• Journal of The Geomorphological Association of Korea
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• v.26 no.4
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• pp.97-106
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• 2019

This study aims to investigate geomorphological and geological landscapes in the Taeanhaean National Park to ensure they are well-preserved. This study discovered 390 geomorphological and geological landform resources distributed in the coastal zone of Taeanhaean National Park. Representative geomorphological and geological landforms include : sea cliffs, sea caves, wave-cut platforms, sea-stacks, pebble beaches, sand beaches, tidal flats, coastal dunes, coastal dune wetlands and folds (or micro folds) landforms. Deposition landforms are developed more and erosion and weathering landforms are less on the land zone than island zone. These landform resources vary from district to district and can be developed for geo-tourism resources. Combined efforts from the Taeanhaean National Park authorities and residents are essential to manage ecological programs using geomorphological and geological resources.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.5
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• pp.366-371
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• 2012

High swell has been known for the one of the main causes of beach erosion in the east coast of Korea. In this study, coastal topography changes due to high swells are simulated to find its effect on the backshore by using movable bed experiments and numerical experiments. Sea bottom topographical changes due to various incident waves were investigated using CSHORE model in the numerical experiments. Furthermore, the mechanism and the phenomena of beach erosion due to waves and high swells on the foreshore and backshore were analyzed and compared with movable bed hydraulic experiments.

• Proceedings of the KSRS Conference
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• v.1
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• pp.455-458
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• 2006

Stretching on the coastline of 70 km, the Tam Giang - Cau Hai Lagoon plays a very important role for the coastal ecology and socio-economic development of Hue region where was Vietnam's Ancient Kingdom Capital and recognized as a World's Cultural Heritage. Recently, coastal hazard in the lagoon have occurred seriously such as inlet movement and fill up, coastal erosion, flood and inundation, etc. These hazards have impacted on lagoon environment, resources, ecosystems, socio-economic and sustainable development of this coastal area. This paper present a case study using remote sensing data in combination with ground survey for monitoring the coastal hazards in Tam Giang - Cau Hai lagoon in recent decades. Analysis results find that during its natural evolution, the lagoon has been being in three situations of only one, two and three inlets. When inlets opened or displaced, coastal erosion have occurred seriously toward new balance condition. Flood and inundation occurs every rainy season in lowland plain around lagoon. The historical flood happened in early of November 1999 with six days long, created very terrible damages for Thua Thien Hue province. Remote sensing data with capability of regular update, large area coverage is effective provide real-time and continuous information for coastal hazards monitoring.

• 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 the Korean Society for Marine Environment & Energy
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• v.19 no.4
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• pp.266-273
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• 2016

Two-dimensional hydraulic experiments were performed to assess the impact of artificial seaweed on wave energy attenuation, and coastal erosion prevention. In this experimental study, erosion geometry and wave reflection coefficients were determined for normal and stormy incident waves, with and without artificial seaweed. The coastline of beaches without artificial vegetation was observed to retreat, and the longshore bar height increased in normal and stormy conditions. Through the introduction of artificial seaweed (of widths 0.8 m, and 1.6 m), the coastline was found to advance in the offshore direction due to material deposition. From these results, it is shown that artificial seaweed alters the cross-section of beaches, such that it is possible to prevent coastline erosion.

• KCID journal
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• v.19 no.1
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• pp.3-18
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• 2012

In recent years, as environmental problems have become great concerns among many people, th loss of beach sand has become one of the highly controversial issue. Major reasons for the beach erosion within the cases of West Coast can be classified as: 1) erosion at Unyeo, Baeksajang beaches are caused by the wave refraction according to the large-scale sand dredging, 2) erosion at Kkotji, Baeksajang, and Unyeo beaches are caused by large-scale embankment construction and the coastal road construction, and 3) erosion at Chollipo and Hakampo beaches are caused by construction of small ports. Erosion in the west coast of Korea coast beach erosion control measures, include groin, zeotube, terraced stone, jetty groin, and beach nourishment. Erosion control measures initially installed to prevent erosion showed a positive effect. However, if there is no continuous source of sand, the effect of measures is fewness.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.920-926
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• 2019

