This paper focuses on the validation of the latest version of the International Reference Ionosphere (IRI-2016) model in predicting the vertical total electron content (VTEC) variation over Ethiopian ionospheric region during a high solar activity (2012-2016) phase. The diurnal, monthly and seasonal VTEC variations were analyzed from dual-frequency global positioning system (GPS) and IRI-2016 model at the Debark station. The diurnal, monthly and seasonal maximum TEC values measured between around 9:00 and 18:00 UT (12:00 and 21:00 LT) hours and the minimum TEC values measured before 9:00 (12:00 LT) and after 18:00 UT (21:00 LT). The overall results show that IRI-2016 model generally overestimates the diurnal, monthly and seasonal mean VTEC values during the high solar activity (2012-2016) phase. The model prediction generally follows that the monthly and seasonal variations of the measured VTEC values in equinoctial months are higher than solstice months. The monthly mean and seasonal mean values of IRI-TEC and GPS-TEC mostly correlates before early morning and after evening hours and also slightly IRI-TEC underestimates starting from morning hours up to evening hours. The magnetic storm effects on GPS-TEC are associated with fluctuations. However, the IRI-TEC values show smooth pattern during both in storm on and off options. Consequently, the IRI-2016 model does not correctly respond to the effects of the resulting storm disturbance.

中文翻译：

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在埃塞俄比亚电离层上测试和验证 IRI-2016 模型

本文侧重于验证最新版本的国际参考电离层 (IRI-2016) 模型，以预测高太阳活动 (2012-2016) 阶段埃塞俄比亚电离层区域的垂直总电子含量 (VTEC) 变化。从Debark站的双频全球定位系统（GPS）和IRI-2016模型分析了昼夜、月和季节的VTEC变化。在 9:00 和 18:00 UT（12:00 和 21:00 LT）之间测量的昼夜、每月和季节性最大 TEC 值以及在 9:00（12:00 LT）之前和 18 点之后测量的最小 TEC 值:00 UT（21:00 LT）。总体结果表明，IRI-2016 模型普遍高估了高太阳活动（2012-2016）阶段的日、月和季节平均 VTEC 值。模型预测通常遵循在春分月测量的 VTEC 值的月度和季节变化高于冬至月。IRI-TEC 和 GPS-TEC 的月平均值和季节平均值大多与清晨之前和傍晚之后相关，并且 IRI-TEC 从早上到晚上的时间也略有低估。GPS-TEC 上的磁暴效应与波动有关。然而，IRI-TEC 值在风暴开启和关闭选项期间均显示平滑模式。因此，IRI-2016 模型无法正确响应由此产生的风暴干扰的影响。IRI-TEC 和 GPS-TEC 的月平均值和季节平均值大多与清晨之前和傍晚之后相关，并且 IRI-TEC 从早上到晚上的时间也略有低估。GPS-TEC 上的磁暴效应与波动有关。然而，IRI-TEC 值在风暴开启和关闭选项期间均显示平滑模式。因此，IRI-2016 模型无法正确响应由此产生的风暴干扰的影响。IRI-TEC 和 GPS-TEC 的月平均值和季节平均值大多与清晨之前和傍晚之后相关，并且 IRI-TEC 从早上到晚上的时间也略有低估。GPS-TEC 上的磁暴效应与波动有关。然而，IRI-TEC 值在风暴开启和关闭选项期间均显示平滑模式。因此，IRI-2016 模型无法正确响应由此产生的风暴干扰的影响。