• Journal of the Korean Geographical Society
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• v.33 no.2
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• pp.143-163
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• 1998

In order to clarify the depositional environment and sea-level change at Ilsan area including Gawaji and Saemal valley plains, which is located at the right side in downstream of the Han River, boring data, radiocabon dating and diatom analysis were comprehensively investigated. As a result, the palaeogeographies fo this area altered by the transgressions and regressions after 7,000 y. BP could be restored. The high tide sea-level(mean high water level of spring tide) was arrived ca. 7,000y. BP at the valley plain and risen to ca. 5.5m at ca. 5000y. BP. Since then, the sea-level was kept up the same level to ca. 3,200 BP. The descended sea-level to ca. 2,300 BP was risen up to ca. 5.8m in ca. 1,800 y. BP. It is presumed that such a sea-level change as well as the different sediments in quantity supplied from the river basin of the valley plain could be effected to change diversely the depositional environment of the study area and eventually to the prehistoric human life.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.1
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• pp.15-24
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• 2012

This study aims to investigate characteristics of water quality factors by using survey results of national marine environmental monitoring system from 2004 to 2010 at coastal area of the East Sea of Korea. In this study, we chose statistical methods to analyze the correlation among water quality parameters and principal component analysis for characteristics of each water environment. In addition to this, we evaluated each water's pollution level based on eutrophication standard of OECD, Eutrophication Index(EI), and Organic Pollution Index(OPI). Major factors were chlorophyll a and salt according to the analysis at coastal area of the East Sea. The sea was divided into the south and the central part by Jukbyeon. Also, Jukbyeon in the central part of the East Sea and Gampo in the southern sea coastal waters have been classified separately. The nutritional status of coastal area of East Sea presented Mesotrophic to Oligotrophic level and EI showed less than 1. OPI in all of the coastal area at the East Sea represented that the water quality condition was favorable.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.506-515
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• 2011

To elucidate demersal organism community structure, abundance, and biomass by period and region in the Uljin marine ranching area, otter trawl surveys were conducted at six stations from February 2008 to December 2009. During the survey period, a total of 118 species was collected in the Uljin marine ranching area, including 76 pisces, 27 mollusca and 15 crustaceans. The average abundance of individuals was 806 ind./$m^2$ and average biomass was 31,853 g/m2. The numbers of species, species richness, individuals per area and biomass per area were higher in 2009 than in 2008. Cluster and MDS analysis, based on a Bray-Curtis similarity matrix of fourth root transformed data of number of species and individuals per area, showed division into two different groups of demersal organisms in 2008 (Group 1) and one demersal organism community in 2009 (Group 2). From cluster and MDS analysis using the similarity of the demersal community among six stations, the Uljin marine ranching area was divided into Group A (St. 2, St. 4, St. 5 and St. 6) and Group B (St. 1 and St. 3).

• 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.

• 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.

• Journal of the Korean Society of Marine Environment & Safety
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• v.5 no.2
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• pp.125-139
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• 1999

Thanks to the fact that the 1953 Korea Armistice Agreement does not have any clear provisions on the sea demarcation line, the North Korea insists that the sea demarcation line in the Yellow Sea Area should not be the NLL designated by the Commander in Chief. UN Command, unilaterally, but the hypothetical extention of the Latitude Parallel from the end of the provincial boundary line between Whanghae-do and Kyongki-do In those unique situations at the end of the Korean War, the cease-fire line on the part of the western sea area, a logically indispensable element of the contents of an armistice agreement, however has formed and crystallized by the act of the UN Command designating the NLL. In implementing the South-North Korean Basic Relations Agreement, a fair and clear common consent on the sea demarcation line in the western sea area should be deliberated.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.726-734
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• 2018

