• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.1
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• pp.58-64
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• 1992

A barotropic model is run over the Northwest Pacific Ocean to examine the formation and transport of the Tsushima Warm Current. The results indicate that the Tsushima Warm Current is a downstream extension of the Taiwan Warm Current. Local wind does not change the amount of transport of Tsushima Warm Current but it changes much the initial flow pattern of Tsushima Warm Current such that for southerly wind, the transport is through the Taiwan Strait but for northerly wind, it is through the eastern side of Taiwan.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1994.07a
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• pp.14-18
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• 1994

Barotropic Model을 이용하여 바람의 계절변화에 따른 대마난류의 형성을 살펴보았다. 모델 격자간격은 위도와 경도방향 모두 $0.25^{\circ}$로 하였고 바람은 Hellerman & Rosenstein (1983)의 바람을 이용하였다. 모델결과에 의하면 대마난류는 대만해협이 음의 유선함수 (Stream Function) 값을 갖는 동계 (10월-3월)에는 쿠로시오로 부터 직접 분기되어 형성되며 대만해협이 양의 유선함수값을 갖는 하계 (4월-9월)에는 대만해협을 통해 유입된 대만난류가 대마난류의 기원으로 나타난다. 이러한 대만난류 유입경로의 계절변화는 쿠로시오 수송량의 계절변화에 의한 것이 아니라 연해 (동지나해) 에서의 바람의 계절변화에 의해 야기되는 것으로 사료된다. 대한해협과 대만해협에서의 수송량과 쿠로시오의 수송량변화는 각각의 최대, 최소값만을 고려하면 쿠로시오와 대한해협에서의 수송량 변화는 약 $180^{\circ}$의 위상차를 갖으며, 대만해협에서의 수송량변화는 북풍계열의 바람이 우세한 동계를 제외하고는 쿠로시오의 수송량변화와 같은 위상을 갖는다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.160-161
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• 2000

동지나해로부터 동해로 유입되는 대마난류의 계절변동과 수송량에 관한 많은 연구가 대한해협에서 수행되어왔다. 이러한 연구들은 수문학적 자료로부터 Margule's equation으로 대한해협을 통과하는 수송량을 계산하거나 부산, 이즈하라와 하카타의 해수면 변동자료로 각 지점간의 해면차와 대한해협에서 실제 관측한 유속 또는 평균 지형류와의 관계를 연구했다. 또한 대한해협의 몇개의 지점에 대하여 ADCP와 CTD 관측을 통해서 대마난류의 실제유속과 지형류적 유속을 비교였다. (중략)

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.4
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• pp.364-374
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• 1994

The separation mechanism of the Tsushima Warm Current and the effects of seasonal wind stress on the separation position are studied by use of a barotropic numerical model. The grid spacing of 0.25$^{\circ}$ both in latitude and longitude is used in the model, and Hellerman and Rosenstein's wind (1983) is applied to the sea surface as seasonal wind stress. According to the model results, during winter seasons (from October to March) when northly wind is prevailing, the Tsushima Warm Current is formed by direct separation from the Kuroshio on the continental slope southwest of Kyushu. On the other hand, during summer seasons (from April to September), the Taiwan Current that flows through the Taiwan Strait seems to be the origin of the Tsushima Warm Current. The Kuroshio reaches its maximum transport during winter seasons, and the minimum during summer. The transport of the Taiwan Current shows a phase lag of about 160$^{\circ}$ relative to the Kuroshio. The transport variation of the Tsushima Warm Current agrees with that of the Kuroshio when the former is shifted by 120$^{\circ}$(about 4 months).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.439-447
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• 2019

Some dynamical issues about the Tsushima Warm Current (TWC) are reviewed and checked for the remaining unresolved problems, focusing on the formation of the TWC, seasonal variation of its volume transport and its branching in the East Sea. The TWC is a part of the North Pacific (NP) subtropical gyre driven by the NP global wind system. However, the quantitative amount of volume transport is sensitive to friction, basin geometry, barrier effect and so on. Among many causes suggested by many scientists, subpolar winds are found to be most closely related with the seasonal variation of TWC volume transport. However, more studies relating the latter not only to the subpolar winds but also to those including the subtropical winds seem to be required. The branching of the TWC has been known to be due to the western intensification for the East Korean Warm Current (EKWC) and to the bottom trapping for the Nearshore Branch. Since the former hypothesis is problematic in explaining the seasonal variation of the EKWC, other candidate mechanisms may need to be considered.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.240-241
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• 2001

대한해협은 대마난류가 동해로 유입되는 통로이고 대마난류의 변동은 동해의 해수순환에 많은 영향을 준다 대한해협에서 해류에 대한 연구는 지형류계산에 의한 것(Yi, 1970)을 시작으로 해류계의 계류관측이 여러차례 수행되었으나(Shim et at, 1984; Lee et al, 2001), 대부분 20∼40일 정도의 단기간에 한정되어 해류의 장주기 변동성을 규명하는데 어려움이 많았다 본 연구에서는 장기간에 걸친 해류관측자료를 이용하여 대한해협의 조류 및 해류의 연직구조와 그 변동성을 자세히 알아보았다. (중략)

