Tidal propagation based on Co-Phase chart and Co-Range chart in Sunda Strait, Indonesia

Abstract

The characteristic of tide is different for each region. Co-tidal charts are one of the media to present an information about the character of tidal. There are two types of co-tidal chart, such as co-phase chart and co-range chart. Co-phase chart will show the distribution of tides, meanwhile the co-range chart will show the propagation direction of tides. Sunda Strait was chosen to analyze the tidal propagation pattern. The amount of the tidal station which were observed are 33 stations across Sunda Strait. This research used four harmonic constituents of tide, such as M2, S2, K1 O1 and the chart of Sunda Strait to establish co-tidal charts. The harmonic constituent of tide was analyzed by Admiralty Method. These data were obtained from Hydrography and Oceanography Center, Indonesian Navy (PUSHIDROSAL). The result of this research shows the tidal propagation direction of semidiurnal harmonic constituents of tide (M2, S2) that flows in south area of Sunda Strait (comes from Indian Ocean through the western part of Sumatra island). Meanwhile, in north area of Sunda Strait, the tidal propagation that comes from Indian Ocean flows through Karimata Strait. The direction of tidal propagation of diurnal harmonic constituents of tide (K1, SO1) that flows in Sunda Strait comes from Pacific Ocean through Karimata Strait. However, the tidal type in Sunda Strait is dominated by mixed tide prevalling semidiurnal and the highest amount of Z0 is 100 cm, meanwhile the lowest value of Z0 in Sunda Strait is 40 cm.