scholarly journals Dynamics of the Spatial Chlorophyll-A Distribution at the Polar Front in the Marginal Ice Zone of the Barents Sea during Spring

Water ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 101
Author(s):  
Pavel R. Makarevich ◽  
Veronika V. Vodopianova ◽  
Aleksandra S. Bulavina
Keyword(s):  
Species Composition ◽  
Sea Ice ◽  
Chlorophyll A ◽  
Phytoplankton Community ◽  
Barents Sea ◽  
Sea Water ◽  
Polar Front ◽  
Ice Melting ◽  
The Barents Sea ◽  
Ice Edge

Effects of the sea-ice edge and the Polar Frontal Zone on the distribution of chlorophyll-a levels in the pelagic were investigated during multi-year observations in insufficiently studied and rarely navigable regions of the Barents Sea. Samples were collected at 52 sampling stations combined into 11 oceanographic transects over a Barents Sea water area north of the latitude 75° N during spring 2016, 2018, and 2019. The species composition, abundance and biomass of the phytoplankton community, chlorophyll-a concentrations, hydrological and hydrochemical parameters were analyzed. The annual phytoplankton evolution phase, defined as an early-spring one, was determined throughout the transects. The species composition of the phytoplankton community and low chlorophyll-a levels suggested no phytoplankton blooming in April 2016 and 2019. Not yet started sea-ice melting prevented sympagic (sea-ice-associated) algae from being released into the seawater. In May 2018, ice melting began in the eastern Barents Sea and elevated chlorophyll-a levels were recorded near the ice edge. Chlorophyll-a concentrations substantially differed in waters of different genesis, especially in areas influenced by the Polar Front. The Polar Front separated the more productive Arctic waters with a chlorophyll-a concentration of 1–5 mg/m3 on average from the Atlantic waters where the chlorophyll-a content was an order of magnitude lower.

scholarly journals Climate-driven benthic invertebrate activity and biogeochemical functioning across the Barents Sea polar front

2020 ◽  
Vol 378 (2181) ◽  
pp. 20190365 ◽  
Author(s):  
Martin Solan ◽  
Ellie R. Ward ◽  
Christina L. Wood ◽  
Adam J. Reed ◽  
Laura J. Grange ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ecosystem Functioning ◽  
Barents Sea ◽  
Benthic Invertebrate ◽  
Polar Front ◽  
The Arctic ◽  
Nutrient Concentrations ◽  
Sea Ice Extent ◽  
Biological Communities ◽  
The Barents Sea

Arctic marine ecosystems are undergoing rapid correction in response to multiple expressions of climate change, but the consequences of altered biodiversity for the sequestration, transformation and storage of nutrients are poorly constrained. Here, we determine the bioturbation activity of sediment-dwelling invertebrate communities over two consecutive summers that contrasted in sea-ice extent along a transect intersecting the polar front. We find a clear separation in community composition at the polar front that marks a transition in the type and amount of bioturbation activity, and associated nutrient concentrations, sufficient to distinguish a southern high from a northern low. While patterns in community structure reflect proximity to arctic versus boreal conditions, our observations strongly suggest that faunal activity is moderated by seasonal variations in sea ice extent that influence food supply to the benthos. Our observations help visualize how a climate-driven reorganization of the Barents Sea benthic ecosystem may be expressed, and emphasize the rapidity with which an entire region could experience a functional transformation. As strong benthic-pelagic coupling is typical across most parts of the Arctic shelf, the response of these ecosystems to a changing climate will have important ramifications for ecosystem functioning and the trophic structure of the entire food web. This article is part of the theme issue ‘The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.

scholarly journals The Barents Sea frontal zones and water masses variability (1980–2011)

Ocean Science ◽  
2016 ◽  
Vol 12 (1) ◽  
pp. 169-184 ◽  
Author(s):  
L. Oziel ◽  
J. Sirven ◽  
J.-C. Gascard
Keyword(s):  
Interannual Variability ◽  
Barents Sea ◽  
Sea Water ◽  
Atlantic Water ◽  
Polar Front ◽  
Water Masses ◽  
The Arctic ◽  
Arctic Water ◽  
The Barents Sea ◽  
Frontal Zones

