• Journal of the Korean Society of Marine Environment & Safety
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• v.10 no.1 s.20
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• pp.35-40
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• 2004

Ship can not sail without water. Ships sail along different routes with different natural conditions. Thus ships sailing at different sea areas have their respective characteristics. The northern sea area and the southern one of China have different characteristics, that is to song, the sea in the northern area is shallow and that in the southern area is deep, Chinese ships developed into different types in order to adapt to this.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.973-976
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• 2013

We observed the vertical distribution and feeding ecology of the Mirror dory, Zenopsis nebulosa, in the Southern Sea of Korea from 2009 to 2013 using an otter trawl. The total length of captured individuals ranged from 11 to 48 cm. Individuals captured at greater depths were significantly larger than those from shallower sites. Fish abundance was significantly related to depth and temperature. We found that 89% of the total catch was obtained at depths between 80 and 140 meters. Prey organisms, including fish, crustaceans, and cephalopods, were found in Z. nebulosa stomachs. Fishes were the main prey items for all size groups. Cephalopods were consumed by individuals > 25 cm in length. Our findings suggested that the vertical distribution of Z. nebulosa varied with depth and temperature, and that the fish are carnivores.

• 한국해양학회지
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• v.27 no.2
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• pp.123-136
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• 1992

As a result of faunal analysis on 50 bottom samples bearing a total of 183 species of the Recent benthonic foraminifers from the West and South Sea of korea, five bioassociations (groups of species) and five biotopes (groups of samples) were discriminated. From the areal distribution of biotopes in combination with bioassociations and the available ecological data of foraminiferal species, five biofacies are recognized: (1) Southern Inner Shelf Biofacies; (2) Southern Coast Biofacies; (3) Northern Middle Shelf Biofacies; (4) Central Middle Shelf Biofacies; and (5) Southern Outer Shelf and Upper Slope Biofacies. The biofacies are defined by a group of sampling stations containing a diagnostic species association and can be related to the major current pasterns and water masses in the West and South Sea of Korea: Southern Inner Shelf Biofacies is related to the Coastal Waters and drainage from China; Southern Coast Biofacies is related to the Coastal Waters and drainage from Korea; Northern Middle Shelf Biofacies is related to the Coastal Waters and Yellow Sea Cold Water, Central Middle Shelf Biofacies is related to the Yellow Sea Warm Current; and Southern Outer Shelf and Upper Slope Biofacies is related to the Tsushima Warm Current.

• Ocean and Polar Research
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• v.29 no.1
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• pp.1-8
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• 2007

A series of long chain unsaturated ketone (alkenone) was identified in the particulate organic matter sampled from surface water of the eastern South Sea, Korea. The seawater temperature based on the $C_{37}$ alkenone was calculated by using several different equations of unsaturation index(${U^{K'}}_{37}$), compared with in situ CTD temperature. Among the previously reported equations, the equation(0.044T-0.204) which was proposed by Sawada et al.(1996) seems to be the most useful for the calculation of $C_{37}$ alkenone temperature, showing average $0.51^{\circ}C$ difference between ${U^{K'}}_{37}$ temperature and in situ CTD temperature. This result suggest that alkenone should be a useful molecular biomarker for reconstructing paleo-environmental change in the South and East Sea, Korea. However, it is required to establish more reliable equation for the calculation of $C_{37}$ alkenone temperature.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.177-184
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• 2003

Numerical simulation on marine wind and sea surface elevation was carried out using both three-dimensional hydrostatic and non-hydrostatic models and a simple oceanic model from 0900 LST, August 13 to 0900 LST, August 15, 1995. As daytime easterly meso-scale sea-breeze from the eastern sea penetrates Kangnung city in the center part as basin and goes up along the slope of Mt. Taegullyang in the west, it confronts synoptic-scale westerly wind blowing over the top of the mountain at the mid of the eastern slope and then the resultant wind produces an upper level westerly return flow toward the East Sea. In a narrow band of weak surface wind within 10km of the coastal sea, wind stress is generally small, less than l${\times}$10E-2 Pa and it reaches 2 ${\times}$ 10E-2 Pa to the 35 km. Positive wind stress curl of 15 $\times$ 10E-5Pa $m^{-1}$ still exists in the same band and corresponds to the ascent of 70 em from the sea level. This is due to the generation of northerly wind driven current with a speed of 11 m $S^{-1}$ along the coast under the influence of south-easterly wind and makes an intrusion of warm waters from the southern sea into the northern coast, such as the East Korea Warm Current. On the other hand, even if nighttime downslope windstorm of 14m/s associated with both mountain wind and land-breeze produces the development of internal gravity waves with a hydraulic jump motion of air near the coastal inland surface, the surface wind in the coastal sea is relatively moderate south-westerly wind, resulting in moderate wind stress. Negative wind stress curl in the coast causes the subsidence of the sea surface of 15 em along the coast and south-westerly coastal surface wind drives alongshore south-easterly wind driven current, opposite to the daytime one. Then, it causes the intrusion of cold waters like the North Korea Cold Current in the northern coastal sea into the narrow band of the southern coastal sea. However, the band of positive wind stress curl at the distance of 30km away from the coast toward further offshore area can also cause the uprising of sea waters and the intrusion of warm waters from the southern sea toward the northern sea (northerly wind driven current), resulting in a counter-clockwise wind driven current. These clockwise and counter-clockwise currents much induce the formation of low clouds containing fog and drizzle in the coastal region.

