• Atmosphere
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• v.21 no.4
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• pp.439-446
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• 2011

NCEP reanalysis data were analyzed in order to provide distribution of global wind resource and wind speed in the surface layer for the years 2000-2009. Wind speed at 10 m above ground level (AGL) was converted to wind speed at 80 m above the ground level using the power law. The global average 80 m wind speed shows a maximum value of $13ms^{-1}$ at the storm track region. High wind speed over the land exists in Tibet, Mongolia, Central North America, South Africa, Australia, and Argentina. Wind speed over the ocean increased with a large value in the South China Sea, Southeast Asia, East Sea of the Korea. Sea surface wind in Western Europe and Scandinavia are suitable for wind farm with a value of $7-8ms^{-1}$. Areas with great potential for wind farm are also found in Eastern and Western coastal region of North America. Sea surface wind in Southern Hemisphere shows larger values in the high latitude of South America, South Africa and Australia. The distribution of low-resolution reanalysis data represents general potential areas for wind power and can be used to provide information for high-resolution wind resource mapping.

• Water for future
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• v.21 no.2
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• pp.183-192
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• 1988

The previous two-dimensional non-linear tidal model of the East China Sea(Choi, 1980) has been further refined to resolve the flow over the ocntinental shelf in more detail. The mesh resolution of the present finite-difference grid system used is 4 minutes latitude by 5 minutes longitude over the entire shelf. The developed fine grid two-dimensional model was utilized to reproduce the $M_2$ tide and $M_4$ tide for the East China Sea contnental shelf. There is general agreement between the model results and the current observation made in the Eastern Yellow Sea, which supports the calculated tidal regime over the shelf. Some preliminary results on maximum bottom stress and tidally-induced residual current were also examined and discussed.

• Korean Journal of Ichthyology
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• v.26 no.2
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• pp.133-138
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• 2014

We investigated the spacial distribution and species composition of fish larvae during winter season (January 2013~March 2013) in Jinhae Bay, Korea. During the study period, a total of 12 larvae species belonging to 8 families were collected, and the dominant species were Pholis crassispina, Clupea pallasii, Liparis tanakae, Hexagrammos otakii. These four species accounted for 93% of the total number of individual collected. High density and species diversity occurred around Jam-do and eastern area of Chilcheon-do, suggesting that these areas are the main spawning ground of fish larvae in Jinhae Bay.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.2
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• pp.93-106
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• 2021

Changes in the fishing grounds for four drag-bagnet fisheries (large trawl, large pair trawl, large Danish seine and middle Danish seine) were investigated by year and sea-blocks in Korean waters. We used catch and effort data by sea-block (latitude × longitude: 30' × 30') of the National Institute of Fisheries Science (NIFS) and yearly fishing production statistics of the Korean statistic information service from 2008 to 2014. The main benthic habitat of fishing ground was sand and sandy mud material. The average swept areas for the four fisheries were 181.7 km², 606.4 km², 2,720.9 km² and 252.8 km², respectively. The main fishing ground was around Jeju Island and the eastern South Sea. The main fishing ground moved to the northern part of the South Sea during the study period due to a closure of fishing grounds and changes in the target species.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.4
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• pp.312-322
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• 2008

The age and growth of the sandfish, Arctoscopus japonicus were investigated from samples of the eastern sea danish seine and gill net fishery in the East Sea of Korea from February, 2004 to December, 2007. Ages were determined from annuli in otoliths and annuli were formed between December and February once a year. Also, the main spawning period was estimated to be between December and January, thus rings were considered to be annual marks. For the relationship between fork length and total weight, a multiplicative error structure was assumed because variability in growth increased as a function of the length. The relationship between fork length and total weight were $TW=0.0083FL^{3.01}(R^2=0.966)$ for female and $TW=0.0079FL^{3.04}(R^2=0.969)$ for male. The variability in growth was constant as a function of age, revealing an additive error structure. The von Bertalanffy growth parameters estimated by a non-linear method were $L_{\infty}=31.6cm$, K=0.266/year, $t_0=-0.835$ years for female and $L_{\infty}=27.7cm$, K=0.273/year, $t_0=-0.806$ years for male. Growth at age between male and female had a significant difference(P<0.001).

• 한국해양학회지
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• v.27 no.1
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• pp.1-10
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• 1992

The sea surface winds are computed over the adjacent seas of Korea from the twice-dayily weather maps for the ten-year period 1978-1987 by using the Cardone model. Monthly mean wind-stress and wind0stress curl are also calculated and given as maps. the computed surface winds are compared with observed one at the JMA (Japan Meteorological Agency) Buoy. and the results show a good consistency in speed and direction. In particular, the magnitude of mean wind-stress is turned out to be twice bigger than the previous results over the sea of Japan. Monthly distributions of wind-stress curl reveal that over the yellow sea by the longitudinal boundary of $120^{\circ}{\;}~{\;}125^{\circ}{\;}E$, the area of negative cur exists over the western part of the sea except summer season, while the positive sign of the curl prevails over the eastern part of the Yellow Sea. However, over the Sea of Japan, with two positive maxima at the northern part and near the Wonsan Bay, the positive curl in the northern half and the negative curl in the southern of the sea characterize the monthly mean distribution of the wind-stress curl.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.665-669
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• 2010

