Tidal variation m the west coastal area of Sri Lanka.

Abstract

The present study was carried out in an attempt to observe and analyze the tidal height changes due to the motion of the sun, moon and earth, in the west coastal area of Sri Lanka. Tidal height deviations from the Mean Sea Level (MSL) were measured every 15 minutes throughout the year 2015 using the tide pole installed in the sea, 100m away from Colombo Fort, which was built by the Hydrography Survey Unit of the Sri Lanka Navy. Using the obtained data, the behaviour of tidal waves was identified. The main tidal constituents were obtained using the Fast Fourier Transformation (FFT) and the Interpolation method. The mean value of the High Water Level (MHWL) and the mean value of the Low Water Level (MLWL) of the tides were then calculated for each month of the year. These mean values were used to update the Mean Sea Level (MSL). The main tidal constituents for each month were then used to identify the behaviour of tidal waves.