Abstract:We use the global ionospheric maps(GIMs) provided by international GNSS service(IGS) to analyze the total electron content(TEC) changes during the storm on August 26, 2018. We use the sliding interquartile rang method to extract the disturbance characteristics of the global TEC, and discuss the response mechanism of the ionospheric disturbance caused by this storm. The results show: 1)The ionospheric TEC is a mainly positive disturbance except in the Arctic region during the main phase of the storm. TEC shows a long-term negative disturbance in the northern hemisphere during the recovery phase, but it is opposite in the southern hemisphere. 2) The ionospheric TEC disturbance caused by the storm is related to the change of thermosphere O/N2 ratio. The eastward prompt penetration electric field(PPEF) has a great influence on the global daytime ionospheric TEC positive disturbance during the period when the Bz component of interplanetary magnetic field is southward; the sedimentation of high energy particles may be the cause of the positive disturbance of TEC in high latitude and polar regions. The seasonal circulation between summer and winter promotes the north-south asymmetric response of global ionospheric TEC during the recovery phase of the storm.
ZHU Juntao,LIU Yusheng,LIN Zhiyu et al. Response Analysis of Global Ionospheric TEC to Geomagnetic Storms from August 25~29, 2018[J]. jgg, 2022, 42(7): 661-668.