| Full text | |
| Author(s): Show less - |
Souza, J. R.
;
Dandenault, P.
;
Santos, A. M.
;
Riccobono, J.
;
Migliozzi, M. A.
;
Kapali, S.
;
Kerr, R. B.
;
Mesquita, R.
;
Batista, I. S.
;
Wu, Q.
;
Pimenta, A. A.
;
Noto, J.
;
Huba, J.
;
Peres, L.
;
Silva, R.
;
Wrasse, C.
Total Authors: 16
|
| Document type: | Journal article |
| Source: | JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS; v. 129, n. 7, p. 16-pg., 2024-07-01. |
| Abstract | |
The paper presents the effects of the storm-time prompt penetration electric fields (PPEF) and traveling atmospheric disturbances (TADs) on the total electron content (TEC), foF2 and hmF2 in the American sector (north and south) during the geomagnetic storm on 23-24 April 2023. The data show a poleward shift of the Equatorial Ionization Anomaly (EIA) crests to 18 degrees N and 20 degrees S in the evening of 23 April (attributed to eastward PPEF) and the EIA crests remaining almost in the same latitudes after the PPEF reversed westward. The thermospheric neutral wind velocity, foF2, hmF2, and TEC variations show that TADs from the northern and southern high latitudes propagating equatorward and crossing the equator after midnight on 23 April. The meridional keograms of Delta TEC show the TAD structures in the north/south propagated with phase velocity 470/485 m/s, wave length 4,095/4,016 km and period 2.42/2.30 hr, respectively. The interactions of the TADs also appear to modify the wind velocities in low latitudes. The eastward PPEF and equatorward TADs also favored the development of a clear/not so clear F3 layer in northern/southern regions of the equator. The thermosphere-ionosphere-magnetosphere system is largely affected during events of geomagnetic storms. Its dynamics, mainly in the ionized environment, may impact modern lives by degradations in the satellite signals affecting, for example, all applications involving Global Navigation Satellite System. The thermosphere and ionosphere responses to the large geomagnetic storm of 23-24 April 2023 are analyzed here and the main discoveries are the unexpected spatial plasma density distribution over Boa Vista (MLat approximate to 8 degrees N) due to resulting effects of a disturbed eastward electric field and traveling atmospheric disturbance (TAD). The interactions/interferences of TADs were able to explain the unexpected moment of the peak in thermospheric neutral wind speed measurements over the equatorial station, as well as all variations in ionospheric parameters (foF2, hmF2, and total electron content) recorded in pairs by seven Digisondes and GNSS receivers spread across Brazil. Interactions of traveling atmospheric disturbances (TADs) cause unexpected thermospheric neutral wind speeds in the American equatorial and low-latitude sectors The effects resulting from a disturbed electric field and TADs were able to produce anomalous electron density distribution at low latitudes The variations in the ionospheric observational measurements recorded around 4 UT in Brazil on 24 April 2023 were explained by the passages of TADs (AU) | |
| FAPESP's process: | 17/50115-0 - GNSS technology for supporting air navigation |
| Grantee: | Joao Francisco Galera Monico |
| Support Opportunities: | Research Grants - Research in Public Policies |