• Journal of the korean society of oceanography
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• v.33 no.1-2
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• pp.1-7
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• 1998

In the western Weddell Sea, winter mixed layer is characterized by near-freezing temperature and higher salinity due to brine injection through sea-ice formation. This layer becomes Winter Water being capped by warmer and less saline Antarctic Surface Water during the sea-ice melt-ing season. In this study, Winter Water was preliminarily identified by the oxygen isotopic com-positions. The ${\delta}^{18}$O values of Winter Water show the progressively increasing trend from south to north in the study area. It presumably reflects the enhanced mixing with Antarctic Surface Water due to the extent of influence by low S'"0 value of sea-ice/glacier meltwater. Correlations between salinity and 6'"0 values of seawater can be used to more generally characterize Winter Water with a view to identification. However, the prediction on the degree of mixing from these relationships needs more detailed isotope data, although this study allows the oxygen isotopic composition of seawater as a tracer to identify the water mass.

• Ocean and Polar Research
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• v.26 no.4
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• pp.607-618
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• 2004

Zooplankton community was surveyed during the Seventh Korea Antarctic Research Program, from 28 December 1993 to 11 January 1994. Zooplankton samples were collected at 40 stations from the waters around the South Shetland Islands with a Bongo net and a MOCNESS. A total of 14 taxa of zooplankton were identified. Zooplankton abundances varied at each station as well as with the sampling gears. Zooplankton abundances were higher in the Western Weddell Sea than those in the Bransfield strait. Zooplankton collected with MOCNESS showed a different vertical distribution depending on its depths at selected stations. Copepods were the major components of zooplankton contributing 72.84% (mesh size $333{\mu}m$) and 68.36% (mesh size $505{\mu}m$) of total zooplankton abundance from the Bongo samples. Salps were the second most abundant group comprising 7.92% $(333{\mu}m)$ and 11.99% $(505{\mu}m)$ of total zooplankton abundance. Euphausiids, chaetognaths, polychaetes, pteropods and ostracods occurred more than 1% of total zooplankton. Copepods were not abundant at stations salps and euphausiids were dominant. Salpa thompsoni, Euphausia superba, Calanoides acutus, Metridia gerlachei and Calanus propinquus were dominant depending on the stations. The hierarchical UPGMA cluster analysis of dissimilarities between sampling stations is displayed with clusters identified similar habitats. Copepods rarely appeared in the clusters 4 and 5, and they appeared a ffw in the cluster 3 (or salps were numerous), while copepods were abundant in the clusters 1 and 2. As in the results of cluster analysis, the distributions of dominant taxa have a well identified correspondence to the geological positions included physical factors.

• Journal of the Korean earth science society
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• v.22 no.2
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• pp.130-137
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• 2001

A total of 58 species of radiolarians belonging to 41 genera were identified in 44 samples from core A9-EB2 of the Bransfield Basin in the Antarctic. The radiolarian assemblages from A9-EB2 are generally very low in abundance.The dominant species are Antarctissa denticulata, A. longa, A. strelkovi, Lithomelissa setosa, Lifhomitra lineata, Peridium longispinum and Phormacantha hystrix, constituting 75% of the total assemblage. Genera Challenge개n and Protocystis belonging to family Challeneriidae, found in core A9-EB2 have been recorded in the Quaternary sediments. Therefore, the geologic age of core A9-EB2 in Bransfield Basin is regarded to be Quternary (Pleistocene-Holocene). Typical circumpolar taxa such as Antarctissa strelkovi, A. denticulata, Cycladophora davisiana and Larcopyle buetschlii are representing the influence of waters from Bellingshausen Sea and Antarctic Circumpolar Current. Plectacantha oikiskos and Phomacantha hystrix are considered as a coastal indicator. Also, low amounts of Lithomelissa setosa are related to pelagic condition and entrance of cold waters from the Western Weddell Sea into Bransfield Basin. Therefore, the core sediments in Bransfield Basin were deposited under the coastal condition mainly influenced by the waters from Bellingshausen Sea and Antarctic Circumpolar Current. but also by the water from the Western Weddell Sea of the open-water condition.

• Ocean and Polar Research
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• v.24 no.1
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• pp.1-18
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• 2002

Seasonal variation in global transport calculated from an ocean general circulation model (OGCM) has been assessed through the comparison with observational estimates. The OGCM based on the GFDL MOM1.1 has honzontal grid interval of 10 and 21 verticle levels, and was integrated for 31 years forced by climatological wind stress, freshwater flux, and heat flux with restoring. General features of the world ocean circulation are well reproduced, which include the western boundary currents such as the Kuroshio and the Agulhas Current, the Equatorial Current system, the Antarctic Circumpolar Current, and the Weddell Sea gyres. Also well resolved is the remarkable seasonal variation in the depth-integrated flows in the northern Indian Ocean due to the monsoonal wind. Monthly variation is found to be dominant in the transport of the Antarctic Circumpolar Current through the Drake Passage in accordance with observational estimates. It has been shown that the mid-latitude depth-integrated flows obey the Sverdrup relation, except for some regions such as continental shelf regions where the interaction between stratification and bottom topography is critical.