Artículo

F3 layer observations at low and equatorial latitudes in Brazil

Batista, I. S.; Balan, N.; Abdu, M. A.; Macdougall, J.; Barbosa Neto, P. F.

Instituto de Geofísica, UNAM, publicado en Geofísica Internacional, y cosechado de Revistas UNAM

Licencia de uso

Procedencia del contenido

Entidad o dependencia
Instituto de Geofísica, UNAM
Revista
Repositorio
Contacto
Revistas UNAM. Dirección General de Publicaciones y Fomento Editorial, UNAM en revistas@unam.mx

Cita

Batista, I. S., et al. (2000). F3 layer observations at low and equatorial latitudes in Brazil. Geofísica Internacional; Vol. 39 No. 1, 2000. Recuperado de https://repositorio.unam.mx/contenidos/42388

Descripción del recurso

Autor(es)
Batista, I. S.; Balan, N.; Abdu, M. A.; Macdougall, J.; Barbosa Neto, P. F.
Tipo
Artículo de Investigación
Área del conocimiento
Físico Matemáticas y Ciencias de la Tierra
Título
F3 layer observations at low and equatorial latitudes in Brazil
Fecha
2012-05-01
Resumen
Recent studies using model calculation and ionospheric observations have revealed the existence of an additional layer in the topside equatorial ionosphere, the F3 layer. In this work we analyze ionosonde data from two low/equatorial latitude stations in Brazil, during the year 1995, a low solar activity period, in order to study the F3 layer at those locations. At the magnetic station São Luís (2.3° S, 44° W, dip angle -0.5°) the occurrence of the F3 layer is much less evident than at the low latitude station Fortaleza (4° S, 38° W, dip angle -9°). The ionograms recorded at Fortaleza in 1995 show the existence of the layer on 50% of the days, with the occurrence being more frequent (75%) and distinct in summer. The layer appears on 66% of the days in winter and 28% in equinoxes. The layer starts to appear around 0930 LT and lasts from a few minutes to several hours. Its mean height varies from 570 km in summer to 440 km in winter, although on a day to day basis it can vary from as low as 375 km to 775 km. The ionospheric model SUPIM (Sheffield University Plasmasphere-Ionosphere Model) explains well the occurrence of the layer in summer, but not in winter, unless some key input parameters, such as electric field and winds are modified. This suggests that the existing models for electric fields and winds are not representative for the Brazilian low latitude region during winter.
Tema
Ionosphere; F3 Layer; low latitudes.; Ionosfera; capa F3; baja latitud.
Idioma
spa
ISSN
0016-7169

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