Latitude-Time Total Electron Content Anomalies as Precursors to Japan's Large Earthquakes Associated with Principal Component Analysis
Figure 2
(a) shows the latitude-time TEC record in Japan for October 2000 (JST: Japanese Standard Time) (Unit: TECu). (b) shows 12 principal eigenvalues in 2000. Dates constitute the horizontal axis and corresponding eigenvalues are on the vertical axis. Peaks and troughs in eigenvalues have been plotted and graphed on a month-to-month basis to allow for interpolation. The largest principal eigenvalue is represented in October in which an earthquake occurred on October 6 (Table 1).