The total number of Sea Area Utilization Consultation in the environment management sea areas reviewed from 2015 to 2017 were 60. The number of development projects in the environment conservation sea areas decreased steadily, but special management sea areas increased. Development types in environment management sea areas showed that artificial structure installation was the highest ratio, followed by fishery port development and construction of habor and coastal maintenance and sea water intake and draining. By comparing the trend of water quality changes using marine environment information system (MEIS) data in the environment management areas from 2006 to 2017, COD showed no significant changes but the environment conservation sea areas increased slightly, and the concentration of TN and TP decreased. Gwangyang and Masan bays in the special management sea areas and Gamak bay in the environment conservation sea areas displayed oxygen deficient mass in the summer. As the use of development projects of the environment management sea areas are performed continuously, an analysis of the status of sufficient water quality changes is necessary for environmental impact assessment (Sea Area Utilization Consultation) in the marine environment and should be evaluated mainly for management of contamination by diagnosing thoroughly water quality effects and the pollution of sediment. Especially, the water quality goal for the purpose of designation in each of the environment management sea areas is set clearly, connection with pollution source control and the total pollution load management system (TPLMS) should be proposed and measured to reduce the amount of contaminated water.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.3
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• pp.345-360
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• 2004

The late sea-breeze and its impacts on ozone distributions were investigated during April to September from 1998 to 2002, in the Busan metropolitan area (including surrounding areas) using the surface ozone concentrations (obtained at 9 monitoring sites), local meteorological variables (obtained near the shore), together with synoptic data. The urban scale ozone concentration was also simulated using the MM5/UAM-V to better understand the role of late sea-breeze in Busan. The results from observation study showed that most of the late sea-breeze occurred when weak offshore synoptic flow (northwesterly) suppressed development of sea - breeze, and the ozone concentration level and frequencies exceeding ozone standard increased with the onset time of sea breeze. We also found that the late sea-breeze clearly induces relatively weak wind speed and high temperature during the daytime As a result it enhances the photochemical ozone accumulation and delays the occurrence time of the averaged maximum ozone concentrations. The results of simulation for high ozone episode (24 August, 2001) by MM5/UAM -V revealed that the late sea-breeze interacted with weak offshore synoptic wind can contribute significantly to high ozone concentration in the coastal urban area. The simulated horizontal and vertical distribution of ozone concentration indicated that ozone can be accumulated over the sea under stagnant condition and return to the land in the late afternoon with the sea breeze, suggesting both the relationship between late sea-breeze and recirculation and the importance of late sea -breeze effects influencing severe ozone pollution in Busan.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.1
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• pp.1-15
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• 2004

Sea/land circulation system is a representative mesoscale local circulation system in coastal area. In this study, wind fields around coastal area. Pohang, which is affected by this system was investigated and its detailed characteristic analysis was carried out. The following can be found out from the numerical simulation. Generally, at nighttime mountain winds prevail and land breeze toward the coastal area was well simulated During daytime, valley wind and sea breeze was simulated in detail. Especially, as a result of analyzing the land breeze path, it could be found along the coastline as it flows out through low land coastal area. In order to investigate the accuracy of model results. wind speed, temperature and wind direction of continuous typical sea/land breeze occurrence day was compared with observation data. Analyzing the characteristics of local circulation system was very hard because of horizontally sparse observation data but from the above result, a numerical simulation using RAMS, which satisfies the spatial high resolution, will provide more accurate results.

• Journal of Environmental Science International
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• v.22 no.10
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• pp.1363-1371
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• 2013

In this study, we estimate the interannual spatial and temporal distributions of fishing grounds at night in the East Sea based on satellite and in-situ data. We observe that the $15^{\circ}C$ thermal front moves in the north-south direction according to the movement of the warm water (above $18^{\circ}C$) in the Tsushima Warm Current (TWC) area, forcing the cold water area (below $10^{\circ}C$) to either expand or shrink. The interannual variations of sea surface temperature (SST) in winter represented by the indicator SST of $6^{\circ}C$ are consistent with the east-west zonal areas in the central East Sea which represented over $1^{\circ}C$ standard deviation of SST in February during 1990-2000. Annual SST in the fishing grounds of common squid fishing vessels, observed both by fishing vessels and satellites range from 9-$22^{\circ}C$, with the satellite-observed data having a larger range than the fishing vessel-based ones. The interannual distributions of the common squid fishing grounds in the East Sea are mostly concentrated in the TWC area in the southwestern part of the East Sea and in the coast of southern Honshu and Hokkaido in Japan. The interannual distributions of the nighttime fishing vessels are consistent with the catches investigated from the fishing vessel.