  
Biogeochemical Model ◽  
The Barents Sea ◽  
The Arctic Ocean ◽  
Aerosol Emissions

Environmental context Future changes in marine biogenic aerosol emissions in Arctic seas are likely to affect the radiative budget of the region. Here we employ a calibrated biogeochemical model to simulate change in sulfate aerosol emissions in the Barents Sea, and find strong increases occur by the late 21st century. If replicated across the Arctic Ocean, such increases in sulfate aerosol loading to the Arctic atmosphere may decrease the rate of warming at polar latitudes. Abstract Global warming of climate is connected to ecosystem change, especially in the polar oceans. Biogenic emissions of dimethylsulfide (DMS) are the main biogenic source of sulfate aerosols to the marine atmosphere and may change in the Arctic, where warming is currently very rapid. Here, we simulate DMS distribution and sea-to-air flux in the Barents Sea (30–40°E and 70–80°N) for the period 2003–05. A genetic algorithm is used to calibrate the key parameters in the DMS model. We use MODIS satellite chlorophyll-a data and regional DMS field data to calibrate the model. Owing to limited DMS observations in the Arctic Ocean, multiple data sources were used and compared. A back-propagation neural network is used for predicting regional DMS based on previous history time series. Parameter sensitivity analysis is done based on DMS flux output. Global climate model forcings for 1×CO2 to 3×CO2 conditions are used to force the biogeochemical model under future climate warming (c. 2080). The simulation results show that under tripled CO2, DMS flux would increase 168 to 279% from autumn through winter and would increase 112% during ice melting season. DMS flux would increase much more in ice-melt-affected water. The increased DMS flux under 3×CO2 indicates that regional warming could slow owing to the emission of DMS in the Arctic, if the increase in emissions of anthropogenic greenhouse gases is controlled.

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