• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1995.10a
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• pp.104-107
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• 1995

지구온난화에 따른 해면상승이 일어난다면 한국 서해안과 같은 완경사의 간사지의 범람은 크게 일어날 것이다. 향후 2010년 까지의 해면상승에 대한 정량적인 예측에는 불확실성이 있으나 적어도 과거 1세기의 해면상승률 보다는 최소 2배이상일 것으로 추정되고 있다. 또한 IPCC(Inter-governmental Panel on Climate Change)는 각국이 100cm의 go면상승에 대한 영향평가를 수행할 것을 권장하였는데 미국 EPA는 이 보다도 더 비관적인 상승을 추정하고 있다. (중략)

• Journal of The Geomorphological Association of Korea
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• v.26 no.1
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• pp.59-78
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• 2019

The physical and chemical characteristics of more than 5 m sandy deposits behind the beach in Sinji-do Island are investigated and its burial ages are estimated using Optically Stimulated Luminescence. By the estimated burial ages of the sandy deposits, this section is divided into four sub-units: Unit I (6.2 ka), Unit II (23.2 ka), Unit III (115.9 ka), and Unit IV (115.9 to 127.5 ka). It can be proposed that the Unit I of a coarse sand deposited during the Holocene Climatic Optimum. Unit II, supposed to be the aeolian sediments, formed during the Last Glacial Maximum (LGM). It can be supposed that the study area was not affected by the marine processes during the LGM, directly. Unit III is more consolidated deposits of coarse silt to fine sand and deposited during the Last Interglacial Period. Unit IV mainly consist of beach gravels with sandy matrix deposited during the Marine Isotope Stage 5e (MIS 5e), and thus indicates that the sea level of the southwest sea had risen 3 to 5 m above present sea level during the MIS 5e.

• Journal of the Korean earth science society
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• v.35 no.2
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• pp.131-146
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• 2014

Multi-beam echosounder data and grain size analysis data of surface sediment were acquired and analyzed in order to investigate the shelf-to-slope morphology, geological character, and their geological controlling factors in the southwestern margin of the Ulleung Basin. According to the morphological character, the continental shelf can be divided into two parts: (1) shallow (~100 m) and steep ($0.5^{\circ}$) inner shelf, (2) deep (100-300 m) and gentle ($0.2^{\circ}$) outer shelf. The continental slope is featured with eight distinct topographic depressions of various spatial dimension (~121 $km^2$ in area) and head wall gradient (${\sim}24.3^{\circ}$). They are developed adjacent to each other and presumably formed by submarine landslides which have recurred under the strong influences of earthquakes and eustatic sea-level change. The inner continental shelf and the continental slope are dominated by fine-grained sediment, whereas the outer continental shelf is dominated by coarse-grained sediment. The surface sediment distribution seems dominantly influenced by eustatic sea-level change. The outer continental shelf is mostly covered by coarse relict sediment deposited during lowstand sea-level, while the inner shelf is covered with recent sediment during highstand sea-level. The surface of the continental slope is covered with fine-grained sediments which were supplied by hemipelagic advection process.

• Journal of Environmental Impact Assessment
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• v.6 no.1
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• pp.5-31
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• 1997

Strategic Environmental Assessment (SEA) is an assessment process integrated with policy and planning processes considering environmental impacts, not at the level of individual project, but at higher level of policy and plan. Presently, two systems for the SEA are being implemented in Korea. One is "the consultation of environmental investigation into a change in national land utilization", which is to be pre-discussed with the head of the related central administrative organizations, based on the respective individual code. The other is "the consultation of environmental investigation into an administrative plan and project", which is to be pre-discussed with the minister of the environments for the administrative plan. However, these two systems are not integrated procedures with the planning process. In other words, there is a separate post-environmental assessment after planning. Also concrete proposal is not yet prepared for the method and procedure of environmental investigation about details of the planning. Therefore, they do not playa role in taking precautions for environmentally sustainable development. In this study, for the effective environmental investigation at the level of planning, environmental assessment model to be integrated with urban comprehensive plans was developed. The results of this study can be summarized as follows: First, based on the analysis of systematic problems in environmental investigation of this country, the study compared and analysed the SEA method of foreign countries. derived the potential limitations in its applications to this country. Also, the new method in this study, is integrated into planning process by improving the limitations. Thus, we developed the SEA model for this country, which consists of seven steps ; Phase 1; establishing a work program, Phase 2; defining the scop. of the SEA, Phase 3; analyzing an existing environmental situation, Phase 4; examining the consistency with environmental policy, Phase 5; appraising and synthesizing the plan content, Phase 6; proposing recommendations, Phase 7; monitoring and feedback. Second, the two types of application program of the developed assessment model were proposed. One is to integrate this model into planning process, and the other is for the institute and ministry of environments to implement SEA after planning. An aim of this study was developing an environmental assessment model at the planning level which was not yet established in this country and was to apply the model to urban comprehensive plan for inspection. This research will make the effective operation of environmental investigation system possible at the planning level in this country and contribute to the environmental protection at the global level.

