• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.4
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• pp.273-283
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• 2020

Numerical simulations of the storm surge and waves induced by the Typhoon Bolaven incident on the west sea of Korea in 2012 are performed using the JMA-MSM weather field provided by the Japan Meteorological Agency, and the calculated surge heights are compared with the time history observed at harbours along the various coasts of Korea. For the waves occurring coincidentally with the storm surges the calculated significant wave heights are compared with the data measured using the wave buoys operated by the Korea Hydrographic and Oceanographic Agency and the Korea Meteorological Administration. Additional simulations are also performed based on the pressure and wind fields obtained using the best track information provided by the Joint Typhoon Warning Center, and the calculated results are compared and analyzed. The waves and storm surges calculated using JMA-MSM wether field agree well with the observations because of the better reflection of the topography and the pre-background weather field. On the other hand, the calculated results based on the weather fields produced using the JTWC best track information show some limitations of the general trend of the variations of wave and surge heights. 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 Korea Water Resources Association
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• v.44 no.8
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• pp.601-617
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• 2011

In this study, the simulation and analysis for the inundation in a coastal urban area according to the storm surge height are carried out using a 2-D numerical model. The target area considered in this study is a part of the new town of Changwon City, Gyungsangnam-do and this area was extremely damaged due to the storm surge generated during the period of the typhoon "Maemi" in 2003. For the purpose of the verification of the numerical model applied in this study, the simulated results are compared and analyzed with the temporal storm surge heights observed at the tide station in Masan bay and inundation traces in an urban area. Moreover, in order to investigate the influence of super typhoons possible in the future, the results simulated with the storm surge heights increased 1.25 and 1.5 times compared with those observed during the period of typhoon "Maemi" are compared and analyzed.

• Atmosphere
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• v.17 no.1
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• pp.87-99
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• 2007

Simulation results of Asian Dust Aerosol Model (ADAM) for the period of April 7-9, 2006 were analyzed, comparing with observed PM10 data. ADAM simulated around ten times lower than on-site PM10 concentration in the source regions: Zhurihe, Tongliao, Yushe, Dalian and Huimin. As the result of this low concentration, transported amounts of Asian Dust were under-estimated as well. In order to quantify a forecasting accuracy, Bias and RMSE were calculated. Even though remarkably negative Biases and high RMSEs were observed, ADAM simulation had followed well up the time of dust outbreak and a transported path. However, the emission process to generate dust from source regions requires a great enhancement. The PM10 concentration at the surface reached up to $2,300{\mu}gm^{-3}$ at Baeknyoungdo and Seoul (Mt. Gwanak), up to $1,750{\mu}gm^{-3}$ at KGAWO about 18:00 LST in April 8, respectively; however, ADAM did not simulate the same result on its second peak. It is considered that traveling Asian dust might have been lagged over the Korean peninsula by the blocking of surface high pressure. Moreover, the current RDAPS's 30 km grid resolution (which ADAM adopts as the meteorological input data) might not adequately represent small-scale atmospheric motions below planetary boundary layer.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2006.09a
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• pp.173-176
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• 2006

• Journal of Korean Society of Disaster and Security
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• v.8 no.1
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• pp.39-46
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• 2015

This study is concerned with the estimation of fluctuation wind velocity spectrum and turbulence characteristics in the major cities reflecting the recent meteorological with typhoon wind velocity about 2003 (Maemi) 2010 (Kompasu) 2012 (Tembin). The purpose of this paper is to present spectral analysis for longitudinal component fluctuating velocity obtained by Monte Carlo Simulation method. In the processes of analysis, the longitudinal velocity spectrums are compared widely used spectrum models with horizontal wind velocity observations data obtained at Korea Meteorological Adminstration (KMA) and properties of the atmospheric air for typhoon fluctuating wind data are estimated to parameters with turbulency intensity, shear velocity, probability distribution and roughness length.

