• Proceedings of the Korean Society of Marine Engineers Conference
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.205-206
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• 2006

The surges caused by the typhoon of Korea are analysed in Kwangyang Bay. The deviations of the high water level were $74{\sim}185cm$ and the maximum deviations of the water level (maximum surges) were $151{\sim}240cm$ in Kwangyang Bay during the typhoon. The major parameters of the maximum deviations of the water level are as follows : Analysis shows that the pressure drop increased the sea level by $43{\sim}59cm$, the flood of the Sumjin River by $4{\sim}5cm$ and the external surge propagation and wind setup by $97{\sim}192cm$.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• 제27권4호
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• pp.293-302
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• 1991

The anomalous sea level deviation or storm surge caused by the typhoon Thelma in 1987 are studied analysing tidal observation data at 7 stations in the south coast of Korean peninsula. The surges are calculated by subtracting the predicted tidal height from the observed tidal record. The tidal deviation at these stations along the coast are discussed in association with meteorological data. The sea level anomalies are studied by means of the empirical orthogonal function (EOF) analysis and the fast fourier transform (FFT) method. The results of analysis suggest that the peak value of surges are higher at the tidal stations in semi-enclosed bay and in long narrow channel than at the ones facing with the open sea. From the result of EOF analysis, the temporal and spatial fluctuations of storm surge can be described by the first EOF mode, which explains 63% of the total variances during the passage of typhoon Thelma. The deviation of storm surge in the studied areas indicates bi-modal peak during the passage of typhoon Thelma. From the results of FFT spectrum analysis, the peak of energy of autospectrum for surge, atmospheric pressure, and wind stress appeared at low frequency fluctuations band of 0.008-0.076 cph over the 4 stations. Auto-correlation function of surge showed periodicity, while that of atmospheric pressure and wind stress indicates no periodicity. The result of FFT analysis shows that the typhoon surges are related chiefly with the change of atmospheric pressure in an open bay (Cheju Harbor), but with the wind stress in a semi-enclosed bay (Yeosu Harbor).

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제31권1호
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• pp.1-8
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• 2019

This research mainly focuses on examining the applicability of the deterministic model SLOSH (Sea, Lake and Overland Surges from Hurricanes) on Seas covering South Korea. Also, a simple bathtub approach which estimates coastal inundation area is validated as a first step of estimating effects of sea-level rise on the coastal cities of South Korea according to climate change. Firstly, the typhoon-induced surges are obtained from the model SLOSH by adopting historical typhoons MAEMI (0314) and BOLAVEN (1215). The results are compared to observational, typhoon-induced surge heights at several tidal stations. The coastal inundation area is estimated by comparing the maximum envelop of waves (MEOW) and the elevation of coastal land. It reproduces well the inundation area. It can be seen that this research gained applicability for estimating further potential coastal inundation with climate changes.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.574-578
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• 2006

Tidal amplification by construction of the sea-dike and sea-walls had been detected not only near Mokpo Harbor but also at Chungkye Bay which is connected with Mokpo Harbor by a narrow channel. This brings about increase of tidal flat area and in particular increase of surge-wave combined runup during storms. The purpose of this study is to examine an efficient operational model that can be used by civil defense agencies for real-time prediction and fast warnings on wind waves and storm surges. Instead of using commercialized wave models such as WAM, SWAN, the wind waves are simulated by using a new concept of wavelength modulation to enhance broader application of the hyperbolic wave model of the mild-slope equation type. Furthermore, The predicting system is composed of easy and economical tools for inputting depth data of complex bathymetry and enormous tidal flats such as Mokpo coastal zone. The method is applied to Chungkye Bay, and possible inundation features at Mokpo Harbor are analyzed.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제32권5호
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• pp.351-362
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• 2020

Numerical simulations of the storm surge and waves induced by the Typhoon Maemi incident on the south sea of Korea in 2003 are performed using the JMA-MSM forecast weather field, NCEP-CFSR reanalysis weather field, ECMWF-ERA5 reanalysis weather field, and the pressure and wind fields obtained using the best track information provided by JTWC. The calculated surge heights are compared with the time history observed at harbours along the coasts of Korea. For the waves occurring coincidentally with the storm surges the calculated significant wave heights are compared with the measured data. Based on the comparison of surge and wave heights the assessment of the reliability of various weather fields is performed. As a result the JMA-MSM weather fields gives the highest reliability, and the weather field obtained using JTWC best track information gives also relatively good agreement. The ECMWF-ERA5 gives in general surge and wave heights weaker than the measured. The reliability of NCEP-CFSR turns out to be the worst for this special case of Typhoon Maemi. Based on the results of this study it is found that the reliable weather fields are essential for the accurate simulation of storm surges and waves.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제33권5호
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• pp.187-194
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• 2021

