• Title/Summary/Keyword: coastal sea

Search Result 3,174, Processing Time 0.032 seconds

Dinoflagellate Cyst Assemblages in the Surface Sediments from the Northwestern East China Sea

  • Cho Hyun-Jin;Matsuoka Kazumi;Lee Joon-Baek;Moon Chang-Ho
    • Fisheries and Aquatic Sciences
    • /
    • v.4 no.3
    • /
    • pp.120-129
    • /
    • 2001
  • Thirty-six dinoflagellate cysts, representing 15 genera were identified in the surface sediments obtained from the northwestern East China Sea. Three cyst morphotypes found in this survey have not previously been described in the East China Sea and adjacent waters: Seleno­pemphix sp. 2, Selenopemphix sp. 3 and Trinovantedinium sp. 1. In the northwestern East China Sea, Operculodinium centrocarpum, Spiniferites bulloideus and ellipsoidal cysts of Alexandrium were commonly observed. Moreover, it was recognized that the ellipsoidal cysts of Alexandrium, whose motile cells of A tamarense and/or A catenella are responsible to paralytic shellfish poisoning, distributed not only restricted to the coastal areas but also to the offshore stations far from the Changjiang River mouth.

  • PDF

SST Effect upon Numerical Simulation of Atmospheric Dispersion (대기확산의 수치모의에서 SST 효과)

  • 이화운;원경미;조인숙
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.15 no.6
    • /
    • pp.767-777
    • /
    • 1999
  • In the coastal region air flow changes due to the abrupt change of surface temperature between land and sea. So a numerical simulation for atmospheric flow fields must be considered the correct fields of sea surface temperature(SST). In this study, we used variables such as latent heat flux, sensible heat flux, short and long wave radiation of ocean and atmosphere which exchanged across the sea surface between atmosphere and ocean model. We found that this consideration simulated the more precise SST fields by comparing with those of the observated results. Simulated horizontal SST differences in season were 2.5~4$^{\circ}C$. Therefore we simulated the more precise atmospheric flow fields and the movement and dispersion of the pollutants with the Lagrangian particle dispersion model. In the daytime dispersion pattern of the pollutants emitted from ship sources moved toward inland, in the night time moved toward sea by land/sea breeze criculation. But air pollutants dispersion can be affected by inland topography, especially Yangsan and coastal area because of nocturnal wind speed decrease.

  • PDF

Comparisons of Ocean Currents Observed from Drifters and TP/ERS in the East Sea

  • Lee, Dong-Kyu;Niiler, Pearn P.;Suk, Moon-Sik
    • Ocean and Polar Research
    • /
    • v.23 no.2
    • /
    • pp.133-139
    • /
    • 2001
  • Ocean currents estimated from sea height anomalies derived from inter-calibrated TP/ERS are compared with daily mean currents measured with satellite-tracked drifters. The correlation coefficient between the geostrophic current from TP/ERS and surface current at 15 m depth from drifter tracks was found to be about 0.5. Due to the limitation of satellite ground tracks, small scale eddies less than 80 km are poorly resolved from TP/ERS. One of the interesting results of this study is that coastal currents along the eastern coast of Korea were well reproduced from sea height anomalies when the coastal currents were developed in association with eddies near the South Korean coast. The eddy kinetic energy (EKE) estimated from drifters, TP/ERS, and a numerical model are also compared. The EKE estimated from drifters was about 22 % higher than EKE calculated from TP/ERS. The pattern of low EKE level in the northern basin and high EKE level in the southern East Sea is shown in the EKE estimates derived from both the drifters and TP/ERS.

  • PDF

Development of Fine-grid Numerical Tidal Models of the Yellow Sea and the East China Sea (세격자체계의 황해 및 동지나해 조석모형의 개발)

  • 최병호
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.2 no.4
    • /
    • pp.231-244
    • /
    • 1990
  • The objectives of this multiyear research are directed toward the investigation of mesoscale circulation dynamics in the Yellow Sea and the East China Sea. With the advent of Supercomputers and increasing necessity of resolving the flow with enough details, a hydrodynamic numerical model of the East China Sea has been developed with resolution of 1/15$^{\circ}$latitude by 1/12$^{\circ}$longitude covering the entire continental shelf. As a first step M$_2$tidal regime representing the domanant tidal conditions of the shelf was computed. Preliminary results are presented and discussions for further developments are presented.

