The structure of the mesoplankton community in the area of the continental slope of the St. Anna Trough (Kara Sea)

Abstract The values and direction of carbon dioxide flux in the area of the continental slope in the north of the Kara Sea (St. Anna Trough) are calculated based on field studies in 2020 within the Siberian Arctic Sea Ecosystems program. The existence of a stable frontal zone in this area has been confirmed, which is formed by an alongslope current and limits the northward spread of surface waters freshened by the continental runoff. The simultaneous analysis of the carbonate system in the upper sea layer and the CO2 concentration in the surface air layer shows the CO2 flux with a rate of 0.2 to 22 mmol/m2 day to be directed from the atmosphere into the water in the area of the outer shelf, which is affected by the river runoff, and in the area of the continental slope, which is beyond this effect. The highest rates of CO2 absorption by the sea surface layer are localized above the continental slope. Local processes in the area of the slope frontal zone determine the CO2 emission into the atmosphere with a rate of 0.34 mmol/m2 day.

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New data on the fauna and the biogeographic structure of the Hydrozoa, Scyphozoa, Staurozoa and Alcyonacea (Anthozoa) of the Kara Sea

Proceedings of the Zoological Institute RAS ◽

10.31610/trudyzin/2021.325.2.143 ◽

2021 ◽

Vol 325 (2) ◽

pp. 143-155

Author(s):

N.E. Zhuravleva

Keyword(s):

Cold Water ◽

Kara Sea ◽

Novaya Zemlya ◽

The North ◽

Anna Trough ◽

New Material ◽

Western Side ◽

Academy Of Sciences ◽

North Western ◽

Arctic Fauna

The paper considers the species composition of the fauna of several cnidarian groups of the Kara Sea. The author presents a list of species of the studied groups and indicates the types of habitat for each species. The analysis was based on the literature data, the collections of the Zoological Institute of the Russian Academy of Sciences and material collected in the Kara Sea during the expedition to the R/V Professor Multanovsky in 2019. In total, 87 species of Hydrozoa, 3 species of Scyphozoa, 4 species of Staurozoa, and 5 species of the order Alcyonacea from the class Anthozoa were recorded for the fauna of the Kara Sea, based on the new material obtained by the author and published literature data. The report presents the biogeographic structure of the discussed cnidarian groups. According to the types of biogeographic ranges, the fauna of the above-mentioned cnidarian groups in the Kara Sea mostly consists of representatives of the Boreal-Arctic type of habitat (63%), the Boreal and Amphiboreal biogeographic groups each containing 12% of the total number of described species, and the Panoceanic and Arctic groups together accounting for only 9% and 4% of the fauna of the Kara Sea. Two species new for the Kara Sea, Neoturris pileata (Forsskål, 1775) and Neoturris pileata (Forsskål, 1775), are described. Neoturris pileata is an element of the warm-water Atlantic fauna that penetrated into the Kara Sea with waters of Atlantic genesis. Nausithoe werneri is an element of the cold-water Arctic fauna that penetrated into the Novaya Zemlya Trough of the Kara Sea from the north-western side from the St. Anna Trough, which was open to the Polar Basin.

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Distribution of bacterioplankton with active metabolism in waters of the St. Anna Trough, Kara Sea, in autumn 2011

Oceanology ◽

10.1134/s0001437017010118 ◽

2017 ◽

Vol 57 (1) ◽

pp. 114-121 ◽

Cited By ~ 1

Author(s):

I. V. Mosharova ◽

S. A. Mosharov ◽

V. V. Ilinskiy

Keyword(s):

Kara Sea ◽

Active Metabolism ◽

Anna Trough

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Heat loss from the Atlantic water layer in the St. Anna Trough (northern Kara Sea): causes and consequences

Ocean Science Discussions ◽

10.5194/osd-11-543-2014 ◽

2014 ◽

Vol 11 (1) ◽

pp. 543-573 ◽

Cited By ~ 2

Author(s):

I. A. Dmitrenko ◽

S. A. Kirillov ◽

N. Serra ◽

N. V. Koldunov ◽

V. V. Ivanov ◽

...

Keyword(s):

Sea Ice ◽

Heat Loss ◽

Water Layer ◽

Atlantic Water ◽

Kara Sea ◽

The Arctic ◽

Model Simulations ◽

Eastern Flank ◽

Anna Trough ◽

Water Pathway

Abstract. A distinct, subsurface density front along the eastern St. Anna Trough in the northern Kara Sea is inferred from hydrographic observations in 1996 and 2008–2010. Direct velocity measurements show a persistent northward subsurface current (~ 20 cm s−1) along the St. Anna Trough eastern flank. This sheared flow, carrying the outflow from the Barents and Kara Seas to the Arctic Ocean, is also evident from shipboard observations as well as from geostrophic velocities and numerical model simulations. Although no clear evidence for the occurrence of shear instabilities could be obtained, we speculate that the enhanced vertical mixing along the St. Anna Trough eastern flank promoted by a vertical velocity shear favors the upward heat loss from the intermediate warm Atlantic water layer. The associated upward heat flux is inferred to 50–100 W m−2 using hydrographic data and model simulations. The zone of lowered sea ice thickness and concentration essentially marks the Atlantic water pathway in the St. Anna Trough and adjacent Nansen Basin continental margin from both sea-ice remote sensing observations and model simulations. In fact, the seaice shows a consistently delayed freeze-up onset during fall and a reduction in the seaice thickness during winter. This is consistent with our results on the enhanced Atlantic water heat loss along the Atlantic water pathway in the St. Anna Trough.1 1Dedicated to the memory of our colleague Klaus Hochheim who tragically lost his life in the Arctic expedition in September 2013

