• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.3
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• pp.143-148
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• 2010

Changes in coastline length and land area as well as coastline attribute distribution in Anmyondo were quantified by comparing topographic map produced in 1910's with coastline survey database compiled in 2003. Numerous reclamation has simplified complicated coastline, which resulted in reducing coastline length by 58% but increasing land area by 36%. In 2003, gravel coastline was mostly dominated. Coastline of tidal barrier also reached up to 33% of overall coastline. Gravel coastline occurred dominantly at the eastern side of Anmyondo, whereas sand coastline at the western side. An application of coastline attribute to coastal erosion zone required accurate coastline data, but it was conceived that the topographic map produced in 1910's was not useful for this purpose.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.148-156
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• 2002

The coastline of Hampyung Bay, southwestern coast of Korea, was examined and measured in the field for the understanding of geomorphic changes and sea-cliff erosion processes. The Hampyung-Bay coastline is characterized by steep-face slope and soft soil and/or intensively weathered rock composition. Saw teeth-shaped coastline, and relict weathered basement-rock and "Island Stack" exposed on the beach surface are peculiar geomorphic features indicating active sea-cliff erosion. The coastline in the study area is continuously retreating with the following cyclic process: erosion of cliff base, gravitational landslide or mass wasting, formation of talus, and then erosion and removal of talus. In this study, sea-level rise during summer in the west coast of Korea is suggested as one of the key factors fur the removal of soil taluses and, thereby, accelerating sea-cliff erosion.f erosion.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.202-206
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• 2015

해안선은 길게 뻗어 있지만 직선적이지 않고 원호와 같은 곡선을 보인다. 그러나 대부분의 평형 해안선식은 직선적 해안이라고 가정하고 수립되어 그 효용성이 큼에도 불구하고 실 해안에 적용되는 경우 잘 재현하지 못하는 경우가 범용적으로 이용되는 데 큰 걸림돌이 되었다. 특히 해안선의 포괄 원호의 반경이 작을수록 문제가 크다는 점에 착안하여 해안선을 포괄하는 극좌표계에 포물선형 평형 해안선 식을 매핑하는 방법을 적용하였다. 그 결과 control point의 개연성을 극복하였고 대부분의 동해, 서해든 국내 해안에 적용한 결과 만족할 만한 결과를 제공하였다. Matlab GUI로 개발되어 실무자들이 항만이나 어항 등 연안해역 개발에 따른 침식 문제의 근본 해결 방안을 사전에 수립하는 데 큰 도움이 되리라 기대한다.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.423-430
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• 2013

An algorithm to allow shoreline movement during numerical experiment on sediment transport, deposition or resuspension for general coastal morphology is proposed here. The bed slope near shoreline, i.e. mean sea level, is influenced by bed material, tidal current, waves, and wave-induced current, but has been reported to remain within a stable range. Its annual variation is not large, either. The algorithm is adjusting the bathymetry, if the largest bed slope within shoreline band exceeds a given bed slope due to continuous erosion at zones below the shoreline. This algorithm automatically describes retreat of shoreline caused by erosion, when used within a numerical system. The algorithm was tested to a situation which includes a continuous dredging at a point, and showed satisfactory development of concentric circle contours. Next, the algorithm was tested to another situation which includes sinking of eroded part of bed plate, and produced satisfactory results, too. Finally, the algorithm was tested to a movable-bed laboratory experimental conditions. The shoreline movement behind detached breakwater was reasonably reproduced with this algorithm.

• Journal of the Korean Geographical Society
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• v.50 no.2
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• pp.147-164
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• 2015

This study analyzed characteristics and tendencies of seasonal change on shoreline and beach with 8 beaches at East Sea coast by topographical survey for 2 years from March 2012 to February 2013. The shorelines of East Sea coast appeared that amount of seasonal change was bigger than amount of annual change. The seasonal change tendencies between Gangwon-do and Gyeongsangbuk-do coast areas existed some regional differences. To synthesize seasonal changes on 8 beaches of East Sea coast, shoreline advance and beach deposit showed clearly in summer and shoreline retreat and beach erosion showed clearly in autumn. This result is different from tendencies of seasonal change in many mid-latitude coast areas of the world, but generally corresponds with reference studies in west coast and east coast. The major factor of beach erosion showing mostly in summer is storm wave caused by typhoon. The beach erosion by storm wave also occurred in late winter. And it assumes that the beach deposit showing mostly in autumn is result of equilibrium processes of coast area against strong erosion in summer.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.490-495
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• 2004

