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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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This content will become publicly available on May 1, 2026
Atmospheric and Insect Responses to a Total Solar Eclipse
Abstract How do the atmosphere and airborne insects respond to the abrupt cessation and restoration of sunlight during a total eclipse? The Flexible Array of Radars and Mesonets (FARM), including three mobile Doppler on Wheels (DOW) radars, mobile mesonets, Pod weather stations, and an upper-air sounding system, was deployed as an unprecedentedly dense observing network in the path of totality of the 21 August 2017 eclipse that spanned the United States from its Pacific to Atlantic coasts. This was the first targeted dual-polarization radar, multiple-Doppler, and micronet study of the impacts of totality on meteorology and insect behavior. The study area was chosen to be completely sunny, nearly devoid of trees, with homogeneous, nonforested land use, and very flat. This resulted in as near an ideal observational environment as realistically attainable to observe the effects of a total solar eclipse absent the confounding effects of variable cloud shading, terrain, and land use. Rapid and substantial changes in the boundary layer and propagation of a prominent radar fine line associated with a posttotality wind shift mechanism different than previously hypothesized were observed. Profound and rapid changes in airborne insect behavior were documented, including descent and then reascent during the minutes immediately surrounding totality, with implications related to solar-related insect navigational mechanisms and behavior.
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- Award ID(s):
- 2113207
- PAR ID:
- 10646100
- Publisher / Repository:
- American Meteorological Society
- Date Published:
- Journal Name:
- Bulletin of the American Meteorological Society
- Volume:
- 106
- Issue:
- 5
- ISSN:
- 0003-0007
- Page Range / eLocation ID:
- E809 to E828
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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