Recent Sea Level Rise and Variability in Singapore Region Derived from Tide Gauges and Satellite Altimetry

Abstract

Sea level in the Southeast Asia (SEA) seas is driven by various phenomena at global,  regional and local scales. The latest tide gauge and satellite data revealed its most recent spatial and temporal patterns. The trend of global sea level rise in Singapore region is hindered by dominant variability of El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Indian Ocean Dipole (IOD), as well as associated modulation of Asian Monsoon. It was confirmed that positive sea-level anomalies in the southern and western areas of Southeast Asia seas were significantly high (~10 cm) during the northeast monsoon, especially in the Gulf of Thailand (~25 cm). The sea level trends for these regions were basically reversed during the southwest monsoon but with a smaller magnitude of negative sea-level anomalies. The regional sea-level trend in the Sunda Shelf differed from region to region, with the rates varied greatly from 1.4 to more than 4.8 mm/year. Interestingly, the rates on the east-western side of the region were roughly 3.0-4.5 mm/year, which were higher than the ones at other regions, being 2.5-3.5 mm/year. The presentation discuss the causes and consequences of sea level rise and variability in SEA and Singapore region in particular. This Research is supported by Singapore’s National Research Foundation and National Environment Agency under the National Sea Level Programme Funding Initiative (Award No. USS-IF-2020-4).