• 한국해양학회지
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• 제20권2호
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• pp.22-27
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• 1985

韓國 東海岸에서 夏季 沿岸流를 調査하기 위해 注文津 沿岸海域에서 海水의 物理特性 및 海流를 觀測하였다. 物理特性結果는 0∼100m 층에서 等溫線 等鹽分線, 等密度線이 沿岸으로 갈수록 下降하고 沿岸에서 外海로의 鹽分, 密度의 水平기가 比較的 强하게 存在하고 있음을 보였다. 最大 流速이 70cm/sec에 달하는 海岸線에 平行한 强한 南向流가 發見되었으며 觀測流의 流速과 shear가 地衡流와 大體로 一致하였다.

• Journal of the korean society of oceanography
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• 제37권4호
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• pp.212-223
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• 2002

Cochlodinium polykrikoides bloom in 1995 was studied with a focus on an unusual coastal environment in the South Sea of Korea. Data on temperature, salinity, and zooplankton biomass during 1965-1998 and nutrients during 1990-1998 and chlorophyll-a during 1995-1998 were used in this study. These data were obtained from the serial oceanographic observations in Korean waters carried out by the National Fisheries Research and Development Institute. In 1995 the C. polykrikoides bloom began in the coastal area around Narodo Island in August and consequently occurred to the whole coastal area of the South and East Seas of Korea. During June-October 1995, the coastal environment was unusual compared with the long-term means during 1965-1998. In June 1995, sea surface temperature was 1-2$^{\circ}C$ warmer than in other years in all coastal areas, while salinity was high only to the east of Jeju Island. In August 1995, a strong coastal front appeared inshore of a line between Jeju and Tsushima Islands. In particular, a strong coastal front which showed the characteristics of upwelling front occurred in the coastal area around Narodo and Sorido Islands, not only because of a strong intrusion of the Tsushima Warm Current but also because of the upwelling of cold bottom water. Salinity was low in the neighboring waters of western side of Jeju Island. Nutrients and chlorophyll-a were high in the inshore area between Narodo and Sorido Islands in 1995 in contrast with the other years and areas. Zooplankton showed an unusually high abundance in the coastal area in October 1995. We conclude that the Tsushima Warm Current strongly influenced the South Sea of Korea in 1995 and created strong upwelling front bordering cold upwelled water in the coastal area around Narodo and Sorido Islands. It leads us that these physical structures introduce the favorable environment for the development of C. polykrikoides blooms. We suggest that C. polykrikoides has a bio-physical tolerance of high shear and stress and prefers frontal and upwelling relaxed areas as its habitat. We also find that nutrients were not supplied to the coastal area from the offshore where a low salinity water mass with high nutrients appeared around Jeju Island. Because the strong upwelling front protect the reach of offshore low saline water mass. The main source of nutrients was the upwelled water mass in the coastal area of Wando-Narodo-Sorido.

• Journal of the korean society of oceanography
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• 제38권3호
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• pp.87-100
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• 2003

The monthly observations of hydrography in the Cheju Strait from September 1995 to June 1998 show that the Cheju Strait is occupied mostly by Tsushima Current Water in winter and coastal waters in summer. In summer, the Yangtze Coastal Water appears in the upper layer and cold water in the lower layer. Especially, the Yellow Sea Bottom Cold Water appears in August 1997, and the clockwise flow of warm water along the northwestern coasts of Cheju Island is disturbed by an eastward expansion of the cold water from the northwest. The cold water expansion seems to be partly associated with strong southeasterly winds. Current measurements in the Cheju Strait suggest that there exists steady eastward barotropic component of about 5 cm/sec, which corresponds to 0.2 Sv barotropic transport in the Cheju Strait. Geostropic transport (baroclinic component) ranges from 0.1 Sv in winter to 0.4 Sv in summer. By adding the barotrophic component of 0.2 Sv, the total transport varies from 0.3 Sv to 0.6 Sv, which is consistent with previous estimations. The transport increase in summer seems to be caused by the expansion of coastal water to the Cheju Strait.

• Ocean and Polar Research
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• 제33권spc3호
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• pp.397-407
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• 2011

To understand the vertical structure of ocean currents from raw data observed by lowered-ADCP (LADCP), these data require post-processing. Data were processed using Krahman's version 10.8 processing software based on Matlab. It is estimated the influence of auxiliary data affecting the processed current structure. The bottom-tracked velocities and the GPS information significantly contribute the offset on reference velocities in the bottom layer and barotropic ones in the middle layer, respectively. Good quality data can be obtained when LADCP is least tilted in pitch and roll during observation. In situ application of LADCP to the (northward) volume transports of Kuroshio in the East China Sea proved to be 24.8. Sv (= $1{\times}10^6m^3s^{-1}$) in October 2007, and 28.2 Sv in June 2008, respectively. The volume transport is relatively large over the continental slope when compared to the shelf or the deep sea.

