Ionospheric GPS TEC anomalies and M ≥ 5.9 earthquakes in Indonesia during 1993 - 2002

Sarmoko Saroso, Jann Yenq Liu, Katsumi Hattori, Chia Hung Chen

Research output: Contribution to journalArticlepeer-review

35 Scopus citations


Indonesia is one of the most seismically active regions in the world, containing numerous active volcanoes and subject to frequent earthquakes with epicenters distributed along the same regions as volcanoes. In this paper, a case study is carried out to investigate pre-earthquake ionospheric anomalies in total electron content (TEC) during the Sulawesi earthquakes of 1993 - 2002, and the Sumatra-Andaman earthquake of 26 December 2004, the largest earthquake in the world since 1964. It is found that the ionospheric TECs remarkably decrease within 2 - 7 days before the earthquakes, and for the very powerful Sumatra-Andaman earthquake, the anomalies extend up to about 1600 km from the epicenter.

Original languageEnglish
Pages (from-to)481-488
Number of pages8
JournalTerrestrial, Atmospheric and Oceanic Sciences
Issue number5
StatePublished - Oct 2008


  • GPS TEC (Total Electron Content)
  • Pre-earthquake-related anomaly
  • The 2004 Sumatra-Andamann
  • The Sulawesi earthquakes


Dive into the research topics of 'Ionospheric GPS TEC anomalies and M ≥ 5.9 earthquakes in Indonesia during 1993 - 2002'. Together they form a unique fingerprint.

Cite this