• Journal of the korean society of oceanography
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• v.34 no.3
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• pp.133-143
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• 1999

We carried out simultaneous and long-time observations of currents across the western channel of the Korea Strait during the period of May, 1994 to September, 1996 in order to understand the spatial and temporal variability of tidal and nontidal currents in the Strait. Results show that currents in the Strait are quite variable in space and time, and they largely consist of mean current and diurnal and semidiurnal tidal currents of about equal magnitudes. The mean currents include the Tsushima Current and the Korea Strait Undercurrent at the center of the channel. The former occupies the upper two-thirds and the latter the lower one-third of the water column. The semidiurnal and diurnal currents are largely rectilinear in the direction of NE-SW and their amplitude variation across the channel appears to be small. However, the diurnal currents at some locations show rotational characteristics with significant nontidal effects. The station close to the Korean coast leads the phase and the phase difference of the semidiurnal current across the channel appears to be less than half an hour while that of the diurnal current is over five hours.

• 한국해양학회지
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• v.28 no.1
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• pp.35-46
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• 1993

To delineate water properties and current patterns in the spawning area of walleye pollock, hydrographic cast and current meter data collected in Strait, Gulf of alaska, were analysed, three water masses are identified in Shelikof Strait. A small amount of cold and dilute water ($<{\;}3^{\circ}C{\;}and{\;}<{\;}31.5\textperthousand$) originates from the lower Cook Inlet and flows southwestward close to the Alaska Peninsula coast. One branch of alaska coastal Current which enters the strait from the northeast comprises the main body of the upper and middle layers of the strait, and flows toward the southwest. Estimation of geostrophic baroclinic currents reveals that comparatively fast flow exists in the surface over the deepest portion of the strait, and most water exits through the southwestern entrance between Semidi and chirikof Is. On the other hand, a relatively slow-moving warm and saline ($>{\;}5^{circ}C{\;}and{\;}>{\;}32\textperthousand$) of the southwestern entrance flows northeasterly, and occupies the bottom layer in Shelikof Strait.

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

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.13-17
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• 2006

Almost every day close passage or near miss events happens in south part of Istanbul Strait between the vessel runs in the local area and pass strait transit. The vessels run in the local area pass close bow or aft of transit vessel or come close and wait for transit vessel because of inexperienced or incompetent skipper or because of time limitation or failure in technical equipment or lack of technical equipment or old equipment. This close passages create profound dangers for the surroundings. By the this research has been aimed to point out mentioned dangers by the concrete as number. For this purpose has been utilized JMS Ship Handling Simulator which has been settled in ITU Maritime Faculty and Environmental Stress Model which has been built up and improved in Inoue Laboratory. Has been put in the senarios which been played during simulation implementations transferred to the numerical risk occured during passage of South Part of Istanbul Strait by the Environmental Stress Model . Thus so, the riskwhich Istanbul Strait face everyday has been expressed as numerical and concrete.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.1021-1032
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• 1997

Satellite-tracked drifters deployed in the East Sea since 1991 are used to study the Tsushima Current (TC). It is found that the TC is a steady current with a mean speed of 10 cm/s before it enters the East Sea. Only during the summer, the TC flows along Honshu Island with a mean speed of $30\~40\;cm/s$ and then exits through the Tsugaru Strait. In fall and winter, the TC does not follow the coast along Honshu Island but it enters into the interior of the East Sea before it reaches the Tsugaru Strait. The water that passes the West Channel of the Korea Strait mostly comes from the western East China Sea and spreads into the interior of the East Sea. It also forms the large eddies in the southern East Sea. The outflow through the Tsugaru Strait comes from the interior of the East Sea in all seasons except summer. The mean speed of the Tsugaru Strait outflow is about 60 cm/s. The largest current variability is found in the eastern central area of the East Sea, south of sub-polar front.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.1
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• pp.25-33
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• 2015

The Strait of Malacca is one of the most important fairways in the world and its traffic safety has direct effect on economic development of East Asian countries including China, Japan and Korea. Because of this reason, a safety analysis of the marine traffic in the strait has a great significance. In this paper, we analysed the statistic distribution of marine traffic in the Strait of Malacca based on the vessels' AIS data for 1 month by using the TOAIS and EasyFit programs. As the results of the analysis, it was found that the traffic distribution of this strait was different with normal distribution, which had been still widely used in marine traffic engineering field. Furthermore, with the traffic distribution analysis results, the traffic safety of the strait was also assessed by using the IWRAP model. The results showed that the highest level of risk were overtaking and crossing situations. Finally, we found that the highest risk of collision area in the Strait of Malacca was crossing area between the Strait of Malacca and the Port Klang fairway.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.2
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• pp.117-134
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• 1998

