• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.138-150
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• 2003

In the mid-west coast of Korea where Mankyung and Dongjin rivers discharge fresh water, Saemangeum tidal dyke of 33 km long is under construction to reclaim the very shallow estuary region of 41,000ha. Main source of freshwater in this coastal area is Keum River locating closely north of the dyke. At present, the dyke connected with Gogunsan-Gundo separates this area into three regions; northwestern, southwestern and eastern (Saemangeum) region of the dyke, and the water in Saemangeum region is exchanged through one gap in the northern dyke and two gaps in the southern dyke. We have observed distributions and structures of temperature and salinity to examine the summer circulation related with low-salinity water in this coastal area in 1998 and 1999. In the surface layer off the northern dyke a tongue-like distribution of low-salinity extends 60 km long from Keum River estuary mouth to the northwest, forming plume front bounded by offshore water. In the inner region of Saemangeum dykes salinity distributions show that two river waters are merged together and the low salinity water is deflected toward northern gap of the dyke. In the surface layer off the southern dyke we observed small tongue-like distribution of another low-salinity water extending to the north from Gomso Bay. Based on the analysis of distributions of low-salinity water and frontal structures, we can suggest an anticlockwise circulation of coastal water around the dyke, composed by the estuarine water outgoing from the inner region of the dyke through the northern dyke's gap and the inflow through two gaps of southern dyke from offshore. After completing the dyke construction, this coastal circulation around the dyke will be, however, changed because fresh water discharge of Mankyung and Dongjin rivers will be routed artificially and directly into the area offshore of the southern dyke.

• Ocean and Polar Research
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• v.25 no.3
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• pp.287-302
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• 2003

The seasonal variations in the circulation of the water mass in the East Sea/Japan Sea have been simulated using a free surface primitive ocean model, RIAMOM (RIAM Ocean Model), comparing the results from GFDL-MOM1 (Geophysical Fluid Dynamics Laboratory Modular Ocean Model, version 1.1, hereafter MOM) with the GDEM (Generalized Digital Environmental Model) data. Both models appear to successfully reproduce the distinct features of circulation in the East Sea/Japan Sea, such as the NB (Nearshore Branch) flowing along the Japanese coast, the EKWC (East Korean Warm Current) flowing northward along the Korean coast, and the NKCC/LCC (North Korean Cold Current/Liman Cold Current) flowing southwestward along Korean/Russian coast. RIAMOM has shown better performance, compared to MOM, in terms of the realistic simulation of the flow field in the East Sea/Japan Sea; RIAMOM has produced more rectified flows on the coastal region, for example, the narrower and stronger NKCC/LCC than MOM has. There is however obvious differences between the model results and the GDEM data in terms of the calculation of the water mass; both models have shown a tendency to overpredict temperature and underpredict salinity below 50m; more diffusive forms of thermocline and halocline have been simulated than noted in GDEM data.

• Journal of the korean society of oceanography
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• v.35 no.4
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• pp.161-169
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• 2000

A seasonal circulation in the East China Sea and the Yellow Sea and its possible cause have been studied with CSK data during 1965-1989. Water mass distributions are clear in winter, but not in summer because the upper layer waters are quite influenced by atmosphere. To solve the problem, a water mass analysis by mixing ratio is used for the lower layer waters. The results show that the distribution of Tsushima Warm Current Water expands to the Yellow Sea in winter and retreats to the East China Sea in summer. It means that there is a very slow seasonal circulation between the East China Sea and the Yellow Sea: Tsushima Warm Current Water flows into the Yellow Sea in winter and coastal water flows out of the Yellow Sea in summer. By the circulation, the front between Tsushima Warm Current Water and coastal water moves toward the shelf break in summer so that the flow is faster in the deeper region. The process eventually makes the transport in the Korea Strait increase. The Kuroshio does not seem to influence the process. A possible mechanism of the process is the seasonal change of sea surface slope due to different local effects of surface heating and diluting between the East China Sea and the Yellow Sea.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.4
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• pp.241-257
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• 2004

Global prognostic models based on NCOM(NCAR CSM Ocean Model) of NCAR which is generic from Bryan-Cox-Semtner model are established to study the ocean circulation in the neighboring seas of Korean peninsula. The model domain covers areas from $80.6{^\circ}S~88.6{^\circ}N$in meridional direction and the vertical water column is divided into 15 levels taking enhanced grid resolution of $0.3^\circ$ around Korean peninsula. Island option is used for 22 islands to simulate inshore circulation by hole-relaxation method and the restart hydrographic data are taken from NCAR(1998) CSM model that has been run for 300 years. The wind stress data are taken from Choi et al. (2002). Based on the model results, circulation patterns in the NW Pacific and global oceans are investigated. Volume transports calculated at five straits in the neighboring seas of Korean peninsula are compared with the results from Choi et al. (2002) and other observed data.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2008.09a
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• pp.248-251
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• 2008

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2008.09b
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• pp.248-251
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• 2008

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1991.07a
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• pp.77-81
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• 1991

3차원 수치모형(Choi, 1989)을 이용하여 동지나해의 계절별 및 연평균의 풍성류 순환을 산정하였고, 이률 사용하여 동지나해의 분할된 여러 영역에서 수심별 해수 교체시간(turn-over time)을 계산하였다.(중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2001.08a
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• pp.108-118
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• 2001

• Journal of the Korean Society for Marine Environment & Energy
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• v.1 no.1
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• pp.93-101
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• 1998

Numerical models have been widely used to understand the structure of coastal currents and the transport mechanisms in regard to the fate of pollutants. This study focuses on the development of a three-dimensional model of coastal circulation and mass transport. The model was used to calculate coastal currents and temperature distributions of the thermal plume discharged from a power plant. The model results were compared with field-observed data. They showed the relatively good agreements with the data. The model can be used to estimate the currents and its mass transport in coastal waters.

• 한국해양학회지
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• v.19 no.2
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• pp.187-194
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• 1984

Water masses and circulation in the yellow Sea (Hwanghae) were briefly reviewed and synthesized. Water masses were classified into four types: Hwanghae Cold Water, Hwanghae Warm Current Water, Coastal Waters and Changjiang River Diluted Water. The Hwanghae Cold Water can be defined to have a salinity of 32.0∼33.0% and a temperature below 10$^{\circ}C$, based on long-term hydrographic data and recent CTD casts (KORI, 1984). Concerning circulation, there exists a cyclonic gyre throughout the year in the southern part. In winter, the coastal current along the Chinese coast is very strong due to northerly or northwesterly winds and the Hwanghae Warm Current becomes weak as can be expected from a surface to bottom thermohaline front west of Cheju-do. Meanwhile in summer, the Changjiang River Diluted Water flows northeastward toward Cheju-do and the coastal current in the western part is greatly reduced. The northward current during summer in the southeastern Hwanghae has been accepted to be the Hwanghae Warm Current until now, coastal waters and the Hwanghae Cold Water in the central deep area, not a continuation of the Hwanghae Warm Current.