• Proceedings of the Korea Water Resources Association Conference
• /
• 2021.06a
• /
• pp.211-211
• /
• 2021

최근에 기후변화로 인한 한반도에 내습하는 태풍에 빈도는 점차 증가하고 있다. 2020년도 8월 26일 태풍 '바비', 9월 2일 태풍 '마이삭', 9월 7일 태풍 '하이선'은 일주일 내의 간격으로 한반도를 내습하였다. 한반도에 내습한 태풍 중에서 마이삭과 하이선은 동쪽 해역을 지나가면서 강풍과 많은 강우를 초래하였다. 그 결과 특정 원전은 자동 가동중지가 발생되는 사태를 야기 시켰다. 본 연구에서는 원자력 발전소 인근 해역에서 폭풍해일에 의한 가능최대파고 높이를 추정함으로써 발전소 안전성에 대한 검토에 목적을 두고 있다. 이를 위해 첫 번째로 '2019 전국 심해 설계파 산출 보고서'를 바탕으로 원전 인근 해역 심해 설계파 지점에 대해 파고, 주기, 해상풍과 같은 변수들을 분석하였다. 그 결과를 바탕으로 100년부터 1000만년까지의 변수들을 예측하였다. 두 번째로 해도자료를 바탕으로 GIS를 통한 지형자료를 구축하였다. 구축된 지형자료를 바탕으로 SWAN 모델의 기초자료를 구성하였다. 세 번째로 추정된 변수들과 구축된 지형자료를 바탕으로 100년부터 1000만년까지의 시나리오별 SWAN 시뮬레이션을 통해서 원전 인근 해역에 대한 가능 최대 파고 높이를 분석하였다. 그 결과를 바탕으로 특정 원전인근 해역에서의 평균적인 파고 높이에 대한 재해도 곡선을 추정하고 제시하였다. 본 연구를 바탕으로 향후 확률론적인 분석 방법을 적용하여 불확실성을 고려한 재해도 곡선 추정 과정의 기초자료로 활용될 수 있다. 또한 EurOtop을 적용하여 파고 높이에 따른 원전부지의 Overtopping을 추정하고, 최종적으로 폭풍해일에 의한 원전부지의 2차원 침수해석의 기초자료로 활용할 수 있을 것으로 판단된다. 이를 통해 홍수 방지 및 예방과 관련한 홍수저감 활동과 관련된 통제실 외부 시설물에 대한 수동 조작에 대한 안전성 평가가 이루어질 수 있겠다.

• Journal of the Korean earth science society
• /
• v.25 no.4
• /
• pp.277-288
• /
• 2004

In this study, state of sea surface were analyzed comparatively for cases of low atmospheric pressure, which occurred in the middle area of China and moved eastward to the Korean Peninsula across the Yellow sea during April 9-12, 1999, and typhoons 'NEIL' May 1999 and 'OLGA' July 1999, which moved northward along the west coast of the Korean Peninsula. In cases of low pressure, wind speeds and phases were respectively stronger and faster in the center area than in the surrounding areas. The wave heights seem to a somewhat differing tendency from that of the wind speeds due to the influences of geometry. On the other hand, wave heights were lower under typhoon weather than under low pressures, except the instance of wave height over 5 m on Chilbal when typhoon Olga pass northward from the southern area. Storm surges also showed larger amplitudes under low pressures than under typhoons. The results suggest that wave sand storm surges may be larger for a slow passing synoptic low pressures than for a fast passing local typhoon.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.26 no.2
• /
• pp.65-71
• /
• 2014

In recent years, strong typhoons have passed South Korea almost every year and severe damages were incurred directly and indirectly. However, instances where wave and wind data were procured from the offshore approach path of the typhoon are very rare and thus researchers are experiencing difficulties in obtaining calibration and verification data of typhoon-generated wave modeling. This paper provides a synthesis of records of observations by the Korea Meteorological Administration and Korea Institute of Ocean Science and Technology on storm waves generated by the typhoons SONGDA, NABI, and SHANSHAN that passed from 2004 to 2006 in order to help researchers interested in typhoon-generated wave numerical modeling. Although the trajectories of typhoon NABI and SHANSHAN were east of the Korea Strait, a significant wave height of 8.3 m was measured at Namhyeongjedo located east of Geojedo. Moreover, an unprecedented significant wave height of 12.2 m was measured for both typhoons at a station 1.4 km away from Yeongil Bay breakwater. Meanwhile, a comparative analysis of data obtained with a ocean data buoy at Geojedo and a Directional Waverider at Namhyeongjedo showed maximum wave heights that were similar but considerably different significant wave heights.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.23 no.4
• /
• pp.265-275
• /
• 2011

Estimation of wave height is the most important factor in the design of coastal structures such as breakwaters. In the present study, typhoon wind distribution was constructed by applying the parametric model of Holland (1980), and numerical simulations on the typhoon-generated waves were carried out using the WAM. The typhoons which affected the southern coast of the Korean Peninsula and several hypothetical typhoons were selected to construct the training sets. Design wave heights were estimated using the empirical simulation technique for various return periods and wave directions. The estimated design wave heights were compared with those by the peaks-over-threshold method and the results of KORDI(2005).

