Perturbation Analysis of the Ionospheric TEC before and after the Wenchuan Earthquake
汶川大地震前后电离层电子含量的扰动分析

To analyze the variation of the ionospheric total electron content (TEC) around the earthquakes, we select the ionospheric TEC of 10 days before and after the Ms8.0 earthquake that occurred on May 12, 2008 in Wenchuan as our research object. Adopting the statistical analysis method, the Ionopsheric VTEC data during the earthquake has been analyzed and discussed in detail, using the VTEC data offered by IGS, together with the solar and geomagnetic information. Numerical results show that obvious TEC disturbance existed before the great earthquake, and the abnormal variations of the ionospheric TEC may be precursors to the earthquake.