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Choi, H.-J.; Cho, S.-J.; Kim, T.H., and Nam, J., 2023. Assessment of Marine Use Zones (MUZs) in the spatial planning of Jeonbuk sea waters (southwestern Korean peninsula). In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 338-342. Charlotte (North Carolina), ISSN 0749-0208. The Korean government has adopted marine spatial planning as a new policy tool for integrated marine space management and has designated nine Marine Use Zones (MUZs) on all sea water areas. To designate MUZs, it is necessary to conduct a Marine Spatial Assessment (MSA) to identify the scope and level of core activities and spatial conflict potential between MUZs. This paper covers the MSA method for Jeonbuk waters and discusses the limitations and implications of the current MSA for the effective designation of the MUZs. Marine spatial planning (MSP) for Jeonbuk considers various demands for use and development, such as leisure, marine energy development, and the Saemangeum construction project, as well as the protection of excellent ecology and scenery, such as tidal flats and islands. Thus, MSA was conducted to designate MUZs that reflect these regional characteristics well according to relevant guidelines. The MSA procedure consists of preparation, data collection and processing, characteristic evaluation, and conflict analysis. Specifically, data on marine use and those pertaining to resources of the target sea were collected and transformed into grid-based (3'x3') GIS data. Based on these results, the MUZs in the target area were designated and managed. This study had several limitations and implications. First, there were difficulties in defining core activities according to the accessibility and availability of input data for MSA. Hence, methods and techniques such as data fusion and their spatial interpolation are required to overcome these limitations. Second, a future study (e.g., ecosystem services) should be conducted to quantitatively evaluate and visualize the value of benefits provided by marine ecosystems. Third, location-based AIS and fishing boat data are likely to prove useful for identifying the characteristics of dynamic activities such as fishing and shipping. Finally, it is necessary to apply simulation model to reflect not only the recent behavior pertaining to the use of marine space and resources, but also potential future behavior relating to MUZs. [ABSTRACT FROM AUTHOR]

Yuk, J.-H.; Kim, K.O.; Jung, K.T., and Choi, B.H., 2016. Swell prediction for the Korean coast. The accurate prediction of abnormally high waves occurring in the East Sea during winter is important in terms of the prevention of coastal disasters along the east Korean coast. This study attempts to hindcast the abnormally high swell wave events that occurred in October 2006 and February 2008 using the unstructured grid wave model UnSWAN with high-resolution reanalysis data from the European Centre for Medium-Range Weather Forecasts as meteorological inputs. The model used in this study incorporates an additional weighting factor for the relative wave-number in dissipation source term to improve swell propagation and wave period. Wave heights and periods are well reproduced compared with the observational data. Examination of the meteorological data and model results shows that the abnormally high waves in October 2006 were induced by the overlap of a swell wave and a wind-generated wave with nearly the same heading directions; the wave generated in February 2008 was, however, induced by the swell that propagated over very long distances from the northeastern area of the East (Japan) Sea due to enhanced atmospheric low pressure. Use of the reanalysis meteorological data and a wave model equipped with a weighting factor is found to be useful in identifying the generation mechanisms as well as reasonable estimates of abnormally high wave events. [ABSTRACT FROM AUTHOR]

Kwon, Y.; Choi, J., and Kwon, J., 2020. Simulation of storm surge due to the change of typhoon moving speed in the south coast of Korea Peninsula. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 1467-1472. Coconut Creek (Florida), ISSN 0749-0208. Typhoon-induced storm surges can cause severe damage on the Korean peninsula, where typhoons typically occur two or three times per year with 80 % of the total typhoons occurring during summer. In the case of the 14th typhoon MAEMI (0314) in 2013, a storm surge of 2.1 m was observed at the southern coast of the Korean peninsula, and the total property damage was USD 4.3 billion along with 132 casualties. In the case of 16th typhoon CHABA (1618) in 2016, a storm surge of 1.1 m was observed at the southern coast of the Korean peninsula, and the total property damage was USD 18.3 million along with seven casualties. Therefore, accurate prediction of storm surge heights and peak durations of typhoon surges occurring in the vicinity of the Korean peninsula is important for minimizing this damage. Therefore, in this study, storm surge numerical experiments were performed using the Delft3D model with the typhoon parameter model results as weather field input data. The experimental results matched well with the recorded observations at the weather stations considered in this study. Moreover, the experimental results showed that as the typhoon moves faster, the peak duration becomes shorter, and the maximum surge height decreases or increases depending on the local geography. [ABSTRACT FROM AUTHOR]

