The Regional Classification of Tidal Regime using Characteristics of Astronomical Tides, Overtides and Compound Tides in the Han River Estuary, Gyeonggi Bay

Abstract

In this study, we investigate tidal wave propagation characteristics, and classify regional tidal regime using tidal form number considered distribution of astronomical tide, overtides, and compound tides in the Han River Estuary, Gyeonggi Bay. The characteristics of the tidal wave propagation in main channels show dominance of major tidal constituents (e.g., and) contributing to the astronomical tide however, distinct increasing of shallow water (e.g., M 4) and long period (e.g., MS f) components toward up-estuary. Using the characteristics of tidal form number to astronomical tide, overtides, and compound tides, the regional tidal regime could be assorted into three regions. Firstly, a dominance area of astronomical tide was presented from open sea to a front of Incheon Harbor (Yeomha channel) and to north entrance of Seokmo channel. The area between south and north entrance of Yeomha channel and Ganghaw north channel classified into zone of showing strong shallow water components. It could be separated into upper estuary, upstream the Singok underwater dam, showed dominance of shallow overtides (e.g., M 4 and MS 4) water and long-term compound tides (e.g., MS f) larger magnitude than astronomical tide. The shallow water components was earlier generated in lower part (south entrance) of Yeomha channel have strong bottom by effect of shallower and narrower compared with Seokmo channel. Tidal asymmetries of upper estuary cause by a development of overtides and compound tides are mainly controlled by influence of man-made structure.

Mechanisms of Advective and Tidal Oscillatory Salt Transport in the Hypertidal Estuary: Yeomha Channel in Gyeonggi Bay

“…The current speed in the YC reaches about 1.6 m/s during the spring tide [22]. In addition, the tidal constituents associated with the nonlinear effect, such as M4 and MS4, are known to be factors that complicate the YC's tidal current pattern [16,17]. In addition to this nonlinear effect of the tide, the river flow and bottom friction cause a local flood or ebb dominance.…”

“…The current speed in the YC reaches about 1.6 m/s during the spring tide [22]. In addition, the tidal constituents associated with the nonlinear effect, such as M 4 and MS 4 , are known to be factors that complicate the YC's tidal current pattern [16,17].…”

“…The model results reproduced the tidal variations well, including the spring-neap cycle, diurnal inequality, and fortnightly inequality. Yoon et al [17] suggested that the tidal asymmetry near upstream in the YC deforms the tide level. The model also reproduced the tidal deformation at T1 proposed by Yoon et al [17].…”

“…Yoon et al [17] suggested that the tidal asymmetry near upstream in the YC deforms the tide level. The model also reproduced the tidal deformation at T1 proposed by Yoon et al [17]. We obtained harmonic constants for the model and data at eight tide stations through harmonic analysis using the T-Tide of the Matlab program.…”

“…The hypertidal estuary is generally a relatively well-mixed estuary due to strong tidal forces than river discharge. In addition, the strong tidal forces have the potential to dominate over other external forces, so the nonlinear effect of the tide is significantly increased [13][14][15][16][17]. For example, the MS f tidal constituent, referred to as the fortnightly tide formed by the interaction between M 2 and S 2 tidal constituents, significantly influences sea-level variation in the tide-dominated estuary [13].…”