• 한국해양학회지
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• v.21 no.3
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• pp.136-145
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• 1986

Biotope analysis(UPGM) of the data on the total benthic foraminferal assemblage (Kim and Han, 1982) collected from the southeastern sea off the Korean Peninsula shows that foraminiferal assemblages are related to the water masses prevailing in the study area. South Proper facies is governed by the Tsushima Warm Current, and Southern Deep facies is influenced by the cold water mass moved down along the bottom. Northern Nearshore facies is governed by the North Korea Cold Current, and North Proper facies is affected by the North Korea Cold Current and Japan Sea Proper Water. It is also evident that the upper part of the study area is under the influence of the North Korea Cold Current rather than the East Korea Warm Current which flows northward along/or off the right side of the study area. Planktonic foraminiferal occurrence also supports this biotope analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.1
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• pp.61-73
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• 2016

Water mass distribution and currents were investigated off the east coast of Korea near the Hupo Bank using the CTD and ADCP data from June to August 2010. The typical water masses were: (1) Tsushima Surface Water (TSW) from the East Korean Warm Current (EKWC) in the surface layer, (2) a shallow thermocline at 20-30 m depth, (3) Tsushima Middle Water (TMW) of high salinity (>34.2) below the pycnocline, (4) North Korean Cold Water (NKCW) of low salinity (<34.05) and low temperature (<4°C) in the lower layer. In June, a double eddy was observed in which a cold filament intruded cyclonically from the south around a pre-existing cold-core eddy. A burst of strong southward current was recorded in mid-August due to a warm filament from the meandering EKWC. Current in the N-S direction was predominant due to topographic effects, and the direction of the northward EKWC was frequently reversed in its direction due to the eddy-filament activity, whereas the influence of the wind was not noticeable. The vertical structure of the current was of a two-layer system, with the northward EKWC in the upper layer and weak southward flows corresponding to the North Korean Cold Current (NKCC) in the deeper layer.

• Ocean and Polar Research
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• v.30 no.1
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• pp.21-31
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• 2008

Analyzing the results of East Sea Regional Ocean Model using a 3-dimensional variational data assimilation scheme, we investigated spatial and temporal variability of the North Korean Cold Current (NKCC) in the East Sea. The climatological monthly mean transport of the NKCC clearly shows seasonal variation of the NKCC within the range of about 0.35 Sv ($=0^6m^3/s$), which increases from its minimum (about 0.45 Sv) through December-January to March, decreases during March and May, and then increases again to the maximum (about 0.8 Sv) in August-September. The volume transport of the NKCC shows interannual variation of the NKCC with the range of about 1.0 Sv that is larger than seasonal variation. The southward current of the NKCC appears often not only in summer but in winter as well. The width of the NKCC is about 35 km near the Korean coast and its core is located under the East Korea Warm Current. The North Korean Cold Water (NKCW), characterized by low salinity and low temperature, is located both under the Tsushima Warm Water and in the western side of the maximum southward current of the NKCC that means the NKCC advects the NKCW southward along the Korean coast. It is revealed that the intermediate low salinity water, formed off the Vladivostok in winter, flows southward to the south of $37^{\circ}N$ through $2{\sim}3$ paths; one path along the Korean coast, another one along $132^{\circ}E$, and the middle path along $130^{\circ}E$. The path of the intermediate low salinity varies with years. The reanalysis fields suggest that the NKCW is advected through the paths along the Korean coast and along $130^{\circ}E$.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.10a
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• pp.103-107
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• 2001

The major studies of an ocean circulation of the East/Japan Sea related to evaluate the feasibility and utilization of deep ocean water are reviewed. The major feature of surface current system of the East/Japan Sea is an inflow of the Tsushima Warm Current through the Korea/Tsushima Strait and the outflow through the Tsugaru and Soya Straits. The Tsushima Warm Current has been known to split into two or three branches in the southern region of the East/Japan Sea. In the cold water region of the East/Japan Sea, the North Korean Cold Current turns to the east near 39$^{\circ}$N after meeting the East Korean Warm Current, then flows eastward. The degree of penetration depends on the strength of the positive wind stress curl, according to the ventilation theory. Various current meter moorings indicate strong and oscillatory deep currents in various parts of the basin. According to some numerical experiments, these currents may be induced by pressure-topography or eddy-topography interaction. However, more investigations are needed to explain clearly the presence of these strong bottom currents. This study concludes the importance of topographical coupling, isopycnal outcropping, different wind forcing and the branching of the Tsushima Warm Current on the circulation of the East/Japan Sea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.429-435
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• 2019