The damage caused by typhoons is gradually increasing due to the climate change recently. Hence, many studies have been conducted over a long period of time on various factors that determine the characteristics of storm surge, and most of relationships have been discovered. Because storm surge is complexly determined by various factors, it often show different results and draw different conclusions. For this reason, this study was conducted to understand the various characteristics of storm surge caused by changes in the forward speed of typhoons. This study was carried out with a numerical model, and the effect of forward speed could be analyzed by simplifying other factors as much as possible. When forward speed is increased, storm surges caused by typhoons tended to increase gradually. The storm surge showed a wide and gentle increase at a slow speed, but a narrow and steep one at a fast speed. In the case of the same forward speed, it was found that the storm surge was significantly influenced by the water depth of actual sea area. It was confirmed that the change in forward speed after passing Jeju Island did not significant affect on the storm surge in the south coast of Korea.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제24권3호
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• pp.166-178
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• 2012

In order to simulate storm surge for the west coast, complex physics of asymmetrical typhoon wind vortex, tide and wave are simultaneously incorporated on a fine finite element mesh extended to the North Western Pacific sea. Asymmetrical vortex based on maximum wind radii for each quadrant by JTWC's best tracks are input in pADCIRC and wave stress is accounted by dynamic coupling with unSWAN. Computations performed on parallel clusters. In hindcasting simulation of typhoon Kompasu(1007), model results of wave characteristic are very close with the observed data at Ieo island, and sea surface records at major tidal stations are reproduced with satisfaction when typhoon is approaching to the coast. It is obvious that increasing of local storm surges can be found by introducing asymmetrical vortex. Thus this approach can be satisfactorily applied in coastal hazard management against to storm surge inundation on low level area and major harbor facilities.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제24권5호
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• pp.352-365
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• 2012

A primary study on the rapid modeling of storm surge, which is one of typical coastal disasters, for immediate forecasting in conjunction with typhoon advisories is done and tested for the typhoons Bolaven, Tembin and Sanba which attacked to Korean Peninsula on August and September in this year 2012. Semi automatic rapid computations according to JTWC typhoon advisories were performed and uploaded to the web by models SLOSH in PC and ADCIRC in parallel clusters with 64 cores having 57k nodes encompassing the North-Western Pacific region. It only takes 1 and 2 hours from taking advisory to web uploading, respectively. By comparison with observed water surface elevations for the major tidal stations after Bolaven attack it shows within RMS error of 0.17~0.19 m for surge heights and only deviates 1 hour of peak surge time in ADCIRC model. Thus it is concluded that this approach provides a frame of near real-time immediate forecasting of storm surges with satisfactions.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제12권2호
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• pp.255-263
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• 1992

A numerical simulation using the Boundary Element Method is performed for investigating the seiche in the Mukho harbor. The range of the incident waves period is from 7 seconds to 10 minutes, which these surface waves usually may be found in cases of the swell and the long period storm surges caused by storm winds. It is found that the seiche may be occurred by resonating with the incident waves of which the periods are about 11 seconds and 3 minutes. The numerical method was verified by the hydraulic model experiment data which had performed before. Numerical results for the seiche in the Mukho harbor show good agreements with the field observations, so that this research may be useful to estimate harbor calmness in a harbor and the harbor planning.

• Journal of Korea Multimedia Society
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• 제15권2호
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• pp.258-265
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• 2012

Our country is suffering from many human victims and property damages caused to occur great and small tidal waves in southern areas every year. Even though there were progressing many researches for storm surges, it was required more researches for detection of tidal wave and prevention system of its which can be applied in practical living fields. In this paper, we propose the disaster prevention system that can approximately detect a dangerousness of coast flooding and number of overtopping per time based on images of CCTV considering actual field application. And if it is detected a hazard of flooding of coast, the proposed detection system for tidal wave based GIS is quickly informed the areas of flooding to manager. The analyzing results of CCTV image of this proposed are derived from difference images between photos of fine day and photos or videos which are taken for the typhoon which is called "DIANMU" at our laboratory.