• Proceedings of KOSOMES biannual meeting
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• 2004.05b
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• pp.89-92
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• 2004

Potential vorticity is useful to illustrate mechanism and distribution pattern of current circulation the upper layer in the East Sea is divided into three part following like surface layer, Tsushima Warm Current(TWC) layer. Potential vorticity shows well the meandering of the TWC and polar front and circulation cell ill the northern part of polar front.

• Journal of the Korean Geographical Society
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• v.51 no.2
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• pp.201-217
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• 2016

We accessed the climate change effects on the distributions of warm-evergreen broad-leaved trees (shorten to warm-evergreens below) in the Korean Peninsula (KP). For this, we first selected nine warm-evergreens with the northern distribution limits at mid-coastal areas of KP and climate variables, coldest month mean temperature and coldest quarter precipitation, known to be important for warm-evergreens growth and survival. Next, species distribution models (SDMs) were constructed with generalized additive model (GAM) algorithm for each warm-evergreen. SDMs projected the potential geographical distributions of warm evergreens under current and future climate conditions in associations with land uses. The nine species were categorized into three groups (mid-coastal, southwest-coastal, and southeast-inland) based on their current spatial patterns. The effects of climate change and land uses on the distributions depend on the current spatial patterns. As considering land uses, the potential current habitats of all warm-evergreens decrease over 60%, showing the highest reduction rate for the Kyungsang-inland group. SDMs forecasted the expansion of potential habitats for all warm-evergreens under climate changes projected for 2050 and 2070. However, the expansion patterns were different among three groups. The spatial patterns of projected coldest quarter precipitation in 2050 and 2070 could account for such differences.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.306-316
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• 2003

We conducted a time-series analysis of temperature and salinity of sea water around Jeju Island, Korea. Monthly mean temperature and salinity was influenced by precipitation and weather conditions on Jeju as well as by oceanographic conditions of the open sea such as the Tsushima Warm Current and sea water in coastal areas. Salinity of Jeju coastal waters was the highest in April, and it was always over 34.00 psu with tiny fluctuation between December and June. Due to the effects of the Tsushima Warm Current, Jeju coastal waters maintained high salinity and stability. Low salinity and its large fluctuations during summer were closely associated with the China Coastal Water and precipitation in Jeju. The place of the lowest water temperature was the northeast coasts of Jeju (Gimneong, Hado, Jongdalri). In winter, as warmer water of the Tsushima Warm Current appeared in western area of Jeju dwindled flowing along the northern coasts of Jeju area and becoming cool, the lowest water temperature often appeared locally in Gimnyeong and its vicinitly in summer. The Tsushima Warm Current flows into the east entrance of Jeju Strait, but its influence is weak because of geometry and strong vertical mixing due to fast tidal currents.

• 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).

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

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1385-1395
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• 2010

Harmful dinoflagellate Cochlodinium polykrikoides blooms have been frequently occurred in coastal areas of the East Sea since 1995. We compared the oceanic conditions in years 1995, 2001 and 2003 when the C. polykrikoides bloom was strong, and in years 1998 and 2004 when the C. polykrikoides bloom was not appeared. We studied temporal and spatial variation of upwelling and geostrophic currents on the western channel of Korean Strait, an entrance of the East Sea. The period and occurrence area of C. polykrikoides bloom was depended on variation of upwelling in summer. In the distributions of geostrophic current, southward current was dominant near the coast in August, 1998 and 2000. Whereas northward current was dominant near and off the coast in August, 1995 and 2003 which the C. polykrikoides bloom was strong. When compared dominant phytoplankton of the coastal areas in each year, Kuroshio indicator species Proboscia alata and Chaetoceros affine were dominant, respectively, in 2001 and 2003 at every stations. However, the dominant species was variable at each coastal area in 1998 and 2000. In 2003, the abundance of Sagitta elegans which is known as the cold water indicator was low, but the abundance of S. enflata, warm water indicator, was very high in Gangneung compared to Sokcho. It seemed that the distribution of S. elegans is restricted by strong warm water current. In conclusion, it was estimated that the distribution of C. polykrikoides bloom in the coastal area of the East Sea was closely related with the strength of East Korea Warm Current and upwelling.

• 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.

• Proceedings of the KSRS Conference
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• v.2
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• pp.926-929
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• 2006

Some features of vertical structure of the frontal interaction zone of the warm Kuroshio Current and cold Oyashio Current are known from 1930 from analysis of ship data. Ship data however do not allow carrying out the area detailed survey opposite to satellite infrared (IR) observations which possess by high spatial and temporal resolution. Analysis of NOAA AVHRR IR images demonstrated that process of formation and development of the Kuroshio warm core rings is highly complex. They are formed as a result of development of anticyclonic meanders of the warm Kuroshio waters and spin off them from the current. Joint analysis of thermal infrared images and altimetry data has also indicated that interaction of eddies to the frontal zone plays a crucial role in formation of large eddies moving to the Southern Kuril region.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.170-177
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• 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 Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.147-158
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• 1999

Warm or waste water discharged from offshore-based facilities often causes environmental polution as it is transported to coastal area due to tidal actions. In this research a floating-type current control structure is introduced in order to reduce the pollutant spreading in the coastal area. Effectivenss of the structure is investigated through the numerical experiment which is based on a 3-D finite difference multi-level scheme. The warm-water spreading in the bay is reduced when the draft of the structure increases and its optimum draft is found to be between 0.25h and 0.65h, where h is the water depth. The proposed structure is also tested in the Gohyun Bay and it ts proven to be applied to controllling pollutant spreading if its draft is properly chosen.