The risk of ignorance of DEM Height Reference System on coastal inundation modeling (the case of Jakarta) Heri Andreas, Firman Juliandri, Dhota Pradipta, Dina Anggreni Sarsito, Hasanuddin Z Abidin
Institute of Technology Bandung
Abstract
As a result of continuing land subsidence which is also followed by sea level rise, some lowland coastal areas will experience coastal inundation. The lowlands will gradually become lower than sea level at high tide and even during normal conditions. Some areas where when it is not high tide experience coastal inundation permanently. Coastal inundation modeling is important to do so that we get potential hazards and disaster risks from the occurrence of it. With coastal conditions that are usually inhabited by many people, become economic centers and others, then when coastal inundation occurs, material losses will certainly occur as well. To create a coastal inundation model, parameters are needed including the Digital Elevation System (DEM). The coastal lowlands are represented from the DEM. From the corrected DEM for land subsidence, sea level rise and tidal hydraulic models, we will get a coastal inundation model. The most important thing related to this is the accuracy of the DEM itself and the height of the reference system. If we don^t use an accurate DEM, and don^t use the height reference system correctly (should be High Tide or Mean Sea Level), then we won^t get a good coastal inundation model. The impact is that we will not be correct map the hazards and disaster risks due to the coastal inundation. This paper will demonstrate the risk when we ignore the height reference system, so that we get a miss leading in the dangers and risks of coastal inundation in Jakarta as a case study area.