The climate change characteristics and adaptation abilities of the offshore East China Sea area are very important issues against the backdrop of the Maritime and Polar Silk Roads strategy. Based on meteorological observation data and reanalysis data, the spatial distribution and temporal variation characteristics of sea surface temperature (SST), sea surface salinity (SSS) and winds in the offshore East China Sea area were analyzed. From 1979 to 2017, the offshore average SST increased by 0.18°C/10 a as a whole. The average SSS showed an interdecadal cycle from 1980 to 2017 with a peak in 2005 (34.54 g/kg) and a trough in 1995 (34.26 g/kg). The lowest offshore SSS was 34.0 g/kg in the southern Korean Peninsula and the southern Taiwan Strait, while the highest offshore SSS was 34.8 g/kg in the low-latitude Pacific offshore area. The climatic characteristics annual accumulated gale days, annual local maximum wind speed, absolute maximum wind speed and average wind speed from 1971 to 2017 were analyzed, which showed that the influence of gales on Zhejiang was more serious than their influence on the other provinces in East China. In addition, decision-making strategies for climate change adaptation are discussed to provide a scientific reference for controlling the risks of climate change to the East China coastal zone and the Maritime Silk Road strategy. [ABSTRACT FROM AUTHOR]

Park, Y.H.; Oh, Y.-M.; Ahn, S.M.; Han, T.H.; Kim, Y.-T.; Suh, K.-D., and Won, D., 2019. Development of a new concrete armor unit for high waves. Journal of Coastal Research, 35(3), 719–728. Coconut Creek (Florida), ISSN 0749-0208. Hundreds of new concrete armor units (CAUs) have been developed since 1950, but only a few have been used because of their low price and familiarity. Because the design wave height has been increasing as a result of climate change, the Korean government decided to develop a new CAU for protection against high waves. Therefore, a new research project to develop a new CAU that considers stability, structural strength, economic feasibility, casting efficiency, and constructability was started. The new CAU was called Chi Block. The hydraulic stability achieved a Hudson stability coefficient of more than 13 at a significant wave height of 10 m by adopting a conservative approach. Chi Block can be installed in both uniform and random placements and can be used as an overlay for repair. A new placement for Chi Block was invented, and it features the advantage of functioning like a 1.5 layer. Although a single layer generally has a higher overtopping rate than a double layer, Chi Block, on uniform placement, has a performance near that of the Tetrapod. [ABSTRACT FROM AUTHOR]

Kim, K.O.; Lim, H.S.; Choi, J.-Y., and Kim, S.-S., 2018. Abnormally high waves induced by Typhoon Vongfong along the eastern coast of the Korean Peninsula. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 906–910. Coconut Creek (Florida), ISSN 0749-0208. Korean Peninsula has become vulnerable to increasingly frequent and strong typhoons approaching through the Yellow Sea and the East Sea. The typhoons are one of the threats to the coastal areas causing direct damages with increasing sea surface temperature and sea level rise due to global warming. The damages caused by waves and swells generated by anti-cyclonic winds from the recent typhoons prompted the Korean government to initiate two projects, development of coastal erosion control technology and investigation of large swell waves and rip currents for the southern and eastern coasts. During the typhoon Vongfong (2014), the highest wave recorded at Uljin (6 m) was 80 minutes after the highest wave at Samcheok (4.6 m), which is located further northwest. The measurement of abnormally high waves propagated both from East Sea and along the northern coast was unprecedented. The observed data at Busan, Uljin and Samcheok and a Simulation WAves Nearshore (SWAN) model were applied to analyze the unusually high waves on the eastern coast of Korea. The analyzed results showed that abnormally high waves at Uljin induced by typhoon Vongfong could be generated by the resonance effect that merged with lower energy waves propagated from the East Sea and higher energy waves propagated along the eastern coast from northwest, Samcheok. [ABSTRACT FROM AUTHOR]

