• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.280-281
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• 2008

본 연구 결과에 의하면, 창조류 분포는 외해에서 유입된 북향류의 일부가 오동도 주변 방파제를 돌아서 신항 내부로 유입되는 양상과 가막막과 연결된 좁은 해협에서 압류되면서 유속이 증가하는 특성을 잘 보여주고 있다. 낙조류는 광양만을 빠져나온 남향류의 일부가 신항의 북방파제에 부딪히면서 신항에서 유출되는 수괴와 만나 오동도 주변 방파제를 돌아나오면서 가막만에서 유출되는 수괴와 합류하여 외해로 빠져나가는 분포를 보여주고 있다. 여수 신항의 해수유동은 주변 해역에 비해 아주 미약한 것으로 관측되었으며 항내 수질 및 환경 개선을 위해서는 유입원의 제거와 함께 해수 및 물질 교환을 위한 방안이 마련되어야 할 것으로 판단된다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.452-454
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• 2001

우리나라 서해안에 위치한 함평만은 만 입구의 폭이 만 내의 폭에 비해 상당히 좁아 1.8km정도 밖에 안 되는 반폐쇄적인 만이다. 또한, 창조류보다 낙조류가 우세하고 외해의 영향을 많이 받지 않는 독특한 환경으로서 침식작용보다는 퇴적작용이 우세한 곳이다. 본 연구에서는 함평만 펄 조간대에 서식하는 저서동물의 군집 구조를 파악하고 주요 우점종들의 공간분포 양상을 파악하고자 하였다. (중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.188-195
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• 2018

Time series analysis was conducted to identify the factors affecting short-term variation of water temperature in Wando. Spectrum analysis showed that air temperature peaks at diurnal period, while water temperature and tide level peak at both semi-diurnal and diurnal periods. Coherence between water temperature and the tide level presented 0.92 at semi-diurnal period. Numerical experiment were carried out to understand the spatio-temporal distribution of water temperature in the study area. Average water temperature difference between maximum ebb and flood was $0.3^{\circ}C$ in spring tide, but $0.13^{\circ}C$ in neap tide. The reason for the large difference in spring tide is that relatively cold water entered with strong tidal currents at flood tide and flowed out at ebb tide. Water temperature on coasts was higher than out at sea. This is because the depth in the coast is shallower than at sea, and water temperature increases rapidly due to solar radiation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.6
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• pp.352-358
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• 2014

Hourly tide-gauge data at 10 tide stations along the West/South coasts were analysed statistically for tidesurge interaction. Interactions were found at all stations except Busan, prominently at the western tip of the South coast near Mokpo and Wando. A well-known interaction pattern which occurs at flood tide was found rarely at domestic coasts, while another pattern of the tide-modulated surge which occurs at low tide was detected frequently. In addition, a new interaction pattern which occurs at ebb tide is discovered. This pattern is found at Mokpo where the ebb dominance is prominent. Finally, the skew surge could be considered as a tool coping with such interactions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.2
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• pp.129-135
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• 1999

The telemetry system for the current speed and direction, the underwater ambient noise and the distribution ecology of fishes was constructed by the author and his collaborator in order to product and manage effectively in shallow sea culture and setnets fisheries, and then the experiments for the telemetry system carried out at set net fishing ground located Nungpobay in Kojedo from October 1996 to June 1997. As this results, the techniques suggested in the telemetry system gave full display its function even though far away 1.5 km from transmitting part, but with the suggested telemetry system could not be ascertained relationship between physical environment and distribution ecology of fishes.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.8 no.1
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• pp.103-113
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• 1996

Two-dimensional finite element hydrodynamic models for long wave simulation usually adopt fixed land boundary. However moving boundary treatment is strongly required in the simulation of tidal flats for west and south coast of Korea. In this study very efficient and realistic moving boundary treatment is applied by considering incident long wave surface slope. Developed STEP-CM (Superior Two-step Explicit Program for Coastal Modeling) ,shows numerically stable results in comparative study for idealized one-dimensional channel. Real application of the model is done for Chonsu Bay where tidal flats are distributed along the coast. Nonlinear tidal current and tidal flat effects are easily simulated in STEP-CM and resulting circulations are detected around headland of Wonsan Island.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.105-118
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• 2000

