• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.36 no.2
• /
• pp.170-177
• /
• 2003

This study is to analyze the influence of the Tsushima Warm Current (TWC) on the variation of sound speed in the southern part of the East Sea. Sound speed is calculated by method of Chen and Millero (1977:, based on the CTD data measured in June of 1996. Sound speed in the central part of the TWC is about $45ms^{-1}$ more fast than that in the other regions without the TWC. Sound speed minimum layer (SML) in the TWC region exists between loom and 341 m, while it exists between 260m and 290m in the non-TWC region. SML distributes along the path of TWC over continental shelf in the coastal waters of Japan.

• Journal of Environmental Science International
• /
• v.12 no.9
• /
• pp.943-948
• /
• 2003

Variation of the polar front in the East Sea is studied using temperature and dissolved oxygen data obtained from Japan Meteorological Agency from 1972 to 1999. Variation of the polar front in the East Sea has a close relation to the variation of the Tsushima Warm Current (TWC). When the TWC spreads widely in the East Sea, polar front moves northward. The spatial variation of the polar front is greater in the southwestern area of the East Sea and the northern area of Tsugaru Strait where the variation of the TWC's distribution area is greater than those in others of the East Sea. Hence, in the southeastern area of the East Sea, that is, between near Noto peninsula and Tsugaru Strait, the spatial variation of the polar front is not so wide as in the southwestern area because the flow of TWC is stable.

• Journal of the korean society of oceanography
• /
• v.32 no.1
• /
• pp.8-16
• /
• 1997

The ventilation theory developed by Luyten, Pedlosky and Stommel (1983) is applied to the East Sea to understand the general circulation pattern of the Intermediate Water, especially the ventilated circulation beneath the Tsushima Warm Current. The original model is slightly modified such that it takes the inflow-outflow of the Tsushima Current into consideration. Results of the model indicate that for sufficiently strong Ekman pumping, the Intermediate Water circulates cyclonically by ventilation. The Intermediate Water subducts beneath the Tsushima Warm Water through the western boundary layer. Off the western boundary layer, it turns northward, outcrops to the north by passing the polar front and continues to flow northward until it finally is absorbed by the northern boundary layer. This result seems to be compatible with some recent observations. Over the ventilated area, the transport of the Tsushima Current is negligible and most transport occurs in the shadow area where the Intermediate layer is motionless indicating that, over the deep motionless layer, the two-layered vertical structure under consideration becomes substantially single-layered.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
• /
• 1995.10a
• /
• pp.16-19
• /
• 1995

Effects of the changes in bottom topography and non-linearity of the western boundary current on the separation position of the Tsushima Warm Current(TWC) are investigated using a primitive equation model in a simplified model domain which consists of a deep ocean, a continental shelf and a marginal sea(Fig. 1). (omitted)

• Animal Systematics, Evolution and Diversity
• /
• v.14 no.4
• /
• pp.415-424
• /
• 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 the korean society of oceanography
• /
• v.31 no.1
• /
• pp.23-31
• /
• 1996

The thermo-haline front frequently observed near the southwestern tip of Korean Peninsula is successfully modeled using a simple model. The front is formed by the wind-driven advection of local cooled water to the southern warm area which is kept warm by large heat advection of the Tsushima Current. The front thus locates north of the Tsushima Current which runs approximately along the isobaths in the east-west direction.

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

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.16 no.4
• /
• pp.299-304
• /
• 1983

A tongue-like warm water which is a part of the Tsushima Warm Current appears whole year around in the east entrance of the Jeju Strait. Because of this warm water, the current direction flowing into the Jeju Strait from its west area seems to be changed in the Jeju Strait. Therefore the intermediate and bottom water of the Jeju Strait may greatly influence the formation of the coastal water in the South Coast of Korea. Since this tongue-like warm water is stronger in winter than in summer in its formation, Tsushima Warm Current comes closer to the South Coast of Korea in winter and its north boundary frequently approaches close to the coast of Geomun Island and Sori Island.

• Ocean and Polar Research
• /
• v.42 no.2
• /
• pp.97-113
• /
• 2020

In-situ observations were carried out in April 2015 to investigate the occurrence of water temperature inversion in a region west of Jeju Island. Analysis of in-situ in the western part of Jeju island showed that cold water moved to the southeast from the surface to the middle layer and warm water moved from the middle to the lower layer of the northwest direction. The water temperature inversion occurred at 84 stations (63.1%) out of 133 stations. At the boundary of the water temperature inversion layer, it was formed in the middle layer and disappeared. In the strongly appearing, it started from the middle layer to the lower layer. The shape of the water temperature inversion layer was different. As a result of horizontal water temperature slope analysis of the water temperature inversion zone, maximum 0.23℃/km was obtained and the mean was 0.06℃/km. The role of water temperature inversion as an indicator to determine the formation of water front. As a result of the water mass analysis, Jeju Warm Current Water and Tsushima Warm Current Water of high temperature and high salt intruded from the middle to the bottom. In the middle layer occurred as the Yellow Sea Cold Water of low water temperature and low salinity expanded.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.37 no.2
• /
• pp.148-158
• /
• 2004

In the adjacent seas of Cheju Island, the oceanographic conditions show low salinity surface waters starting in May. This water flows from the southeast part of the China Coastal Water, which flows southeastward along the Great Yangtze Sand Bank until April, with the help of southeasterly winds and flows from the adjacent sea off Cheju Island. In May, the Tsushima Warm Current and the low salinity surface water fluctuate in short and long-term periods as influenced by Yellow Sea Cold Water, which flows to the bottom layer at the western entrance of Cheju Strait. Temperature and salinity fronts in the northeastern sea area of U Island are formed in the boundary area between the Tsushima Warm Current, which expands towards Cheju Island from the southeastern sea area of Cheju Island and Hows out from the eastern entrance of the strait. Seasonally, additional oceanographic conditions, such as coastal counter-currents, which flow southward, appears within limited areas in the adjacent eastern and western seas of Cheju Island.