Kwon, J.-I.; Choi, J.-W.; Lee, J.-C.; Min, I.-K., and Park, K.-S., 2018. Spatio-temporal characteristics of storm surge events in the Korean Peninsula. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 891–895. Coconut Creek (Florida), ISSN 0749-0208. A total of 188 typhoons (about 3.2 annually) have affected the Korean Peninsula (KP) from 1959 to 2016 by the Korea Meteorological Administration (KMA). This study investigated the spatio-temporal characteristics of storm surge events in the KP for 135 typhoons using data from tidal gauges maintained by the Korea Hydrographic and Oceanographic Agency (KHOA). Because about 50 typhoons have made landfall on the south and west coasts of KP, storm surge records are concentrated along these coasts. For example, the highest number of storm surge observation records (35) came from the city of Mokpo on the southwestern coast. The highest recorded storm surge height was 2.1 m at Masan, on the south coast, during typhoon MAEMI (0314); the storm surge occurred during high tide, causing tremendous damage. A total of 239 surge heights over 0.5 m were recorded in the KP, and maximum storm surge heights over 1 m were recorded 21 times. About 31 % of storm surges occurred in the tidal flood phase, based on limited records. When typhoon BOLAVEN moved along the west coast in 2015, most tidal gauges showed that negative surges occurred when BOLAVEN approached, a smaller surge occurred as the typhoon's center neared the stations, then the maximum surge height was recorded after BOLAVEN passed by. [ABSTRACT FROM AUTHOR]

Heo, K.-Y.; Choi, J.-Y.; Park, K.-S.; Kwon, J.-I.; Min, I.-K., and Ha, T., 2018. Explosively developing extratropical cyclone associated with the high wind-waves along the east coast of Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 716–720. Coconut Creek (Florida), ISSN 0749-0208. An extreme extratropical cyclone struck the northern part of Korea on May 3, 2016 causing significant damage to property on the land due to extreme winds and abnormal high waves in coastal area. The meteorological composite fields for the cyclone show a strong surface wind velocity (up to 45 m s−1) during its mature stage. This study investigated the development mechanisms of an explosive cyclone through numerical simulation and sensitivity experiments using the Advanced Research version of the Weather Research and Forecasting (WRF-ARW) model. The trigger mechanism for the explosive cyclogenesis is the strong baroclinic instability and temperature advection associated with upper-level cut-off low and the interaction of potential vorticity (PV) anomalies between the lower- and upper-level. The efficient placement of the high- and low-level jets forms a favorable environment for its development and transportation of water vapor and the instability energy into the cyclone. The sea-state wave simulation around the Korean Peninsula is obtained using the wave model WAVEWATCHIII (WW3) forced by the 10-m above ground level wind field from the WRF-ARW simulations. The significant wave height and peak wave direction were simulated and wave distribution was analyzed by comparing the removal of the upper-level PV with the doubled. The numerical results using the doubled upper-level PV reproduced well generation of high waves around the Korean Peninsula while not the removal of the upper-level PV. [ABSTRACT FROM AUTHOR]

Chang, J.-I. and Yoon, S., 2017. Assessing the economic value of beach restoration: Case of Song-do Beach, Korea. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 6-10. Coconut Creek (Florida), ISSN 0749-0208. In 1913, Song-do beach in Busan was declared the first official public beach in Korea. However, since the 1990s, erosion levels have increased and in 2003, Typhoon Maemi caused extensive damage to the beach and coastal road. It has taken several public restoration projects to restore the capacity of recreation and coastal protection. This study aims to analyze the economic benefits of the Song-do beach restoration by verifying benefit factors of the coastal erosion control and beach restoration, such as recreational services and various coastal ecosystem services. We applied a non-market valuation method, contingent valuation method, which allows the measuring of individual willingness to pay for the beach restoration project. The annual economic value of the restoration is estimated at 2,542 KRW (2.5 USD) per household and its total economic benefit is about 234.7 billion KRW (229.8 million USD). These findings have key implications for policymakers with quantitative information and decision makers related to beach restoration policies. [ABSTRACT FROM AUTHOR]

