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- Björk, Göran, 1956, et al.
(author)
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Flow of Canadian Basin Deep Water in the Western Eurasian Basin of the Arctic Ocean
- 2010
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In: Deep Sea Research. - : Elsevier BV. - 0967-0637 .- 1879-0119. ; 57:4, s. 577-586
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Journal article (peer-reviewed)abstract
- The LOMROG 2007 expedition targeted the previously unexplored southern part of the Lomonosov Ridge north of Greenland together with a section from the Morris Jesup Rise to Gakkel Ridge. The oceanographic data shows that Canadian Basin Deep Water (CBDW) passes the Lomonosov Ridge in the area of the Intra Basin close to the North Pole and then continues along the ridge towards Greenland and further along its northernmost continental slope. The CBDW is clearly evident as a salinity maximum and oxygen minimum at a depth of about 2000 m. The cross slope sections at the Amundsen Basin side of the Lomonosov Ridge and further south at the Morris Jesup Rise show a sharp frontal structure higher up in the water column between Makarov Basin water and Amundsen Basin water. The frontal structure continues upward into the Atlantic Water up to a depth of about 300 m. The observed water mass division at levels well above the ridge crest indicates a strong topographic steering of the flow and that different water masses tend to pass the ridge guided by ridge-crossing isobaths at local topographic heights and depressions. A rough scaling analysis shows that the extremely steep and sharply turning bathymetry of the Morris Jesup Rise may force the boundary current to separate and generate deep eddies.
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2. |
- Linders, Johanna, et al.
(author)
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On the nature and origin of water masses in Herald Canyon, Chukchi Sea: Synoptic surveys in summer 2004, 2008, and 2009
- 2017
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In: Progress in Oceanography. - : Elsevier BV. - 0079-6611. ; 159, s. 99-114
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Journal article (peer-reviewed)abstract
- Hydrographic and velocity data from three high-resolution shipboard surveys of Herald Canyon in the northwest Chukchi Sea, in 2004, 2008, and 2009, are used to investigate the water masses in the canyon and their possible source regions. Both summer and winter Pacific waters were observed in varying amounts in the different years, although in general the summer waters resided on the eastern side of the canyon while the winter waters were located on the western flank. The predominant summer water was Bering summer water, although some Alaskan coastal water resided in the canyon in the two later years likely due to wind forcing. Both newly ventilated and remnant winter waters were found in the canyon, but the amount lessened in each successive survey. Using mooring data from Bering Strait it is shown that a large amount of Bering summer water in the western channel of the strait follows a relatively direct route into Herald Canyon during the summer months, with an estimated advective speed of 10–20 cm/s. However, while the winter water observed in 2004 was consistent with a Bering Strait source (with a slower advective speed of 5–8 cm/s), the dense water in the canyon during 2008 and 2009 was more in line with a northern source. This is consistent with sections to the west of the canyon and with previously reported measurements implying winter water formation on the East Siberian shelf. Large-scale wind patterns and polynya activity on the shelf are also investigated. It was found that the former appears to impact more strongly the presence of dense water in Herald Canyon. © 2017 Elsevier Ltd
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3. |
- Linders, Johanna, et al.
(author)
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The melt-freeze cycle of the Arctic Ocean ice cover and its dependence on ocean stratification
- 2013
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In: Journal of Geophysical Research-Oceans. - : American Geophysical Union (AGU). - 2169-9275 .- 2169-9291. ; 118:11, s. 5963-5976
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Journal article (peer-reviewed)abstract
- A time-dependent, 1-D coupled ice-ocean model is used to quantify the impact of ocean stratification on the Arctic ice cover. The model results show that the ice growth during winter equals the ice melt in summer for areas with a well-developed cold halocline layer (CHL), provided that the initial ice thickness is around 3 m, while thinner initial ice thickness results in net growth. Areas with weak salt stratification can have a negative annual thickness change irrespective of the initial ice thickness and are thus dependent on ice import in order to remain ice covered. The model results also show that ocean stratification is mostly important for ice-thickness development during the growing season. Areas with weak stratification have an ocean heat flux up to 8 W m(-2) reaching the ice during the growing season, while areas with a CHL have an average of about 0.7 W m(-2). In the extreme area, north of Svalbard, the ocean heat fluxes are typically around 25 W m(-2) but can be up to 400 W m(-2) during the initial adjustment, when the warm Atlantic water has direct contact with the ice. A general outcome of the study is that, depending on ocean stratification, the ice cover of Arctic Ocean can be divided into one part with net ice growth (the major part) and another part with net ice melt (mainly in the Nansen Basin).
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