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Abstract This work investigates mid‐ and low‐latitude ionospheric disturbances over the American sector during a moderate but geo‐effective geomagnetic storm on 13–14 March 2022 (π‐Day storm), using ground‐based Global Navigation Satellite System total electron content data, ionosonde observations, and space‐borne measurements from the Global‐scale Observations of Limb and Disk (GOLD), Swarm, the Defense Meteorological Satellite Program (DMSP), and the Ionospheric Connection Explorer (ICON) satellites. Our results show that this modest but geo‐effective storm created a number of large ionospheric disturbances, especially the dynamic multi‐scale electron density gradient features in the storm main phase as follows: (a) The low‐latitude equatorial ionization anomaly (EIA) exhibited a dramatic storm‐time deformation and reformation, where the EIA crests evolved into a bright equatorial band for 1–2 hr and then quickly separated back into the typical double‐crest structure with a broad crest width and deep equatorial trough. (b) Strong equatorial plasma bubbles (EPBs) occurred with an abnormally high latitude/altitude extension, reaching the geomagnetic latitude of ∼30°, corresponding to an Apex height of 2,600 km above the dip equator. (c) The midlatitude ionosphere experienced a conspicuous storm‐enhanced density (SED) plume structure associated with the subauroral polarization stream (SAPS). This SED/SAPS feature showed an unusual temporal variation that intensified and diminished twice. These distinct mid‐ and low‐latitude ionospheric disturbances could be attributed to the storm‐time electrodynamic effect of electric field perturbation, along with contributions from neutral dynamics and thermospheric composition change.
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The 2022 Starlink Geomagnetic Storms: Global Thermospheric Response to a High‐Latitude Ionospheric Driver
Abstract In this study, we present ionospheric observations of field‐aligned currents from AMPERE and the ESA Swarm A satellite, in conjunction with high‐resolution thermospheric density measurements from accelerometers on board Swarm C and GRACE‐FO, for the third and 4 February 2022 geomagnetic storms that led to the loss of 38 Starlink internet satellites. We study the global storm time response of the thermospheric density enhancements, including their decay and latitudinal distribution. We find that the thermospheric density enhances globally in response to high‐latitude energy input from the magnetosphere‐solar wind system and takes at least a full day to recover to pre‐storm density levels. We also find that the greatest density perturbations occur at polar latitudes consistent with the magnetosphere‐ionosphere dayside cusp, and that there appeared to be a saturation of the thermospheric density during the geomagnetic storm on the fourth. Our results highlight the critical importance of high‐latitude ionospheric observations when diagnosing potentially hazardous conditions for low‐Earth‐orbit satellites.
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- Award ID(s):
- 2002574
- PAR ID:
- 10532371
- Publisher / Repository:
- Space Weather
- Date Published:
- Journal Name:
- Space Weather
- Volume:
- 22
- Issue:
- 2
- ISSN:
- 1542-7390
- 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/10.1029/2023SW003748
