• Title/Summary/Keyword: Near sea

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Geostrophic Response of the Yellow Sea to Cyclone Passage

  • Oh, Im-Sang;Subbotina, Marina M.
    • Journal of the korean society of oceanography
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    • v.31 no.4
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    • pp.183-195
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    • 1996
  • A barotropic non-linear numerical model is used to study the response of the Yellow Sea to winter cyclone passage. Cyclones normally come from the outside of the western boundary, China, and pass the region eastward. The cyclone parameters used for the present study are the following: the intensity, i.e., the maximum wind speed of the cyclone; the effective radius corresponding to this maximum; and the translation speed. The equations of motion are integrated over the depth which is supposed to be a constant. The Gaussian function is used to define the stream function of the wind. The following results have been found. A northward current is generated by the frontal part of the cyclone near the western boundary. After the cyclone leaves the sea area, a southward current is generated by the rear part of the cyclone. After that, a northward current is generated once again due to the westward propagating Rossby waves. The response of the sea to the cyclone passage is strongly influenced by a steady current when the steady current and the current due to the cyclone wind are of the same order. The steady current diminishes the sea response and reduces the speed of the southward current, and enhances the northward current speed. The intensity and the translation speed of a cyclone also influence the flow pattern significantly.

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A study on the power plant system combined with PEM fuel cell and the wasted hydrogen from the sea water electrolyzer of nuclear power plants (원자력 발전소의 해수전해설비 폐수소를 활용한 PEM 연료전지 발전 시스템에 관한 연구)

  • Choi, Jongwon;Lee, Juhyung;Cha, Sukwon;Kim, Minsoo
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.124.2-124.2
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    • 2010
  • Generally, a coolant of the nuclear power plant is manufactured by electrolyzing the sea water near the plant for making the sodium hypochlorite(NaOCl), which is used for sterilizing the bacteria and the shellfishes sticking to the drains or the pumps at the outlet of the cooling system due to $8-10^{\circ}C$ warmer temperature than the inlet sea water. During manufacturing the sodium hypochlorite, the hydrogen with the high purity is also produced at the anode side of the electrolyzer. This paper describes a novel power plant system combined with the polymer electrolyte membrane(PEM) fuel cell, the wasted hydrogen from the sea water electrolyzer and the wasted heat of the nuclear power plant. The present status over the exhausted hydrogen at twenty nuclear power plants in Korea was investigated in this study, from which an available power generation is estimated. Furthermore, the economic feasibility of the PEM fuel cell power plant is also evaluated by a current regulations over the power production and exchange using a renewable energy shown in Korea Power Exchange(KRX).

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Tributyltin Compound in Sediments and Tissues of Oysters and Rock Shell in Gwangyang Bay, Korea

  • Shim, Won-Joon;Yim, Un-Hyuk;Kim, Nam-Sook;Hong, Sang-Hee;Oh, Jae-Ryoung
    • Korean Journal of Environmental Biology
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    • v.22
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    • pp.63-70
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    • 2004
  • Tributyltin (TBT) and its degradation products, dibutyltin (DBT) and monobutyltin (MBT) were quantitatively determined in surface sediments and two molluscan species, Pacific oyster (Crassostrea gigas) and rock shell (Thais ctavigera), from Gwangyang Bay, Korea. Butyltin compounds were detectable in almost all sediment and biota samples. Tributyltin concentrations in surface sediment ranged<2∼33 ng g$\^$-1/, which is at a lower end of TBT concentrations in industrialized bays in Korea. However, TBT levels in sediments were related to boating activities around the bay. In biota samples, TBT concentrations were in the range of 178∼2,458 ng g$\^$-1/ toy oyster and 47∼236 ng g$\^$-1/ for rock shell. Relatively high TBT concentrations in biota were found near wharves for fisherboats and harbor areas. About 90∼100% of the female T. clavigera displayed imposex, and relative penis length index of the imposexed-female was in the range of 20.9∼107.9%. Furthermore, TBT body residue had a significant positive relationship with degree of imposex in T. clavigera. Overall, TBT concentrations in Gwanyang Bay were much lower than other major bays in Korea.