  • PDF

Quantifying of the Persistent Periods of the Positive and Negative Sea Surface Temperature Anomalies at the Coastal Areas of the Korean Peninsula (한국연안 이상고수온과 저수온의 지속성 기간의 정량화)

  • 서영상;황재동;장이현;강용균
    • Journal of Environmental Science International
    • /
    • v.10 no.2
    • /
    • pp.167-171
    • /
    • 2001
  • The magnitudes of sea surface temperature (SST) anomalies at 13 coastal stations along the Korean peninsula in the summer and winter for the past 29years (1969-1997) are more larger than those in the spring and autumn. The periods of positive SST anomalies (negative SST anomalies) longer than 1$^{\circ}C$ were 75(74.5) months in the eastern coast of Korea, 47.8(51.6) months in the southern coast of Korea and 69.5(69.8) months in the western coast of Korea during the past 348 months (1969-1997). The predominant periods of the low-pass filtered monthly SST anomalies are 3 years or 13 months, even another predominant period is 24 months. The spatial variation of SST anomalies were confined by regional seas of the Korean peninsula, such as the East Sea, the South Sea and the West Sea itself.

  • PDF

Vulnerability Analyses of Wave Overtopping Inundation by Synthesized Typhoons with Sea-Level Rise (해수면 상승과 빈도 합성태풍이 고려된 월파범람 위험성 분석)

  • Kim, HyeonJeong;Suh, SeungWon
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.31 no.5
    • /
    • pp.253-264
    • /
    • 2019
  • Storm surges caused by a typhoon occur during the summer season, when the sea-level is higher than the annual average due to steric effect. In this study, we analyzed the sea-level pressure and tidal data collected in 1 h intervals at Incheon, Kunsan, Mokpo, Seogwipo stations on the Yellow Sea coast to analyze the summer season storm surge and wave overtopping. According to our analyses, the summer mean sea-level rise on the west and south coasts is approximately 20 cm and 15 to 20 cm higher than the annual mean sea-level rise. Changes in sea-level rise are closely related to changes in seasonal sea-level pressure, within the range of 1.58 to 1.73 cm/hPa. These correlated mechanisms generates a phase difference of one month or more. The 18.6 year long period tidal constituents indicate that in 2090, the amplitude of the $M_2$ basin peaks on the southwest coast. Therefore, there is a need to analyze the target year for global warming and sea-level rise in 2090. Wave overtopping was simulated considering annual mean sea-level rise, summer sea level rise, the combined effect of nodal factor variation, and 100-year frequency storm surge. As a result, flooding by wave overtopping occurs in the area of Suyong Bay, Busan. In 2090, overtopping discharges are more than doubled than those in Marine City by the recent typhoon Chaba. Adequate coastal design is needed to prepare for flood vulnerability.

A Study on Management of Foreign Seamen on Board Coastal & Offshore Fishing Boats (연근해어선에 승무하는 외국인 어선원의 관리방안)

  • Cha, Cheol-Pyo;Park, Jong-Un
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.23 no.3
    • /
    • pp.515-525
    • /
    • 2011
  • Due to changes in internal and external environment of coastal & offshore fishery such as decrease in coastal & offshore fishery resources, rising labor costs, rising gas prices, rising turnover rate of seamen, and intensified avoiding 4D types of business, the domestic seamen's avoidance of going to sea is being intensified. In order to solve the problems of domestic seamen shortage, coastal & offshore fishery businesses prefer to employ foreign seamen whose wages are relatively low, so employment of foreign seamen continues to increase. However, the foreign seamen system has the problems in selecting and managing seamen but these problems have been not adequately dealt with, so damages to fishery business continue to occur due to the seamen's deserting. The cases, in which foreigners who entered the country to take the sea in coastal & offshore fishing boats deserted their workplace, recorded 36.4% as of 2010. So in order to achieve the purpose of the foreign seamen system itself through rational management of foreign seamen, the exclusive organization to manage foreign seamen should be established and the system to rationally select foreign seamen who have experiences of fishery should be established. The utilization of foreign seamen during off season needs to be maximized by establishing the employment connection system for the management of foreign seamen and employment stabilization, and the exclusive organization for education of foreign seamen and the organization for nurturing domestic seamen need to be established and operated.

