Enhanced Exchange Flow During Spring Tide and Its Cause in the Sumjin River Estuary, Korea

  • Eun-Byeol Cho
  • Yang-Ki ChoEmail author
  • Jongkyu Kim
Special Issue: Climate Change and Anthropogenic Change around Korean Peninsula


Knowledge of exchange flow and its variations is important, because it determines the distribution of salt, nutrient, pollutant, and suspended sediment in estuaries. Although exchange flow has been studied extensively, their variations over the spring–neap tidal cycle remain unclear. Many studies have indicated that the exchange flow is weaker during spring tides than neap tides, but others have reported that it might be stronger during spring tides. Therefore, we investigated the spring–neap variation of an exchange flow and its cause based on intensive observational data and an analytical model applied to the Sumjin River estuary (SRE), Korea. The observations revealed that exchange flow increased during the spring tide but decreased during the neap tide. The horizontal salinity gradient increased about seven times more during spring tide than during neap tide in the middle of the estuary. The analytical model implied that the exchange flow in the SRE is mainly driven by the horizontal salinity gradient. The large horizontal salinity gradient and tidal current amplitude ratio in the SRE between the spring and neap tides suggests that the horizontal pressure gradient driven by the salinity gradient overwhelms vertical mixing in driving exchange flow in the SRE.


Exchange flow Salinity gradient Sumjin River estuary Tide 



This research was a part of the project titled “Long-term change of structure and function in marine ecosystems of Korea,” funded by the Ministry of Oceans and Fisheries, Korea.


