• Ocean and Polar Research
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• v.32 no.3
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• pp.267-268
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• 2010

Many countries has been interested in studying the East Sea to look ahead into the world oceans' future, since the East Sea has been known as a miniature ocean. In this respect, PICES decided the East Asian Seas Time-series (EAST) studies, and the East Sea as the first subject (EAST-I). Since 2006 Ministry of Land, Transport & Maritime Affairs, Korea has supported the Korean EAST-I program. Through the Korean EAST-I program, 44 research papers were published in various scientific journals. This special issue contains 6 research articles including results from the interdisciplinary observation in the summer, 2008. Those articles cover the entire East Sea from the Korea Strait to the Japan Basin, and also cover the studies of the euphotic layer to the bottom sediment. MLTM and KIMST have provided full support to EAST-I program. KHOA carried out the joint cruises in the Ulleung Basin. Those are deeply appreciated. Finally, we would like to express our gratitude to the editorial board of Ocean & Polar Research.

• Journal of the korean society of oceanography
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• v.31 no.3
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• pp.123-133
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• 1996

We describe here the shallow water tides in the seas around Korea, obtained from a nonlinear barotropic model of tides in a domain encompassing the Yellow Sea, the East China Sea and the East Sea (Sea of Japan). As expected, the shallow water tides are large in the shallow marginal areas around the Yellow Sea, with the M4 tide reaching amplitudes as high as 10 cm near the Korean coast, and quite small in the East Sea. However, we also find that the regions east of the Yangtze River ($126^{\circ}E,$ $30^{\circ}N$) in the East China Sea also sustain large shallow water tides, with $M_{4}$, amplitudes reaching 5 cm. Such large shallow water tides are an important component of altimeter-measured sea levels and should not be ignored in any altimetric analyses of the Yellow Sea and the East China Sea. This study also highlights the desirability of very high resolution models to derive accurate shallow water tides in coastal regions.

• Journal of Environmental Science International
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• v.12 no.3
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• pp.257-263
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• 2003

Oceanographic features around Korean waters related to the global change were studied by analysis of the longterm variation of water temperature, dissolved oxygen, sea level of the surface layer with 1$^{\circ}C$ temperature, spatial position of the subpolar front in the East Sea/Japan Sea (the East sea hereafter) and the Wolf Sunspot Number. With the global warming, the temperature of Korean waters has been increased 0.5∼1.0$^{\circ}C$ for 33years (1968∼2000). In case of the dissolved oxygen in the East Sea has been decreased 0.46$m\ell$/$\ell$. Year to year vertical fluctuations of the monthly anomalies of the surface layer with 1$^{\circ}C$water in the East Sea have predominant periods with 15years as the longterm variation of Arctic climate, 12 and 18years as the El Nino-Southern Oscillation. Spatial position of the subpolar front in the East Sea moved to northern part of the sea from the southern part of the sea with the increasing sea surface temperature. The relationship between the number of Wolf Sunspot and the anomalies of sea surface temperature was very closer after the late of 1980s than those before the early of 1980s in Korean waters.

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.279-300
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• 1992

The Korean marine hydrioid fauna identified up to data consists of 120 species of 55 genera in 17 families. Of which Abientiunaria filicula (Ellis and Solander, 1786) is new to the Korean fauna, and the dominant species of hydroids in Korean water is Sertularella miurensis Stechow, 1921 which is collected from 33 points of 96 localities. The coastal waters of Korea are divided into four regions : the East Sea, the South Sea, the Yellow sea and the Chejudo. Concerning the total number of species occured in each region, 43 species in the East Sea, 52 species in the Yellow Sea, 73 species in the South Sea and 83 species in the Chejudo and its vicinity. From the results above described it can be salid that the Chejudo region shows the most diversity of the Korea hydroids. The community coefficient of the East Sea-the Yellow Sea is 0.444, that of the East Sea-the South Sea 0.553, that of the East Sea-Chejudo 0.519, that of the Yellow Sea-the Sea 0.682, that of the Yellow Sea-the Chejudo 0.533 and that of the South Sea-the Chejudo 0.642. So that the zoogeographical relatinship between the Yellow Sea and the South Sea is the highest and between the East Sea and the Yellow Sea is the lowest on the hydroids distribution.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.4 s.111
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• pp.33-44
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• 2005

In order to reveal the geographical landscape's features of the East Sea-gateway(東海口), which has existed only in the era of Shilla as unique east path, we have carried out analysis of the old maps(邑誌圖) and satellite imagery, and geographical features analysis in the application of digital maps, and the result is as follows. 1. Analysis of materials from the Chosun dynasty describes landscapes called sea gates(海口) (note that this should not be capitalized); a place where the river meets the sea and the sea comes far into the land. Sea gate landscapes may have an island, but this is not a prerequisite. 2. According to the satellite imagery, the capital city of Shilla Dynasty had five passages. four or them are broad corridors, but one of them is narrow. The east side of the capital city is blocked by mountains and there was an important path which leads into the East Sea. 3. According to the cross section of the mountains, there is the only rule East-path. There was no alternative way. There was only one way-out to the east side from the capital city. This is the unique path which reaches a length of 28km. Judging from this, it seems that this path was called the East Sea-gateway. 4. The landscape of the East Sea-gateway was shaped like the letter 'V' and reached to the landscape of the sea gate. However, the route was blocked - part by the mountains, and also the part in the crisis of loss of path-landscape which has lost its own character of closure as several valleys are merged together.

