Response of Neutral Temperature in the Lower Thermosphere to Geomagnetic Storms Observed by ICON/MIGHTI
Abstract This study utilizes ICON/MIGHTI observations and reveals, for the first time, the response of neutral temperature in the lower thermosphere (∼110–130 km) to minor‐to‐moderate geomagnetic disturbances. A case study of the 12 October 2021 storm reveals surprising storm‐time temperature enhancements across all observed latitudes (∼14°–42°N), with a peak enhancement of 28% at 130 km near 42°N. The average enhancement within 35°–40°N reaches 18% at 130 km. Statistical analysis indicates a positive correlation between temperature enhancement and geomagnetic activity intensity. The increase rates with respect to ap index are larger in 35°–40°N than those in 20°–25°N. The increase rates increase with altitude, reaching 0.168%/nT at 130 km over 35°–40°N. The peaks of temperature enhancements lag the ap/Dst index maxima/minima for most storms. Comparisons with the NRLMSIS2.1 empirical model and the physics‐based TIEGCM‐ICON model show that both models capture storm‐time temperature enhancements but underestimate their magnitudes compared to observations.
Authors
- Jiyao Xu (ORCID: https://orcid.org/0000-0003-2868-0055)
- Xiao Liu (ORCID: https://orcid.org/0000-0002-9163-0280)
- Juliano Moro (ORCID: https://orcid.org/0000-0003-4078-2222)
- Maosheng He (ORCID: https://orcid.org/0000-0001-6112-2499)
- Wenbin Wang (ORCID: https://orcid.org/0000-0002-6287-4542)
- Yajun Zhu (ORCID: https://orcid.org/0009-0001-0648-1373)
- Weijun Liu (ORCID: https://orcid.org/0000-0002-0523-9753)
- Hong Gao (ORCID: https://orcid.org/0000-0002-5271-1117)
Institutions
- NSF National Center for Atmospheric Research (US)
- NSF NCAR High Altitude Observatory (US)
- Chinese Academy of Sciences (CN)
- National Space Science Center (CN)
- Henan Normal University (CN)
- Instituto Nacional de Pesquisas Espaciais (BR)
Publication Details
- Journal
- Geophysical Research Letters
- Published
- 2025-08-31
- DOI
- https://doi.org/10.1029/2025gl116133
- Citations
- 1
- Primary Topic
- Ionosphere and magnetosphere dynamics
- Type
- article
- Field-Weighted Citation Impact
- 1.15
Funders
- National Natural Science Foundation of China
- Chinese Academy of Sciences