The drifters of the Global Drifter Program were deployed in the northern East Sea for two years from March 2015 to compare and validate currents estimated from sea-level measurements with the SARAL/AltiKa altimetry satellite mission, specially designed to accurately measure sea level in the near-coastal area. The collocated (less than 20 km apart) directly measured current from GPS locations every 30 minutes and the currents normal to the satellite tracks show a similar correlation in the area shallower than 200 m depth as the open ocean and it makes it possible to investigate the time variations of the current along the coast in the northern East sea, where direct observations of current are scarce. The Liman Current along the Siberian coast is found to be southward all year round, but the North Korean Cold Current flows southward only in the summer. The North Korean Cold Current south of the Musudan cape mostly flows to the south, but the current direction depends on the presence of an eddy around the coast of Musudan cape.

• Animal Systematics, Evolution and Diversity
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• v.14 no.4
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• pp.415-424
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• 1998

Twently seven speices of marine bryozoans from Namhaedo Island and its adjacent waters were identified. Among them, Hippothoa distans is new to Korean fauna and seven species are added as new to Namhaedo Island fauna. Twenty three species of them have been found also in Chejudo Island waters, which is affected by the Tsushima Current. Ten species have been found in the East Sea which is affected by both the Tsushima Warm Current and the North Korea Cold Current. So it is clear that the Namhaedo Island sea area is influenced by both the Tsushima Warm Current and the North Korea Cold Current.

• Journal of Environmental Science International
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• v.19 no.4
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• pp.399-406
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• 2010

Based on the Results of Annual Monitoring Report of Korean Marine Environment in 2006, it was shown that the coastal area of the East Sea around Korean peninsula could be clearly divided into two parts: the area of upwelling and the North Korean Cold Current. In the upwelling area, the chlorophyll-a and nutrients were increased by the influence of the decrease of temperature and the increase of salinity. These mean that the appearance of cold water due to the upwelling causes nutrient rich water and also resulted in the high productivity.

• 한국해양학회지
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• v.16 no.1
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• pp.12-23
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• 1981

A numerical experiment is made in order to clarify the mechanism of the upwelling phenomenon along the coast near the poleward edge of the western boundary current. The possibility of the upwelling is suggested from the analysis of the observational data in the east of Honshu, Japan, and in the south eastern coast of Korean Peninsula. This upwelling phenomenon is very deep and can be traced to the bottom layer. The upwelling phenomenon seems to be a general oceanic feature which characterizes the region along the west coast near the poleward edge of the western boundary current. This experiment is simulating the oceanic condition of the transition region between Kuroshio front and the Oyashio front in the east of Honshu, Japan. The possible explanations of the causes of the upwelling are as follows;In the interior of the modeled ocean the cold heavy water supplied from the north and the warm light water from the south make the north-south gradient of the pressure field and accelerate the eastward current to produce the h-orizontal divergence feld near the west coast. The divergence is compensated by the upwelling near the separation region. Another one is that the upwell-ed cold water strengthen constantly the pressure gradient which is balanced by the northward current and is weakened by the horizontal diffusion.

• 한국해양학회지
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• v.27 no.3
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• pp.189-196
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• 1992

A simple quasi-geostrophic model is considered to explain the separation of the East Korean Warm Current(EKWC) and formation of the North Korean Cold Current(NKCC). In this model, the circulation is driven by inflow-outflow condition and modified by local forcing. The solution is decomposed into inflow-outflow and local modes which describe only the effects of inflow-outflow condition and local forcing, respectively. Results of analyses show that both the surface cooling and positive wind stress curl are favorable for the separation of EKWC and formation of NKCC. This fact is compatible with the present knowledge about heat flux and wind stress field over the Sea of Japan.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.393-403
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• 2016

A steady, strong southward flow was observed in the lower layer beneath the Tsushima Warm Current in the deepest trough of the Korea Strait. Known as the Korea Strait Bottom Cold Water (KSBCW), this bottom current had a mean velocity of 24 cm/s and temperatures below 8–10℃. The direction of the bottom current was highly stable due to the topographic effects of the elongated trough. To determine the path of the southward bottom current, ADCP (Acoustic Doppler Current Profiler) data from 14 stations between 1999 and 2005 were examined. Persistent southward flows with average speeds of 4–10 cm/s were observed at only three places to the north of the strait where the bottom depths were 100–124 m. The collected data suggest a possible course of the southward bottom current along the southeast Korean coast before entering the deep trough of the Strait.