Abstract. The polar front separates the warm and saline Atlantic Water entering the southern Barents Sea from the cold and fresh Arctic Water located in the north. These water masses can mix together (mainly in the center of the Barents Sea), be cooled by the atmosphere and receive salt because of brine release; these processes generate dense water in winter, which then cascades into the Arctic Ocean to form the Arctic Intermediate Water. To study the interannual variability and evolution of the frontal zones and the corresponding variations of the water masses, we have merged data from the International Council for the Exploration of the Sea and the Arctic and Antarctic Research Institute and have built a new database, which covers the 1980–2011 period. The summer data were interpolated on a regular grid. A probability density function is used to show that the polar front splits into two branches east of 32° E where the topographic constraint weakens. Two fronts can then be identified: the Northern Front is associated with strong salinity gradients and the Southern Front with temperature gradients. Both fronts enclose the denser Barents Sea Water. The interannual variability of the water masses is apparent in the observed data and is linked to that of the ice cover. The frontal zones variability is found by using data from a general circulation model. The link with the atmospheric variability, represented here by the Arctic Oscillation, is not clear. However, model results suggest that such a link could be validated if winter data were taken into account. A strong trend appears: the Atlantic Water (Arctic Water) occupies a larger (smaller) volume of the Barents Sea. This trend amplifies during the last decade and the model study suggests that this could be accompanied by a northwards displacement of the Southern Front in the eastern part of the Barents Sea. The results are less clear for the Northern Front. The observations show that the volume of the Barents Sea Water remains nearly unchanged, which suggests a northwards shift of the Northern Front to compensate for the northward shift of the Southern Front. Lastly, we noticed that the seasonal variability of the position of the front is small.

scholarly journals SOME RESULTS OF ARCTIC PLANKTON COMMUNITIES STUDY (THE BARENTS SEA)

2020 ◽  
Vol 11 (4) ◽  
pp. 44-84
Author(s):  
E.I. Druzhkova ◽  
◽  
I.V. Berchenko ◽  
A.V. Vaschenko ◽  
M.P. Venger ◽  
...  
Keyword(s):  
Barents Sea ◽  
Water Area ◽  
Polar Front ◽  
Polar Night ◽  
Edge Zone ◽  
The Barents Sea ◽  
Different Seasons ◽  
Ice Edge ◽  
Zooplankton Communities ◽  
Plankton Communities

This paper presents some research results of the plankton laboratory MMBI RAS over the past 5 years. One of the main directions was the study of the structure of zooplankton communities and an assessment of their productivity off the coast of the Kola Peninsula and in the coastal waters of the Svalbard archipelago.Analysis of the vast perennial material revealed the main features of the spatial distribution of phytoplankton in the water area of the Pechora Sea. In the ice edge zone for nano-, micro-and zooplankton, the presence of ice edge effect in different seasons of the year is shown. It has been shown that in the Barents Sea, the Polar Front is not the boundary between various pelagic phytocenoses. During the polar night, virio-, bacterio-, phyto-and zooplankton were studied. When studyingthe deep-sea Barents Sea shelf, an autochthonous community of microalgae was found, the lower distribution limit of which is 300 m isobath.

Sea Ice Distribution in the Barents Sea

2016 ◽  
Author(s):  
Sindre M. Fritzner ◽  
Trond Sagerup
Keyword(s):  
Sea Ice ◽  
Normal Distribution ◽  
Barents Sea ◽  
Extreme Value Distribution ◽  
Extreme Value ◽  
Distribution Functions ◽  
Value Distribution ◽  
The Barents Sea ◽  
Ice Edge ◽  
Sea Ice Edge

This paper provides a statistical description of the sea ice occurrence in the Barents Sea, using yearly maximum sea ice data for the last 36 years from the European Centre for Medium-Range Weather Forecasts (ECMWF). A set of four distribution functions have been estimated with the maximum likelihood method. The distribution functions used were Extreme Value distribution, Gumbel distribution, Normal distribution and kernel density estimation. The normal distribution was found to fit the data best and provide the most likely result. Our results verify dependency of the North Atlantic current on the sea ice edge. Warm water northwards prevents the ice from extending south; this makes the extreme value distribution unlikely since this will prevent long tailed distributions. The results for sea ice occurrence are compared to the boundaries given in the proposed revision to NORSOK N-003. These boundaries were found to be too simplistic and not necessarily conservative. Here we have proposed new and more accurate boundaries for the sea ice occurrence. We have found trends indicating northwards movement of the sea ice edge in the Norwegian Sea and eastern parts of the Barents Sea. These trends are mostly due to less ice in the last ten years and not trends for the whole period. In the south-western parts of the Barents Sea where oil and gas operations are imminent no trends have been discovered. The lack of trend is related to the islands in the western Barents Sea.