Anchored measurements (12.5 hr) of suspended sediment concentration and other hydrodynamic parameters were carried out at two stations located at the entrance to Hampyung Bay in summer (August 1999). Tidal variations in water temperature and salinity were in the range of 26.0-27.9$^{\circ}C$ and 30.9-31.5, respectively, indicating exchange offshore and offshore water mass. Active tidal mixing processes at the entrance appear to destroy the otherwise vertical stratification in temperature and salinity in spite of strong solar heating in summer. On the contrary, suspended sediment concentrations show a marked stratification with increasing concentrations toward bottom layer. Clastic particles in suspended sediments consist mostly of very fine to fine silt (4-16 ${\mu}$m) with a poorly-sorted value of 14.7-25.9 ${\mu}$m. However, at slack time with less turbulent energy, flocs larger than 40 ${\mu}$m are formed by cohesion and inter-collision of particles, resulting in a higher settling velocity. Strong ebb-dominated and weak flood dominated tidal currents, in the southwestern and the northeastern part, respectively, result in a seaward residual flow of -10${\sim}$-20 cm $s^{-1}$ at station H1 and a bayward residual flow less than 5.0 cm $s^{-1}$ at station H2. However, mean concentration of suspended sediments at station H1 is higher at flood (95.0-144.1 mg $1^{-1}$) than in ebb (75.8-120.9 mg $1^{-1}$). On the contrary, at the station H2, the trend is reversed with higher concentration at the ebb (84.7-158.4 mg $1^{-1}$) than that at the flood (53.0-107.9 mg $1^{-1}$). As a result, seaward net suspended sediment fluxes ($f_{s}$) are calculated to be -1.7 ${\sim}$-$15.610^{3}$ kg $m^{-2}$ $s^{-1}$ through the whole water column. However, the stations H1 and H2 show definitely different values of the flux with higher ones in the former than in the latter. Alternatively, depth-integrated net suspended sediment loads ($\c{Q}_{s}$) for one tidal cycle are also toward the offshore with ranges of 0.37${\times}$$10^{3}$ kg $m^{-1}$ and 0.21${\times}$$10^{3}$ kg $m^{-1}$, at station H1 and H2, respectively. This seaward transport of suspended sediment in summer suggests that summer-time erosion in the Hampyung muddy tidal flats is a rather exceptional phenomenon compared to the general deposition reported for many other tidal flats on the west coast of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.61-67
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• 1975

Oceanographic conditions of the coastal water around Chungmu, one of the most important oyster farming areas in Korea, were studied from May to November in 1974 to find out the environmental influence to oyster farming. Six localities, Goseong Bay, Jaran Bay, off Saryangdo, Hansilpo, Tong-yeong Bay and Juklimpo were selected for monthly oceanographic observation and biological sampling. Flood current running westward brings saline water from the south-east and ebb current brings the low salinity water of Jinju Bay into this area. The waters in Juklimpo, Hansilpo and Tong-yeong Bay are slightly cooler and more saline than the waters in Goseong Bay, Jaran Bay and off Saryangdo. The amount of dissolved oxygen is lowest in September and Hansilpo has the least oxygen during summer. Silicate content is lower in waters of Tong-yeong Bay, Juklimpo and off Saryangdo than those of Goseong Bay, Hansilpo and Jaran Bay. Suspended matter in this area ranges from 7.4 to 16.6 mg/l and scarce in Jaran Bay, Juklimpo and off Saryangdo. Chlorophyll a shows large seasonal variation and local fluctuation. Composition of phyto-plankton reveals the difference between the waters of Goseong Bay, Jaran Bay and off Saryangdo and the waters of Hansilpo, Tong-yeong Bay and Juklimpo. The growth of oyster was good in Juklimpo, Tong-yeong Bay and Goseong Bay and worst in Hansilpo. The highest mortality was observed $82\%$ in the waters off Saryangdo.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.179-187
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• 2018

In order to understand the flow of currents around Aphae Island and the surrounding Archipelago, the numerical model experiments on tidal currents and tide-induced residual currents were carried out. Dominant semidiurnal tidal currents have a reversing form and flow along the narrow channels of the archipelago. During periods of flood, currents flow from the west of Hwawon Peninsula to the archipelago to the northwest together with the currents flowing from the channels at Palgeum Island to Amtae Island and Amtae Island to Jeung Island. Ebb currents flow from the northwest archipelago to the channel of Amtae Island and Jeung Island as well as Amtae Island to Palgeum Island, further flowing south between Palgeum Island and Hwawon Peninsula. Flood currents are separated from east and west at the southern coast of Aphae Island, but flow south from both the west and east of Aphae Island to the channel found between Palgeum Island and Hwawon Peninsula at ebb. Flow speed is high between Amtae Island and Aphae Island where the flows meet and join. Lee wakes or topographical eddies are formed around the islands due to the high speed of the currents flowing along the narrow channel in the archipelago, manifesting as a tide-induced residual current. A weak cyclonic wake and anti-cyclonic eddy both exist at the west and northwestern coast of Aphae Island individually. The speed of the tide-induced residual current become slow on account of the wide littoral zone at exists around Aphae Island.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.4 no.4
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• pp.261-270
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• 1992

To investigate the flow patterns and diffusions in the Taean coastal waters of the eastern Yellow Sea, hydraulic and numerical experiments of tidal currents and diffusions of dye and cooling water were performed during spring tide along with field observations. Flow patterns obtained by the hydraulic and numerical experiments approximately coincide with those of the field observations. In the fold observations of tidal current, currents flow southwestward during the ebb tide, while currents flow northeastward during the flood tide. and the maximum velocity is 2.13 ㎧ toward WSW direction. The Eulerian diffusion coefficient estimated from field measmements of current is 7.82$\times$10$^{5}$ $\textrm{cm}^2$/s. Diffusion coefficients obtained from the area of dye plume in the model are given by the expression 0.18 $r^{4}$3/, and the coefficients have the range of 10$^{5}$ ~10$^{6}$ $\textrm{cm}^2$/s. These values are similar to the Eulerian diffusion coefficient estimated fram field measurements. Diffusion coefficients obtained in the hydraulic model are one to two orders higher than those obtained in the Onsan Bay in the eastern waters and two to three orders higher than those obtained in the Chinhae Bay in the southern waters of the Korean Peninsula. Diffusion patterns of cooling water by numerical experiments are similar to those of dye plume by hydraulic experiments. Both hydraulic and numerical experiment results of diffusions of dye plume and cooling water in the Taean coastal waters, have shown that the diffusion during the ebb tide is more prevalent than one during the flood tide.