Somboon Pornpinatepong

pp. 425 - 431

Abstract

The comprehensive understanding of tidal circulation in the Andaman Sea plays an essential role in
search and rescue programs. The accurate prediction of water particle trajectories under influence of the
tidal force will speed up searching for a floating object. A 2-D vertically-averaged hydrodynamic model has
been applied to the southern west coast of Thailand covering the area from 0ºN, 95ºE to 17ºN, 104ºE. The
modelís forces are the seven predominant tidal constituents (M2, S2, N2, K2, K1, O1 and P1), derived from
Oregon State University. Comparison between the computed and observed water surface elevation reported
by Royal Thai Navy showed good agreement. The model then has been employed to simulate the tidal current
along the western coast of Thailand. The prediction of elliptic water-particle orbits was confirmed by two
patterns found. In the open ″bay″ between Satun and Krabi, the orbits would have various orientations, with
displacement of 3 km, whereas in the open sea between Phanga and Ranong, the particles moved mainly in
the east-west direction with a maximum displacement of 5-6 km.