Hydrodynamic simulation experiment of tidal pump in strait waters

BACKGROUND AND OBJECTIVES: Tidal phenomena, characterized by the rise and fall of sea surface levels, play a critical role in marine dynamics, including the formation of upwelling and downwelling currents. These currents significantly influence nutrient distribution and material exchange in coastal waters. The objective of this study is to analyze the vertical current movements generated by tidal pumping in the Bangka Strait, with a particular focus on their association with tidal asymmetry and changes in the underwater topography. METHODS: A numerical simulation approach was employed using the Mike 3 Flexible Mesh software to model the hydrodynamics of the Bangka Strait. The input data included tidal measurements from the Geospatial Information Agency and bathymetric data from the Indonesian Navy Hydro-Oceanography Center. Over a duration of nine days, the simulation examined tidal patterns and their role in influencing vertical currents. Statistical methods were employed to validate the model, demonstrating a significant correlation and negligible errors when comparing simulation results and field data. FINDINGS: The study revealed that during high tide, upward currents (upwelling) were observed with speeds ranging from 0.0005 to 0.0016 meters per second, while during low tide, downward currents (downwelling) occurred with speeds 0.0002 to 0.0035 meters per second. Significant alterations in vertical current direction were observed due to bathymetric changes, particularly within the depth range of 2 to 6 meters. There was a clear indication of tidal asymmetry, with the northern Bangka Strait exhibiting a tidal range of 3.8 meters, while the southern region recorded a range of 2 meters. These variations influenced vertical current speeds and nutrient distribution patterns. This study demonstrated that the K₁ amplitude exhibited the most pronounced increase during a supermoon event, pointing to a likely strong correlation. CONCLUSION: The findings demonstrate the significant role of tidal pumping in shaping the hydrodynamics of the Bangka Strait, with implications for nutrient mixing and material transport. The outcomes yield significant information that can aid in the stewardship of coastal resources and the advancement of sustainable infrastructure in marine ecosystems. This study underscores the importance of numerical modeling in understanding complex marine dynamics and highlights the need for continued research to address the ecological and environmental impacts of tidal-induced currents. © 2025 The author(s).