Positive and negative GPS-TEC ionospheric storm effects during the extreme space weather event of March 2015 over the Brazilian sector

Autor(es)

Fagundes, P. R. ; Cardoso, F. A. ; Fejer, B. G. ; Venkatesh, K. ; Ribeiro, B. A. G. ; Pillat, V. G.

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS; v. 121, n. 6, p. 5613-5625, JUN 2016.
• Citações Web of Science: 20

Resumo

We studied the response of the ionosphere (F region) in the Brazilian sector during extreme space weather event of 17 March 2015 using a large network of 102 GPS-total electron content (TEC) stations. It is observed that the vertical total electron content (VTEC) was severely disturbed during the storm main and recovery phases. A wavelike oscillation with three peaks was observed in the TEC diurnal variation from equator to low latitudes during the storm main phase on 17-18 March 2015. The latitudinal extent of the wavelike oscillation peaks decreased from the beginning of the main phase toward the recovery phase. The first peak extended from beyond 0 degrees S to 30 degrees S, the second occurred from 6 degrees S to 25 degrees S, whereas the third diurnal peaks was confined from 13 degrees S to 25 degrees S. In addition, a strong negative phase in VTEC variations was observed during the recovery phase on 18-19 March 2015. This ionospheric negative phase was stronger at low latitudes than in the equatorial region. Also, two latitudinal chains of GPS-TEC stations from equatorial region to low latitudes in the east and west Brazilian sectors are used to investigate the storm time behavior of the equatorial ionization anomaly (EIA) in the east and west Brazilian sectors. We observed an anomalous behavior in EIA caused by the wavelike oscillations during the storm main phase on 17 March, and suppression of the EIA, resulting from the negative phase in VTEC, in the storm recovery phase. (AU)

• Processo FAPESP: 12/08445-9 - Estudo da variabilidade dia-a-dia da mesosfera, termosfera e ionosfera em baixas latitudes e região equatorial, durante o ciclo solar 24
• Beneficiário: Paulo Roberto Fagundes
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/17380-0 - Estudo da ionosfera em baixas latitudes usando ionossondas e GPS.
• Beneficiário: Kavutarapu Venkatesh
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado