• 해양환경안전학회지
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• 제4권1호
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• pp.31-40
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• 1998

Through the combination of existing tidal prediction model and numerical tidal model, the efficient tidal prediction system was formulated and applied to the neighboring area of Pusan port. Because all tidal constituents for tidal prediction (69 tidal constituents are normally used) couldn't be considered due to the physical limits on computing process, some errors between the observed and predicted values were inevitably occurred. But it was confirmed that the computed values with maximum 10% of relative errors can be obtained if four major tidal constituents(M2, S2, K1, O1) are used. Thus, if other constituents than four major tidal constituents are additionally used, more accurate values will be obtained. Furthermore, if the database for harmonic constants in coastal waters is made in advance, using the numerical tidal model, prompt tidal prediction can be achieved at any time when it is required.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1997년도 Proceedings of KIN-CIN Joint Symposium 97 on Safety of Shipping and History of Maritime Communication between Korea and China around 9th Century
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• pp.111-124
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• 1997

With the combination of existing tidal predictio model and numerical tidal model, the efficient tidal prediction system was formulated and applied to the neighboring area of Pusan port. Because all tidal constituents for prediction (normally 69 constituents are used) can't be considered due to difficulties on computing efforts, some errors between the observed and predicted values were inevitably occurred. But it was confirmed that the practical results with about 10% of relative errors were obtained if four major tidal constituents(M$_2$, S$_2$. $K_1$, $O_1$) are used at least. Thus, if other constituents than four major tidal constituents are additornaly used, more accurate results will be obtained . Furthermore, if the databases of harmonic constants in coastal waters is made in advance using the numberical tidal model, prompt tidal prediction could be achieved whenever required.

• Ocean and Polar Research
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• 제33권3호
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• pp.309-319
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• 2011

This is a preliminary study of the feasibility of obtaining reliable tidal current harmonic constants, using one month of current observations, to verify the accuracy of a tidal model. An inference method is commonly used to separate out the tidal harmonic constituents when the available data spans less than a synodic period. In contrast to tidal constituents, studies of the separation of tidal-current harmonics are rare, basically due to a dearth of the long-term observation data needed for such experiments. We conducted concurrent and monthly harmonic analyses for tidal current velocities and heights, using 2 years (2006 and 2007) of current and sea-level records obtained from the Tidal Current Signal Station located in the narrow waterway in front of Incheon Lock, Korea. Firstly, the l-year harmonic analyses showed that, with the exception of $M_2$ and $S_2$ semidiurnal constituents, the major constituents were different for the tidal currents and heights. $K_1$, for instance, was found to be the 4th major tidal constituent but not an important tidal current constituent. Secondly, we examined monthly variation in the amplitudes and phase-lags of the $S_2$ and $K_1$ current-velocity and tide constituents over a 23-month period. The resultant patterns of variation in the amplitudes and phase-lags of the $S_2$ tidal currents and tides were similar, exhibiting a sine curve form with a 6-month period. Similarly, variation in the $K_1$ tidal constant and tidal current-velocity phase lags showed a sine curve pattern with a 6-month period. However, that of the $K_1$ tidal current-velocity amplitude showed a somewhat irregular sine curve pattern. Lastly, we investigated and tested the inference methods available for separating the $K_2$ and $S_2$ current-velocity constituents via monthly harmonic analysis. We compared the effects of reduction in monthly variability in tidal harmonic constants of the $S_2$ current-velocity constituent using three different inference methods and that of Schureman (1976). Specifically, to separate out the two constituents ($S_2$ and $K_2$), we used three different inference parameter (i.e. amplitude ratio and phase-lag diggerence) values derived from the 1-year harmonic analyses of current-velocities and tidal heights at (near) the short-term observation station and from tidal potential (TP), together with Schureman's (1976) inference (SI). Results from these four different methods reveal that TP and SI are satisfactorily applicable where results of long-term harmonic analysis are not available. We also discussed how to further reduce the monthly variability in $S_2$ tidal current-velocity constants.