안목항의 방파제 확장 건설로 인하여 항남측에 심각한 침식현상이 광범위하게 발생하고 있는 데 이를 규명하기 위하여 현재 주변 해안선 변형 현상을 기초로 연안 표사 이동(littoral drift)도를 정성적으로 작성하였으며 수치 모형실험을 통하여 상세할 표사이동의 변화를 살펴보았다. 수치모형 실험은 파랑 변형 및 해빈류 예측 모형인 WADEM-P, DISEM-R로 수행되었다. 항 내 매몰 및 하천 폐색을 근본적으로 해결하면 해안선 침식문제를 완화 시 킬 수 있는 장치로서 모래운송장치(sand transfer)의 필요성이 언급되었으며 앞으로 연안 표사량이 많은 동해안에서의 항만 건설시 꼭 필요한 부대장치임을 강조한다. 또한 주기적인 연안관측 프로그램을 수립하여 연안 표사량 및 해안 침식율을 산정한 후 모래이송장치의 설치 여부 및 그 규모를 판단할 필요가 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.32-32
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• 2016

정부는 1999년 제정된 연안관리법에 따라 2000년부터 시행 중인 '연안정비계획' 등을 통하여 연안 침식 대응사업을 지원하고 있다. 그러나 연안의 개발은 지속적으로 일어나고 있으며 그 중 동해항 3단계 북방파제 축조공사가 내년 3월 중으로 착공할 것으로 예상된다. 동해항 3단계 개발사업은 동해항을 환동해권 물류 중심 거점 항만으로 육성하기 위해, 오는 2020년까지 대규모 항만개발과 방파제 등이 축조될 예정이다. 이에 따라 본 연구에서는 동해항 3단계 개발사업의 추진에 따른 인근해변의 해안침식 저감대책 방안으로 해안선 및 수심 변화를 예측하고자 한다. 동해항 인근의 추암 해수욕장부터 삼척 해수욕장까지 대상지역 N-line 모델 적용 및 Case분석을 실시한다. 해안선 변화는 Polar coordinate에서 개발된 One-line 모델에 회절 효과를 반영하고 해빈 경사와 쇄파고에 따라 횡단 방향으로 발생하는 표사로 인한 추가적인 해안선 변화 효과를 반영하여 입사파고 변동에 따른 단기적인 해안선 변화의 변동 폭을 제공한다. 연평균 입사 파고에 따라 형성되는 연안방향 표사로부터 해안선이 변동하며 이 해안선을 기준으로 연평균 파고에 따른 전진 폭과 최고 파고에 따른 침식 폭을 제시한다. 동해항 개발 전 변화 예측 모델링과 동해항 개발 후 변화 예측 모델링을 통해 개발에 따른 장래 해안선의 변화 예측 모델링 결과 분석 및 검토를 실시, 동해항 인근 지역에 적합한 해안선 유지관리 방법 결정 및 제안을 하는데 도움을 줄 것이라 기대된다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4D
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• pp.561-567
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• 2008

In this study, shoreline change was analyzed by RTK-GPS and advanced airborne LiDAR survey. For extraction of coastline, first of all, tide correction was conducted at all RTK-GPS points through the comparing with the corresponding tidal height, and cross section providing coastline was produced using Autocad Civil3D program. Comparing with two results of RTK-GPS (first, 29 Aug 2007; second, 6 Oct 2007) surveys, coastline of the first result had been decreased about 21m compare with that of the second. And it was also demonstrated that the length of coastline by the first RTK-GPS was 15m shorter than that by the airborne LiDAR survey (Dec. 2006). In addition, we recoquized that the erosion appeared in the top right-hand (dock area); the sediment in the bottom left-hand (Chosun beach area) of the Haeundae beach. As a result, therefore, it was learned that artificial sand filling for beach open and natural effects such as a typhoon, current drift, wind direction gave cause for area changes and coastline.

• Journal of the Korean earth science society
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• v.22 no.4
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• pp.317-326
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• 2001

The coastline of semi-enclosed Hampyung Bay, southwestern coast of Korea, consists largely of erosional sea-cliffs characterized by steep face slope, low in height (less than 3m), and composition of soft reddish soil. Recession rates of the sea-cliffs in the Haeuri coast of Hampyung Bay, which were Quantified by photogrammetry using single aerial photographs taken 1976 and 1990, respectively, were approximately 1${\sim}2m/yr. This value is in good agreement with the field measurement conducted by Chang et al. (1999). Subsequently, the photogrammetry seems to be a very useful method to measure easily long-term coastline change. This severe erosion of sea-cliff in the semi-enclosed bay environment, furthemore, is probably due to combined effects of typhoon or/and storm surges and weak resistance of soil cliff itself.

• Korean Journal of Remote Sensing
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• v.29 no.5
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• pp.477-486
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• 2013

To analyze tendency of temporal and spatial change of shorelines and to estimate rate of shoreline changes using long-term shoreline change data is very important for the coastal environmental management. In this study, investigation was conducted to estimate the rate of shoreline changes using long-term shoreline change data from the year 1985 to 2009 aerial photographs. In this process aerial triangulation, GPS surveying and digital mapping was done for the estimation of changes. As the results, shorelines of Bangpo and Kkotji Beach retreated at a maximum rate of 0.2 m/yr and 0.8 m/yr, respectively. The shoreline could be changed by various factors. However, it was presumed that coastal erosion has been mainly affected by retaining wall constructed in the late 1990s.