  1. Andutta, F.P., L.B. de Miranda, C.A. Franca Schettini, E. Siegle, M.P. da Silva, V.M. Izumi, and F.M. Chagas. 2013. Temporal variations of temperature, salinity and circulation in the Peruipe river estuary (nova Vicosa, BA). Continental Shelf Research 70: 36–45. Scholar
  2. Becker, M.L., R.A. Luettich, and H. Seim. 2009. Effects of intratidal and tidal range variability on circulation and salinity structure in the Cape Fear River Estuary, North Carolina. Journal of Geophysical Research 114 (C4).
  3. Bowen, M.M., and W. Geyer. 2003. Salt transport and the time-dependent salt balance of a partially stratified estuary. Journal of Geophysical Research-Oceans 108 (C5).
  4. Dalrymple, R.W., B.A. Zaitlin, and R. Boyd. 1992. Estuarine facies models: conceptual basis and stratigraphic implications: perspective. Journal of Sedimentary Research 62: 6.CrossRefGoogle Scholar
  5. de Miranda, L.B., A.L. Bérgamo, and B.M. de Castro. 2005. Interactions of river discharge and tidal modulation in a tropical estuary, NE Brazil. Ocean Dynamics 55 (5–6): 430–440. Scholar
  6. Defant, A. 1960. Physical oceanography; volume 2, 598. Oxford: Pergamon Press.Google Scholar
  7. Dijkstra, Y.M., H.M. Schuttelaars, and H. Burchard. 2017. Generation of exchange flows in estuaries by tidal and gravitational eddy viscosity-shear covariance (ESCO). Journal of Geophysical Research, Oceans 122 (5): 4217–4237. Scholar
  8. Fischer, H., E. List, R. Koh, J. Imberger, and N. Brooks. 1979. Mixing in estuaries. Mixing in Inland and Coastal Waters, 229–278.CrossRefGoogle Scholar
  9. Garvine, R.W. 1985. A simple model of estuarine subtidal fluctuations forced by local and remote wind stress. Journal of Geophysical Research, Oceans 90 (C6): 11945–11948.CrossRefGoogle Scholar
  10. Geyer, W.R., and P. MacCready. 2014. The Estuarine Circulation. Annual Review of Fluid Mechanics 46 (1):175-197.
  11. Geyer, W.R., J.H. Trowbridge, and M.M. Bowen. 2000. The dynamics of a partially mixed estuary. Journal of Physical Oceanography 30 (8): 2035–2048.<2035:Tdoapm>2.0.Co;2.CrossRefGoogle Scholar
  12. Gong, W.P., J.P.Y. Maa, B. Hong, and J. Shen. 2014. Salt transport during a dry season in the Modaomen Estuary, Pearl River Delta, China. Ocean and Coastal Management 100: 139–150. Scholar
  13. Hansen, D.V., and M. Rattray. 1965. Gravitational circulation in straits and estuaries. Journal of Marine Research 23: 104–122.Google Scholar
  14. Hansen, D.V., and M. Rattray. 1966. New dimensions in estuary classification. Limnology and Oceanography 11 (3): 319–326.CrossRefGoogle Scholar
  15. Huzzey, L.M., and J.M. Brubaker. 1988. The formation of longitudinal fronts in a coastal plain estuary. Journal of Geophysical Research, Oceans 93 (C2): 1329–1334.CrossRefGoogle Scholar
  16. Jay, D.A., and J.D. Smith. 1990. Circulation, density distribution and neap-spring transitions in the Colombia River Estuary. Progress in Oceanography 25 (1–4): 81–112. Scholar
  17. Kim, B.G., and Y.K. Cho. 2017. Tide-induced residual circulation in a bay with laterally asymmetric depth. Journal of Geophysical Research, Oceans 122 (5): 4040–4050. Scholar
  18. Li, C.Y., and J. O'Donnell. 1997. Tidally driven residual circulation in shallow estuaries with lateral depth variation. Journal of Geophysical Research-Oceans 102 (C13): 27915–27929. Scholar
  19. Li, M., and L.J. Zhong. 2009. Flood-ebb and spring-neap variations of mixing, stratification and circulation in Chesapeake Bay. Continental Shelf Research 29 (1): 4–14. Scholar
  20. MacCready, P., and W.R. Geyer. 2010. Advances in estuarine physics. Annual Review of Marine Science 2 (1): 35–58. Scholar
  21. Masson, D., and P.F. Cummins. 2000. Fortnightly modulation of the estuarine circulation in Juan de Fuca Strait. Journal of Marine Research 58 (3): 439–463. Scholar
  22. Officer, C. 1976. Physical oceanography of estuaries John Wiley & Sons. New York 4:65.Google Scholar
  23. Park, K., and A.Y. Kuo. 1996. Effect of variation in vertical mixing on residual circulation in narrow, weakly nonlinear estuaries. Buoyancy Effects on Coastal and Estuarine Dynamics: 301–317.Google Scholar
  24. Prandle, D. 1985. On salinity regimes and the vertical structure of residual flows in narrow tidal estuaries. Estuarine, Coastal and Shelf Science 20 (5): 615–635.CrossRefGoogle Scholar
  25. Pritchard, D.W. 1952. Salinity distribution and circulation in the Chesapeake Bay estuarine system. Journal of Marine Research 11 (2): 106–123.Google Scholar
