The simulation of the observation data in predicting tidal patterns using the Admiralty method in Dumai’s harbour

Department of Civil Engineering, Universitas Riau, Pekanbaru, Indonesia

^* Corresponding author: andy.hendri@lecturer.unri.ac.id

Abstract

In this paper, we have discussed the tidal analysis conducted using the Admiralty method with 15 days of tidal data as the research object. Due to the long tidal data period, the analysis was conducted in order to determine the proper time to collect the data for future tidal predictions. This data has to be adequate for its realisation in reality. The used data was collected from the Geospatial Information Association and the location of this research study was Dumai’s Harbour. The study started on July 13^th, 2014 and ended on December 8^th, 2014. For verification, the used data started from June 13^th, 2016 and ended October 31^st, 2016. From the 135 simulations, we determined that the magnitude of the Root Mean Square Error (RMSE) was 106.2. In order to produce well-predicted tidal results, the collection of the tidal data was best started during the phase of the crescent moon (which begins on the 24^th based on the Hijriah calendar). On these dates, the RMSE reached the lowest value with a magnitude of 74.76. This result could be used as a reference when choosing the proper time to collect the observation data and also for predicting the tidal patterns at the location.