• Ocean and Polar Research
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• v.29 no.1
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• pp.9-31
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• 2007

Most seismic sea waves in the East Sea originate from earthquakes occurring near the Japanese west coast. While the waves propagate in the East Sea, they are deformed by refraction, diffraction and scattering. Though the Boussinesq equation is most applicable for such wave phenomena, it was not used in numerical modelling of seismic sea waves in the East Sea. To examine characteristics of seismic sea waves in the East Sea, numerical models based on the Boussinesq equation are established and used to simulate recent tsunamis. By considering Ursell parameter and Kajiura parameter, it is proved that Boussinesq equation is a proper equation for seismic sea waves in the East Sea. Two models based on the Boussinesq equation and linear wave equation are executed with the same initial conditions and grid size ($1min{\times}1min$), and the results are compared in various respects. The Boussinesq equation model produced better results than the linear model in respect to wave propagation and concentration of wave energy. It is also certified that the Boussinesq equation model can be used for operational purpose if it is optimized. Another Boussinesq equation model whose grid size is $40sec{\times}30sec$ is set up to simulate the 1983 and 1993 tsunamis. As the result of simulation, new propagation charts of 2 seismic sea waves focused on the Korean east coast are proposed. Even though the 1983 and 1993 tsunamis started at different areas, the propagation paths near the Korean east coast are similar and they can be distinguished into 4 paths. Among these, total energy and propagating time of the waves passing over North Korea Plateau(NKP) and South Korea Plateau(SKP) determine wave height at the Korean east coast. In case of the 1993 tsunami, the wave passing over NKP has more energy than the wave over SKP. In case of the 1983 tsunami, the huge energy of the wave passing over SKP brought about great maximum wave heights at Mukho and Imwon. The Boussinesq equation model established in this study is more useful for simulation of seismic sea waves near the Korean east coast than it is the Japanese coast. To improve understanding of seismic sea waves in shallow water, a coastal area model based on the Boussinesq equation is also required.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.401-414
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• 2012

Distribution pattern and fishing conditions of sandfish, Arctoscopus japonicus in the East Sae were explored using catch and catch per unit effort (CPUE) by eastern sea Danish seine and coastal gill net fisheries from 2004 to 2008. A. japonicus was one of major target species for the eastern sea Danish seine and coastal gill net fisheries in the East Sea, which were caught from April to October for the eastern Danish seine, and from October to December for the coastal gill net, respectively. In recent, the distribution and centroid of fishing ground moved northward, as seawater temperature increased. The species spawned in the coastal areas of Gangwon, northern East Sea, during winter, started to move to deeper water after spawning from spring, extended widely from Gangwon to Ulsan, southern East Sea, during summer, and migrated back to the spawning ground off Gangwon during autumn.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.320-328
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• 2007

Maturation and spawning of the Pacific cod, Gadus macrocephalus was investigated based on the samples captured in East Sea of Korea from April 2006 to July 2007. Gonadosomatic index began to increase in November, and reached maximum between December and January. After spawning it began to decrease from March. Reproductive season was estimated to November-February, with peak in January. Fecundity was proportional to the size of the female, with the clutch size varying from 753,985 eggs in the smallest female(TL＝58.6cm) to 9,311,520 eggs in the largest(TL＝101.0cm). Size at 50% sexual maturity(TL50%) determined from mature females was 56.3cm of TL. Annual reproductive cycles of this species could be divided into six successive stages; immature stage(March-September), nucleolus stage(September-October), yolk vesicle stage(October-November), vitellogenic stage (November-December), ripe stage and spent stage(December-February).

• Journal of the Korean earth science society
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• v.39 no.1
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• pp.1-22
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• 2018

Eight different data sets are examined in order to gain insight into the surface heat flux traits of the East Asian marginal seas. In the case of solar radiation of the East Sea (Japan Sea), Coordinated Ocean-ice Reference Experiments ver. 2 (CORE2) and the Objectively Analyzed Air-Sea Fluxes (OAFlux) are similar to the observed data at meteorological stations. A combination is sought by averaging these as well as the Climate Forecast System Reanalysis (CFSR) and the National Centers for Environmental Prediction (NCEP)-1 data to acquire more accurate surface heat flux for the East Asian marginal seas. According to the Combination Data, the annual averages of net heat flux of the East Sea, Yellow Sea, and East China Sea are -61.84, -22.42, and $-97.54Wm^{-2}$, respectively. The Kuroshio area to the south of Japan and the southern East Sea were found to have the largest upward annual mean net heat flux during winter, at -460- -300 and at $-370--300Wm^{-2}$, respectively. The long-term fluctuation (1984-2004) of the net heat flux shows a trend of increasing transport of heat from the ocean into the atmosphere throughout the study area.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.165-170
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• 2003

A significant surface net heat loss appears around the Kuroshio and the Tsushima Warm Current regions. The area where the surface heat loss occurs should require heat to be supplied by the current to maintain the long-term annual heat balance. Oceanic heat advection in these regions plays an important role in the heat budget. The spatial distribution of the heat supply by the Tsushima Warm Current near the surface was examined by calculating the horizontal heat supply in the surface layer of the East/Japan Sea, directly from historical sea surface temperature and current data. We have also found a simple estimation of the effective vertical scale of heat supply by the current to compensate net heat loss using the heat supplied by the current in the surface 10m layer. The heat supplied by the current for the annual heat balance was large in the Korea/Tsushima Strait and along the Japanese Coast, and was small in the northwestern part of the East/Japan Sea. The amount of heat supplied by the current was large in the northwestern part and small in the southeastern part of the East/Japan Sea. These features suggest that the heat supplied by the Tsushima Warm Current is restricted to near the surface around the northeastern part and extends to a deeper layer around the southeastern part of the East/Japan Sea.