• Title/Summary/Keyword: coastal sea

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The Marine Environment and Dinoflagellates Cysts in the Southwestern Sea of Korea (한국남서해역의 해양환경과 와편모조류 시스트 분포 특성)

  • Park, Jong-Sick;Yoon, Yang-Ho;Noh, Il-Hyeon;Soh, Ho-Young;Shin, Hyeon-Ho
    • ALGAE
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    • v.23 no.2
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    • pp.135-140
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    • 2008
  • A field survey for dinoflagellate cysts was carried out from May 2000 to November 2002 for the Southwest Sea of Korea. A total dinoflagellate cysts identified were 33 species, which belonged to 17 genera, 31 species, and 2 unidentified species. A cysts density were 16-1,501 cysts-gdry$^{-1}$. The dominant species of dinoflagellate cysts in the Southwestern Sea of Korea were Spiniferites bulloideus and Scrippsiella trochoidea, which are autotrophic species. To investigate the environmental characteristics of the Southwestern Sea of Korea using the dinoflagellate cysts, a principal component analysis (PCA) was conducted using the data collected from a total of 51 stations. From the score distribution map by the PCA, the Southwestern Sea of Korea was largely divided into three regions according to the first primary component and the second primary component. In other words, Group 1 was the western sea area of Mokpo and Jindo, Group 2 was the outer sea area of the South Sea, and Group 3 was the coastal areas of the South Sea around the Archipelago. It was found that this division of sea area was influenced by effects of the sea environment of the coastal areas of Korea. The coastal areas of Mokpo and Jindo that belong to Group 1 were affected by the cold Yellow Sea water. The outer sea area of the central parts of the South Sea that belong to Group 2, which is the boundary between the Southern coastal water of Korea and the Tsushima warm water, was subject to the formation of temperature fronts throughout the year, while Group 3 was affected by the coastal waters of Korea. It was also found that this division was in close relationship with the distribution of sediment facies in the bottom layer. From the above results, the environmental factors that influence the cyst distribution in he Southwestern Sea of Korea were found to include the eutrophication status of the sea area, the physical characteristics of the sea environment such as the flow of sea current and fronts, the sediment facies in the bottom layer, and the appearance volume of motile cells.

Characteristics of Atmospheric Circulation in Sokcho Coast (속초연안에서 대기순환의 특성)

  • Choi Hyo
    • Journal of Environmental Science International
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    • v.14 no.1
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    • pp.41-51
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    • 2005
  • Using three-dimensional non-hydrostatical numerical model with one way double nesting technique, atmo­spheric circulation in the mountainous coastal region in summer was investigated from August 13 through 15, 1995. During the day, synoptic westerly wind blows over Mt. Mishrung in the west of a coastal city, Sokcho toward the East Sea, while simultaneously, easterly upslope wind combined with both valley wind from plain (coast) toward mountain and sea-breeze from sea toward inland coast blows toward the top of the mountain. Two different directional wind systems confront each other in the mid of eastern slope of the mountain and the upslope wind goes up to the height over 2 km, becoming an easterly return flow in the upper level over the sea and making sea-breeze front with two kinds of sea-breeze circulations of a small one in the coast and a large one in the open sea. Convective boundary layer is developed with a thickness of about 1km over the ground in the upwind side of the mountain in the west and a thickness of thermal internal boundary layer from the coast along the eastern slope of the mountain is only confined to less than 200 m. On the other hand, after sunset, no prohibition of upslope wind generated during the day and downward wind combined with mountain wind from mountain towardplain and land-breeze from land toward under nocturnal radiative cooling of the ground surfaces should intensify westerly downslope wind, resulting in the formation of wind storm. As the wind storm moving down along the eastern slop causes the development of internal gravity waves with hydraulic jump motion in the coast, bounding up toward the upper level of the coastal sea, atmospheric circulation with both onshore and offshore winds like sea-breeze circulation forms in the coastal sea within 70 km until midnight and after that, westerly wind prevails in the coast and open seas.

Migration and distribution changes of the Sandfish, Arctoscopus japonicus in the East Sea (동해안 도루묵, Arctoscopus japonicus의 회유와 분포변동 특성)

  • Yang, Jae-Hyeong;Lee, Sung-Il;Park, Kie-Young;Yoon, Sang-Chul;Kim, Jong-Bin;Chun, Young-Yull;Kim, Sang-Woo;Lee, Jae-Bong
    • 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.

Influence of roadkill during breeding migration on the sex ratio of land crab (Sesarma haematoche)

  • Ryu, Mi;Kim, Jae Geun
    • Journal of Ecology and Environment
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    • v.44 no.4
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    • pp.207-211
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    • 2020
  • Adult land crabs generally live on land while their larvae live in the sea. In the case of Sesarma haematoche, female crabs migrate from land to sea to release the larvae at the high tide of syzygy night. Artificial structures along coastal areas are being obstacles for the migration of land crabs and causing synchronized roadkills on coastal roads during breeding migration. In this research, we compared the sex ratios of crab populations in coastal areas with coastal roads and uninhabited island areas with no road. The proportion of females in inland habitats with coastal roads was significantly smaller than island habitats. In particular, females are exposed to the risk of annually repeated roadkills, and the proportion of females decreases rapidly with their growth. If this tendency is general for land crab populations in the coastal areas with roads, significant road mortality of female land crabs during breeding migration can lead to severe population decline in coastal areas. Therefore, it is necessary to take an action to save land crabs crossing coastal roads.

