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Analysis of Tidal Asymmetry and Flood/Ebb Dominance around the Yeomha Channel in the Han River Estuary

한강하구 염하수로 주변에서의 조석·조류 비대칭과 창·낙조 우세 분석

  • Received : 2012.05.25
  • Accepted : 2012.06.18
  • Published : 2012.09.30

Abstract

Han River estuary (HRE) is located at the middle of the western coast of Korea, and tidal currents were measured at 4 stations in this estuary during the winter season, and previously observed tide data was analyzed. The results of amplitude ratio of $M_4/M_2$ showed that increasing upward to estuary in the HRE. Tide harmonic constants of relative phase $2M_2-M_4$ represent flood dominance, with under 180 degree. But this method has a limit of analysis that typically based on the non-linear distortion of the tidal current in tidal lagoon system where freshwater discharge is assumed to be relatively small. The results of statistically tidal current data indicated that ebb current velocity would be great unlike tide data. Ebb and flood duration time is calculated by slack time of tidal current showed that ebb duration time is longer than flood. The results of correlation of analysis show high value (0.9) between tidal current stations from Incheon harbor to north entrance of Yeomha channel. We reconstructed to find the reasons for the features of ebb dominance the results of harmonic analysis. As major component ($M_2$) in combination with shallow water component ($M_4$), the tidal curve was presented flood dominance that has a flood current is stronger. However, these curve were changed to ebb dominance add up the non-harmonic components that had ebb direction flow by calculated tidally averaged current. The characteristic of enhancement on ebb is showed around the Yeomha channel in the HRE, because averaged flow which acts seaward such as long-term tidal current components due to non-linear effect and freshwater which overcome the flood current.

한강하구 염하수로 주변의 조석 조류 변형과 창 낙조 우세를 분석하기 위해서 4개 정점에서 동기간에 관측한 조류자료와 기 관측된 조석자료를 분석하였다. 조석 및 조류의 변형 정도는 $M_4/M_2$ 진폭비를 분석한 결과 상류로 갈수록 증가하며, 조석의 상대 위상차($2M_2-M_4$)를 계산하면 모든 정점의 값이 $180^{\circ}C$ 이하로 창조 우세를 보여준다. 그러나 조류자료의 통계분석 결과를 보면 조석 조화상수의 상대 위상차 결과와는 다르게 최강 평균 낙조가 창조에 비하여 강하게 나타나며, 정조시각을 이용하여 창조, 낙조 지속시간을 계산하면 낙조 지속시간이 길게 나타난다. 각 조류 관측정점의 주축 방향 유속성분의 상관도를 분석한 결과 인천항 이후 염하수로 북쪽입구까지는 상관도 값이 0.9 이상으로 높게 나타났다. 조류 분석결과에서 보여지는 낙조가 우세하고 낙조 지속시간이 긴 형태의 원인을 분석하기 위해서 조화분해 결과를 재구성하였다. 주 분조($M_2$)와 천해 분조($M_4$)를 결합하면 창조가 우세하고 낙조 지속시간이 긴 전형적인 창조우세 형태의 곡선이 나타난다. 그러나 이 곡선에 조류 성분의 산술 합으로 계산한 비 조류성분(잔차류)의 값을 더하면 낙조가 강해지고 낙조 지속시간이 긴 형태로 나타난다. 즉, 천해분조에 의해서 발생하는 상류방향의 흐름을 극복하는 담수와 하구 비선형 효과에 의해서 생성되는 장주기 조류성분과 같은 낙조방향의 평균적인 흐름이 존재하기 때문에 독특한 낙조심화 현상이 염하수로에서 나타난다.

