Seasonal and solar activity variations of F-3 layer and quadruple stratification (StF-4) near the equatorial region

Autor(es)

Tardelli, A. ; Fagundes, P. R. ; Pezzopane, M. ; Venkatesh, K. ; Pillat, V. G.

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS; v. 121, n. 12, p. 12116-12125, DEC 2016.
• Citações Web of Science: 5

Resumo

The study of multiple stratification of the F layer has the initial records in the midtwentieth century. Since then, many studies were focused on F-3 layer. The diurnal, seasonal, and solar activity variations of the F-3 layer characteristics have been investigated by several researchers. Recently, investigations on multiple stratifications of F layer received an important boost after the quadruple stratification (StF-4) was observed at Palmas (10.3 degrees S, 48.3 degrees W; dip latitude 6.6 degrees S-near-equatorial region), Brazil. The present study reports the latest findings related with the seasonal and solar activity characteristics of the F-3 layer and StF-4 near the equatorial region during the period from 2002 to 2006. A significant connection between StF-4 and F-3 layer has been noticed, since the StF-4 is always preceded and followed by a F-3 layer appearance. However, the F-3 layer and the StF-4 present different seasonal and solar cycle variations. At a near-equatorial station Palmas, the F-3 layer shows the maximum and minimum occurrences during summer and winter seasons, respectively. On the contrary, the StF-4 presents the maximum and minimum occurrences during winter and summer seasons, respectively. While the F-3 layer occurrence is not affected by solar cycle, the StF-4 appearance is instead more frequent during high solar activity. (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: 15/24791-2 - Estudo de multiplas estratificações da camada-f em baixas latitudes e região equatorial
• Beneficiário: Alexandre Tardelli
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• 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