KAJIAN PEMBANGUNAN DATUM VERTIKAL NIRKELIM UNTUK HIDROGRAFI DI DELTA MAHAKAM, KALIMANTAN TIMUR

• Main Author: Rizqy Hafizh, Farras
• Format: Theses
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/81569
• Institution: Institut Teknologi Bandung

Seamless vertical datum surface in hydrography has wide-ranging potential applications in surveying and navigation. Such surfaces form an integral part of the so-called Hydrographic Separation Model (HSM), enabling transformation between vertical datum surfaces, e.g., the Mean Sea Level (MSL) and the Lowest Astronomical Tide (LAT) through the ellipsoid. In this study, a study on the construction of vertical datum surfaces comprising of seamless MSL surface and seamless LAT surface is conducted in the Mahakam Delta. Three global Mean Sea Surface (MSS) models and a regional tide model from the Geospatial Information Agency of Indonesia are used in the establishment of MSL and LAT surfaces, respectively. The DTU21 MSS performs best compared to the CLS15 and SDUST2020 MSS in the Mahakam Delta, indicated by the smallest mean of absolute error (MAE) value of 0.326 m against the 8 permanent tidal gauging stations. LAT surface from the tide model is found to have MAE value of 0.125 m. Interpolation of MSL and LAT values from 6 permanent tidal gauging stations are utilized to create the seamless surfaces known as the MSLoid and LAToid, respectively. Inverse Distance Weighted (IDW), spline, kriging, and triangulation with linear interpolation methods with various parameters are used. When compared at the 2 stations not used in the interpolation, the kriging interpolation MSLoid has the superior agreement compared to other MSL surfaces with MAE of 0.287 m. Kriging LAToid performs the best compared to other LAT surfaces indicated by MAE of 0.083 m. An alternative method is recommended to generate a surface that better captures the tidal complexities of the area, here the use of hydrodynamic modelling is proposed. Seamless LAT surface from BIG tide model is applied as the chart datum (CD) in a navigation scenario in an area where under-keel clearance is critical. Compared to the previous chart datum, the optimized CD from the seamless surface resulted in an increase in operation window of 11 out of 30 days.