• Journal of Korean Society of Coastal and Ocean Engineers
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• v.2 no.1
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• pp.34-42
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• 1990

The tides in the Saemanguem Area, the western coast of Korea have been examined based on simulations with barotropic depth-integrated model. As a first step tidal computations were performed with open-boundary sea level forcing from four major constitutents ($M_2$, $S_2$, $K_1$, and $O_1$). Subsequently the established model was utilized to investigate the effect of construction of tidal barriers for Saemanguem development plan on the existing tidal regime. It has been shown that tide of semi-diurnal constituents may be reduced to 2-7 cm in amplitude along the frontal area of proposed barrier. In connection with above changes the tidal current regime may be subjected to significant reduction in intensity. thus suggesting the high possibility of sedimentation along the frontal region of tidal barrier.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.5
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• pp.228-238
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• 2017

In coastal region, tidal harmonic constants of semi-diurnal tides and nonlinear tides were collected. The observed tide data of KHOA were analyzed by a tide harmonic analysis method. In the southwestern coasts and Han river estuary, nonlinear tides are clearly generated. The generation of tide non-linearity and tide asymmetry is closely related with tide form factor in Korean coastal zone. Tide non-linearity and asymmetry in Mokpo harbour have increased by a series of coastal development projects. The increase has caused rise of high water level and drop of low water level, and increase of tidal range. In Kunsan Outport, tidal range has been declined due to inter-annual change of nonlinear tides after completion of Samangeum sea-dyke.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.4
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• pp.255-265
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• 2013

In the coastal region of Korea, historical tide harmonic constants were collected. Long-term tides and short-term tides observed by the KHOA were analyzed by a tide harmonic analysis method. Based on the harmonic constants, tidal characteristics such as tide asymmetry in Korean coastal waters were investigated. The harmonic constants obtained from the long-term tide data in the western coast have been used to show the relation between tide variation and reclamation project. $M_2$ amplitudes in the western coast have been decreased and $M_2$ phases were faster. $M_4$ amplitudes also were reduced and $M_4$ phases were faster in overall. In Mokpo and Kunsan tidal nonlinearity is relatively conspicuous. Overall, non-linearity of tidal currents is higher in the tidal channels flowing fast. The tidal non-linearity has increased by the development projects including large reclamation. The flood dominant characteristic in the northern and central part of Korean western coastal waters and the ebb dominant characteristic in the southern part have been intensified. The construction of Saemangeum sea dike has significantly changed the tidal characteristic in Korean western coastal waters.

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.2
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• pp.73-84
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• 1992

The TIDE, finite element model for the simulation of tidal flow in shallow sea was tested for its applicability at the Saemangeum area. Several pre and post processors were developed to facilitate handling of the complicated and large amount of input and output data for the model developed. Also an operation scheme to run the model and the processors were established. As a result of calibration test using the observed data collected at 9 points within the region, linearlized friction coefficients were adjusted to be ranged 0.0027~0.0072, and water depths below the mean sea level at every nodes were changed to be increased generally by 1 meter. Comparisons of tidal velocities between the observed and the simulated for the 5 stations were made and obtained the result that the average relative error between simulated and observed tidal velocities was 11% for the maximum velocities and 22% for the minimum, and the absolute errors were less than 0.2m/sec. Also it was found that the average R.M.S. error between the velocities of observed and simulated was 0.119 m/sec and the average correlation coefficient was 0.70 showing close agreement. Another comparison test was done to show the result that R.M.S. error between the simulated and the observed tidal elevations at the 4 stations was 0.476m in average and the correlation coefficients were ranged 0.96~0.99. Though the simulated tidal circulation pattern in the region was well agreed with the observed, the simulated tidal velocities and elevations for specific points showed some errors with the observed. It was thought that the errors mainly due to the characteristics of TIDE Model which was developed to solve only with the linearized scheme. Finally it was concluded that, to improve the simulation results by the model, a new attempt to develop a fully nonlinear model as well as further calibration and the more reasonable generation of finite element grid would be needed.

• Korean Journal of Remote Sensing
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• v.25 no.4
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• pp.339-357
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• 2009

The Saemangeum Reclamation Project was launched as a national project in 1991 to reclaim a large coastal area of 401 km$^2$ by constructing a 33-km long dyke. The final dyke enclosure in April 2006 has transformed the tidal flat into lake and land. The dyke construction has abruptly changed not only the estuarine tidal system inside the dyke, but also the coastal marine environment outside the dyke. In this study, we investigated the spatial change of SST distribution using the Landsat-5/7 and NOAA data before and after the dyke completion in the Saemangeum area. Satellite-induced SST was verified by compared with the various in situ measurements such as tower, buoy, and water sample. The correlation coefficient resulted in above 0.96 and RMSE was about 1$^{\circ}C$ in all data. 38 Landsat satellite images from 1985 to 2007 were analyzed to estimate the temporal and spatial change of SST distribution from the beginning to the completion of the Samangeum dyke's construction. The seasonal change in detailed spatial distribution of SST was measured, however, the estimation of change during the Saemangeum dyke's construction was hard to figure out owing to the various environmental conditions. Monthly averaged SST induced from NOAA data from 1998 to 2007 has been analyzed for a complement of Landsat's temporal resolution. At the inside of the dyke, the change of SST from summer to winter was large due to the relatively high temperature in summer. In this study, multi-sensor thermal remote sensing is an efficient tool for monitoring the temporal and spatial distribution of SST in coastal area.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2007.05a
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• pp.308-311
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• 2007

