• 한국해양학회지
• /
• v.22 no.1
• /
• pp.9-18
• /
• 1987

A number of hydrographic studies and some recent current measurements around Chejudo Island suggest an existence of a clockwise residual flow in the west and north coasts of the island all the year round. On the eastern side of the island the Tsushinma Current flows northward and northeastward. The contribution of tide-induced residual currents to the observed residual. flow around the island was examined here through numerical solution of the two-dimensional nonlinear shallow-water equations. The calculated tide-induced residual currents show a clockwise circulation around the island. Significant residuals of 2-4cms$\^$-1/are confined over sloping bottom topography around t he island and the far-field residuals are negligibly small. The inclusion of a permanent current into the model was also attempted in order to see the effects of the Tsushima Current system on the residual circulation around the is land. It was found that combined effects of tide-induced residuals and the permanent current field associatedwith the Tsushima Current explain qualitatively not only the observed clock wise residuals in the west and north coasts but also the northward flow on the eastern side of the island.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.6
• /
• pp.594-599
• /
• 2001

In a sandy shore surf zone of Dolsan Island, diel, tidal and seasonal effects on abundance of Acartia omorii were investigated at three sites, the bottom and surface of 1 m depth and water's edge using a sledge-net. Of these sites, the abundance of A. omorii was the highest in the bottom. Seasonal abundance data showed that A. omorii was more abundant in winter than other seasons. During the study period, the abundance of A. omorii was always higher during ebb tide than flood, The distribution patterns of A. omorii were more influenced by tide than diel change, Strong current during spring tide possiblely affected the diel migration pattern, In winter A. omorii showed a diel vortical migration in neap tide, whereas it showed a reverse vortical diel migration in spring tide. Distribution centers were located at a layer of $50\~100\;cm$ below mean sea level (MSL) during neap tide, and then it moved slightly upward during spring tide.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.21 no.4
• /
• pp.317-322
• /
• 2003

This paper have calculated a relative heights of an each station using the data which were observed by GPS permanent stations(Chejudo, Homigoj, Jumunjin, Marado, Palmido, Ulengdo, Youndo) established in Korea. We performed spectrum analysis with a calculated relative heights by CLEAN algorithm. Through these process, we estimated vertical displacement of earth surface by semi-dinural ocean tidal loading components, and compared them with the results which were calculated by improving ocean tide model(NA099jb) for adjacent seas around Japan and Korea. As the result of this study, we determined the ocean tidal loading components with loading effects of $M_2$ and $N_2$, and we noted that the amplitude and the phase lags of ocean tidal loading components from observed GPS data were almost equal to values calculated from ocean tide models. However, the loading components about semi-diurnal tide $S_2$, $K_2$ couldn't estimate because of periods. Also, the diurnal ocean tide loading components were not considered, because the noise level have increased during the diurnal frequency.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.8 no.2
• /
• pp.137-145
• /
• 1996

Effects of nonlinear terms on the generation of M$_2$ tide residual elevation and M$_4$ tide in the Yellow Sea and the East China Sea are investigated using a depth-integrated two-dimensional nonlinear M$_2$tidal model. The model domain (117$^{\circ}$E-130$^{\circ}$E, 24$^{\circ}$N-41$^{\circ}$N) covers the whole region of the Yellow Sea and the East China Sea with grid resolution of 1/6$^{\circ}$ in longitude and 1/8$^{\circ}$in latitude. A radiational boundary condition is used along the open boundaries. Calculations show that advection terms yield negative residual elevation, while shallow-water terms in continuity equation yield positive residual elevation. The contribution of both advection terms and shallow-water terms to tile generation of the M$_4$ constituent is more than 90 percents, but that of quadratic bottom friction terms to the M$_4$ constituent is comparatively small.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.1B
• /
• pp.99-106
• /
• 2006

