Latitude-Time Total Electron Content Anomalies as Precursors to Japan's Large Earthquakes Associated with Principal Component Analysis
Figure 3
(a) shows the latitude-time TEC records in Japan for 2003 (Unit: TECu). (b) shows 12 principal eigenvalues in 2003. Three larger principal eigenvalues are represented in May, September, and October in which four earthquakes occurred on May 26, September 25, October 8, and October 31 (Table 1).
