• Journal of Ocean Engineering and Technology
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• v.26 no.1
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• pp.47-53
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• 2012

A coastal flood area was predicted using the empirical superposition of the typhoon surge level and typhoon wave height along the Busan coastal area. The historical typhoon damages were reviewed, and the coastal topography was measured using VRS-GPS. A FEMA formula was applied to estimate the coastal flood area in a typhoon case when the measured and predicted data of typhoon waves are not available. The results in the area of Haeundae beach and Gwangalli beach were verified using the flood area data from the case of Typhoon Maemi (2003). If a Hurricane Katrina class typhoon were to pass through the Maemi trajectory, the areathat would be flooded along theBusan coastal area was predicted and compared with the results of the Maemi case. Because of the lack of ocean environment data such as data for the sea level, waves, bathymetry, wind, pressure, etc., it is hard to improve the prediction accuracy for the coastal flood area in the typhoon case, which could be reflected in the policy to mitigate a typhoon's impact. This paper discusses the kinds of ocean environment information that is needed to predict a typhoon's impact with better accuracy.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.5
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• pp.411-420
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• 1998

To estimate the dispersion coefficients in a coastal area with complex topography, several schemes using empirical equations expressed with and in lateral and vertical directions, respectively have been examined. Estimation results using these equations and meteorological data obtained from SODAR system were compared' with previously measured dispersion coefficients in other coastal areas. Validations of estimation results have been performed by comparing the measured concentrations with predicted ones empolying in Boryung coastal area. Important conclusions were drawn as follows; (1) Variations of lateral and vertical wind direction revealed different height dependency in upper and lower mixed boundary layer. (2) Because of turbulent constraint effect by large water body in a coastal region, the lateral and the vertical dispersion coefficients were smaller than those of P-G system. (3) As a result of examining the performance measure of these schemes through checking of coincidence between measured and predicted concentrations, vertical dispersion coefficients were smaller than those of P-G system, and the Cramer scheme was found to be more appropriate rather than others in the coastal area surrounding Boryung power plant.

• Korean System Dynamics Review
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• v.15 no.3
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• pp.81-104
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• 2014

This study aimed to suggest the directions for the landscape protection of Sindu-ri coastal dune based on its ecological system. The study investigated ecological systems of the coastal dune followed by damage causes of coastal dune according to the land use change, and landscape value of coastal dune in the study area. In order to construct causal-effect feedback loop, systems thinking was performed. Result of this study showed that the area of coastal dune and the amount of sand are maintained by the interaction with sand beach while they are affected by wind direction, wind speed, and dune plants. It was also found that the changes of land use pattern, increasing commercial area, and planted windbreak forest damaged to the coastal dune. In addition, size of coastal dune and growing number of dune plants increased landscape value of coastal dune and tourist draw. However increasing tourists have constantly affected land use changes and have damaged to coastal dune area. In sum, planning for land use regulation, rest-year system areas, promotion and education for coastal dune, dune plants protection, and windbreak management should be taken into account for landscape protection in coastal dune.

• Journal of Environmental Science International
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• v.17 no.3
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• pp.269-273
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• 2008

The objective of this study was to evaluate the relationship between nutrients and phytoplankton. This study was done by the comparison to two costal areas Mokpo, which inflow fresh water, and Wando. In August, salinity of the sea water decreased by 3.5-4.5%o in Mokpo coastal area, but was not nearly decreased in Wando coastal area. This suggests a lot of fresh water inflow in Mokpo coastal area. DIN and DIP were decreased by water temperature increasing in Wando. However, in Mokpo, DIN and DIP were increased greatly during the summer season. Nitrogen was limited to a 10 NIP ratio especially during the summer season in Wando coastal area while phosphorus in Mokpo coastal area was limited with over 28 N/P ratio in all the seasons. Coefficient of determination$(r^2)$ between DIP and Chl.-a was 0.91 in Mokpo coastal area. On the other hand, Coefficient of determination$(r^2)$ between Chl.-a and DIN, DIP were 0.93 and 0.89, respectively, in Wando coastal area. These results suggest DIP in Mokpo and DIN and DIP in Wando might be limited at the increase of phytoplankton.

• Korean System Dynamics Review
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• v.16 no.1
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• pp.5-23
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• 2015

The purpose of this study is to analyze the land-use changes in the coastal areas using system dynamics modeling and to provide directions for effective management to maintain coastal dune areas. This research process consists of four steps: First, we built the basic model based on the causal loop diagram which was analyzed the land-use change of Sindu-ri Coastal Dune. Second, a time series land-use change map using Arc Map was established. Third, the validity of the basic model was tested. Finally, three simulations were performed for the cut over area($100,000m^2/y$, $150,000m^2/y$, $200,000m^2/y$) of windbreak for maintaining the coastal dune areas. Simulation of the basic model showed that the area of the coastal dune will be consistently decreased. Based on the simulation, if windbreak were cut down $150,000m^2/y$, windbreak area will be restored to the target area in 2019. This study has the limitation which the simulation is progressed with a limited variable: area. Therefore, the modeling of coastal dune should be reflected various variables in the further study.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.3
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• pp.149-156
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• 2000

