@Article{FagundesBAMMSAPSAPA:2012:AtNiSp,
author = "Fagundes, P. R. and Bittencourt, J. A. and Abreu, A. J. and Moor,
Lilian and Muella, M. T. A. H. and Sahai, Y. and Abalde, Jos{\'e}
Ricardo and Pezzopane, M. and Sobral, Jose Humberto Andrade and
Abdu, M. A. and Pimenta, Alexandre Alvares and Amorim, D. C. M.",
affiliation = "Univ Vale Paraiba, BR-12244000 Sao Jose Dos Campos and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and Univ Vale Paraiba,
BR-12244000 Sao Jose Dos Campos and Univ Vale Paraiba, BR-12244000
Sao Jose Dos Campos and Univ Vale Paraiba, BR-12244000 Sao Jose
Dos Campos and Univ Vale Paraiba, BR-12244000 Sao Jose Dos Campos
and Univ Vale Paraiba, BR-12244000 Sao Jose Dos Campos and Ist
Nazl Geofis \& Vulcanol, I-00143 Rome, Italy and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais
(INPE)}",
title = "Atypical nighttime spread-F structure observed near the southern
crest of the ionospheric equatorial ionization anomaly",
journal = "Journal of Geophysical Research",
year = "2012",
volume = "117",
number = "A04308",
pages = "9--18",
month = "Apr.",
keywords = "F-region, Ionosphere, irregularities, plasma, thermospheric,
region plasma depletions, additional layer, zonal velocities,
fortaleza, bubbles, Brazil, solar, generation, ionograms,
f3-layer.",
abstract = "An atypical nighttime spread-F structure is observed on ionograms
at or above the F-2 trace, near the crest of the ionospheric
equatorial ionization anomaly (EIA) region. This ionospheric
atypical spread-F phenomenon was observed using two closed spaced
(similar to 115 km) ionospheric soundings stations located in Sao
Jose dos Campos (23.21 degrees S, 45.97 degrees W) and Cachoeira
Paulista (22.70 degrees S, 45.01 degrees W), Brazil, in a
low-latitude station (near the southern crest of the EIA region),
during nighttime, low solar activity, and quiet geomagnetic
conditions. This structure, in the initial phase, appears in the
ionogram as a faint spread-F trace above or at the F-2-layer peak
height. After a few minutes, it develops into a strong spread-F
trace, and afterwards, it moves to altitudes below the F-2-layer
peak heights. Finally, the atypical nighttime F-layer trace
structure may remain for a while between the F-layer bottom side
and peak height or can move to an altitude above the F-layer peak
height, and then it disappears. In order to have a comprehensive
view of the ionospheric environment characterizing the phenomenon
under study, complementary data from six GPS station were used to
investigate the ionosphere environment conditions, during both
events. The six GPS stations used in this study are distributed
from near the equatorial region to low latitudes and provide
evidence that the atypical nighttime spread-F structures are not
related with large scale equatorial irregularities (plasma
bubbles).",
doi = "10.1029/2011JA017118",
url = "http://dx.doi.org/10.1029/2011JA017118",
issn = "0148-0227",
label = "lattes: 0665861578886219 11 FagundesBAMSASAPA:2012:AtNiSp",
language = "en",
targetfile = "2011JA017118.pdf",
urlaccessdate = "13 maio 2024"
}