Due to both global warming and constructions of seadike/seawalls, continuously or abruptly rising tendencies of extreme high water levels have been detected at Kunsan and Mokpo harbors. This paper deals firstly with the separation of each effect, namely global warming effect and construction effect, on increases of water level quantitatively by a linear regression method. And then, it can be explained why and how the extreme high water levels had been risen just after constructions at both harbors. A numerical simulation of $M_2$ tidal constituent at Mokpo coastal zone shows that the tidal amplification by constructions is mainly due to the extinguishment of TCE at Mokpogu. The tidal flat effect makes the amplification more deepen at spring tide or extreme high tide, which results in the increase of inundation risk at Mokpo harbor. A frequency analysis method is applied, which is shown to be effective at such a site of having non-homogeneous tidal data due to constructions as Mokpo harbor.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
• /
• 2002.08a
• /
• pp.177-183
• /
• 2002

우리나라의 서해안은 많은 도서가 산재해 있고 지형이 복잡하며 조석의 간만의 차가 크게 나타나 연안을 따른 조간대가 폭넓게 형성되어 있다. 연안해역에 대해 새만금과 시화호 같은 부영양화 환경문제나 군산지구 개발사업 같은 연안공사에 따른 퇴적물 이동 등 다양한 연구가 진행되고 있다. (중략)

• Proceedings of the SAREK Conference
• /
• 2007.06a
• /
• pp.102-102
• /
• 2007

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.13 no.2
• /
• pp.100-108
• /
• 2001

Along the shoreline a special treatment is required to simulate movement of periodic waves such as tsunami and tide because of continuous movement of shoreline as waves rise and recede. A moving boundary treatment is first proposed to track the movement of shoreline in this study. The treatment is then employed to obtain a maximum inundation area to be used for mitigation of coastal flooding. The obtained maximum inundation zone for a specific location is compared to that of available observed data. A reasonable agreement is observed.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2004.05b
• /
• pp.1007-1011
• /
• 2004

영산강하구언과 영암 및 금호방조제 건설에 의해 목포해역에서는 조석확폭현상이 발생하여 만조위가 상승함에 따라 저지대에 침수피해를 야기시킨 바 있다. 이는 목포구의 'tidal choking effect' 기능이 상실됨에 기인한다는 결론을 선행인구(강주환, 1996)에서 얻은 바 있다. 본 인구에서는 선행연구에 비해 전체 영역이 확대되었으며 격자크기가 작아졌을 뿐 아니라 관심영역에는 세부역을 도입하여 더욱 세밀한 격자체계를 구성하였다. 이에 따라 조간대 처리가 한층 정밀해졌으며, 천해조 경계조건 부여와 함계 낙조우세를 실제에 가깝게 재현시킬 수 있게 되었다. 또한 방조제 건설후 낙조우세가 심화되는 자정을 모의할 수 있게 됨에 따라 소류사 이동양상의 변화된 패턴 역시 파악할 수 있었으며, 만조위 상승에 따른 침식유발 효과와 더불어 인근 해역의 침식 원인을 부분적으로 규명할 수 있었다.

• Korean Journal of Remote Sensing
• /
• v.39 no.5_1
• /
• pp.467-479
• /
• 2023

Satellite altimeters have continuously observed sea surface height (SSH) in the global ocean for the past 30 years, providing clear evidence of the rise in global mean sea level based on observational data. Accurate altimeter-observed SSH is essential to study the spatial and temporal variability of SSH in regional seas. In this study, we used measurements from the Ieodo Ocean Research Station (IORS) and validate SSHs observed by satellite altimeters (Envisat, Jason-1, Jason-2, SARAL, Jason-3, and Sentinel-3A/B). Bias and root mean square error of SSH for each satellite ranged from 1.58 to 4.69 cm and 6.33 to 9.67 cm, respectively. As the matchup distance between satellite ground tracks and the IORS increased, the error of satellite SSHs significantly amplified. In order to validate the correction of the tide and atmospheric effect of the satellite data, the tide was estimated using harmonic analysis, and inverse barometer effect was calculated using atmospheric pressure data at the IORS. To achieve accurate tidal corrections for satellite SSH data in the seas around the Korean Peninsula, it was confirmed that improving the accuracy of tide data used in satellites is necessary.