The study on the Assembling Mechanism of the Hairtail, Trichiurus lenpturus, at the Fishing Grounds of the Cheju Strait had been investigated by analyzing the relationship of the oceanographic conditions and the fishing ground of the Hairtail in the Cheju Strait. 1. The fishing grounds of the hairtail at the Cheju Strait are formed at the bottom of a high temperature of the tidal front at the coast. area of northern Cheju Island, the tip of the linguiform is high in salinity at the eastern and western entrances of Cheju Island, low salinity eddy on the surface and its surrounding front, various water masses in the Strait and coastal waters of the South Sea in Korea. 2. The fishing grounds of the Hairtail at the Cheju Strait begins with the sea surface temperature higher than $15^{\circ}C$ and the incoming of low salinity water now from the East China Sea. 3. Estimation of optimum temperature and salinity per season based upon analysis for relationship between temperature of water and salinity of the bottom layer and the catch is : 15.2~$16.4^{\circ}C$, 34.20~34.40${\textperthousand}$ in spring(June); 14.4~ $17.0^{\circ}C$, 33.70~34.30${\textperthousand}$ in summer(July~September); and 15.7~ $18.6^{\circ}C$, 33.70~34.50$\textperthousand$ in autumn(October~December). Hairtail are mostly caught at the Yellow Sea Warm Current and Tsushima Current with temperature over $14.5^{\circ}C$ and salinity over 33.70${\textperthousand}$ at the bottom layers of the Cheju Strait. 4. Considering the relationship between the amount of hairtail catch and the water temperature of bottom layer, when the bottom water being above $14.0^{\circ}C$ flowed into Cheju Strait through the western entrance of the strait in summer, the ca-h appears to have been abundant. In contrast, the catch has been poor when the temperature of such water was recorded to be below $13^{\circ}C$ Therefore, distribution patterns of water at the bottom layer can be used as a forecast index whether the catch of a certain year will be good or poor.

• Journal of Navigation and Port Research
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• v.34 no.9
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• pp.687-692
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• 2010

This study is to improve the marine traffic environment along the west coast of the Korean peninsular so as to prevent the traffic accidents of the dangerous cargo carriers. The most used routes of the vessels were investigated from GICOMS database and the questionnaire survey. Gwanjanghang Sudo strait and Maenggol Sudo strait were considered to have some potential risks to the vessels. In this study, the alternative routes were developed to substitute the current routes near Gwanjanghang Sudo strait and the new boundary line of The Traffic Prohibited Area for Tanker was suggested to contain the Maenggol Sudo strait.

• Journal of the Korean Institute of Navigation
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• v.8 no.1
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• pp.49-70
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• 1984

Spatial and temporal variations of hydrography and currents are investigated in the Southeastern Sea of Korea during October 1982. The distribution of the water mass of high salinity (>34.40${\textperthousand}$) and low dissolved oxygen concentration (<5.0ml/l) indicates that the Tsushima current flows northward as it passes the Western Channel of the Korea Strait. The cold water (<$6.0^{\circ}c$) with low salinity (<$34.20{\textperthousand}$) and high dissolved oxygen concentration (>6.0ml/l) reaches the bottom of the western channel of the Korea Strait after flowing southward leaning against the slope rather than following the deepest part of the Channel. Repeated sections in the Korea Strait show a remarkable change of hydrographic structure over a period of 4 days ; both warn and cold waters are intensified, particularly in the eastern part of the strait toward the Tsushima Island.

• Proceedings of the KSRS Conference
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• v.2
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• pp.943-945
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• 2006

The experiment on study of ambient nose generated by large-amplitude internal waves in Luzon Strait is analyzed. Simultaneous observations of internal waves and characteristics of ambient noise generated by them were carried out. Fast 50-m solitary internal wave propagated to the northwest direction with speed more than 3 m/s was observed. It was revealed an enhancing of ambient noise level (at frequency range 1-2 kHz) at a time of passing the face side of the solitary wave.