Kim, H.; Lee, S.B., and Min, K.S., 2017. Shoreline change analysis using airborne LiDAR bathymetry for coastal monitoring. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 269-273. Coconut Creek (Florida), ISSN 0749-0208. Shoreline is commonly defined as the boundary between land and sea. As a consequence of global climate changes and human interventions, shoreline is constantly changing by erosion and accretion. Korea is also faced with the coastal erosion problem. Therefore, the coastal monitoring method needs to quantitatively analyze the shoreline locations and differences in past and present. For this, our research for coastal monitoring is to adopt the quantitative analysis of shoreline change using airborne bathymetry LiDAR. Bathymetry data is useful for coastal monitoring, since the water depth provide geospatial information of 3D point cloud data, including the shallow water as well as the near-shore. In this study case, bathymetry data was collected by CZMIL in 2013 at Gyeongpo and Wonpyeong beach. Topography data collected by ALTM in 2010 was used to check trend of shoreline change at the same sites. In order to extract shoreline position from the LiDAR data, the shoreline definition is referenced as AHHW (Approximate Highest High Water). As a result, East coast has eroded about 347 m2 of Gyeongpo beach and about 23819.5 m2 of Wonpyeong beach. From this analysis, the average annual rate of erosion is 1.6 m per year. Shoreline change at East coast resulted in a landward retreat by 5 m at the last four years. [ABSTRACT FROM AUTHOR]

Chang, J.I. and Yoon, S., 2016. The Economic Benefit of Coastal Erosion Control in Korea. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 1317 - 1321. Coconut Creek (Florida), ISSN 0749-0208. The Korean coastal zone is regarded as a highly valuable environmental asset and provides important space for human life. Korean counties with a coastline have a deep interest in finding the most appropriate and sustainable management policy for their coastal resources and ecosystems. Korean coastal zone is now experiencing environmental pressure and is under threat from a diverse range of destructive forces. Thus, this study analyzes the economic benefits of Korea's coastal erosion control project (CECP). The main results of the study are as follows. (1) First, the study identifies the benefit factors of coastal erosion control, such as damage control services, recreational services, and other coastal ecosystem services. (2) Second, this study assesses the economic benefits of the CECP in Korea by applying choice experiment, a non-market valuation method. The annual benefit is estimated at 31,824 KRW (26.56 USD) per household, and the total annual economic benefit of the CECP is estimated at 587.7 billion KRW (490.8 million USD). The findings provide policymakers with a useful methodological framework and quantitative information for decision making on costal management policy. [ABSTRACT FROM AUTHOR]

Choi, J.; Roh, M., and Kim, Y.T., 2016. A Laboratory Experiment on beach profile evolution induced by two wave conditions dominated in the Haeundae Coast of Korea. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 1327 - 1331. Coconut Creek (Florida), ISSN 0749-0208. A laboratory experiment was performed by using the scaled-down conditions ( i.e., 1/10) of the two dominant waves (i.e, a storm wave and a normal wave) obtained from the statistical analysis of wave data measured at the Haeundae coast during 3 years. The storm and normal waves did alternately evolve the beach profile from a constant slope and each of the wave conditions was maintained to reach its quasi-equilibrium state. The observation was conducted in the surf zone and the swash zone during the alternation of the 1-hr storm-erosion condition and the 2-hr normal-accretive condition. The storm-erosion condition generated the longshore bar-crest and trough and the steep berm, and the normal-accretion condition reduced the bar and trough. The subsequent quasi-equilibrium beach profile was reasonably agreed to the beach profile of the Haeundae beach. [ABSTRACT FROM AUTHOR]