• International Journal of Naval Architecture and Ocean Engineering
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• 제3권3호
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• pp.216-224
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• 2011

In This study develops a quasi-three dimensional numerical model of wave driven coastal currents with accounting the effects of the wave-current interaction and the surface rollers. In the wave model, the current effects on wave breaking and energy dissipation are taken into account as well as the wave diffraction effect. The surface roller associated with wave breaking was modeled based on a modification of the equations by Dally and Brown (1995) and Larson and Kraus (2002). Furthermore, the quasi-three dimensional model, which based on Navier-Stokes equations, was modified in association with the surface roller effect, and solved using frictional step method. The model was validated by data sets obtained during experiments on the Large Scale Sediment Transport Facility (LSTF) basin and the Hazaki Oceanographical Research Station (HORS). Then, a model test against detached breakwater was carried out to investigate the performance of the model around coastal structures. Finally, the model was applied to Akasaki port to verify the hydrodynamics around coastal structures. Good agreements between computations and measurements were obtained with regard to the cross-shore variation in waves and currents in nearshore and surf zone.

• 한국해안·해양공학회논문집
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• 제32권2호
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• pp.122-134
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• 2020

최근 동해안을 비롯한 많은 해안에서 심각한 해안침식과 인접한 해안도로 유실 등과 같은 연안재해가 발생되고 있는 것은 널리 알려진 사실이다. 이에 대한 대안으로 유럽을 비롯한 해외에서는 저마루구조물(LCS, Low-Crested Structure)에 의한 연안재해 저감법이 활발하게 연구되고 있다. 본 연구에서는 선행연구를 바탕으로 투과성의 LCS 및 그의 주변 파동장에 olaFlow 모델을 적용하여 불규칙파동장 하의 3차원 수치해석을 수행한다. 이로부터 H_rms, 해빈류 및 평균난류운동에너지를 수치적으로 검토하며, 해빈류의 패턴과 평균난류운동에너지의 공간분포에 관해서는 불규칙파동장 하 잠제의 경우와 비교하였다. 이로부터 해빈류의 양상이 잠제의 경우와는 상반되게 나타나는 등의 중요한 결과를 얻을 수 있었다.

• 수산해양교육연구
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• 제27권3호
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• pp.747-756
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• 2015

Brown alga Undaria peterseniana has been interested in the commercial scale aquaculture for warm water species development in southern coastal area of Korea. However, this species was classified an endangered species caused by a decrease in habitat and natural population. In this study, inhabit characteristics of U. peterseniana was investigated in their natural habitat of Ulleung Island, Korea. The U. peterseniana population was occurred dense patches at 20~30m depth. Total length of the alga reached 1.0~2.0m and the largest width ranged 10.0~35.0cm during the study. In 2013, habitats of this species increased two sites compared with the previous year and their distribution extended to low depth (10m) of coastal area. In long-term data, seawater temperature revealed a continuous increment by strong going north of East Korea Warm Current or Ulleung Warm Eddy turning around the coast of Ulleung Island. It suggested that habitat extension of U. peterseniana may be caused by suitable settlement condition and increase of warm water around the coastal area. Current studies of this species may be continuously required in the possibility of fisheries resources as aquaculture species and index species of increment of water temperature at the fixed monitoring site in East Sea. This is the first study to research ecological feature U. peterseniana population at the natural habitat of Ulleung Island.

• 한국해안해양공학회지
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• 제5권4호
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• pp.414-426
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• 1993

황해 및 동중국해륙붕에서 해류관측에 이용되는 현대적인 방법들을 기술하였고 이 해역 해류의 변화도를 해류관측방법과 관연하여 토의하였다. 이 육붕해역의 보고된 해류관측의 총체적인 자료수집을 수행하였다.

• 한국해안해양공학회지
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• 제6권4호
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• pp.421-438
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• 1994

대한해협 조류의 3차원적 분포를 3차원 조석모형에 의해 산정하였다. 모형의 결과는 8개분조의 조석도(등진폭도와 등위상도) 및 조류타원도로서 제시되었으며 또한 이 해역의 특정기간의 조석예보를 위한 분조의 조화상수의 data table로서 작성되었다. 모형의 조석산정결과는 연안관측치와 관측치를 근거한 Odamake(1989)의 조석도와 전선적인 일치를 보였으며 구주대학 응용역학연구소의 조석관측치를 이용한 검증도 수행하였다.

• 한국환경복원기술학회지
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• 제2권3호
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• pp.64-73
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• 1999

The purpose of this study is to establish the management plannings for the conservation and environmentally friendly use of Korean coastal wetlands. The function, economic value, and the necessity for the conservation of coastal wetlands are described. The current management status, Korean Governmental policies for the use of coastal wetlands, and their problems are surveyed and analysed. The management plannings for the environmentally friendly use of Korean coastal wetlands is suggested as follows: (1) The coastal wetlands need to be divided into 3 different regions based on PSR(Pressure, State, Response) of OECD. (2) Each region should be managed by appropriate management plans which are suggested in Chapter IV of this paper. Finally, in order to realize these management plannings the change of Governmental system and laws are suggested as follows: (1) The change of relevant laws is required. Additionally, each region should managed by proper governmental agencies. (2) The EIA(Environmental Impact Assessment) system should be improved. (3) The participation of regional people should be guaranteed in the decision making processes of the business and other important planning regarding coastal wetlands. (4) The system which primed the ecological value of coastal wetlands should be established.