Hiroshi Takagi - School of Environment and Society, Tokyo Institute of Technology, Tokyo, Japan
Miguel Esteban - Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan
Takahito Mikami - Dep. of Civil and Environmental Engineering, Waseda University, Tokyo, Japan,
Daisuke Fujii - School of Environment and Society, Tokyo Institute of Technology, Tokyo, Japan

Jakarta, the capital of Indonesia, is one of the largest coastal megacities in the planet. Although Jakarta has been facing many urban development issues, the issue of landsubsidence appears to have become especially serious over the last couple of decades. Recently, Takagi et al. investigated two distinctive mechanisms of coastal floodsin Jakarta, hereinafter referred to as widespread coastal flood [1] and dyke-break induced tsunami [2], both of which are exacerbated by land subsidence. The presentwork will introduce both of these studies, and discuss how rapid land subsidence could have serious impacts on unprepared parts of Jakarta city.