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.32 no.1
• /
• pp.26-38
• /
• 2020

A statistical test was carried out on the IID (Independently and Identically Distributed) assumption of the AM (Annual Maxima) data used to estimate the design wave height. The test was divided into independence (randomness) test and homogeneity test, and each test was conducted on AM data of 210 and 310 stations in coastal and inner coastal grids in typhoon and non-typhoon (monsoon) conditions. As a result of the independence test, the rejection ratios of the test are in the range of 1.8~5.3% and 1.4~6.0% for the non-typhoon and typhoon data sets, respectively. On the other hand, in the distribution difference test of typhoon data and nontyphoon data, the same distribution hypothesis was found to be rejected in the range of 47~79% according to the test method for both coastal grid and inner coastal grid. Therefore, in estimating design wave height by extreme value analysis, the estimation process by dividing the typhoon and non-typhoon data is appropriate.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.7 no.1
• /
• pp.47-55
• /
• 2004

In this paper, The statistical properties of ocean waves in the sea area of Hong-do, Korea are examined based on 1998-2002's wave data from a directional wave buoy. Wave data aquisition rate, mean wave heights, frequency of wave direction are summarized. Wave height and period scatter diagrams and n-year return period wave heights are estimated. Wave periods of maximum wave heights are also estimated. Large amplitude wave characteristics during the typhoon Prapiroon in 2000, Rusa in 2002 are also examined.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.35 no.4
• /
• pp.84-94
• /
• 2023

The wave height and period regression curve is widely used to estimate the design wave period. In this study, the parameters of the curves are estimated, compared, and evaluated using the linear, robust linear, and nonlinear regression methods, respectively. The data used in the design wave height estimation are the annual maxima (AM) wave height and period data sets divided by typhoon and non-typhoon conditions, provided by the Ministry of Oceans and Fisheries (2019). The estimation parameters show significant differences in the local coastal waters and the estimation methods. The estimation parameters based on the Suh et al. (2008, 2010) method show the apparent bias, under-estimation in the intercept (scale) parameter, and over-estimation in the slope (exponent) parameter, respectively.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.421-421
• /
• 2017

In order to secure the safety of coastal areas from the continuous storm surge in Korea, it is important to predict the wave movement and properties accurately during the storm event. To improve the accuracy of the storm simulation, and to quantify coastal risks from the storm event, the dependencies between wave height, wave period, and storm duration should be analyzed. In this study, therefore, copulas were used to develop multivariate statistical models of sea storms. A case study of the east coast of Korea was conducted, and the dependencies between wave height, wave period, water level, storm duration and storm interarrival time were investigated using Kendall's tau correlation coefficient. As a result of the study, only wave height, wave period, and storm duration appeared to be correlated.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.33 no.3
• /
• pp.101-109
• /
• 2021

Wave observations using a marine X-band radar are conducted by analyzing the backscattered radar signal from sea surfaces. Wave parameters are extracted using Modulation Transfer Function obtained from 3D wave number and frequency spectra which are calculated by 3D FFT of time series of sea surface images (42 images per minute). The accuracy of estimation of the significant wave height is, therefore, critically dependent on the quality of radar images. Wave observations during Typhoon Maysak and Haishen in the summer of 2020 show large errors in the estimation of the significant wave heights. It is because of the deteriorated radar images due to raindrops falling on the sea surface. This paper presents the algorithm developed to increase the accuracy of wave heights estimation from radar images by adopting convolution neural network(CNN) which automatically classify radar images into rain and non-rain cases. Then, an algorithm for deriving the Hs is proposed by creating different ANN models and selectively applying them according to the rain or non-rain cases. The developed algorithm applied to heavy rain cases during typhoons and showed critically improved results.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2006.11a
• /
• pp.477-480
• /
• 2006

본 논문에서는 한국 동해 강구항 전면해역에서 계절풍이 탁월한 3월과 태풍 우쿵(WUKONG) 내습시 8월에 수압식 파고계를 이용하여 파랑관측을 실시하였다. 관측파랑자료의 해석을 통해 관측시점에서의 계절풍 및 대풍내습시의 기상현황과 파랑과의 상호관련성, 발생파랑의 통계적 특성을 분석하였다. 그 결과에 따르면 관측기간동안 강구항 전면해역에서는 직립방파제 설계식의 관계식 $H_{max}\;=\;1.8H_S$를 초과하는 고파랑이 태풍 내습시 발생하며, 계절풍이 발달한 시기에는 약 3m 파고의 파랑이 발생하였다.