• Journal of Navigation and Port Research
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• v.31 no.7
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• pp.579-587
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• 2007

Samchunpo(Sin Hyang) Harbor is located in the bay of Sa Chun, the central south coast of Korean peninsula. The harbor and coastal boundaries have been protecting by natural coastal islands and shoals. Currently, The Sin Hyang harbor needs maintenance and renovation of the sheltered structures against the weather deterioration and typhoon damages. Consequently to support this, the calculation of accurate design wave through the typhoon wave attack is necessary. In this study, calculation of incident wave condition is simulated using steady state spectrum energy wave model(wide area wave model) from 50 years return wave condition. And this simulation results in wide offshore area were used for the input of the extended mild slope wave model at the narrow coastal area. Finally, the calculation of design wave at Sin Hyang harbor entrance was induced by Boussinesq wave model(detail area wave model) simulation. The numerical model system was able to simulate wave transformations from generation scale to shoreline or harbor impact. We hope these results will be helpful to the engineers doing placement, design, orientation, and evaluation of a wide range of potential solutions in this area.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.948-948
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• 2012

합천댐유역에 대한 기후변화에 따른 수문학적 영향을 정량적으로 분석하기 위해, 기상청에서 제공하는 공간해상도 27km의 MM5 RCM(Regional Climate Model)을 사용하였다. RCM의 기상변수들은 공간적 스케일의 상이성과 RCM 기후변수들의 불확실성 때문에 유출모형인 SWAT의 입력자료로 사용하기에는 어려움이 있다. 특히, RCM 변수들 중 강수량의 경우 한반도 지역의 6월과 10월 사이에 연강수량의 67%이상이 집중되는 계절성을 반영하지 못하고 있는 실정이기 때문에 국내 유역의 유출량 산정에 사용하기 위해서는 지역적 상세화(Downscaling)가 필요하다. 본 연구에서는 RCM 기후변수에 내포된 공간적 스케일의 상이성과 불확실성을 최소화하기 위해 강우관측소 지점을 단위로 한 다지점 인공신경망 기법을 적용하여 강수량, 습도, 최고기온 및 최저기온에 대한 상세화를 실시하였다. 강수의 경우 여름철 태풍사상을 모의하기 위한 Stochastic Typhoon Simulation기법과 Baseline(1991~2010)과 Projection(2011~2100) 사이의 강수량 보정을 위한 Dynamic Quantile Mapping 기법을 적용하여, 강수량의 불확실성을 최소화 하고자 하였다. 상세화된 기후자료를 이용한 SWAT 모형의 일(Daily) 단위 강우-유출 모의결과를 2011~2040년, 2041~2070년, 2071~2100년으로 구분하여 추세분석을 실시하였다.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.1-8
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• 2011

In this study, a wind hazard map over Korea peninsula based on geographical information is developed, which consists of the surface roughness model, the topographical effect model and the homogeneous wind model. The surface roughness model is assessed to evaluate the effect of the surface roughness on the wind field near ground. The topographical effect model is assessed to quantify the effect of the speed-up caused by topology, which is calculated by adopting the topographical effect factor in Korea building code (2005). The homogeneous wind map is created either by a frequency analysis method for meteorological data or a typhoon simulation. The results show that the wind hazard map can be applied to the determination of insurance premium as well as the assessment of loss and damage.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.2B
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• pp.193-205
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• 2009

Typhoons occurred in the tropical Pacific region, these might be affected the Korea moving toward north. The strong winds and the heavy rains by the typhoons caused a natural disaster in Korea. In the research, the heavy rainfall events based on typhoons were evaluated quantitative through various statistical techniques. First, probability precipitation and typhoon probability precipitation were compared using frequency analysis. Second, EST probability precipitation was calculated by Empirical Simulation Techniques (EST). Third, NL probability precipitation was estimated by coupled Nonparametric monte carlo simulation and Locally weighted polynomial regression. At the analysis results, the typhoons can be effected Gangneung and Mokpo stations more than other stations. Conversely, the typhoons can be effected Seoul and Inchen stations less than other stations. Also, EST and NL probability precipitation were estimated by the long-term simulation using observed data. Consequently, major hydrologic structures and regions where received the big typhoons impact should be review necessary. Also, EST and NL techniques can be used for climate change by the global warming. Because, these techniques used the relationship between the heavy rainfall events and the typhoons characteristics.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.465-480
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• 2020

Numerical simulations of the storm surge and the wave induced by the Typhoon Sanba incident on the south coast of Korea in 2012 are conducted 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 harbors along the coasts of Korea. For the waves the calculated significant wave heights are compared with the data measured using the wave buoys and the underwater pressure type wave gauge. As a result the JMA-MSM and the NCEP-CFSR weather fields give the highest reliability. The ECMWF-ERA5 gives in general surge and wave heights weaker than the measured. The ECMWF-ERA5, however, reproduces the best convergence belt formed in front of the typhoon. The weather field obtained using JTWC best track information gives the worst agreement.