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Abstract An annular solar eclipse was visible on 14 October 2023 from 15:00–21:00 UT as its path traveled across North, Central, and South America. In this letter, we present the first multi‐frequency Super Dual Auroral Radar Network (SuperDARN) observations of the bottomside ionospheric response to a solar eclipse using a novel experimental mode designed for the October 2023 annular eclipse. We compare our results from the mid‐latitude Christmas Valley East radar with measurements of the vertical electron density profile from the nearby Boulder Digisonde, finding the changes in 1‐ and 2‐hop ground scatter skip distance are well correlated with the ‐layer density response, which lags the peak obscuration by 30 min. Changes in the line‐of‐sight Doppler shifts are better aligned with the time derivative of eclipse obscuration.
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HF Radar Observations and Modeling of the Impact of the 8 April 2024 Total Solar Eclipse on the Ionosphere‐Thermosphere System
Abstract 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 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.
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- PAR ID:
- 10559842
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 51
- Issue:
- 24
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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