@Article{AbreuFagSahJesBit:2010:HeAsIo,
author = "Abreu, Alessandro Jos{\'e} de and Fagundes, P. R. and Sahai, Y.
and Jesus, R. de and Bittencourt, J. A.",
affiliation = "Fisica e Astronomia, Universidade do Vale do Para{\'{\i}}ba
(UNIVAP), S{\~a}o Jos{\'e} dos Campos, Brazil and Fisica e
Astronomia, Universidade do Vale do Para{\'{\i}}ba (UNIVAP),
S{\~a}o Jos{\'e} dos Campos, Brazil and Fisica e Astronomia,
Universidade do Vale do Para{\'{\i}}ba (UNIVAP), S{\~a}o
Jos{\'e} dos Campos, Brazil and Fisica e Astronomia, Universidade
do Vale do Para{\'{\i}}ba (UNIVAP), S{\~a}o Jos{\'e} dos
Campos, Brazil and {Instituto Nacional de Pesquisas Espaciais
(INPE)}",
title = "Hemispheric asymmetries in the ionospheric response observed in
the American sector during an intense geomagnetic storm",
journal = "Journal of Applied Geophysics",
year = "2010",
volume = "115",
number = "A12312",
pages = "10",
month = "Dec.",
keywords = "hemispheric asymmetries, geomagnetic storm, ionospheric F
region.",
abstract = "The main purpose of this investigation is to study the ionospheric
F region response induced by the intense geomagnetic storm that
occurred on 78 September 2002. The geomagnetic index Dst reached a
minimum of \−181 nT at 0100 UT on 8 September. In this
study, we used observations from a chain of 12 GPS stations and
another chain of 6 digital ionosonde stations. It should be
mentioned that, soon after the sudden commencement (SC) at 1637 UT
on 7 September, the TEC variations at midlatitude stations in both
hemispheres showed an F region positive storm phase. However,
during the recovery phase, a strong hemispheric asymmetry was
observed in the ionospheric response. While a TID type soliton was
observed to propagate in the Southern American sector, no TID
activity was seen in the Northern American sector. Also, in the
Southern Hemisphere, the TEC variations were less affected by the
geomagnetic storm. The Northern Hemisphere observations showed a
strong and long-lasting negative F region storm phase starting at
about 1000 UT on 8 September (lasting for about 24 h). A perusal
of TEC phase fluctuations and equatorial spread-F (ESF)
ionospheric sounding data indicates that, on the disturbed night
of 78 September, some stations showed the occurrence of ESF
starting at about 0000 UT (2000 LT) on 8 September, whereas other
stations showed that the ESF occurrence started much later, at
about 0800 UT (0500 LT). This hemispheric asymmetric response of
the ionospheric F region possibly indicates the presence of
different mechanisms for the generation of ESF along the various
latitudinal regions during the disturbed period.",
doi = "10.1029/2010JA015661",
url = "http://dx.doi.org/10.1029/2010JA015661",
issn = "0926-9851",
label = "self-archiving-INPE-MCTIC-GOV-BR",
language = "en",
targetfile = "jgra20750.pdf",
urlaccessdate = "15 jun. 2024"
}