Recent work has demonstrated that global Pc5 pulsations observed by ground‐based magnetometers may be accompanied by periodic oscillations in the total electron content (TEC) of the ionosphere measured by GPS receivers. These TEC observations may provide new insights into magnetosphere‐ionosphere coupling mechanisms, especially when combined with other ground‐based observational techniques. Presented in this paper is a large‐scale morning sector Pc5 event which was observed simultaneously by ground‐based magnetometers, two high‐frequency Super Dual Auroral Radar Network (SuperDARN) radars, and several Global Positioning System (GPS)/TEC receivers. The transient 2.6 mHz pulsations observed by the ground magnetometers and radars are accompanied by periodic fluctuations in the time rate‐of‐change of TEC (ROT) at the same frequency. To investigate possible mechanisms for the TEC modulation by ultralow frequency (ULF) waves, we determine the ratios between the spectral amplitudes of the magnetic, ionospheric Doppler velocity and ROT oscillations. The relationship between the simultaneous magnetic field and ionospheric Doppler velocity oscillations can be reasonably well interpreted using the theory of Alfven wave interaction with the thin ionospheric layer. Though the observed ratio between ROT and Doppler velocity amplitudes can be explained by the occurrence of local steep gradient of the topside ionosphere plasma at auroral latitudes, the responsible modulation mechanism cannot be considered as firmly established.

中文翻译：

---

SuperDARN雷达和GPS / TEC技术同时观测到的ULF波对电离层的周期性调制

最近的工作表明，地面磁力计观测到的全球Pc5脉动可能伴有GPS接收机测得的电离层总电子含量（TEC）的周期性振荡。这些TEC观测可能会提供有关磁层-电离层耦合机制的新见解，尤其是与其他地面观测技术结合使用时。本文介绍的是一次大型的早晨Pc5事件，该事件同时由地面磁力计，两个高频超双极光雷达网络（SuperDARN）雷达和几个全球定位系统（GPS）/ TEC接收器同时观测到。地面磁力仪和雷达观测到的2.6 mHz瞬态脉冲伴随着TEC（ROT）在相同频率下的时间变化率的周期性波动。为了研究通过超低频（ULF）波进行TEC调制的可能机制，我们确定了磁，电离层多普勒速度的频谱幅度与ROT振荡之间的比率。利用Alfven波与薄电离层的相互作用理论，可以合理地很好地解释同时磁场与电离层多普勒速度振荡之间的关系。尽管观测到的ROT和多普勒速度振幅之比可以通过极光纬度上层电离层等离子体的局部陡梯度的出现来解释，但不能认为可靠的调制机制已经建立。电离层多普勒速度和ROT振荡。利用Alfven波与薄电离层的相互作用理论，可以合理地很好地解释同时磁场与电离层多普勒速度振荡之间的关系。尽管观测到的ROT和多普勒速度振幅之比可以通过极光纬度上层电离层等离子体的局部陡梯度的出现来解释，但不能认为可靠的调制机制已经建立。电离层多普勒速度和ROT振荡。利用Alfven波与薄电离层的相互作用理论，可以合理地很好地解释同时磁场与电离层多普勒速度振荡之间的关系。尽管观测到的ROT和多普勒速度振幅之间的比率可以通过极光纬度上层电离层等离子体局部陡峭梯度的出现来解释，但不能认为可靠的调制机制已经确立。