Ionospheric Anomalies Related to the (M=7.3), August 27, 2012, Puerto Earthquake, (M=6.8), August 30, 2012 Jan Mayen Island Earthquake, and (M=7.6), August 31, 2012, Philippines Earthquake: Two-Dimensional Principal Component Analysis

• Published in: The Scientific World Journal
• Main Author: Lin, Jyh-Woei
• Other Authors: Department of Earth sciences
• Format: Article in Journal/Newspaper
• Language: English
• Published: Hindawi Publishing Corporation 2013
• Subjects: Jan Mayen; Jan Mayen Island
• Online Access: https://doi.org/10.1155/2013/271513; http://ir.lib.ncku.edu.tw/handle/987654321/147194; http://ir.lib.ncku.edu.tw/bitstream/987654321/147194/-1/index.html

Two-dimensional principal component analysis (2DPCA) and principal component analysis (PCA) are used to examine the ionospheric total electron content (TEC) data during the time period from 00: 00 on August 21 to 12: 45 on August 31 (UT), which are 10 days before the M = 7.6 Philippines earthquake at 12:47:34 on August 31, 2012 (UT) with the depth at 34.9 km. From the results by using 2DPCA, a TEC precursor of Philippines earthquake is found during the time period from 4: 25 to 4: 40 on August 28, 2012 (UT) with the duration time of at least 15 minutes. Another earthquake-related TEC anomaly is detectable for the time period from 04: 35 to 04: 40 on August 27, 2012 (UT) with the duration time of at least 5 minutes during the Puerto earthquake at 04: 37: 20 on August 27, 2012 (UT) (M-w= 7.3) with the depth at 20.3 km. The precursor of the Puerto earthquake is not detectable. TEC anomaly is not to be found related to the Jan Mayen Island earthquake (M-w = 6.8) at 13: 43: 24 on August 30, 2012 (UT). These earthquake-related TEC anomalies are detectable by using 2DPCA rather than PCA. They are localized nearby the epicenters of the Philippines and Puerto earthquakes.