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On 10 May 2024, a series of coronal mass ejections were detected at Earth followed by one of the most powerful geomagnetic storms since November 2003. Leveraging a multi–technique approach, this paper provides an account of the ground geomagnetic response during the 10–11 May 2024 extreme geomagnetic storm. More specifically, we show that at the mid-latitudes in the American sector, the storm produced extreme ground geomagnetic field perturbations between 01:50 UT and 02:30 UT on 11 May. Then using the Spherical Elementary Current System method, it is shown that the perturbations were associated with an intense westward propagating auroral westward electrojet current. Finally, with the aid of auroral all-sky images from the Missouri Skies Observatory, we demonstrate that an intense isolated substorm event with onset located between the Great Lakes region and the East Coast United States was the main source of the extreme westward electrojet current and the geomagnetic field perturbations at these typical mid-latitude locations. This study emphasizes the increased risk associated with expansion of the auroral oval into the mid-latitudes during extreme geomagnetic activity.
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Imaging the May 2024 Extreme Aurora With Ionospheric Total Electron Content
The continental United States is well instrumented with facilities for mid‐latitude upper atmosphere research that operate on a continuous basis. In addition, citizen scientists provide a wealth of information when unusual events occur. We combine ionospheric total electron content (TEC) data from distributed arrays of GNSS receivers, magnetometer chains, and auroral observations obtained by citizen scientists, to provide a detailed view of the intense auroral breakup and westward surge occurring at the peak of the 10–11 May 2024 extreme geomagnetic storm. Over a 20‐min interval, vertical TEC (vTEC) increased at unusually low latitude (∼45°) and rapidly expanded azimuthally across the continent. Individual receiver/satellite data sets indicate sharp bursts of greatly elevated of vTEC (∼50 TECu). Intense red aurora was co‐located with the leading edge of the equatorward and westward TEC enhancements, indicating that the large TEC enhancement was created by extremely intense low‐energy precipitation during the rapid substorm breakup.
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- PAR ID:
- 10573358
- Editor(s):
- Yau, Andrew
- Publisher / Repository:
- Geophysical Research Letters
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 51
- Issue:
- 20
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1029/2024GL111981
