Sea level trend and variability around the Peninsular Malaysia
Q. H. Luu, P. Tkalich, and T. W. Tay
Tropical Marine Science Institute, National University of Singapore, Singapore
Received: 16 April 2014 – Accepted: 15 May 2014 – Published: 17 June 2014
Correspondence to: Q. H. Luu (
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Published by Copernicus Publications on behalf of the European Geosciences Union.
Abstract
Peninsular Malaysia is bounded from the west by Malacca Strait and the Andaman Sea both connected to the Indian Ocean, and from the east by South China Sea being largest marginal sea in the Pacific Basin. Resulting sea level along Peninsular 5 Malaysia coast is assumed to be governed by various regional phenomena associated with the adjacent parts of the Indian and Pacific Oceans. At annual scale, sea level anomalies (SLAs) are generated by the Asian monsoon; interannual sea level variability is determined by the El Niño–Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD); while long-term sea level trend is related to global cli10 mate change. To quantify the relative impacts of these multi-scale phenomena on sea level trend and variability around the Peninsular Malaysia, long-term tide gauge record and satellite altimetry are used. During 1984–2011, relative sea level rise (SLR)
rates in waters of Malacca Strait and eastern Peninsular Malaysia are found to be 2.4±1.6mmyr−1 and 2.7±1.0mmyr−1, respectively. Allowing for corresponding verti15 cal land movements (VLM; 0.8±2.6mmyr−1 and 0.9±2.2mmyr−1), their absolute SLR rates are 3.2±4.2mmyr−1 and 3.6±3.2mmyr−1, respectively. For the common period 1993–2009, absolute SLR rates obtained from both tide gauge and satellite altimetry in Peninsular Malaysia are similar; and they are slightly higher than the global tendency. It further underlines that VLM should be taken into account to get better estimates of SLR 20 observations. At interannual scale, ENSO affects sea level over the Malaysian coast in the range of ±5 cm with a very high correlation. Meanwhile, IOD modulates sea level anomalies mainly in the Malacca Strait in the range of ±2 cm with a high correlation coefficient. Interannual regional sea level drops are associated with El Niño events and positive phases of the IOD index; while the rises are correlated with La Niña episodes 25 and the negative periods of the IOD index. Seasonally, SLAs are mainly monsoondriven, in the order of 10–25 cm. Geographically, sea level responds differently to the monsoon: two cycles per year are observed in the Malacca Strait, presumably due to South Asian-Indian Monsoon; whereas single annual cycle is noted along east coast 1520
Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | of Peninsular Malaysia, mostly due to East Asian-Western Pacific Monsoon. These results imply that a narrow topographic constriction in Singapore Strait may separate different modes of annual and interannual sea level variability along coastline of Peninsular Malaysia.