• Journal of Korean Society of Disaster and Security
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• v.13 no.2
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• pp.53-63
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• 2020

In this study, the two-dimensional flow analysis model Hydro_AS-2D model was used to simulate the situation of flooding in Seongsangu and Uichang-gu in Changwon in the event of rising sea levels and extreme flooding, and the results were expressed on three-dimensional topography and the optimal evacuation path was derived using BIM technology. Climate change significantly affects two factors in terms of flood damage: rising sea levels and increasing extreme rainfall ideas. The rise in sea level itself can not only have the effect of flooding coastal areas and causing flooding, but it also raises the base flood level of the stream, causing the rise of the flood level throughout the stream. In this study, the rise of sea level by climate change, the rise of sea level by storm tidal wave by typhoon, and the extreme rainfall by typhoon were set as simulated conditions. The three-dimensional spatial information of the entire basin was constructed using the information of topographical space in Changwon and the information of the river crossing in the basic plan for river refurbishment. Using BIM technology, the target area was constructed as a three-dimensional urban information model that had information such as the building's height and location of the shelter on top of the three-dimensional topographical information, and the results of the numerical model were expressed on this model and used for analysis for evacuation planning. In the event of flooding, the escape route is determined by an algorithm that sets the path to the shelter according to changes in the inundation range over time, and the set path is expressed on intuitive three-dimensional spatial information and provided to the user.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.371-378
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• 2021

In this study, in order to analyze the spatial distribution of cold water occurred in the Southeast Sea of Korea, the K-means clustering method was used to analyze the ocean observatory buoy of Gori and Yangpo and GHTSST Level 4 from 2016 to 2018. The buoy data was used to identify the change in sea water temperature and the cold water occurrence at Gori and Yangpo in the Southeast Sea. As a result, the sea water temperature of Gori and Yangpo decreased equally at the cold water occurrence. Therefore, the reciprocal of the sea water temperature and the variance of SST were compared to see the changes of SST when the cold water occurs. When the reciprocal of the sea water temperature increases, the dispersion of SST also increases. Through this, it can be seen that there is a change in the water temperature distribution of SST in the sea when the cold water occurs. After that, K-means clustering was used to classify the cold water. After analyzing the optimal K value for clustering by using the Elbow method, it was possible to classify a region with cold water. Through this, it is estimated that the spatial distribution and diffusion range of the cold water, and it can be estimated and used in future studies to identify damage caused by the cold water and predict spatial spread.

• 한국지형공간정보학회:학술대회논문집
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• 2004.10a
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• pp.167-173
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• 2004

The erosion(or sediment) reaches very serious level due to the aftermath by the imprudent reclamation on the coast. Continuous studies for long on coastline erosion may be warranted and possible countermeasures proposed because the change of the coastline has been progressed slowly for a long period of time in a wide area. Many experts anticipate that the global sea level's average increase by 19-35 cm due to global warming may certainly have an effect on the coastal erosion throughout the world. Thus, a more rigorous study on the causes of changing coastlines is particularly proposed to find ways to counteract any possible threats against coastal environments. In this study, Ortho aerial photo and hydrographic survey datum were utilized to quantitatively analyze coastal erosion and sediment patterns. This paper also seeks to prove that a parcel under the sea occurred due to relatively significant changes to the coastline. We created Ortho aerial photo using aerial photos taken each decade ('81, '93, '00), overlaid them onto a cadastral registration map, and calculated each amount of erosion and sediment while accounting for the tide level and without considering it. As the result of this study, we could propose that the methods of Ortho aerial photo and the marine observation datum were the effective ways of change detection in erosion, sediment, and artificial reclamation of the coastline for a long time.

• 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.

• The Korean Journal of Quaternary Research
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• v.24 no.1
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• pp.35-45
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• 2010

The aims of this study are to clarify the geomorphological development of a alluvial plain and discuss the vegetation environments and agriculture activities in the Wangpo-River alluvial plain at Neungsan-ri, Buyeo by analyzing geomorphological classification, sedimentary facies and age datings. The alluvial plain at Wangpo-River was formed by the influences of Geum-River with the sea-level rising during the Holocene. The basin of Wangpo-River consists of natural levees, back marsh-type alluvial plains, valley plains and hills. The natural levees by Geum-River largely distributes at the area where Wangpo-River flows to Geum-River and the alluvial plains at the middle and lower reach are the back marsh areas of Geum-River. Moreover, the area along Wangpo-River show higher contents of coarse materials and thinner peat sediments than the back marsh. The lower sandy deposits in the alluvium of Wangpo-River was formed with the influences of human in the Bronze Age during the sea level falling and the peaty deposits was formed due to the water level rising of Wangpo-River during the sea level rising in the early Iron Age.

• Journal of the Korean earth science society
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• v.30 no.4
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• pp.409-426
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• 2009

In the four sedimentary cores from Yeoja Bay, the analyses of grain size, benthic foraminiferal species compositions, assemblages and statistics were carried out to investigate the effects of late Holocene sea-level change on benthic foraminifera. The core sediments were mainly composed of fine-grained silt and clay. The benthic foraminifera were classified into 27 species of 16 genera, 30 species of 21 genera, 50 species of 29 genera and 52 species of 29 genera in Core YC-1 to 4, respectively. In the result of cluster analysis, it seemed that Group 1 (Core YC-1 and 2) of representative A. beccarii assemblages was deposited in upper bay environment and Group 2 (Core YC-3 and 4) of representative E. clavatum-A. beccarii assemblages was deposited in inner bay environment affected by offshore water. In the result of species composition analysis, the production frequency of A. beccarii was gradually decreased from low layer to upper layer, whereas production frequency of E. clavatum and P.F./T.F. was gradually increased to upward. These change patterns appeared in benthic and planktonic foraminifera seemed to reflect the late Holocene sea-level rise in Yeoja Bay.