Determination of a localized mean sea surface model for Malaysian seas using multi-mission satellite altimeter

Abstract

Mean Sea Surface (MSS) is the displacement of the sea surface in respect to a numerical model of the earth and it nearly takes after geoids. However, the coastal tide gauges provided to certain coastal areas are limited to ocean studies. Tide gauges are usually installed at coastal areas and only a few stations have long records and adequate geographical distribution. To solve these problems, the use of Satellite Altimeter technology is required. The aim of this study was to produce a new localized mean sea surface model over Malaysian seas using multi-mission satellite altimeters from 1993 to 2017. To understand variations in SSH during the monsoon season, sea surface height climatology data were generated and the average sea surface height data were used to determine the localized MSS of Malaysian Seas. Satellite altimeters are important to producing MSS models that support oceanographic and geophysical studies such as sea level rise studies and tidal predictions. A comparison between altimetry data and tide gauge observations showed good agreement with correlations higher than 0.9 and a Root Mean Square Error (RMSE) lower than 0.1 meter. Then, a localized mean sea surface model was generated using the spatial average of SSH climatology data for a 25 year time period to obtain a high-resolution MSS model. Localized MSS is an important reference for several applications such as charting datum, sea level change, and derivation of mean dynamic topography.