In this study, we analyzed the erosion variation of beach area at Haeundae Beach after coastal improvement project using video monitoring system operated by the Coastal Erosion Monitoring (Ministry of Oceans and Fisheries). Haeundae Beach was well maintained and stabilized following large scale nourishment through coastal improvement project despite of seasonal fluctuations. However, multiple typhoons over the last two years caused beach stabilization patterns and seasonal fluctuations to lost equilibrium, resulting in rapid erosion. In particular, the sandy beach was eroded by typhoon Solic and Kongray in 2018 and failed to recover beach area in winter by seasonal fluctuations. And due to multiple typhoons in 2019, the beach area was reduced 9.5 % (12,607 ㎡) year-on-year. According to analyze the observed wave and beach area data in Haeundae, the tendency of erosion and sedimentation was influenced by seasonal incident wave direction for each section(west, center and east part). Therefore, to identify the causes of decreasing seasonal fluctuation characteristics and continuous erosion, hereafter, more precise monitoring of different factors are needed, such as the crest heights of submerged breakwater and its loss of function, and sand leakage to the outside around submerged breakwater.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.3
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• pp.216-222
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• 2010

The structural methods used to protect coastal erosion are usually very expensive in construction as well as in spending on maintaining the structures from damage. Those structures like embankments, breakwaters, jetties etc. are commonly constructed with concretes (rigid methods) to protect coastal erosion. But those rigid methods are not effective always, because the wave energy and impact force on the structures could not be effectively reduced by those methods. For avoiding sediment erosion on coastal areas by the way of reducing wave energy, a flexible breakwater is introduced which will reduce energy and protect coastline economically and environmentally. The flexible device is a combination of flexible wire nets and stack of rings made of used vehicle tires and soft blades on surfaces. This flexible wire net is placed in between two stacks of rings. The stack of rings is mainly used to hold the flexible wire nets and the flexible wire net is mainly used to reduce wave energy and helps to deposit sediments in coastal area. For a field experiment study, the above-mentioned flexible breakwater of coastal protection has been set up at the Shuang-Chun coastal area in Tainan County since June 10, 2009. The length of the flexible device is 50.0 meters and the height is 2.0 meters. The function of the device has been examined by Typhoon Linfa during June 19~22, 2009 and by Typhoon Morakot during August 6~10, 2009. The result shows that the flexible breakwater has effectively trapped sediments and let them deposit on coastal. The depth of sediment deposition around the device was about 0.5 to 0.8 meters.

• Journal of the Korean GEO-environmental Society
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• v.3 no.2
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• pp.71-79
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• 2002

A numerical simulation has been performed on the generation of the coastal cliff which lies as the distinct boundary between the beach and the hinterland. As a result of storm surge, it is known that the steeper the initial beach slope, the larger the generation of the coastal cliff. The rise of water level added the mean water level accelerates the generation of the coastal cliff. In addition, the longshore distribution of the incident wave height is one factor that bring about the generation of the non-uniform coastal cliff in longshore direction. Therefore this study will be able to use for expecting the formation and erosion of coastal cliff in sand beach.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.2
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• pp.95-105
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• 2020

In order to promote efficient coastal management, it is important to continuously monitor the characteristics of the terrain, which are changed by various factors. In this study, time series UAV images were taken of Gyeokpo beach. And the standard deviation of ±11cm(X), ±10cm(Y), and ±15cm(Z) was obtained as a result of comparing with the VRS measurement performance for UAV position accuracy evaluation. Therefore, it was confirmed that the tolerance of the digital map work rule was satisfied. In addition, as a result of monitoring the erosion and sedimentation changes using the DSM(digital surface model) constructed through UAV images, an average of 0.01 m deposition occurred between June 2018 and December 2018, and in December 2018 and June 2019. It was analyzed that 0.03m of erosion occurred. Therefore, 0.02m of erosion occurred between June 2018 and June 2019. From the topographical change analysis results, the area of erosion and sediment height was analyzed, and the area of erosion and sedimentation was widely distributed in the ±0.5m section. If we continuously monitor the topographical changes in the coastal regions by using the 3D terrain modeling results using the time series UAV images presented in this study, we can support the coastal management tasks such as supplement or dredging of sand.