Abstract. The ionospheric Total Electron Content (TEC) provided by the International GNSS Service (IGS), and the Coupled Thermosphere Ionosphere Plasmasphere Electrodynamics (CTIPe) model simulated TEC have been used to investigate the delayed ionospheric response against solar flux and its trend during the years 2011 to 2013. The analysis of the distinct low and mid-latitudes TEC response over 15° E shows a better correlation of observed TEC and the solar radio flux index F10.7 in the Southern Hemisphere compared to the Northern Hemisphere. Thus, a significant hemispheric asymmetry is observed. The ionospheric delay estimated using model simulated TEC is in good agreement with the delay estimated for observed TEC against Solar Dynamics Observatory (SDO) EUV Variability Experiment (EVE) measured flux. The average delay for the observed (modeled) TEC is 17(16) h. The average delay calculated for observed and modeled TEC is 1 and 2 h longer in the Southern Hemisphere compared to the Northern Hemisphere. Furthermore, the observed TEC is compared with the modeled TEC simulated using the SOLAR2000 and EUVAC flux models within CTIPe over Northern and Southern Hemispheric grid points. The analysis suggests that TEC simulated using the SOLAR2000 flux model overestimates the observed TEC, which is not the case when using the EUVAC flux model.

中文翻译：

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电离层对太阳EUV辐射变化的响应：基于CTIPe模型模拟和卫星测量的比较

摘要。国际GNSS服务（IGS）提供的电离层总电子含量（TEC）和耦合热层电离层等离子体电动力学（CTIPe）模型模拟​​的TEC已用于研究2011年电离层对太阳通量的延迟响应及其趋势到2013年。对北纬15°E以内的中低纬度TEC响应的分析表明，与北半球相比，南半球观测到的TEC与太阳辐射通量指数F10.7具有更好的相关性。因此，观察到明显的半球不对称性。使用模拟TEC模型估算的电离层延迟与针对太阳动力学天文台（SDO）EUV变异性实验（EVE）测得的通量为观测TEC估算的延迟非常吻合。观察到的（建模的）TEC的平均延迟为17（16）h。与北半球相比，南半球为观测和模拟的TEC计算的平均延迟分别长1和2小时。此外，将观测到的TEC与在北半球和南半球网格点上CTIPe中使用SOLAR2000和EUVAC通量模型模拟的建模TEC进行了比较。分析表明，使用SOLAR2000磁通量模型模拟的TEC高估了观察到的TEC，而使用EUVAC磁通量模型则不是这种情况。将观测到的TEC与在北半球和南半球网格点CTIPe中使用SOLAR2000和EUVAC通量模型模拟的建模TEC进行比较。分析表明，使用SOLAR2000磁通量模型模拟的TEC高估了观察到的TEC，而使用EUVAC磁通量模型则不是这种情况。将观测到的TEC与在北半球和南半球网格点CTIPe中使用SOLAR2000和EUVAC通量模型模拟的建模TEC进行比较。分析表明，使用SOLAR2000磁通量模型模拟的TEC高估了观察到的TEC，而使用EUVAC磁通量模型则不是这种情况。