• 한국해양학회지
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• v.18 no.1
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• pp.1-9
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• 1983

The northern boundary of the Tsusgima Current and its fluctuations are divcussed in the Japan Sea in summer. This current was characterized with high slinity, and its path was traced by following the salinity maximum on the basis of oceanographical data collected during the period from 1963 to 1979. The salinity maxima (34.45-34.85 ) of the Tsushima Current in the areas between 29 N in the East China Sea and northern part of the Japan Sea were found at depths between 46m and 135m. The representative thermosteric anomaly corresponding to the salinity maximum eas examined in order to analyze the advection of this currint. In the Tsushima Current region in the Japan Sen, the thermosteric anomaly values in the layer of salinity maximum during the period of 1970 to 1979 was beween 220 cl/t and 260 cl/t. In general, as the current moves northward its salinity decreascs, its thermosteric anomaly decreases and the depth of salinity maximum becomes shallower. The northern boundary of this current, which is indicated by 34.4 isohaline on 240 cl/t isanosteric surface during the study period of ten years, was confined to south of 40 N of the Japan Sea. The 34.4 isohaline edvealed two types of flow; one of them flows northward along the eastern coast of South Korea and then meanders eastward, while the oter flows basically northeastward along the coast of Japan. The meanders of northern boundary of this currint idrntified th isohaline in this word were nearly similar to those studied by others on the bases of isotherm analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.291-297
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• 1983

This paper describes the variations of the distribution of dissolved oxygen in the Japan Sea in summer during 1974-1977. In the Tsushima Current region of the Japan Sea the salinity maxima appears frequently in summer and the dissolved oxygen at the salinity maximum is less than that in the Japan Sea Proper Water. The Japan Sea is divided into three parts with respect to the type of vertical profiles of dissolved oxygen: The southern region of about $35^{\circ}N$ which has low dissolved oxygen similar to those in the Kuroshio region, the Japan Sea Proper Water region, and the area between about $36^{\circ}N$ and $40^{\circ}N$ which has high dissolved oxygen. The ranges of the dissolved oxygen and thermosteric anomaly(${\delta}_T$) at the salinity maximum are roughly between 4.9 and 6.5 m/l and between 210 and 240 cl/t respectively. The most frequent ranges of those values are between 5.5 and 5.7 ml/l and between 230 and 240 cl/t. The northern boundary of the Tsushima Current can be known by the characteristics of the distribuion of dissolved oxygen.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.226-244
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• 1998

The relationship between the transport of eggs and larvae of Anchovy (Engraulis japonica) and the oceanic condition in the southern sea of Korea was examined on August and November 1996. In summer (August), when the Tsushima Warm Current is strong near to the coast, the warm waters such as warm streamers from the Tsushima Warm Current intrude into the coastal area, and cyclonic circulations are formed. The warm water intrusions also generate wakes around Komun Island, Sori Island and Koje Island. In the coastal area where the warm water intrusions occur, the nutrients, dissolved oxygen, suspended solid and chlorophyll are concentrated in probably relation to the upwelling concerned with this warm streamer and/or the wakes. Anchovy eggs and larvae are transported to the coastal area by the cyclonic circulations. The hatching and growth of anchovy larvae are increased because of high primary production in the cyclonic circulations. However, as the amount of Copepods which are a main food for anchovy larvae decrease in the coastal area, anchovy larvae seem to move to the Isushima Warm Water area for seeking a prey. In autumn (November), the Tsushima Warm Current is far away from the coast. In this season the warm water intrusions almost disappear, and the small scaled frontal eddies are formed between the coastal water and the Tsushima Warm Water. As the surface water moves towards offshore, few anchovy eggs and larvae were sampled in the survey area. Chemical and biological substances are concentrated in the leftdown sides of the small scaled frontal eddies because of eddy formation.

• 한국해양학회지
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• v.19 no.2
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• pp.200-209
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• 1984

On the basis of oceanographic observation conducted in summer 1982, the flow pattern of the Tsushima Warm Current definitely showed two branches with high surface velocity more than 70 cm/sec in the western channel of Korea Strait. One of the branches, the East Korea Warm Current, found about 8 km off Pusan flows northward along the east coast of Korea and the other branch, located at about 20km off Pusan flows east after passing the Korea Strait. The branching of two flows already occurred before the Tsushima Warm Current reaches the Pusan Tsushima section, and the volume transport and the widths of the two branches are not much different from each other. The number of branches may be controlled by the width of western channel and the flow of two branches may also be related to the variation of layer depth and the widening ratio of widths between the western channel and the Japan Sea (East Sea).