Spatial and Temporal Response of Equatorial Ionization Anomaly to the 17 March 2015 Storm from Global Ionosphere Map
MEI Xuefei, LUO Weihua, CAI Hongtao, ZHU Zhengping1. School of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China; 2. College of Electronic Information and Engineering, South- Central University for Nationalities, Wuhan 430074, Hubei, China
The responses of Equatorial Ionosphere Anomaly (EIA) to the storm occurred on 17 March 2015 were studied using Global Ionosphere Map (GIM). The variations of Total Electron Content (TEC), latitudinal TEC gradients and the rate of latitudinal TEC gradients in EIA regions were investigated in 75E, 110E and -60E longitudinal sectors. The results from the GIM data showed that the distributions of the latitudinal gradient of TEC became monotonous in three longitudes on 18 March (the first day of the recovery phase), but the variations were different. On 18 March, the magnitudes of latitudinal gradients decreased in spatial and temporal in 75E and 110E, which means the EIA was suppressed during the recovery phase of the storm, especially in 110E. The magnitudes of latitudinal TEC gradients showed an obvious increase in spatial and temporal in -60E. The SAMI2 reproduced the suppression of EIA with a disturbance dynamo electric field, which indicated that the physical process controlled the behaviors of the plasma during the recovery phase of the storm.
Key words:ionosphere; Equatorial Ionization Anomaly; storm; Global Ionosphere Map
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