  26. Pu, X., J.Z. Shi, G.-D. Hu, and L.-B. Xiong. 2015. Circulation and mixing along the north passage in the Changjiang River estuary, China. Journal of Marine Systems 148: 213–235. Scholar
  27. Ross, L., A. Valle-Levinson, A. Sottolichio, and N. Huybrechts. 2017. Lateral variability of subtidal flow at the mid-reaches of a macrotidal estuary. Journal of Geophysical Research-Oceans 122 (9): 7651–7673. Scholar
  28. Schettini, C.A.F., K. Ricklefs, E.C. Truccolo, and V. Golbig. 2006. Synoptic hydrography of a highly stratified estuary. Ocean Dynamics 56 (3–4): 308–319. Scholar
  29. Scully, M.E., C. Friedrichs, and J. Brubaker. 2005. Control of estuarine stratification and mixing by wind-induced straining of the estuarine density field. Estuaries 28 (3): 321–326. Scholar
  30. Shaha, D., and Y.-K. Cho. 2009. Comparison of empirical models with intensively observed data for prediction of salt intrusion in the Sumjin River estuary, Korea. Hydrology and Earth System Sciences 13 (6): 923–933. Scholar
  31. Simpson, J.H., J. Brown, J. Matthews, and G. Allen. 1990. Tidal straining, density currents, and stirring in the control of estuarine stratification. Estuaries 13 (2): 125–132. Scholar
  32. Stacey, M.T., J.R. Burau, and S.G. Monismith. 2001. Creation of residual flows in a partially stratified estuary. Journal of Geophysical Research 106 (C8): 17013. Scholar
  33. Stacey, M.T., M.L. Brennan, J.R. Burau, and S.G. Monismith. 2010. The tidally averaged momentum balance in a partially and periodically stratified estuary. Journal of Physical Oceanography 40 (11): 2418–2434. Scholar
  34. Talke, S.A., H.E. de Swart, and H.M. Schuttelaars. 2009. Feedback between residual circulations and sediment distribution in highly turbid estuaries: an analytical model. Continental Shelf Research 29 (1): 119–135. Scholar
  35. Toublanc, F., I. Brenon, T. Coulombier, and O. Le Moine. 2015. Fortnightly tidal asymmetry inversions and perspectives on sediment dynamics in a macrotidal estuary (Charente, France). Continental Shelf Research 94: 42–54. Scholar
  36. Valle-Levinson, A. 2010. Contemporary issues in estuarine physics. Cambridge University Press.Google Scholar
  37. Valle-Levinson, A. 2011. Classification of estuarine circulation. In In treatise on estuarine and coastal science, ed. E. Wolanski and D. McLusky, 75, 431–86. Academic press.Google Scholar
  38. Valle-Levinson, A., and C.A. Schettini. 2016. Fortnightly switching of residual flow drivers in a tropical semiarid estuary. Estuarine, Coastal and Shelf Science 169: 46–55. Scholar
  39. Vaz, N., P.C. Leitao, and J.M. Dias. 2007. Channel-ocean exchange driven by tides and river flow: Espinheiro Channel (Portugal). Journal of Coastal Research: 1000–1004.Google Scholar
  40. Wang, D.-P., and A. Elliott. 1978. Non-tidal variability in the Chesapeake Bay and Potomac River: evidence for non-local forcing. Journal of Physical Oceanography 8 (2): 225–232.CrossRefGoogle Scholar
  41. Wang, A.H.-J., G.J. Quigley, F.J. Kolpak, J.L. Crawford, J.H. Van Boom, G. van der Marel, and A.J.N. Rich. 1979. Molecular structure of a left-handed double helical DNA fragment at atomic resolution. Nature 282 (5740): 680–686.CrossRefGoogle Scholar
  42. Warner, J.C., W.R. Geyer, and J.A. Lerczak. 2005. Numerical modeling of an estuary: a comprehensive skill assessment. Journal of Geophysical Research-Oceans 110 (C5).
  43. Weisberg, R.H., and L. Zheng. 2003. How estuaries work: a Charlotte Harbor example. Journal of Marine Research 61 (5): 635–657. Scholar
  44. Willmott, C.J. 1981. On the validation of models. Physical Geography 2 (2): 184–194.CrossRefGoogle Scholar
  45. Wong, K.C., and J.E. Moses-Hall. 1998. On the relative importance of the remote and local wind effects to the subtidal variability in a coastal plain estuary. Journal of Geophysical Research, Oceans 103 (C9): 18393–18404.CrossRefGoogle Scholar
  46. Wong, K.-C., and A. Valle-Levinson. 2002. On the relative importance of the remote and local wind effects on the subtidal exchange at the entrance to the Chesapeake Bay. Journal of Marine Research 60 (3): 477–498.CrossRefGoogle Scholar
  47. Zhong, L., and M. Li. 2006. Tidal energy fluxes and dissipation in the Chesapeake Bay. Continental Shelf Research 26 (6): 752–770. Scholar

Copyright information

© Coastal and Estuarine Research Federation 2019

Authors and Affiliations

  1. 1.School of Earth and Environmental Sciences/Research Institute of OceanographySeoul National UniversitySeoulRepublic of Korea
  2. 2.Department of Naval Architecture and Ocean EngineeringChonnam National UniversityYeosuRepublic of Korea

Personalised recommendations