The impacts of coastal subsidence and sea level rise in coastal city of semarang (Indonesia)
Abidin H.Z.a, Andreas H.a, Gumilar I.a, Fukuda Y.b, Nurmaulia S.L.a,b, Riawan E.c, Murdohardono D.a,d, Supriyadie
a Geodesy Research Group, Faculty of Earth Science and Technology, Institute of Technology Bandung, Bandung, Indonesia
b Graduate School of Science, Kyoto University, Japan
c Institute of Physical Geodesy, Darmstadt University of Technology, Darmstadt, D-64287, Germany
d Centre for Groundwater Resources and Environmental Geology, Geological Agency of Indonesia, Bandung, Indonesia
e Dept of Physics, Semarang State University, Semarang, Indonesia
Abstract
© 2012 by World Scientific Publishing Co. Pte. Ltd. All rights reserved.Semarang is the capital of Central Java province, located in the northern coast of Java island, which has a population of about 1.5 million. In general, the Leveling surveys, GPS surveys, Microgravity surveys, and InSAR technique, conducted from 1999 to 2011, determined that land subsidence in Semarang exhibits spatial and temporal variations, with the rates of about 1 to 19 cm/year. The largest subsidence occurred at several areas along the coast. This subsidence is mainly due to excessive groundwater extraction, natural consolidation of alluvial, and load of constructions. During the high tide periods, these subsiding areas used to experience flooding. This paper discusses the correlation between coastal subsidence and flooding phenomena along these coastal areas of Semarang, along with sea level rise phenomena in the Java sea. In this case, the sea level rise rates are obtained from altimetry observation.