Potential vulnerability impact of coastal inundation over Kelantan coast due to sea level rise based on satellite altimetry, GPS and LiDAR data

Global sea level is expected to rise consistently in the future, causing severe damage to the coastal areas and threatening nearby populations. Malaysian coast has numerous low-lying areas, which are at risk of inundation resulting from the increment of sea level, particularly in Kelantan coast. In this study, the potential vulnerability impact of sea level rise has been evaluated using the combination of data from satellite altimeters: global positioning system (GPS) and light detection and ranging (LiDAR). According to our findings, the coastal areas of Kelantan are potentially inundated by sea water in several locations, thus affecting the socio-economy and life of the coastal community. The inundation scenarios for 5, 25, 45, 65 and 85 years of return periods have been successfully simulated using the hydrological model obtained from altimetry data. Subsequently, the inundation scenarios have been overlaid on land elevation datasets to estimate the inundation risks. In order to develop maps for vulnerable areas and populations, vulnerability assessments of inundation risk maps are analysed in ArcGIS environment. The study reveals that the projection of sea level rise is between 32 and 50 cm for the specific area of the Malaysian seas by 2100. The results of the assessment show that the coastal zone of Kelantan is highly vulnerable to the sea level rise. Almost 1km 2 of the total land area has been projected to be inundated in the least scenario on local scale. Under the higher sea level scenarios, more than 8.2km 2 of the land area are potentially inundated. Up to 46,000 peoples could be affected around the Kelantan coastal and floodplain area, particularly near Kota Bharu. This study highlights the integration of hydrological model to produce inundation risk map that consider the extent of total land area covered by sea level rise in different scenarios.