Seasonal variability of hydrodynamics in Anmok coastal waters

Abstract

The waves and currents observed by acoustic AWAC, VECTOR, Aquadopp Profiler were analysed to account for the variability of the wave and current. The measured data was processed in two aspects: long term hydrodynamic data observed by AWAC at the water depth of 18 m (W1) and surf-zone intensive measurement observed by other instruments. The data observed in the surf-zone were suitable for analysing the sediment transport because the data contains profiling and point data from the water depth of 25 cm. Based on the data at point W1, the analysed result shows that waves of NE and ENE directions are dominant in summer season and that waves of NNE and NE directions are dominant in winter season. The direction of tidal current shows a reciprocating motion parallel to the coastline. The high waves show that waves of NE direction, which is perpendicular to the coastline, are dominant due to north-easterly winds and wave propagation in winter. The directions of wave-induced current near bottom water depth of 25 cm are different both in horn and bay due to the crescentic bars in surf-zone and beach cusp in Anmok.t the water depth of 18 m (W1) and surf-zone intensive measurement observed by other instruments. The data observed in the surf-zone were suitable for analysing the sediment transport because the data contains profiling and point data from the water depth of 25 cm. Based on the data at point W1, the analysed result shows that waves of NE and ENE directions are dominant in summer season and that waves of NNE and NE directions are dominant in winter season. The direction of tidal current shows a reciprocating motion parallel to the coastline. The high waves show that waves of NE direction, which is perpendicular to the coastline, are dominant due to north-easterly winds and wave propagation in winter. The directions of wave-induced current near bottom water depth of 25 cm are different both in horn and bay due to the crescentic bars in surf-zone and beach cusp in Anmok.