Modeling investigations of tidal flat reclamation's far-field impact on tidal dynamics in the East China seas

As a result of substantial economic development in the coastal regions, the reclamation of tidal flat carried out by authorities surrounding the Bohai Sea, Yellow Sea, and East China Sea (BYECS) has reached unprecedented heights in recent decades. We are worried that tidal flat restoration will have far-reaching impacts on tidal dynamics throughout the whole BYECS. When tidal flats surrounding the BYECS are eliminated, the tidal range and phase are altered, and the amphidromic points are relocated, a numerical analysis reveals various tidal patterns owing to tidal energy redistribution. Tidal flats store and dissipate tidal energy, with the former being much more important than the latter. The loss of these functions due to tidal flat reclamation will lead the additional tidal energy to be redistributed. Furthermore, we demonstrate that after substantial reclamation on the Chinese Jiangsu coast, far-field impacts on tidal dynamics will be seen on Korea's west coast. Reclamation on Korea's west coast, in turn, may have far-field impacts on China's shore. Reclamation in the BYECS has the potential to increase tidal amplitude and sediment movement onshore. The former may exacerbate coastal dangers including storm surge, while the latter could lead to significant siltation. As a result, any planned manmade modifications to the tidal flat must always be carefully considered, considering the impacts on both the local ecosystem and farther away.