DEVELOPMENT OF REGIONAL TIDE MODEL FOR REALIZATION OF INDONESIAN PRECISE MARINE GEOID

• Main Author: Syahrullah Fathulhuda, Muhammad
• Format: Dissertations
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/81479
• Institution: Institut Teknologi Bandung

Indonesia's precise marine geoid, with an accuracy better than 5 cm, is required as a fundamental infrastructure for surveying and engineering activities. Currently, satellite altimetry has proven its usefulness in determining the sea geoid in large maritime areas with high spatial resolution, reliable accuracy, and freely available data. However, the effect of ocean tides on satellite altimetry data still contributes significantly to errors in determining the sea geoid, especially in shallow coastal areas. Therefore, precise determination of the sea geoid requires a precise ocean tidal model. For a sea geoid with an accuracy better than 5 cm in coastal and shallow water areas, a tidal model with better accuracy than 15 cm is needed. This research aims to develop an Indonesian tidal model using altimetry data along observation paths, utilizing multi-satellite altimetry known as an empirical tidal model. The goal is to improve the resolution of the tidal model and maintain shortwave signals in Indonesian waters. Additionally, the modeling process will involve evaluating the accuracy of each altimetry satellite's data to determine the most optimal satellite combination for modeling. Furthermore, the resulting tidal model will be analyzed for its impact on marine geoid estimation errors. The outcomes of the tidal model development undertaken in this research reveal that a combination of satellite data from the TOPEX/Jason series (TOPEX, Jason- 1, Jason-2, Jason-3, SENTINEL-6A), GFO, and ENVISAT, along with tide gauge stations, emerges as the most effective configuration. This amalgamation yields a model exhibiting superior precision compared to the global tidal model, achieving an accuracy of 11.38 cm. This serves as empirical evidence supporting the notion that enhanced model accuracy can be attained through the implementation of satellite combination selection procedures. On the contrary, concerning Indonesia's required precision of the marine geoid, which stands at a level better than 5 cm, this level of precision does not fall within the range of error propagation resulting from the marine geoid precision, which is between 5 to 6 cm. This indicates that the precision of the generated tidal model is insufficient to meet Indonesia's requirements. Considering the upper limit of this range, there exists a probability of achieving a precision lower than 5 cm. Therefore, achieving meticulous marine geoid realizations necessitates consideration of parameters beyond the precision of the tidal model.