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Macrobenthos of the southern part of St. Anna trough and the adjacent Kara Sea shelf

Oceanology ◽

10.1134/s0001437015040098 ◽

2015 ◽

Vol 55 (4) ◽

pp. 614-622 ◽

Cited By ~ 2

Author(s):

S. V. Galkin ◽

A. A. Vedenin ◽

K. V. Minin ◽

A. V. Rogacheva ◽

T. N. Molodtsova ◽

...

Keyword(s):

Kara Sea ◽

Anna Trough

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Atlantic water flow into the Arctic Ocean through the St. Anna Trough in the northern Kara Sea

Journal of Geophysical Research Oceans ◽

10.1002/2015jc010804 ◽

2015 ◽

Vol 120 (7) ◽

pp. 5158-5178 ◽

Cited By ~ 17

Author(s):

Igor A. Dmitrenko ◽

Bert Rudels ◽

Sergey A. Kirillov ◽

Yevgeny O. Aksenov ◽

Vidar S. Lien ◽

...

Keyword(s):

Arctic Ocean ◽

Water Flow ◽

Atlantic Water ◽

Kara Sea ◽

The Arctic ◽

The Arctic Ocean ◽

Anna Trough

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Clay minerals as an indicator of the accumulation of the Upper Quaternary deposits in the St. Anna Trough (Kara Sea)

Oceanology ◽

10.1134/s0001437008010104 ◽

2008 ◽

Vol 48 (1) ◽

pp. 85-93 ◽

Cited By ~ 4

Author(s):

A. A. Krylov ◽

D. Weiel ◽

V. F. Sapega ◽

G. I. Ivanov ◽

R. Stein ◽

...

Keyword(s):

Clay Minerals ◽

Kara Sea ◽

Quaternary Deposits ◽

Anna Trough

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Late Weichselian deglacial history of the Svyataya (Saint) Anna Trough, northern Kara Sea, Arctic Russia

Marine Geology ◽

10.1016/s0025-3227(97)00096-0 ◽

1997 ◽

Vol 143 (1-4) ◽

pp. 169-188 ◽

Cited By ~ 84

Author(s):

Leonid Polyak ◽

Steven L. Forman ◽

Frances A. Herlihy ◽

Gennady Ivanov ◽

Pyotr Krinitsky

Keyword(s):

Kara Sea ◽

Anna Trough ◽

History Of ◽

Late Weichselian ◽

Arctic Russia

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Arsenic and mercury contamination in 31 cores taken in 1965, St. Anna Trough, Kara Sea, Arctic Ocean

Environmental Geology ◽

10.1007/s002540000194 ◽

2001 ◽

Vol 40 (4-5) ◽

pp. 528-542 ◽

Cited By ~ 9

Author(s):

F. R. Siegel ◽

Joseph H. Kravitz ◽

Jennifer J. Galasso

Keyword(s):

Arctic Ocean ◽

Kara Sea ◽

Mercury Contamination ◽

Anna Trough

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Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequences

Ocean Science ◽

10.5194/os-10-719-2014 ◽

2014 ◽

Vol 10 (4) ◽

pp. 719-730 ◽

Cited By ~ 17

Author(s):

I. A. Dmitrenko ◽

S. A. Kirillov ◽

N. Serra ◽

N. V. Koldunov ◽

V. V. Ivanov ◽

...

Keyword(s):

Sea Ice ◽

Heat Loss ◽

Water Layer ◽

Atlantic Water ◽

Kara Sea ◽

Ice Thickness ◽

Sea Ice Thickness ◽

Model Simulations ◽

Anna Trough ◽

Water Pathway

Abstract. A distinct, subsurface density front along the eastern St. Anna Trough in the northern Kara Sea is inferred from hydrographic observations in 1996 and 2008–2010. Direct velocity measurements show a persistent northward subsurface current (~ 18 cm s−1) along the St. Anna Trough eastern flank. This sheared flow, carrying the outflow from the Barents and Kara seas to the Arctic Ocean, is also evident from shipboard observations as well as from geostrophic velocities and numerical model simulations. Although we cannot substantiate our conclusions by direct observation-based estimates of mixing rates in the area, we hypothesize that the enhanced vertical mixing along the St. Anna Trough eastern flank favors the upward heat loss from the intermediate warm Atlantic water layer. Modeling results support this hypothesis. The upward heat flux inferred from hydrographic data and model simulations is of O(30–100) W m−2. The region of lowered sea ice thickness and concentration seen both in sea ice remote sensing observations and model simulations marks the Atlantic water pathway in the St. Anna Trough and adjacent Nansen Basin continental margin. In fact, the sea ice shows a delayed freeze-up onset during fall and a reduction in the sea ice thickness during winter. This is consistent with our results on the enhanced Atlantic water heat loss along the Atlantic water pathway in the St. Anna Trough.

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