We show the statistical characteristics of quasi-6-day wave (Q6DW) absolute amplitude in f oE and f oF 2 during 2014–2015 by using six ionosondes at different latitudes. The results show that f oE perturbations maximized at mid-latitudes during equinoxes, and the maximum amplitude of Q6DW in f oF 2 occurred near the northern crest of equatorial ionospheric anomaly (EIA). In addition, the absolute amplitude of Q6DW in f oF 2 increased with increasing solar activity. Our observations suggest that the dissipative Q6DW-like oscillations in the lower thermosphere may cause variations in the thermospheric neutral density via mixing effect and further result in f oE disturbances in Q6DW events. Furthermore, the E region wind dynamo could also be modulated by the 6-day wave, thus leading to the disturbances in vertical plasma velocity via E × B drifts and F region electron density. Our observational investigation provides evidence of thermosphere–ionosphere coupling in the mid- and low-latitude region.

中文翻译：

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2014-2015年近期太阳活动极大期电离层E区和F区的准6天波效应

我们通过使用不同纬度的六个电离探测器显示了 2014-2015 年期间 f oE 和 f oF 2 准 6 天波 (Q6DW) 绝对振幅的统计特征。结果表明，在春分点期间，f oE 扰动在中纬度地区最大，而 f oF 2 中 Q6DW 的最大振幅发生在赤道电离层异常 (EIA) 北峰附近。此外，Q6DW 在 f oF 2 中的绝对振幅随着太阳活动的增加而增加。我们的观察表明，较低热层中的耗散性 Q6DW 类振荡可能会通过混合效应导致热层中性密度的变化，并进一步导致 Q6DW 事件中的 f oE 扰动。此外，E 区风力发电机也可以被 6 天波调制，因此通过 E × B 漂移和 F 区电子密度导致垂直等离子体速度的扰动。我们的观测调查提供了中低纬度地区热层-电离层耦合的证据。