• 대한지리학회지
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• 제33권2호
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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.

• 한국환경과학회지
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• 제23권5호
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• pp.801-806
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• 2014

Long-term change in sea level along the eastern coast of Korea was illustrated using four tide-gauge station (Pohang, Mukho, Sokcho, Ulleung) data, water temperature and salinity. Seasonal variation in the sea level change was dominant. The sea level change by steric height derived from water temperature and salinity was relatively lower than that measured from the tide-gauge stations. Sea level rising rate per year by steric height increased with latitude. The effect of salinity(water temperature) on the sea level change is greater in winter(in summer).

• 대기
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• 제29권4호
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• pp.367-380
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• 2019

Global warming causes various problems such as the increase of the sea surface temperature, the change of coastlines, ocean acidification and sea level rise. Sea level rise is an especially critical threat to coastal regions where massive population and infrastructure reside. Sea level change is affected by thermal expansion and mass increase. This study projected future sea level changes in the 21st century using the HadGEM2-AO with RCP8.5 scenario. In particular, sea level change due to water mass input from ice-sheets and glaciers melting is studied. Sea level based on surface mass balance of Greenland ice-sheet and Antarctica ice-sheet rose 0.045 m and -0.053 m over the period 1986~2005 to 2081~2100. During the same period, sea level owing to dynamical change on Greenland ice-sheet and Antarctica ice-sheet rose 0.055 m and 0.03 m, respectively. Additionally, glaciers melting results in 0.145 m sea level rise. Although most of the projected sea level changes from HadGEM2-AO are slightly smaller than those from 21 ensemble data of CMIP5, both results are significantly consistent each other within 90% uncertainty range of CMIP5.

• 한국수산과학회지
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• 제32권6호
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• pp.803-808
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• 1999

Trend of sea level change has been analysed by using the tidal data gathered at the 12 tide stations along the coast of Korean peninsula. Analysis and prediction of the sea level change were performed by Principal Component Analysis (PCA). For the period of 20 years from 1976 to 1995, the trend generally shows a rising pattern such as 0.22 cm/yr, 0.29 cm/yr, and 0.59 cm/yr along the eastern, southern, and western coast of Korea, respectively. On the average the sea level around the Korean peninsula seems to be rising at a rate of 0.37 cm/yr. Adopting the average rate to the sea level prediction model proposed by EPA (Titus and Narrayanan, 1995), the sea level may be approximately 50$\~$60 cm higher than the present sea level by the end of the next century.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.222-222
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• 2015

Vietnam is one of the most vulnarable countries affected by climate change and sea level rise. One of the consequences of climate change and sea level rise is the increase of salinity intrusion into the rivers which is challenging to irrigation systems in coastal areas. This indicates the necessary to study the ability of taking water through sluice gates of irrigation systems in coastal zones, especially in the dry season with the effects of climate change and sea level rise in the future. In this paper, Nam Thai Binh irrigation system is selected as a case study. The irrigation system is one of 22 biggest irrigation systems of the Red River delta in Vietnam located in coastal region. The computed duration is selected in dry season to irrigate for Winter-Spring crops. The irrigation water for the study area is taken from different sluice gates along the Red River and the Tra Ly River. In this paper, MIKE-11 model was applied to assess the ability of taking water for irrigation of the study area in current situation and in the context of climate change and sea level rise senario in 2050 (under the medium emissions scenario (B2) published by the Ministry of Natural Resources and Environment of Vietnam published in 2012) with different condition of water availability. The operation of the gates depends on the water levels and sanility conditions. The sanility and water level at different water intake gates of Nam Thai Binh irrigation system were simulated with different senarios with and without climate change and sea level rise. The result shows that, under climate change and sea water level rise, some gates can take more water but some can not take water because of salinity excess and the total water taking from the different gates along the rivers decrease while the water demand is increase. The study indicates the necessary to study quantitatively some recommended solutions in the study area particularly and in coastal region generally in Vietnam to ensure water demand for irrigation and other purposes in the context of climate change and sea level rise in the future.

• Ocean Systems Engineering
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• 제7권4호
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• pp.319-328
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• 2017

Higher prediction efficacy is a very challenging task in any field of engineering. Due to global warming, there is a considerable increase in the global sea level. Through this work, an attempt has been made to find the sea level variability due to climate change impact at Haldia Port, India. Different statistical downscaling techniques are available and through this paper authors are intending to compare and illustrate the performances of three regression models. The models: Wavelet Neural Network (WNN), Minimax Probability Machine Regression (MPMR), Feed-Forward Neural Network (FFNN) are used for projecting the sea level variability due to climate change at Haldia Port, India. Model performance indices like PI, RMSE, NSE, MAPE, RSR etc were evaluated to get a clear picture on the model accuracy. All the indices are pointing towards the outperformance of WNN in projecting the sea level variability. The findings suggest a strong recommendation for ensembled models especially wavelet decomposed neural network to improve projecting efficiency in any time series modeling.

