We report on an extreme ionospheric plasma density enhancement and Global Positioning System (GPS) scintillation at dawn, observed within the expanding equatorial ionization anomaly (EIA). The total electron content (TEC) in central America reached 50 TECu at sunrise, the value almost twice as high as the normal afternoon peak. The enhanced EIA expanded poleward and westward from just below 20° magnetic latitude (MLAT) to beyond 30° MLAT at sunrise. The chief ramification of the enhanced EIA was strong GPS scintillation which was observed poleward of 30° northern MLAT and lasted until 8:00 local time. In total, the amplitude scintillation and phase fluctuations lasted for ∼5 h at latitudes north of 20°MLAT in central America.

中文翻译：

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极低纬度总电子含量增强和全球定位系统黎明闪烁

我们报告了黎明时极端电离层等离子体密度增强和全球定位系统 (GPS) 闪烁，在扩大的赤道电离异常 (EIA) 中观察到。中美洲的总电子含量（TEC）在日出时达到 50 TECu，几乎是正常下午峰值的两倍。增强的 EIA 向极地和向西扩展，从略低于 20° 磁纬度 (MLAT) 到日出时超过 30° MLAT。增强型 EIA 的主要后果是强烈的 GPS 闪烁，在 MLAT 以北 30°的极地观测到并持续到当地时间 8:00。总的来说，在中美洲 20°MLAT 以北的纬度上，振幅闪烁和相位波动持续了约 5 小时。