Latitude-Time Total Electron Content Anomalies as Precursors to Japan's Large Earthquakes Associated with Principal Component Analysis

摘要: The goal of this study is to determine whether principal component analysis (PCA) can be used process latitude-time ionospheric TEC data on a monthly basis identify earthquake associated anomalies. PCA applied (mean-of-a-month) total electron content (TEC) records collected from the Japan GEONET network detect anomalies with 18 earthquakes in (M≥6.0) 2000 2005. According results, was able discriminate clear months when all occurred. After reviewing no M≥6.0 occurred but geomagnetic storm activity present, it possible that maximal eigenvalues returned for these indicate Previously has been earthquake-associated recognized by other researchers, who found statistical association between large and could established 5 days before nucleation; however, since uses characteristics related anomalies, show such existed earlier than 5-day window.