• 한국제4기학회지
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• 제18권2호통권23호
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• pp.75-86
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• 2004

The sea level curve and environmental change were reconstructed at Sejuk-ri during the early Neolitic Age, based on the sedimentary facies, the distribution of remains and carbon datings. Before 6,500 years BP, the sea-level experienced one oscillation. The Neolitic men utilized geomorphic environment which formed according to the sea-level change. They might be occupied in gathering, fishing and hunting including whales hunting. The Neolitic men made acom hollows in order to remove tannin. Besides, they remained shell mounds which were formed from 6,500 years BP to around 6,000 years BP. They left the living place about 6,000 years BP because of transgression.

• 한국해양학회지
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• 제29권3호
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• pp.228-238
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• 1994

제4기 동안에 일어난 해수면 변화는 지역적 그리고 나아가 전 지구 기후변화에 좋 은 지시자가 되고 있다. 세계 해수면은 제 4기 동안 매우 불규칙하게 변해왔는데 여기 에 대한 정밀한 수학적 접근은 어려운 실정이었다. 이 연구에서 처음으로 세계 해수면 변동자료에 확율 프랙탈을 적용하여 제4기 해수면 변동을 재구성 하였다. 미국 대서양 연안에 위치한 허드슨만과 델라웨어 해안의 홀로세 해수면 변화에 대한 프랙탈 차원을 상자 계산 방법으로 측정한 결과, 허드슨만 해수면 분노는 프랙탈 차원이 1,358이고 델라웨어 해수면 변화는 1,346이다. 프랙탈 내삽함수의 역산 방법 (IFIF)의 유효성이 허드슨만과 델라웨어 해수면의 내삽에 의해서 검증되었고, IFIF에 의해서 두지역에서 의 합리적인 해수면들이 복원되었다. 델라웨어 해수면 자료는 허드슨 해수면 자료보다 IFIF의 내삽에 대해 통계적 오차가 적게 나타나는데, 이는 델라웨어 해수면 자료가 허 드슨 자료보다 더 신빙성이 높다는 것을 의미한다. IFIF는 한국 해안의 해수면을 추정 하는 데도 이용되었는데, 한국 해안의 해수면 자료는 허드슨만이나 델라웨어 지역보다 자료가 충분치 못하다. 따라서 IFIF 의 적용 통계 오차가 적은 텔라웨어 해수면 자료 에서 구한 프랙탈 차원을 사용하여 한국 해안에 대한 IFIF의 수직 비율 인자를 계산하 였다.함수(FIF)를 한국 해안과 미국 대서양 연안의 고해수면의 재구성에 적용한 결과,한국의 고해수면은 미국의 고해수면과 다른 변화를 보였다.8000년 전부터 현재까지 두지역의 해수면은 비교해 보면 한국 해수면이 미국 해수면 보다 훨씬 높았다.

• 한국지형학회지
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• 제28권4호
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• pp.31-39
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• 2021

Gaemok, the place name of Uihang-ri, Sowon-myeon, Taean-gun, Chungnam, indicates a tombolo. This study estimated the Holocene sea level change and development process of the coastal landforms of the Gaemok and Hwanyeong Tombolos in the Uihang coast. The tombolos seemed to form at approximately 3.4 ka and the average sea level at that time was estimated to be higher than that of the present by ca. 1 m. The Gaemok area was a separated island from the Taean peninsula during the Holocene Climatic Optimum. At approximately 3.4 ka when the sea level rose again after the fall, the Gaemok area was tied to the land by formation of the Gaemok and Hwanyeong Tombolos. The falling or fluctuating sea levels after 3.4 ka have shaped the present coastal landforms.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.312-316
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• 2002

Satellite radar interferometry data shows a strong coherent signal on oyster sea farms where artificial structures installed on the bottom. We obtained 21 highly coherent interferograms from eleven JERS-1 SAR data sets despite of large orbital baseline (~2 km) or large temporal baseline (~l year). The phases observed in sea farms are probably induced by double bouncing on sea surface, and consequently reveal a tide height variation. To restore the absolute sea level changes we counted the number of wrapping by exploiting the intensity of backscattering. Backscattering intensity is closely correlated with the change in water surface height, while interferometry gives the detailed variation within the limit of 2$\pi$ (or 15.3 cm). Comparing the radar measurements with the tide gauge records yielded a correlation coefficient of 0.96 and an ms error of 6.0 cm. The results demostrate that radar interferometry is promising to measure sea level.