Publication Date:
2004-04-08
Description:
In this paper we examine pre-earthquake ionospheric anomalies by the total electron content (TEC) derived from a ground-based receiver of the Global Positioning System (GPS). A 15-day running median of the TEC and the associated inter-quartile range (IQR) are utilized as a reference for identifying abnormal signals during all of the 20M≥6.0 earthquakes in the Taiwan area from September 1999 to December 2002. Results show that the pre-earthquake ionospheric anomalies appear during 18:00–22:00LT (LT=UT+8h) within 5 days prior to 16 of the 20M≥6.0 earthquakes. This success rate of 80% (=16/20%) suggests that the GPS TEC is useful to register pre-earthquake ionospheric anomalies appearing before large earthquakes. Key words. Ionosphere (ionospheric disturbances; ionosphere-atmosphere interactions)
Print ISSN:
0992-7689
Electronic ISSN:
1432-0576
Topics:
Geosciences
,
Physics
Permalink