• 한국해안·해양공학회논문집
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• 제34권6호
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• pp.222-232
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• 2022

우리나라 연안의 30개 조위관측소에서 관측된 조위자료를 조화분해하여 2021년에 대한 해역별 장주기 조석성분의 특성 및 장주기 조석성분이 총 수위 예측에 미치는 영향에 대해 알아보았다. 먼저 관측조위의 조화분해 결과, 우리나라 연안에서 장주기 조석성분은 연주조(Sa)와 반년주조(Ssa)가 우세하였으며, 해역별로는 서해안에서 약 17.8 cm의 상대적으로 큰 진폭을 보였다. 계속해서 총 수위 예측에 대한 영향을 살펴보고자, 2021년을 연구 기간으로 장주기 조석성분이 포함된 예측조위와 포함되지 않은 예측조위를 생산하였고, 각각의 예측조위를 폭풍해일 모델의 해일고 예측결과에 더하여 총 수위를 생산하였다. 장주기 조석성분을 고려하지 않은 총 수위와 고려한 총 수위의 오차를 비교한 결과, 전반적으로 뚜렷한 계절적 차이가 나타났다. 장주기 조석성분을 고려하지 않은 총 수위에 비해서, 장주기 성분이 고려된 총 수위는 여름철에는 오차가 큰 폭으로 감소하였고, 겨울철에는 강한 음의 편차를 보이며 오차가 증가하는 경향이 나타났다. 이는 우리나라 겨울철의 강한 고기압과 같은 기상현상에 의한 영향이 예측조위와 해일고 예측결과에 이중으로 반영되어 나타난 결과로 해석되었다. 해일고 예측결과를 조화분해하였을 때, 연주기 성분이 우세하였고 이를 장주기 조석성분이 고려된 총 수위에서 제거하였을 때, 특히 겨울철에 나타난 강한 음의 편차가 사라지고 연평균 RMSE도 감소하는 것으로 나타났다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1053-1057
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• 2005

The occurrence probability (OP) distributions of tide levels using harmonic constants of six tidal gauging stations in Korean coastal zone were estimated and analysed in detail. OP analysis using harmonic constants data of Incheon(Youldo), Mokpo, Yeosu, Pusan, Pohang and Sokcho was carried out and compared with the OP using hourly tidal elevation data which were served through the Internet Homepage by the National Ocean Research Institute. The tidal elevation data were divided by the AHHW (ALLW) value referenced to MSL in order to compare the OP patterns in a relative scale. The OP of the tidal elevation calculated using 38 harmonic tidal constituents relatively well agreed with those of hourly observed tidal elevation data. However, the OP results using four harmonic tidal constituents overestimate the occurrence probability at the peak points and underestimate at the tail-regions of the OP. Especially, the OP patterns of the Sokcho and Pohang tidal gauging stations on the East Sea show totally different patterns and the estimation method using four harmonic constants should be modified and application should be strictly limited on the East Sea areas. The OP patterns are considerably well generated in case of the OP generation using the additional two or three dominant tidal constituents,

• 한국측량학회지
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• 제36권5호
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• pp.343-353
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• 2018

Ocean tides in Antarctica are not well constrained mostly due to the lack of tidal observations. Especially, tides underneath and around ice shelves are uncertain. InSAR (Interferometric Synthetic Aperture Radar) data has been used to observe ice shelf movements primarily caused by ocean tides. Here, we demonstrate that it is possible to estimate tidal constituents underneath the Sulzberger ice shelf, West Antarctica, solely using ERS-1/2 tandem mission DInSAR (differential InSAR) observations. In addition, the tidal constituents can be estimated in a high-resolution (~200 m) grid which is beyond any tidal model resolution. We assume that InSAR observed ocean tidal heights can be derived after correcting the InSAR data for the effect of atmospheric loading using the inverse barometric effect, solid earth tides, and ocean tide loading. The ERS (European Remote Sensing) tandem orbit configuration of a 1-day separation between SAR data takes diminishes the sensitivity to major tidal constituents including $K_1$ and $S_2$. Here, the dominant tidal constituent $O_1$ is estimated using 8 differential interferograms underneath the Sulzberger ice shelf. The resulting tidal constituent is compared with a contemporary regional tide model (CATS2008a) and a global tide model (TPXO7.1). The InSAR estimated tidal amplitude agrees well with both models with RMS (root-mean-square) differences of < 2.2 cm and the phase estimate corroborating both tide models to within $8^{\circ}$. We conclude that fine spatial scale (~200 m) Antarctic ice shelf ocean tide determination is feasible for dominant constituents using C-band ERS-1/2 tandem mission InSAR.

