The Characteristics of the Abnormal Day-to-Day TEC Variation above East Asian Region

We investigate the abnormal day-to-day variability of total electron content (TEC) over 60 Global Navigation Satellite System (GNSS) stations above East Asian region from 2012 to 2018 and find that positive anomalies occur more frequently at middle latitude about LT 14–20 around 28° N 22–00. The negative 10–02, they obviously less 15° N~30° 08–12, near 22° 14–18. quantities are comparable. direction moving is east west in a zonal all conditions. speeds 15~19 degrees per hour seem grow as increases. TEC 22.1% temporal bins before large earthquakes within seven days 24% interval, which one day three later than main phase geomagnetic storms. Further work necessary determine sources these anomalies.