Sea Environmental Design Criteria for Coastal and Offshore Structures

  • Liu, Defu
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1996.10a
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    • pp.19-22
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    • 1996
  • Extreme sea statistics and combinations of environmental events or response for structures are very important problem in performance evaluation and design of coastal and Offshore structures. A probabilistic method is developed that leads to the combination of Typhoon (Hurricane) or winter storm induces winds, waves, currents and surge for a generic site. The traditional recommendation for the fixed structures is a combination of the 100 years maximum wave height with the 100 years wind and current. (omitted)

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The right and duties of the coastal state over the continental shelf (연안국의 대륙붕에서의 권리와 의무)

  • Lim, Chae-Hyun;Lee, Yun-Cheol
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.137-139
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    • 2006
  • The Continental shelf is important part of the coastal states' jurisdiction at sea, because there are many natural resources in continental shelf. This paper examines the concept and legal status of the continental shelf, the limit of the continental shelf, and expecially the rights and duties of the coastal state relating to its continental shelf.

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Estimation of the Effective Region of Sea/Land Breeze in West Coast Using Numerical Modeling (수치모델링을 이용한 서해안 지역에서의 해륙풍 영향권 산정에 관한 연구)

  • Jeong, Ji-Won;Lee, Im-Hack;Lee, Hee-Kwan
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.2
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    • pp.259-270
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    • 2008
  • The regional air movement in a coastal area is generated by the different heat capacities of sea and land sides, which is called sea/land breeze. In the west coast area, the local air quality is significantly influenced by this sea/land breeze. In this study, the mathematical model is proposed to estimate the effective area of sea/land breeze. A commercial air model, that is suggested as an alternative air model by USEPA, is introduced to simulate the mechanism of sea/land breeze generation. From this study, it is confirmed that the numerical approach proposed in this study is reliable to predict the effective area of sea breeze in a coastal area. It implies that the current application of common air model needs to be carefully reviewed especially when dealing with a coastal air quality issue. It is also found that the sea breeze in Incheon area has the impact in the range of approximately 24 km in-land side, so-called penetration length.

A Study on the GIS for The Sea Environmental Management II (- Developing a Line Density Algorithm for The Quantification to the Sea Surface Temperature Distribution - ) (GIS을 활용한 해양환경관리에 관한 연구 II (해수면 수온분포의 정량화를 위한 선 밀도 알고리즘 개발))

  • Lee, Hyoung-Min;Park, Gi-Hark
    • Journal of environmental and Sanitary engineering
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    • v.21 no.4 s.62
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    • pp.61-76
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    • 2006
  • A Line Density algorithm was developed to quantify the sea surface temperature distribution using NOAA Sea Surface Temperature(SST) data and Geographic Information Systems(GIS), In addition, a GIS based automation model was designed to extract the Line Density Indices were determined by applying K-means Cluster. SST data in terms of March to May obtained on the coastal area of the Uljin from 2001 to 2004 in spring were used to make two data sets of average sea water temperature map in terms of year as well as month. From the result it was formed that water temperature gradient in April was the strongest among the other months, In particular very strog formation of oceanic front as well as temperature gradients were observed in front of the coastal area around Wonduk and Jukbyeon countries. Because those coastal area is a confront zone of two cold and a warm. It is expected that the development of a Line Density Algorithm would contribute to quantify of the SST for the research of Sea Surface Front(SSF) related to marine life management and the sea environmental conservation.

The Approach of Land Use Planning for Climate Change on Coastal Areas - Focus on the Case of US, Mediterranean Sea and Caribbean Sea Coastal Areas - (기후변화 적응을 위한 연안완충구역 정책 개선방안 - 미국 연안도시와 지중해, 카리브해 연안지역 사례를 중심으로 -)

  • Jiwoon Oh;Hansol Mun;Yeonju Kim;Jiwoo Han;Juchul Jung
    • Journal of Environmental Impact Assessment
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    • v.33 no.1
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    • pp.18-29
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    • 2024
  • The aggravation of coastal erosion due to climate change has recently emerged as a global issue, and the international community is aware of the risk and is applying national consultations and various policies. In the case of coastal countries located in the Mediterranean Sea and the Caribbean Sea, coastal buffer zones and coastal management plans are established at a national level, and the United States is establishing coastal area management plans at the city level. In Korea, coastal erosion management areas are designated and managed to prevent coastal erosion and coastal disasters, but the number of designated areas and policies for coastal land areas are lacking. Therefore, in this study, we study policy cases applied to coastal land to prevent and reduce coastal erosion and coastal disasters through policy status and overseas cases, and seek ways to improve coastal buffer zone policies. As a result of the study, implications were drawn that expansion of the coastal buffer zone for coastal land areas and standards for establishing buffer zones based on scientific analysis are necessary.

Heat Budget in Incheon Coastal Area in 1994 (1994년 인천 연안역의 열수지)

  • 최용규;윤홍주
    • Journal of Environmental Science International
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    • v.8 no.3
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    • pp.293-297
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    • 1999
  • Based on the monthly weather report of Korea Meteorological Administration (KMA) and daily sea surface temperature (SST) in Incheon harbor of National Fisheries Research and Development Institute, heat budget in Incheon coastal area was estimated. The temperature differences between the sea surface and near bottom were nearly within 1$^{\circ}C$. This indicate the mixing from the sea surface and the bottom. The net heat flux through the sea surface and the advection through the inner and outer bay was affected uniformly to the water body in Incheon coastal area. The net heat flux was about 110W/$m^2$ in maximum value on May, about -80W/$m^2$ in minimum on January. The net heat flux through the sea surface from the solar radiation was about 2.35$\times$${10}^5$W during the year. This heat flux flew out the bay through the advection by the same flux.

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