Tide-Surge Interaction near Singapore and Malaysia using a Semi-empirical Model

Abstract. Tide-surge interaction (TSI) plays a substantial role in determining the characteristics of surges over shallow regions. A variety of approaches have been used to study TSI globally, and TSI have been found to occur in Singapore and the east coast of Peninsular Malaysia. However, the characteristics of TSI in Singapore and the east coast of Peninsular Malaysia have yet to be studied in detail. We study the TSI at seven tide gauges along the east coast of Peninsular Malaysia and Singapore. Here, we propose a modified statistical framework that accounts for irregularity in the tidal cycle. We find evidence of TSI at all seven locations, with characteristics varying smoothly along the coastline: the highest non-tidal residuals are found to occur most frequently before tidal high water at the southern region of this coastline and in Singapore, both before and after tidal high water in the middle of the coastline, and after tidal high water at the northern region. We also propose a semi-empirical model to investigate the effects of tidal phase alteration, which is one the mechanisms of TSI. Results of our semi-empirical model reveal that tidal phase alteration caused by wind-driven surges is substantial enough to generate significant change in the timing of the largest surges.