We present a comparison of the ionosphere and plasmasphere total electron content over nearly geomagnetic conjugate locations Pruhonice ($50.0°$N, $14.6°$E; $45.7°$N geomagnetic), Czech Republic and Hermanus ($34.4°$S, $19.2°$E; $42.3°$S geomagnetic), South Africa during the low solar activity period of 2009–2010. The bottomside ionosphere, topside ionosphere and plasmaspheric contributions to the total electron content (TEC) derived from the Global Positioning System (GPS) observations are separately estimated from ionosonde and Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) radio occultation data. Over the ionosonde location, COSMIC electron density (Ne) profiles are considered when the maximum height of the F2 layer (hmF2) lies within spatial resolutions of $4.5°\times 4.5°$ in latitudes/longitudes, and the Ne profile does not exceed $10°$. For the first time, we have statistically quantified the topside ionosphere contribution to GPS TEC based on radio occultation data and revealed that it accounts for about 50% of the TEC during low solar activity periods. Finally, we have demonstrated that the determination of electron content contribution at different altitudes is important for understanding ionospheric storm mechanisms during space weather events especially geomagnetic storms.

我们比较了近地磁共轭位置 Pruhonice ($50.0°$否， $14.6°$乙; $45.7°$N地磁），捷克共和国和赫曼努斯（$34.4°$， $19.2°$乙; $42.3°$S 地磁），南非在 2009-2010 年的低太阳活动期。从全球定位系统 (GPS) 观测得出的底部电离层、顶部电离层和等离子体层对总电子含量 (TEC) 的贡献分别从电离层和气象、电离层和气候星座观测系统 (COSMIC) 无线电掩星数据中估算。在离子探空仪位置上，当 F2 层的最大高度 (hmF2) 位于空间分辨率为$4.5°\times 4.5°$ 在纬度/经度，并且 Ne 剖面不超过 $10°$. 我们第一次根据无线电掩星数据统计量化了上部电离层对 GPS TEC 的贡献，并表明它在太阳活动低的时期约占 TEC 的 50%。最后，我们已经证明，确定不同高度的电子含量贡献对于理解空间天气事件尤其是地磁风暴期间的电离层风暴机制很重要。