To confirm the distributon of finless porpoise, Neophocaena phocaenoides, in the South Sea of Korea, data on bycatch, stranding, and drifting of finless porpoises from 1999 to 2009 were used and a sighting survey was conducted from the R/V Tamgu No. 9 and 10 in June and November, 2009 and March, 2010. The total number of bycaught, stranded, and drifting finless porpoises was 607, with position being known for 186 of these. At the center of Yeosu, there were few position data on bycaught, stranded, and drifting finless porpoises, and data could not confirm the distribution of finless porpoises. Thus, there were limits on the usefulness of bycaught, stranded, and drifting data for confirming the distribution of finless porpoises. In the three sighting surveys, the sighting rate was highest at 0.231 ind./n.m. in the western South Sea in June, 2009. Sighting rate was less than 0.1 ind./n.m. in November, 2009 and March, 2010. This is likely to be due to seasonal migration in western South Sea. All sighting rates in the eastern South Sea were over 0.13 ind./n.m.. According to the results of the sighting survey, finless porpoises are distributed around the islands and inner bay along the path of the research vessel in the South Sea. There were numerous finless porpoises in the offshore areas of Mokpo, Yeosu, Tongyeong, Dadaepo, and Gaduk-do. This study will be utilized as part of a future abundance assessment of finless porpoise in the South Sea of Korea.

• Journal of the korean society of oceanography
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• v.37 no.3
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• pp.169-177
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• 2002

An eddy-resolving free-surface primitive-equation model with nonlinear terrain-following coordinates is established to study the exchange of water masses among the Asian marginal seas and their adjacent waters. A curvilinear coordinate system is used to generate the horizontal grid with a variable resolution for the regional oceans from $5^{\circ}$S to $45^{\circ}$N and $100^{\circ}$E to $155^{\circ}$E. The higher resolution region has about a 10 km by 10 km grid covering the complex geometry of the coastal marginal seas, while the lower resolution region has about a 30 km by 30 km grid covering the eastern Pacific. The model is initialized by the Levitus annual climitology and forced by the monthly mean air-sea fluxes of momentum, heat, and freshwater derived from the Comprehensive Ocean-Atmosphere Data Set. High-resolution and low-viscosity are identified as the key factors for a better representation of the exchange of waters through narrow straits and passages between the marginal seas and their adjacent waters. The dynamics of the loop currents and eddies in the South China Sea and Celebes Sea are examined in detail. It has found that the anticyclonic loop and detached eddies from the Kuroshio through the Luzon Strait play an important role in transporting warm and salty water into the South China Sea, while the cyclonic circulation of the Mindanao Current in the Celebes Sea plays a role in contributing cold water to the Indonesian throughflow. The deep undercurrent of the western Pacific is shown to provide fresher water to the South China Sea and Celebes Sea. These modeling results suggest that the exchange processes via the narrow straits and passages are of fundamental importance to the maintenance of water masses for the marginal sea region.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.5
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• pp.315-322
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• 2007

Kjellmaniella crassifalia Miyabe is one of the valuable seaweed crops cultured in the Korean coastal waters of the East Sea. Unfortunately recent environmental changes have adversely influenced its growth, prompting the need to develop techniques for species restoration. To obtatin biological information, the growth of the species was monitored for one year. The maximum blade length, $110{\pm}45cm$, was attained in July, and zoospores were released in November. The optimum culture conditions allowing juvenile sporophytes to grow to young blades consisted of $20{\mu}mol/m^2s\;at\;10^{\circ}C$ under which the blade length grew to $1,732.5{\pm}143.3{\mu}m$ in 42 days. Sporangial sori started to form in September, reaching 85% maturity in November and 89% maturity in December. Examining the growth of the species according to depth, the individuals growing at 5 meters grew the most, reaching a blade length of $75.9{\pm}18.9cm$ in August.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.28 no.1
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• pp.13-26
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• 2016

Sea water level variations are generally influenced by a variety of factors such as tides, meteorological forces, water temperature, salinity, wave, and topography, etc. Among non-tidal conditions, atmospheric pressure is one of the major factors causing water level changes. In the East Sea, due to small tidal range which is opposite to large tidal range of the Yellow Sea, it is difficult to predict water level changes using a numerical model, which consider tidal forcing only. This study focuses on the effects of atmospheric pressure variations on sea level predictions along the eastern coast of Korea. Telemac-2D model is simulated with the Inverted Barometer Effect(IBE), and then its results are analyzed. In comparison between observed data and predictions, the correlation of prediction with IBE and tide is better than that of tide-only case. Therefore, IBE is strongly suggested to be considered for the numerical simulations of sea level changes in the East Sea.