• Journal of the korean society of oceanography
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• v.32 no.3
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• pp.128-137
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• 1997

This study presents results from a detailed sedimentological investigation of surface sediments obtained from the Korea Strait region, the southern part of the East Sea (Sea of Japan). The distribution of different types of bottom sediments is controlled by the recent fine-grained sediment transport and deposition combined with the lowerings of sea level during the last glacial period, forming a diverse mixture of organic-rich fine-grained and shelly coarse-grained sediments. In comparison to high organic concentration of fine-grained sediments in the inner continental shelf and slope areas, the shell-rich coarse-grained sediments on the outer shelf are discernible being further modified. These coarse-grained sediments are confirmed as relict resulting from the sediment dynamics during the lower sea levels of the last glacial period. Clay mineral distribution of the fine-grained sediments gives information about the transport mechanism. Presence of present-day current system (the Tsushima Warm Current) is most probable source for the fine-grained particles into the open East Sea from the East China Sea, indicating that Holocene sediment dynamics may be used to explain the observed distribution of surface coarse-grained shell-rich sediments.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.27 no.1
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• pp.41-55
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• 1991

A study was done to investigate characteristics of the land and sea breeze over Cheju island on the basis of surface meteorological data collected from 1977 to 1986. The results are summarized as follows: The frequency of the land and sea breze was highest in August followed by September, October, May and November in descending order. This indicates that the frequency of the land and sea breeze is higher in fall than in spring, and lowest in winter. The sea breeze began much earlier than any other regions of Korea all the year round, and it began about 30 minutes earlier and ended one hour later in the northern coast than in the southern coast of Cheju island. Meanwhile, the land breeze began about one hour earlier in the southern coast than in the northern coast and ended almost at the same time in both coasts. The annual mean duration of the sea breeze was about one hour longer in the northern coast than in the southern coast, but the land breeze showed an opposite trend. The duration of the sea breeze was longer in summer than in winter and again the land breeze was opposite. Transition period from the sea to the land breeze was relatively long in summer and shout in winter, but transition period from the land to the sea breeze was not different between seasons. The time for a maximum velocity of the sea breeze came earlier in the southern coast than in the northern coast, but that of the land breeze came almost at the same time in both coasts with no seasonal variations. Monthly mean maximum velocity of the sea breeze was greater than that of the land breeze.

• Ocean and Polar Research
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• v.26 no.1
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• pp.65-75
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• 2004

In order to understand the water masses and their distribution in the eastern Yellow Sea from winter to spring, a cluster analysis was applied to the temperature and salinity data of Korea Oceanographic Data Center from 1970 to 1990. From December to April, Yellow Sea Cold Water (YSCW) dominates the eastern Yellow Sea, whereas Eastern Yellow Sea Mixed Water (MW) and Yellow Sea Warm Water (YSWW) are found in the southern part of the eastern Yellow Sea. MW appears at the frontal region around $34^{\circ}N$ between YSCW in the north and YSWW in the south. On the other hand, Tshushima Warm Water (TWW) is found around Jeju Island and the South Sea of Korea. These water masses are relatively well-mixed throughout the water column due to the winter monsoon. However, the water column begins to be stratified in spring due to increased solar heating, the diminishing winds and fresh water discharge, and the water masses in June may be separated into surface, intermediate and bottom layers of the water column. YSWW advances northwestward from December to February and retreats southeastward from February to April. This suggests a periodic movement of water masses in the southern part of the eastern Yellow Sea from winter to spring. YSWW may continue to move eastward with the prevailing eastward current to the South Sea from April to June. Also, the front relaxes in June, but the mixed water advances to the north, increasing salinity. The salinity is also higher in the nearshore region than offshore. This indicates an influx of oceanic water to the north in the nearshore region of the eastern Yellow Sea in spring in the form of mixed water.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.05a
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• pp.83-84
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• 2004

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.4
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• pp.461-477
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• 2022

We investigated the community structure and performed detailed characterization of fish larvae assemblages collected from the southern coast of Korea in the spring and summer of 2021. The total abundance of fish larvae varied from 193.6 to 1,915.6 ind. 10 m^-3. The species were distributed across 10 orders with 23 families, and 41 taxa. The dominant taxa were Gobiidae spp., Engraulis japonicus, Nibea albiflora, Sebastiscus spp., Callionymus valenciennei, Pennahia argentata, Sebastes thompsoni, Parablennius yatabei, and Platycephalus indicus. Engraulis japonicus individuals were collected from April to August and their presence contributed greatly to the total abundance of fish larvae. The total number and abundance of species peaked in early summer and the Shannon-Weaver index was in the range 0.11-1.49. Redundancy analyses revealed that the major environmental factors affecting the fish larvae assemblage differed according to the dominant taxa. Water temperature, zooplankton density, and Paracalanus parvus s. l. density were the key factors affecting the spatial and temporal distribution of fish larvae in the southern coast of Korea in spring and summer.