Possible Spatial Extent of Ionospheric GPS-TEC and NmF2 Anomalies Related to the 1999 Chi-Chi and Chia-Yi Earthquakes in Taiwan
Scientists analyzed temporal variations of local data recorded in Taiwan and reported anomalous reductions in the ionospheric to talelectron content (TEC) on days 4 and 3 be fore (17 and 18 September) the Chi-Chi earthquake (Mw 7.6, ML 7.3), and days 3 and 1 prior to (19 and 21 October) the Chia-Yi...
Main Authors: | , , , |
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Format: | Article |
Language: | English |
Published: |
Chinese Geoscience Union
2009-01-01
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Series: | Terrestrial, Atmospheric and Oceanic Sciences |
Subjects: | |
Online Access: |
http://tao.cgu.org.tw/images/attachments/v206p769.pdf
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Summary: | Scientists analyzed temporal variations of local data recorded in Taiwan and reported anomalous reductions in the ionospheric to talelectron content (TEC) on days 4 and 3 be fore (17 and 18 September) the Chi-Chi earthquake (Mw 7.6, ML 7.3), and days 3 and 1 prior to (19 and 21 October) the Chia-Yi earthquake (ML 6.4) in Taiwan. In this paper, we propose a spatial analysis which compares the data recorded inside and outside of the earthquake area around Taiwan to discriminate whether the anomalies are local (earth quake related) or global (non-earth quake related) phenomena. Results suggest that the anomalies appearing day 3 before the Chi-Chi earthquake, and days 3 and 1 before the Chia-Yi earthquake are local (earthquake related) phenomena and the anomaly appearing on 17 September 1999 (day 4 be fore) might be the result of both global phenomena (i.e., a geomagnetic storm) and the local effect of the Chi-Chi earthquake. |
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ISSN: | 1017-0839 2311-7680 |