Evaluating accuracy of tidal datum level using spatial interpolation

On this research, in terms of analysis in sea-level rising and vessel security, we carried on our research in datum level status and calculating methods for vertical datum. We construct tidal model using spatial interpolation which shows relating datum level depending on region with local mean sea level and validating accuracy of tidal model. The object region of this research was selected by tidal gap and geographic feature classified in the West sea. In the result of test, there are deviation under 3 cm between real survey value and estimate value through spatial interpolation in East sea, under 10 cm of deviation between survey value and estimate value in South sea, and under 15 cm of deviation between survey value and estimate value in West sea. In this test, we could analyze accuracy of estimate value and we could derive suitable spatial interpolation for datum level as RMSE. In four spatial interpolations, Spline has most stable result which is 4.35 cm. After that, there need development of specific tidal model considered coastline, underwater geography, and islands etc.