Monthly Variation of Phytoplankton Composition and Water quality in Cupped Oyster Crassostrea gigas Culture Area in Iwon, Korea (이원면 굴, Crassostrea gigas 양식어장의 월별 식물플랑크톤 종조성 및 수질환경 변화)

  • Kim, Su Kyoung;Kim, Byeong Ho;Oh, Eun Kyoung;Song, Gi Chul;Park, Soung Yun;Hahn, Ki Yeon;Lim, Hyun Jeong
    • The Korean Journal of Malacology
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    • v.30 no.3
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    • pp.249-258
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    • 2014
  • Phytoplankton species composition and ecological index (diversity, evenness, richness and dominance) were analysed from April 2013 to March 2014 at 10 stations of cupped oyster, Crassostrea gigas culture area in Iwon coast, Korea. Seasonal and positional variation of phytoplankton standing crops, biomass, dominant species and water quality were distinctively different according to occasionally inflow of Iwon dam reservoired water. The composition of phytoplankton species were Bacillariophyceae 98, Dinophycease 22, Chlorophycease 13, Cyanophyceae 8, Silicofalgellate 4, Euglenophyceae 2, Cryptophyceae 1 species. The most dominant species was Bacillariophyceae as 64.0%. The highest biomass of phytoplankton recorded in September as $40,910{\times}10^3$ cell/L at the station 1, near from inland water inflow area. Ecological indices (diversity, richness, evenness, and dominance index), used for structural change of phytoplankton community and water quality (temperature, dissolved oxygen, salinity) showed difference of spatiotemporal property also.

Occurrence of Eggs and Larvae of Blackfin Flounder Glyptocephalus stelleri (Pleuronectidae, Pisces) off Wangdol-cho, East Sea (동해 왕돌초 주변해역에서 기름가자미 Glyptocephalus stelleri (가자미과, 어상강) 어란과 자어 출현)

  • Lee, Hae Won;Lee, Soo Jeong;Yang, Jae Hyung;Lee, Jae Bong;Cha, Hyung Kee;Kim, Jin-Koo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.5
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    • pp.654-658
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    • 2014
  • We report the first identification of a spawning ground of the blackfin flounder Glyptocephlaus stelleri near the Wangdol-cho sea mountains, located in the southern East Sea. Eggs and larval fish of G. stelleri were collected during April and June, 2014, when an abundance of eggs was found in the southern area of Wangdol-cho. Our findings suggest that G. stelleri prefers to spawn in the vicinity of the off-shore sea mountains, where the temperature is between 10 and $12^{\circ}C$ and the water depth is 100 m, rather than inshore.

MULTISENSOR SATELLITE MONITORING OF OIL POLLUTION IN NORTHEASTERN COASTAL ZONE OF THE BLACK SEA

  • Shcherbak, Svetlana;Lavrova, Olga;Mytyagina, Marina;Bocharova, Tatiana;Krovotyntsev, Vladimir;Ostrovskiy, Alexander
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.989-992
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    • 2006
  • The new approach to the problem of oil spill detection consisting in combined use of all available quasiconcurrent satellite information (AVHRR NOAA, TOPEX/Poseidon, Jason-1, MODIS Terra/Aqua, QuikSCAT) is suggested. We present the results of the application of the proposed approach to the operational monitoring of seawater condition and pollution in the coastal zone of northeastern Black Sea conducted in 2006. This monitoring is based on daily receiving, processing and analysis of data different in nature (microwave radar images, optical and infrared data), resolution and surface coverage. These data allow us to retrieve information on seawater pollution, sea surface and air-sea boundary layer conditions, seawater temperature and suspended matter distributions, chlorophyll a concentration, mesoscale water dynamics, near-surface wind and surface wave fields. The focus is on coastal seawater circulation mechanisms and their impact on the evolution of pollutants.