황해의 25개 조사정점의 표층수에 대한 해양환경요인 및 식물플랑크톤 현존량의 월별 조사결과를 종합하여 주성분분석(PCA)을 실시한 결과 주성분 I에서는 변화를 26.6% 설명할 수 있으며, 이중 질산질소가 가장 많이 기여하였고, 이어서 용존무기질소, 규산규소, 수온, 용존산소, 암모니아질소 순으로 기여 하고 있었다. 주성분 II에서는 20.3%를 설명 할 수 있으며, 이중 용존산소가 가장 많이 기여하였고 그 외 엽록소 a, 수온, 염분, 규산규소, 식물플랑크톤 현존량 순으로 기여 하였다. 주성분 III에서는 15.1%를 설명 할 수 있으며, 이중 인산인이 가장 많이 기여하였고 그 외 염분, 아질산질소, 수온, 용존산소, 질산질소, 용존무기질소 순으로 기여하였다. PCA에 이용된 항목 중 부유물질은 제외한 모든 항목은 주성분 I, II, III에 5%이하 유의수준에서 의미 있는 상관성이 있었다. 주성분 I은 질산성질소, 용존무기질소, 규산규소, 인산인과는 긍정적인 상관성(p<0.0001)을 갖고, 수온, 암모니아질소와는 부정적인 상관성을 보였다(p<0.001). 주성분 II에서는 용존산소, 엽록소 a, 식물플랑크톤 현존량은 긍정적 상관성을 나타내었고, 수온, 염분, 규산규소와는 부정적인 상관성을 보였으며(p<0.0001), 주성분 III에서는 염분, 수온, 질산질소, 용존무기질소, 식물플랑크톤 현존량과는 긍정적인 상관성(P<0.0001)을 나타내었고 인산인, 아질산질소, 용존산소는 부정적인 상관성을 나타내었다 (p<0.01). 공간적인 분포특성은 조사정점에 따라 항목별 결과에 대한 분산이 커서 일정한 특성을 도출하기가 어려운 상태이나 대체로 PCA II축을 기준으로 상부인 $1/4{\sim}2/4$분면에 북부와 중부의 조사정점이 위치하고 음의 방향인 $3/4{\sim}4/4$분면에 중부와 남부의 조사정점이 위치하고 있어 북측의 307선과 308선 및 중부의 309선과 310선 그리고 남측의 311선과 312선으로 구분되어지는데 그 중에서 태안반도의 연안역인 307선의 03점은 계절에 변화가 가장 커서 분산의 폭이 심한 상태로서 다른 조사정점들과 구분되어진다. 전반적으로 북측해역에서는 용존산소, 엽록소 a, 식물플랑크톤 현존량이 남측해역에 비해 상대적으로 많은 반면, 남측해역은 수온과 염분 및 규산규소가 높은 상태이었다. 북쪽인 307선과 308선은 연안역과 외해에서 상대적으로 영양염류가 높았으며, 중부인 309선과 310선은 연안역과 준 외해역인 07점과 09점에서 영양염류가 높았었고, 남부 해역인 311선과 312선에서는 연안역에서 영양염류가 상대적으로 높은 경향을 나타내었다. 즉 황해 동부는 연안역에서는 조석간만의 차가 심하고, 새만금 및 시호호등과 같은 대규모의 간척 매립으로 육상의 오염원이 자정작용을 거치지 못하고 직접 연안으로 유입되고 있는 실정이다. 또한 10여 년 전부터 육지의 모래부족으로 다량의 바다 모래가 채취되어 왔고 그 량이 점차 증가추세이며, 중부외해역에서는 각종 폐기물 투기로 점차 영양염류의 부하량이 증가되고 있어 특히 질소계와 인의 영양염류 농도가 높아지고 있는 추세이다. 시간적 변동특성은 전반적으로 순환하는 형태를 유지하고 있다. 2005년 2월에는 질산질소, 용존무기질소, 규산규소, 인산인, 용존산소가 높았었으며 4월로 접어들면서 항목 간에 분산되는 경향을 보이면서 수온, 엽록소 a 및 식물플랑크톤이 증가 하면서 해역에 따라 좌우로 분산되는 경향을 나타내었고 6월에는 아질산질소를 제외한 영양염류가 감소하는 경향을 보였다. 8월에는 6월에 비해 수온이 높아지고 규산규소, 질산질소, 용존무기질소 등이 약간 증가추세이었으며 10월로 접어들면서 증가추세가 더 높아졌었고 12월에는 질산질소, 용존무기질소, 규산규소, 인산인, 용존산소가 높아졌었다. 2006년 4월에는 2005년 4월에 비해 수온, 엽록소 a, 식물플랑크톤의 현존량이 높아져서 전년 동시기와 약간 다른 양상을 보이고 있었다. 즉 동계인 2월을 시작으로 반 시계 또는 시계 방향으로 순환하는 형태를 유지하고 있으며, 4월은 2개년 비교해 보았을 때 해마다 해양환경에 따라 그 순환 정도 및 형태가 다를 것으로 추정된다.