• 한국해양환경ㆍ에너지학회지
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• 제13권4호
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• pp.234-240
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• 2010

연안개발로 인해 발생하는 해양환경 변화를 정확히 예측하여 해양환경을 효율적으로 관리하기 위해서는 정확한 조위 및 조류 분포에 관한 자료의 확보가 필수적이다. 그러나 현재 대부분의 환경영향평가에서는 조석 수치모의에서 제한된 조석분조 만을 사용하여 조위와 조류분포를 예측하여 많은 분조의 합성에 의해 발생되는 실제 조석현상을 정확하게 계산하지 못하고 있으며, 이로 인해 환경영향평가에 오류가 발생하고 있다. 본 연구에서는 제한된 분조의외해 개방경계에서 조화상수를 가지고도 연안에서 관측된 조위자료를 활용하여 실시간으로 정확하게 조위 및 조류 분포를 예측할 수 있는 방법을 제안하였다. 4개 분조에 의한 조위와 38개 분조에 의한 조차의 비 그리고 모의조차와 관측조차의 비를 가지고 보정한 조위 예측결과는 관측조위와 잘 일치하였다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.219-220
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• 2006

In Korea, Yellow sea which is located west side of korea has a between 2.8 to 8.0 m tidal range. So, Vessel Traffic Support System(VTSS) is designed to provide predicted water level, tidal elevation and tide induced current. VTSS has a 58 tidal constituents from 1 year tide observed data and 23 tidal current constituents from 1 month current data at Dang-Jin P.P harbor. Predicted data visualized with graphs, vectors and stick plot. The purpose of VTSS give to information to maritime pilot for help to make decision schedule.

• 한국환경과학회지
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• 제23권4호
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• pp.661-672
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• 2014

Due to tidal force, it is very difficult to estimate the hydraulic parameters of high permeable aquifer near coastal area in Jeju Island. Therefore, to eliminate the impact of tidal force from groundwater level and estimate the hydraulic properties, tidal response technique has been mainly studied. In this study we have extracted 38 tidal constituents from groundwater level and harmonic constants including frequency, amplitude, and phase of each constituent using T_TIDE subroutine which is used to estimate oceanic tidal constituents, and then we have estimated hydraulic diffusivity associated with amplitude attenuation factor(that is the ratio of groundwater level amplitude to sea level amplitude for each tidal constituent) and phase lag(that is phase difference between groundwater level and sea level for each constituent). Also using harmonic constants for each constituent, we made the sinusoidal wave and then we constructed the synthesized wave which linearly combined sinusoidal wave. Finally, we could get residuals(net groundwater level) which was excluded most of tidal influences by eliminating synthesized wave from raw groundwater level. As a result of comparing statistics for synthesized level and net groundwater level, we found that the statistics for net groundwater level was more insignificant than those of synthesized wave. Moreover, in case of coastal aquifer which the impact of tidal force is even more than those of other environmental factors such as rainfall and groundwater yield, it is possible to predict groundwater level using synthesized wave and regression analysis of residuals.

• 한국해안해양공학회지
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• 제3권1호
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• pp.29-37
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• 1991

동해남부해역에서 주요 4개 분조($M_2,;S_2,;K_1,;O_1$)의 조석운동을 유한요소법을 이용한 2차원조석수치모형을 수립하여 계산하였다. 계산결과는 조석관측치와 비교되었으며, 기존의 조석도들과도 비교 분석되었다. 계산된 조석은 관측된 조석과 비교적 일치하였으며, 계산결과로부터 주요 4개 분조의 상세한 조석도가 작성되었다. 또한,$M_2$분조와 $K_1$분조의 조류타원분포가 제시되었다. 작성된 조석도에 의하면 무조점의 위치는 반일주조의 경우 기존의 조석도와 일치하나, 일주조의 경우는 한국연안에 더 치우쳐 나타났다.