scholarly journals The Barents Sea polar front and water masses variability (1980–2011)

2015 ◽  
Vol 12 (2) ◽  
pp. 449-492 ◽  
Author(s):  
L. Oziel ◽  
J. Sirven ◽  
J.-C. Gascard
Keyword(s):  
Interannual Variability ◽  
General Circulation ◽  
Barents Sea ◽  
Sea Water ◽  
Circulation Model ◽  
Atlantic Water ◽  
Polar Front ◽  
Water Masses ◽  
The Arctic ◽  
The Barents Sea

Abstract. The polar front separates the warm and saline Atlantic Waters encountered in the western part of the Barents Sea from the cold and fresh Arctic Waters situated in the northern part. These water masses can mix together, mainly in the eastern part of the Barents Sea, generating dense waters in winter which can cascade into the Arctic Ocean to form the Artic Intermediate Waters. To study the interannual variability and evolution of these water masses and the fronts, we have merged data from the International Council for the Exploration of the Sea and the Arctic and Antarctic Research Institute and have built a new database which covers the period 1980–2011. The summer data is interpolated on a regular grid and a "Probability Density Function" method is used to show that the polar front splits into two branches east of 32° E where the topographic constraint weakens. Two fronts can then be defined: the "Northern Polar Front" is associated with strong salinity gradients and the "Southern Polar Front" with temperature gradients. They enclose the dense Barents Sea Water. The interannual variability of the water masses is apparent in the observed data and is linked to that of the ice cover. In contrast, the link with the Arctic Oscillation is not clear. However, results from a general circulation model suggest that such a link could be found if winter data were taken into account. A strong trend, which amplifies during the last decade, is also found: the Atlantic Water occupies a larger volume of the Barents Sea. This "Atlantification" could be accompanied by a northwards displacement of the southern polar front in the eastern part of the Barents Sea (which is suggested by a model based study) and a decrease of the volume occupied by the Arctic Waters.

scholarly journals Thickness and density of snow-covered sea ice and hydrostatic equilibrium assumption from in situ measurements in Fram Strait, the Barents Sea and the Svalbard coast

2011 ◽  
Vol 52 (57) ◽  
pp. 261-270 ◽  
Author(s):  
Sanja Forsström ◽  
Sebastian Gerland ◽  
Christina A. Pedersen
Keyword(s):  
Sea Ice ◽  
Barents Sea ◽  
Sea Water ◽  
Hydrostatic Equilibrium ◽  
Ice Thickness ◽  
Fram Strait ◽  
Sea Ice Thickness ◽  
The Barents Sea ◽  
Snow And Ice

AbstractModern satellite measurements of sea-ice thickness are based on altimeter measurements of the difference in elevation between the snow or ice surface and the local sea surface. For retrieval of sea-ice thickness, it is assumed that the ice is in hydrostatic equilibrium, and that the snow load on the ice and the density of the sea ice and sea water are known. This study presents data from in situ sea-ice thickness drillings and snow and ice density measurements from Fram Strait, the Barents Sea and the Svalbard coast, in the European Arctic. the error in the altimetry ice thickness products is assessed based on the spatial variability of snow and ice density and snow thickness data. Ice thickness uncertainty related to snow depth was found to be ∼40 cm (radar altimeter) and ∼90 cm (laser altimeter), while uncertainty related to ice density is 25 cm for both techniques. the assumption of hydrostatic equilibrium at the scales of the measurements (10–100 m) was found to hold better in the case of level landfast ice near Svalbard than for Fram Strait drift ice, which consists of mixed ice types, where the deviation between the calculated and measured ice thicknesses was on average ∼0.5 m.

Sign in / Sign up

Export Citation Format

Share Document