Jung, Y.-H.; Yoon, K.-T.; Shim, W.-J., and Park, H.-S., 2015. Short-term variation of the macrobenthic fauna structure on rocky shores after the Hebei Spirit oil spill, west coast of Korea. This study was conducted to determine the initial response, such as ecological status, to the disturbance in macrobenthic fauna on a rocky shore after an oil spill. Sites polluted with oil spilled during the Hebei Spirit accident on December 7, 2007, showed continuous decreases in species of the Bivalvia class, including Lasaea undulata and Mytilus galloprovincialis, and no gastropods were observed. In addition, at polluted sites, the cold-water barnacle Chthamalus challengeri and the common periwinkle were present in low densities, whereas they appeared relatively stable at control sites. In this study, the macrobenthic community structure was distinct between polluted sites and control sites because of differences in species composition and densities of dominant species. Therefore, it is believed that the oil spill accident could lead to mass mortalities of the major macrobenthic fauna in the study area, by smothering or reducing breeding activities or recruitment, and thereby altered rocky shore ecosystems. [ABSTRACT FROM AUTHOR]

Choi, J.W.; Kwon, J.I.; Heo, K.Y., and Choi, J.Y., 2020. Hindcasting of search and rescue cases using the trajectory model based on KOOS (Korea Operational Oceanographic System). In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 900–904. Coconut Creek (Florida), ISSN 0749-0208. The most important consideration for search and rescue (SAR) is to accurately predict the trajectory of missing persons or vessels to secure a search area and the golden time for rescuing survivors. The SAR modeling system of the Korea Operational Oceanographic System (KOOS) is directly linked to the Weather Research and Forecasting model (WRF), the Modelo Hidrodinâmico (MOHID), and the Modular Ocean Model (MOM5). The SAR prediction result produced by KOOS is provided to the Korea Coast Guard, which is responsible for SAR missions in Korea. In this study, numerical model results were evaluated using actual accident case and the trajectory data of drift buoys. Prediction accuracy was explored using 1) two different horizontal resolutions (300 m and 4 km) of the MOHID and 2) two different time resolutions (MOHID: 1 h; MOM5: 1 day) at the same horizontal resolution (4 km). The analysis of drift prediction accuracy showed that prediction accuracy was relatively high for the MOHID at a resolution of 300 m, which was a higher horizontal resolution close to the coast. This provided more accurate tidal current results. The time resolution in the offshore region affected ocean currents, and prediction performance was relatively high for the MOHID at a resolution of 1 h. Based on these results, it was found that securing high-resolution data in time and space is essential for improving the performance of drift prediction in adjacent seas in the Korean Peninsula. [ABSTRACT FROM AUTHOR]

Cho, J.H.; Son, Y.B.; Shin D.-H.; Moh, T.J.; Jang S.; Lee S.Y.; Lim D.G., and Kum B.C., 2020. Changes in underwater visibility due to turbidity associated with Typhoon Soulik. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 417-421. Coconut Creek (Florida), ISSN 0749-0208. Changes of visibility in the water column off the southern coast of Korea due to the effects of Typhoon Soulik (Aug. 22–23, 2018; 955 hPa; maximum wind speed, 40 m/s) were investigated. The beam attenuation coefficient (BAC) was measured using a transmissometer (C-Star; Wet Labs, Inc.), and visibility range was calculated using the conversion method employed by the US Navy. For comparison and verification of the data, a conductivity–depth–temperature (CTD) probe (SBE19 Plus; Sea-Bird Scientific) equipped with optical backscatter and fluorescence sensors was deployed simultaneously with the transmissometer. The Secchi depth was also estimated during each cast to improve accuracy. The Secchi depth deviated by up to 20% from the calculated visibility range. Additionally, during continuous observation of BAC from the seafloor upward, a light source (color temperature: 6,500 K) was installed on a 5-m bar with length markings, and a video camera recorded changes in visibility. Daily Geostationary Ocean Color Imager (GOCI) satellite data were used to identify changes in surface visibility in the study area. Before the typhoon, the visibility in the water column was in the range 25–30 m. Near the seafloor, visibility approached 0 m due to a 3–6-m turbidity current. The visibility distance was significantly shorter in the bottom layers based on video images. Four days after Typhoon Soulik had passed over the Korean Peninsula, the visibility was in the range 2.6–9.0 m in the upper layers of the water column, increasing gradually to 11 m in the middle layers. The size of the turbid bottom current did not differ significantly between observations before and after the typhoon. Surface visibility calculated from satellite data also decreased by 20–30% compared to that before the typhoon. [ABSTRACT FROM AUTHOR]