Keywords

References

  1. 강주환 (2000). "우리나라 서남해역의 창 낙조우세와 황해에서의 조류타원도 회전." 대한토목학회논문집, 대한토목학회, 제20권, 제II-2호, pp. 269-276.
  2. 국립해양조사원(2002). 한강 임진강 유역에 대한 조위영향 연구(II). 한국해양연구원, 한국건설기술연구원, BSPM 00080-00-1345-2.
  3. 김창식, 임학수, 김진아, 김선정, 박광순, 정경태(2010). "경기만 조석 잔차류산정 및 변동성." 한국해안.해양공학회 논문집, 한국해안해양공학회, 제22권, 제6호, pp. 353-360.
  4. 송용식, 우승범(2011). "염하수로 인근에서 조석 변형과 장주기 조류성분의 변동 특성." 한국해안.해양공학회 논문집, 한국해안해양공학회, 제23권 제5호, pp. 393-400.
  5. 윤병일, 우승범 (2011). "조석 전파 특성을 활용한 한강하구 주요 수로의 지형학적 수렴과 바닥 마찰 간의 관계에 대한 연구." 한국해안.해양공학회 논문집, 한국해안해 양공학회, 제23권 제5호, pp. 383-392.
  6. 인하대학교(2003). 창후항 박지보수 및 창후리 교동간 항로 보수를 위한 준설 관련 해양조사 보고서. 해양과학기술연구소.
  7. Aubrey, D.G., and Speer, P.E. (1985). "A Study of Nonlinear Tidal Propagation in Shallow Inlet/Estuarine Systems. Part I: Observations." Estuarine, Coastal Shelf Science, Elsevier, Vol. 21, No. 2, pp. 185-205. https://doi.org/10.1016/0272-7714(85)90096-4
  8. Aubrey, D.G. (1986). "Hydrodynamic controls on sediment transport in well-mixed bays and estuaries." Physics of Shallow Estuaries and Bays, Edited by van de Kreeke, J., Springer, Berlin, pp. 245-258.
  9. Blanton, J.O., Lin G., and Elston, S.A. (2002). "Tidal current asymmetry in shallow estuaries and tidal creeks." Continental Shelf Research, Elsevier, Vol. 22, No. 11-13, pp. 1731-1743. https://doi.org/10.1016/S0278-4343(02)00035-3
  10. Cloern, J.E. (1987). "Turbidity as a control on phytoplankton biomass and productivity in estuaries." Continental Shelf Research, Elsevier, Vol. 7, No. 11-12, pp. 1367-1381. https://doi.org/10.1016/0278-4343(87)90042-2
  11. Dronker, J. (1986). "Tidal asymmetry and estuarine morphology." Netherlands Journal of Sea Research, Elsevier, Vol. 20, No. 2, pp. 117-131. https://doi.org/10.1016/0077-7579(86)90036-0
  12. Friedrichs, C.T., and Aubrey, D.G. (1988). "Nonlinear tidal distortion in shallow well mixed estuaries: A synthesis." Estuarine, Coastal Shelf Science, Elsevier, Vol 26, No. 5, pp. 521-545.
  13. Ippen, A.T., and Harleman, D.R.F. (1966). "Tidal Dynamics in Estuaries." Estuary and Coastline Hydrodynamics, Edited by Ippen, A.T., McGraw-Hill, New York, pp. 493-545.
  14. Kang, J.W., and Jun, K.S. (2003). "Flood and ebb dominance in estuaries in Korea." Estuarine, Coastal Shelf Science, Elsevier, Vol. 56, No. 1, pp. 187-196. https://doi.org/10.1016/S0272-7714(02)00156-7
  15. Lanzoni, S., and Seminara, G. (1998). "On tide propagation in convergent estuaries." Journal of Geophysical, Research, AGU, Vol. 103, No. C13, pp. 30,793-30,812. https://doi.org/10.1029/1998JC900015
  16. Nidzieko, N.J., and Ralston, D.K. (2012). "Tidal asymmetry and velocity skew over tidal flats and shallow channels within a macrotidal river delta" Journal of Geophysical Research-Oceans, AGU, Vol. 117, C03001, doi:10.1029/2011JC007384.
  17. Park, K., Oh, J.H., Kim H.S., and Im, H.H. (2002). "Case study: Mass Transport Mechanism in Kyunggi Bay around Han River Mouth." Journal of Hydraulic Engineering, ASCE, Vol. 128, No. 3, pp. 257-267. https://doi.org/10.1061/(ASCE)0733-9429(2002)128:3(257)
  18. Preisendorfer, R.W., and Mobley, C.D. (1988). Principal Component Analysis in Meteorology and Oceanography. Elsevier Science Ltd, 425 pp.
  19. Pugh, D.T. (1987). Tides, surges and mean sea level: a handbook for engineers and scientists. Wiley, New York.
  20. Robins, P.E., and Davies, A.G. (2010). "Morphological controls in sandy estuaries: the influence of tidal flats and bathymetry on sediment transport." Ocean Dynamics, Springerlink, Vol. 60, No. 3, pp. 503-517. https://doi.org/10.1007/s10236-010-0268-4
  21. Seim, H., Blanton, J., and Elston, S. (2006). "Tidal circulation and energy dissipation in a shallow, sinuous estuary." Ocean Dynamics, Springerlink, Vol. 56, No. 3-4, pp. 360-375. https://doi.org/10.1007/s10236-006-0078-x
  22. Speer, P.E., and Aubrey, D.G. (1985). "A study of nonlinear tidal propagation in shallow inlet/estuarine systems. Part II: theory." Estuarine, Coastal Shelf Science, Elsevier, Vol. 21, No. 2, pp. 207-224. https://doi.org/10.1016/0272-7714(85)90097-6
  23. Speer, P.E., Aubrey, D.G., and Friedrichs, C.T. (1991). "Nonlinear hydrodynamics of shallow tidal inlet/bay system Estuarine." Tidal Hydrodynamics, Edited by Parker, B.B., Wiley, Chichester, pp. 321-339.
  24. Wang, Z.B., Jeuken, M.C.J.L., Gerritsen, H., De Vriend, H.J., and Kornman, B.A., (2002). "Morphology and asymmetry of the vertical tide in the Westerschelde estuary." Continental Shelf Research, Vol. 22, No. 17, pp. 2599-2609. https://doi.org/10.1016/S0278-4343(02)00134-6
  25. Woo, S.B., and Yoon, B.I. (2011). "The Classification of Estuary and Tidal Propagation Characteristics in the Gyeong-Gi Bay, South Korea." Journal of Coastal Research, CERF, Special Issue Vol. 64, pp. 1624-1628.

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