Predicting coastal inundation triggered by the oceanic forcing across Jakarta Bay

Abstract

Coastal inundation becomes a severe hazard to many world’s cities near shorelines. A recent publication by the Intergovernmental Panel on Climate Change (IPCC) in 2021 projected the increase in mean sea level and the probability of extreme waves in the future that would add more pressure to the cities like Jakarta, Indonesia. Hence, the estimations of the region’s vulnerability due to the hazard are critical steps for designing the adaptation measures. The study is aimed to spatially estimate the future coastal flooding in Jakarta Bay caused by oceanic forcing under the IPCC 2021 scenarios, including the High Highest Water Level (HHWL), the predicted sea level rise by 50 years, the extreme wave setup, and the infragravity (IG) waves. The spatial inundation is generated by projecting the estimated total water level to the Jakarta region’s Digital Surface Model (DSM) and further overlaid on the rectified Google Earth image. The result shows that the increase in water level due to climate change may reach ~1.8 m, increasing the spatial inundation area around the Jakarta shoreline by 37 %. Considering the severe impacts of the projected inundation, the decision-makers need to focus on adaptation efforts soon.