The path of totality of the 8 April 2024 solar eclipse traversed the fields-of-view of four US SuperDARN radars. This rare scenario provided an excellent opportunity to monitor the large-scale ionospheric response to the eclipse. In this study, we present observations made by the Blackstone (BKS) SuperDARN radar and a Digisonde during the eclipse. Two striking effects were observed by the BKS radar: (a) the Doppler velocities associated with ground scatter coalesced into a pattern clearly organized by the line of totality, with a reversal in sign across this line, and, (b) a delay of $\sim$45 min between time of maximum obscuration and maximum effect on the skip distance. The skip distance estimated using a SAMI3 simulation of the eclipse did not however capture the asymmetric time-delay. These observations suggest that the neutral atmosphere plays an important role in controlling ionospheric plasma dynamics, which were missing in SAMI3 simulations.

中文翻译：

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HF 雷达观测和 2024 年 4 月 8 日日全食对电离层-热层系统的影响建模


2024 年 4 月 8 日日食的全食路径穿越了四台美国 SuperDARN 雷达的视野。这种罕见的情况为监测大规模电离层对日食的响应提供了绝佳的机会。在这项研究中，我们展示了 Blackstone （BKS） SuperDARN 雷达和数码探空仪在日食期间的观测结果。BKS 雷达观察到两个引人注目的效果：（a） 与地面散射相关的多普勒速度合并成一个由整体线清晰组织的模式，这条线上的符号反转，以及 （b） 最大遮蔽时间和对跳跃距离的最大影响之间延迟 $\sim$ 45 分钟。然而，使用 SAMI3 日食模拟估计的跳跃距离并没有捕捉到不对称的时间延迟。这些观测结果表明，中性大气在控制电离层等离子体动力学方面起着重要作用，而这在 SAMI3 模拟中是缺失的。