Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequences
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<sup>−1</sup>) along the St. A...
| Main Authors: | , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2014-08-01
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| Series: | Ocean Science |
| Online Access: | http://www.ocean-sci.net/10/719/2014/os-10-719-2014.pdf |
| _version_ | 1828879378546688000 |
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| author | I. A. Dmitrenko S. A. Kirillov N. Serra N. V. Koldunov V. V. Ivanov U. Schauer I. V. Polyakov D. Barber M. Janout V. S. Lien M. Makhotin Y. Aksenov |
| author_facet | I. A. Dmitrenko S. A. Kirillov N. Serra N. V. Koldunov V. V. Ivanov U. Schauer I. V. Polyakov D. Barber M. Janout V. S. Lien M. Makhotin Y. Aksenov |
| author_sort | I. A. Dmitrenko |
| collection | DOAJ |
| description | 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<sup>−1</sup>) 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 <i>O</i>(30–100) W m<sup>−2</sup>. 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. |
| first_indexed | 2024-12-13T09:27:05Z |
| format | Article |
| id | doaj.art-77f217797f91471f8fc36b08e2976b61 |
| institution | Directory Open Access Journal |
| issn | 1812-0784 1812-0792 |
| language | English |
| last_indexed | 2024-12-13T09:27:05Z |
| publishDate | 2014-08-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Ocean Science |
| spelling | doaj.art-77f217797f91471f8fc36b08e2976b612022-12-21T23:52:36ZengCopernicus PublicationsOcean Science1812-07841812-07922014-08-0110471973010.5194/os-10-719-2014Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequencesI. A. Dmitrenko0S. A. Kirillov1N. Serra2N. V. Koldunov3V. V. Ivanov4U. Schauer5I. V. Polyakov6D. Barber7M. Janout8V. S. Lien9M. Makhotin10Y. Aksenov11Centre for Earth Observation Science, University of Manitoba, Winnipeg, CanadaCentre for Earth Observation Science, University of Manitoba, Winnipeg, CanadaInstitute of Oceanography, University of Hamburg, Hamburg, GermanyInstitute of Oceanography, University of Hamburg, Hamburg, GermanyArctic and Antarctic Research Institute, St. Petersburg, RussiaAlfred Wegener Institute for Polar and Marine Research, Bremerhaven, GermanyInternational Arctic Research Center, University of Alaska Fairbanks, Fairbanks, AK, USACentre for Earth Observation Science, University of Manitoba, Winnipeg, CanadaAlfred Wegener Institute for Polar and Marine Research, Bremerhaven, GermanyInstitute of Marine Research, Bergen, NorwayArctic and Antarctic Research Institute, St. Petersburg, RussiaNational Oceanography Centre Southampton, Southampton, UK<br><br> Dedicated to the memory of our colleague Klaus Hochheim, who tragically lost his life in the Arctic expedition in September 2013A 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<sup>−1</sup>) 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 <i>O</i>(30–100) W m<sup>−2</sup>. 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.http://www.ocean-sci.net/10/719/2014/os-10-719-2014.pdf |
| spellingShingle | I. A. Dmitrenko S. A. Kirillov N. Serra N. V. Koldunov V. V. Ivanov U. Schauer I. V. Polyakov D. Barber M. Janout V. S. Lien M. Makhotin Y. Aksenov Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequences Ocean Science |
| title | Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequences |
| title_full | Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequences |
| title_fullStr | Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequences |
| title_full_unstemmed | Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequences |
| title_short | Heat loss from the Atlantic water layer in the northern Kara Sea: causes and consequences |
| title_sort | heat loss from the atlantic water layer in the northern kara sea causes and consequences |
| url | http://www.ocean-sci.net/10/719/2014/os-10-719-2014.pdf |
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