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Comparison of chlorophyll concentration in the Bay of Bengal and the Arabian Sea using IRS-P4 Ocean Color Monitor, and MODIS Aqua

  • Chaturvedi, Prashant;Prasad, Anup K.;Singh, Ramesh P.
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.487-490
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    • 2006
  • Ocean Color Monitor (OCM) onboard the Indian Remote Sensing Satellite IRS-P4 has been used to retrieve chlorophyll concentration in the Bay of Bengal and the Arabian Sea using a bio-optical algorithm. Cloud masking and atmospheric corrections have been performed before applying mapping function to derive chlorophyll concentration from IRS-P4 OCM data. We have retrieved chlorophyll concentration from OCM, and MODIS during the summer and winter season along the eastern and western coast of India at every 1 degree latitude at increasing distance (25, 50, 100, 150 and 200km) away from the coast as well as near river mouths for the period 2000-2003. We have also studied spatial and temporal dynamics of monthly MODIS Aqua (for period July 2002-April 2004). The seasonal dynamics of chlorophyll concentration over the Bay of Bengal and the Arabian Sea have been discussed using OCM and MODIS for both the coastal region and the open sea.

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Tracking the Movement and Distribution of Green Tides on the Yellow Sea in 2015 Based on GOCI and Landsat Images

  • Min, Seung-Hwan;Oh, Hyun-Ju;Hwang, Jae-Dong;Suh, Young-Sang;Park, Mi-Ok;Shin, Ji-Sun;Kim, Wonkook
    • Korean Journal of Remote Sensing
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    • v.33 no.1
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    • pp.97-109
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    • 2017
  • Green tides that developed along the coast of China in 2015 were detected and tracked using vegetation indices from GOCI and Landsat images. Green tides first appeared near the Jiangsu Province on May 14 before increasing in size and number and moving northward to the Shandong Peninsula in mid-June. Typhoon Cham-hom passed through the Yellow Sea on July 12, significantly decreasing the algal population. An algae patch moved east toward Korea and on June 18 and July 4, several masses were found between the southwestern shores of Korea and Jeju Island. The floating masses found in Korean waters were concentrated at the boundary of the open sea and the Jindo cold pool, a phenomenon also observed at the boundary of coastal and offshore waters in China. Sea surface temperatures, derived from NOAA SST data, were found to play a role in generation of the green tides.

A Stratification/Mixing Model of the Yellow Sea and the East China Sea (황해(黃海) 및 동지나해(東支那海)의 성층(成層)혼합·(混合)모델)

  • Choi, Byung Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.4 no.2
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    • pp.125-132
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    • 1984
  • A simple stratification/mixing model has been developed for shelf waters of the Yellow Sea and the East China Sea. The results are summarized in the form of maps of stratification parameter which utilized the estimates of tidal dissipation from non-linear two-dimensional tidal model of the region. Ultimate aim of this study is to evaluate the applicability of the tidal mixing criteria to the Yellow Sea especially for the offshore region near Taean Peninsula in the west coast of Korea using hydrographic data and computed stratification parameter.

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Distribution and Circulation of Autumn Low-salinity Water in the East Sea (동해의 가을철 저염수 분포 및 유동)

  • Lee, Dong-Kyu;Lee, Jae Chul
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.50 no.2
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    • pp.207-218
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    • 2017
  • Seawater with salinity of 32.5 psu or less is observed in the southern Japan/East Sea (JES) every autumn. It is confined to a surface layer 30-45 m in depth that expands to cover the entire JES in October. Two sources of "autumn low-salinity water" have been identified from historical hydrographic data in the western JES: East China Sea (ECS) water mixed with fresh water discharge from the Yangtze River (Changjiang) and seawater diluted with melted sea ice in the northern JES. Low-salinity water inflow from the ECS begins in June and reaches its peak in September. Low-salinity water from the northern JES expands southward along the coast, and its horizontal distribution varies among years. A rare observational study of the entire JES in October 1969 indicated that water with salinity less than 33.0 psu covered the southwestern JES; the lowest salinity water was found near the Ulleung Basin. In October 1995, the vertical distribution of salinity observed in a meridional section revealed that water with salinity of 33.6 psu or less was present in the area north of the subpolar front.