Numerical Study of Principal Tidal Constituents in the Gulf of Thailand and the Andaman Sea

This study examined numerical principal tidal constituents in the Gulf of Thailand and the Andaman Sea. The principal tidal constituents (K1, O1, M2 and S2) were calculated using a Harmonic method. These constituents were used to estimate the Form Factor (F). The simulated results from the Harmonic method were compared with the Moon phase in a 31-days cycle to verify our Harmonic model. We used observed water level data from 21 stations in the Gulf of Thailand and the Andaman Sea from both Hydrographic and Marine Departments. The tide types composed of (1) diurnal, (2) mixed with predominantly diurnal and (3) mixed with predominantly semidiurnal at 15 stations at the Gulf of Thailand coastline and semidiurnal at six stations of the Andaman Sea coastline. The Moon phase influenced tidal constituents in all stations, except the following 8 stations: Ko Prap (Surat Thani), Pakpanang (Nakhon Si Thammarat), Songkhla, Paknam Pattani (Pattani), Paknam Bangnara (Narathiwat), Paknam Ranong (Ranong), Ao Tublamu (Phangnga) and Paknam Krabi (Krabi) stations.