This study presents an investigation of the changes that have occurred in the coastal ocean area of Kwangyang Bay located in the South Coastal region of Korea using remote sensing data based on Landsat Thematic Mapper (TM) multispectral digital data from 1988 and 1996. The coastal changes were detected using the digital histogram method and vector trace method. All the images were preprocessed, i.e. geometrically corrected, before the training set selection. when comparing the histograms of 7-band TM data, it was found that the band 5 image exhibited two critical Digital Number(DN) peaks, thereby indicating new coastal water and coastal land data. Based on this information, the coastal ocean area of the band 5 image was calculated using the vector tracing method supported by a CAD program. The result shows that the coastal ocean area decreased by about 5 % between 1988 to 1994. Accordingly, this gives a strong indication that the continuing land development will have a serious impact on the ecosystem of Kwangyang Bay.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.17-20
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• 2002

The environmental tracers of $^3$H and NO$_3$ were investigated in terms of vertical connections between basaltic aquifers and underlying sedimentary formations of Seoguipo formation that is not found in eastern coastal area and U formation. In western coastal area, $^3$H shows values less than 0.5TU In the wells completed in Seoguipo formation whereas it is greater than 2TU in other area. For the wells in western area, NO$_3$ concentrations are below background level though the nearby land uses are mainly agricultural. The groundwater heads are much lower in eastern coastal area than western area in spite that recharge rate of eastern area is 1.7 times higher than that of western area. The basaltic aquifer is thicker by 70m in eastern coastal area than in western coastal area, which is insufficient to explain much lower groundwater heads in eastern area. These hydrogeological characteristics suggest that for the basaltic aquifers, the Seoguipo formation acts as a lower boundary which could limit downward groundwater flow in basaltic aquifers whereas the U formation is unlikely.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.1
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• pp.1-15
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• 2004

Sea/land circulation system is a representative mesoscale local circulation system in coastal area. In this study, wind fields around coastal area. Pohang, which is affected by this system was investigated and its detailed characteristic analysis was carried out. The following can be found out from the numerical simulation. Generally, at nighttime mountain winds prevail and land breeze toward the coastal area was well simulated During daytime, valley wind and sea breeze was simulated in detail. Especially, as a result of analyzing the land breeze path, it could be found along the coastline as it flows out through low land coastal area. In order to investigate the accuracy of model results. wind speed, temperature and wind direction of continuous typical sea/land breeze occurrence day was compared with observation data. Analyzing the characteristics of local circulation system was very hard because of horizontally sparse observation data but from the above result, a numerical simulation using RAMS, which satisfies the spatial high resolution, will provide more accurate results.

• Journal of the korean society of oceanography
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• v.37 no.4
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• pp.212-223
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• 2002

Cochlodinium polykrikoides bloom in 1995 was studied with a focus on an unusual coastal environment in the South Sea of Korea. Data on temperature, salinity, and zooplankton biomass during 1965-1998 and nutrients during 1990-1998 and chlorophyll-a during 1995-1998 were used in this study. These data were obtained from the serial oceanographic observations in Korean waters carried out by the National Fisheries Research and Development Institute. In 1995 the C. polykrikoides bloom began in the coastal area around Narodo Island in August and consequently occurred to the whole coastal area of the South and East Seas of Korea. During June-October 1995, the coastal environment was unusual compared with the long-term means during 1965-1998. In June 1995, sea surface temperature was 1-2$^{\circ}C$ warmer than in other years in all coastal areas, while salinity was high only to the east of Jeju Island. In August 1995, a strong coastal front appeared inshore of a line between Jeju and Tsushima Islands. In particular, a strong coastal front which showed the characteristics of upwelling front occurred in the coastal area around Narodo and Sorido Islands, not only because of a strong intrusion of the Tsushima Warm Current but also because of the upwelling of cold bottom water. Salinity was low in the neighboring waters of western side of Jeju Island. Nutrients and chlorophyll-a were high in the inshore area between Narodo and Sorido Islands in 1995 in contrast with the other years and areas. Zooplankton showed an unusually high abundance in the coastal area in October 1995. We conclude that the Tsushima Warm Current strongly influenced the South Sea of Korea in 1995 and created strong upwelling front bordering cold upwelled water in the coastal area around Narodo and Sorido Islands. It leads us that these physical structures introduce the favorable environment for the development of C. polykrikoides blooms. We suggest that C. polykrikoides has a bio-physical tolerance of high shear and stress and prefers frontal and upwelling relaxed areas as its habitat. We also find that nutrients were not supplied to the coastal area from the offshore where a low salinity water mass with high nutrients appeared around Jeju Island. Because the strong upwelling front protect the reach of offshore low saline water mass. The main source of nutrients was the upwelled water mass in the coastal area of Wando-Narodo-Sorido.

• Journal of Environmental Science International
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• v.5 no.3
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• pp.277-284
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• 1996

The Characteristics of atmospheric flow and dispersion of air pollutants in the mountainous coastal area were studied using two-dimensional model by the combination of land-sea breezes and transport. The pollutants emitted into the simulated wind field in considering with the mesoscale local circulations. The typical effects of land-sea breezes and tophography of coastal area on the dispersion are discussed in detail, and the model is proved as an useful tool to pridict real time pollutant transport by the results of application studies in Pusan, Korea where the urbanized coastal area with mountainous topography. It was found that sulfur dioxide ($SO_2$) are differently transported and concentrated as going inland by the influence of the sea breeze with topographic changes. Key words : land-sea breezes, sulfur dioxide, dispersion, coastal area.