Abstract This study investigates the morphology of the GPS TEC responses in the African Equatorial Ionization Anomaly (EIA) region to intense geomagnetic storms during the ascending and maximum phases of solar cycle 24 (2012 - 2014). Specifically, eight intense geomagnetic storms with Dst ≤ -100nT were considered in this investigation using TEC data obtained from 13 GNSS receivers in the East African region within 36–42°E geographic longitude; 29°N–10°S geographic latitude; ± 20°N magnetic latitude. The storm-time behavior of TEC shows clear positive and negative phases relative to the non-storm (median) behavior, with amplitudes being dependent on the time of sudden commencement of the storm and location. When a storm starts in the morning period, total electron content increases for all stations while a decrease in total electron content is manifested for a storm that had its sudden commencement in the afternoon period. The TEC and the EIA crest during the main phase of the storm is significantly impacted by the geomagnetic storm, which experiences an increase in the intensity of TEC while the location and spread of the crest usually manifest a poleward expansion.

中文翻译：

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非洲赤道电离异常（EIA）对太阳活动周期最大阶段某些选定强地磁暴的响应 24

摘要 本研究调查了非洲赤道电离异常 (EIA) 地区 GPS TEC 对太阳活动周期 24 (2012 - 2014) 上升阶段和最大阶段强烈地磁风暴的响应形态。具体而言，本次调查使用从东非 36-42°E 地理经度内的 13 个 GNSS 接收器获得的 TEC 数据考虑了 Dst ≤ -100nT 的八个强烈地磁暴；29°N–10°S 地理纬度；± 20°N 磁纬度。相对于非风暴（中值）行为，TEC 的风暴时间行为显示出明显的正负相位，幅度取决于风暴突然开始的时间和位置。当暴风雨在早上开始时，所有台站的总电子含量增加，而在下午突然开始的风暴则表明总电子含量减少。风暴主要阶段的TEC和EIA波峰受到地磁暴的显着影响，TEC强度增加，而波峰的位置和扩展通常表现出向极地扩展。