Assessment and Improvement of Ocean Physics for Coastal Erosion Projects (연안침식방지사업의 해양물리분야 평가실태 및 개선방안)

  • TAC, Daeho;OH, Hyuntaik
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.28 no.4
    • /
    • pp.947-956
    • /
    • 2016
  • This study analysed the documents of Sea Area Utilization Consultation of JongChun and ApHae located in West Coast of Korea and NaJeong located in East Coast of Korea in order to find out problems of site surveys and numerical simulations for coastal erosion projects of ocean physics, and suggested the improvement way to go. Current especially like wave-induced current is the one of the important external forces to handle coastal erosion but underestimated in the west coast. In case of east coast the various tests including wave-induced current were conducted but less efficient to find out the reasons of coastal erosion. The stiffness structure to protect coastal line like beach made the secondary erosion by using them without sufficient analysis for the erosion. In order to consult a Sea Area Utilization Consultation those are needed to review the scenarios for external forces such as wave and tidal currents, the site surveys for external forces, the net sediment analysis for years, the long periods of monitoring, and the guide line and revision of the rule for coastal erosion.

Marine Tourism Development Strategy of the South Sea through Sustainable Management of Coastal Environment

  • Yhang, Wii-Joo
    • Journal of Navigation and Port Research
    • /
    • v.30 no.4
    • /
    • pp.295-302
    • /
    • 2006
  • This study is to integratedly examine coastal management policy and marine tourism development project for Korean coasts, especially for the South Sea of high development pressure, presenting sustainable tourism development policies for the future. To do so, it is examined central government-level coastal development projects set up by the Ministry of Culture and Tourism, the Ministry of Maritime Affairs and Fisheries and the Ministry cf Construction and Transportation, setting the direction of south coastal management and tourism development at a level of national territory planning. The problems of coastal management first and then the problems of the South Coast Tourism Belt Project are analyzed in order to present political and administrative alternatives. To overcome such problems and make Korea a marine tourism base in East Asia, there is a need for re-recognition of the value of the project and its continuous push through cooperation between central and local governments. Also, under the presupposition of consensus building among local people and the sustainable development of environments, there should be are-recognition that the future cf Korean marine tourism in the 21st-century and the success of an inverted $\pi-axis$ national development depend on the South coastal Tourism Belt Development Project.

A Study on the Sea Level Variations in Korean Coastal Area (한국연안해역에서의 해면수위의 변동에 관한 연구)

  • 이경연;김동수;손창배;김창제
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.5 no.1
    • /
    • pp.19-27
    • /
    • 1999
  • This paper is to estimate the long and short term variations of mean sea level in Korean coastal waters by identifying interrelations among the mean sea level, atmospheric pressure and air temperature along the coast. For this, long-term tidal data observed at tidal and weather observation stations were brought into a statistical analysis. It was noted that, in a general sense, an inverse relationship exists between the sea level and the atmospheric pressure and a positive relationship between the sea level and air temperature, respectively. The maximum difference of monthly mean sea level was in the range of 21 to 25 cm at the eastern and southeastern coasts, meanwhile more than 30 cm being in both in southern and western coasts. It was also noted that mean sea level continues to rise in a long-term basis. Long-term variation of mean sea level trends to rise 0.10 ∼ 0.44 cm per year for each region. However, the long-term variation of mean sea level in the isolated islands shows a different trend, Ullngdo being 0.41 cm fall per year and Chejudo being 0.44 cm rise per year.

  • PDF